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World Environmental and Water Resources Congress 2009: Great Rivers Proceedings of World Environmental and Water Resources Congress 2009

May 17–21, 2009 Kansas City, Missouri

Editor(s): Steve Starrett Ph.D., P.E., D.WRE

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ASSET MANAGEMENT

Select this Article		Bursts Identification in Water Distribution Systems I. Borovik, B. Ulanicki, and P. Skworcow ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)1 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The leakage reduction problem as a whole is complex and requires co‐ordinated actions in different areas of water network management, such as: direct detection and repair of existing bursts, general pipe rehabilitation programmes and operational pressure control. Water companies undertake a mixture of these complimentary actions. General pipe rehabilitation is the most costly and long term action, but is undertaken to improve a number of different factors including leakage and water quality. Operational pressure control is a cost‐effective action for reducing leakage over whole sub‐networks, and for reducing the risk of further leaks by smoothing pressure variations and is the subject of ongoing research. Detection and repair actions are targeted at sub‐networks where bursts are present. Benefits of quick burst repair include reduced water losses, reduced disruption to traffic, reduced consequent losses (e.g. from flooding), and also reduced disruption to customers' supplies, which is an important water industry performance measure. The existing methods typically use passive identification approach whilst the presented approach is based on the active identification procedure.

Select this Article		Damage Detection of Operating Transmission Mains with Measured Boundary Conditions Aaron C. Zecchin, Martin F. Lambert, and Angus R. Simpson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)2 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Transmission mains are a pivotal component in water distribution systems. As such, regular testing of these mains, for the purpose of identifying regions of damage and deterioration, is an important aspect of responsible infrastructure management. Much research has been done on the use of hydraulic transient methods to aid in the assessment of pipelines. These methods typically require the isolation of the pipeline from the system to create the ideal conditions under which testing can be performed. In many cases, it is not practical to isolate the transmission mains and take them off line for testing. However, testing in an operating environment can serve to confuse existing transient assessment methods, as these methods require known boundary conditions, such as valves or reservoirs. This paper proposes a method that does not require knowledge of a pipelines boundary conditions, but uses a special arrangement of pressure sensors to facilitate the assessment of desired sections of the pipeline. The approach is based on the use of a frequency‐domain model to analyze the pressure measurements and identify regions of damage and deterioration within the pipeline.

Select this Article		Evaluating Risk of Multi‐Segment Pipes for Prioritizing Pipe Rehabilitation M. Poulton, I. Kropp, and A. Vanrenterghem‐Raven ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)3 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The evaluation of risk at the individual pipe level can play an important role in the rehabilitation planning of water distribution systems. Yet pipe segments are generally arbitrarily defined in GIS or other databases and individual sections rarely make suitable rehabilitation entities on their own. In reality, groups of pipes need to be considered together for viable projects. The ability to group neighboring segments either prior to or subsequent to risk analysis has the potential to facilitate analysis and/or the actual practical rehabilitation. This paper looks briefly at the assessment of risk at pipe level before discussing how individual segments of pipe can be grouped into meaningful entities before or after such analysis. The objective is to maximize the benefit, in terms of risk avoidance, whilst minimizing the number of multi‐segment pipes proposed for rehabilitation. Data from case studies are used to illustrate any advantages or shortcomings of the methods proposed.

Select this Article		Water Distribution Systems Corrective Maintenance Supported by Real‐Time Use of Hydraulic Models Juan G. Saldarriaga, Susana Ochoa, César A. Niño, and Oscar J. Cortés ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)4 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This article presents a new tool that supports real‐time corrective maintenance of water distribution systems (WDS). This tool integrates Geographic Information Systems (GIS) with hydraulic modeling of WDS, providing a graphic interface in which, in the case of a failure, the operator can select the damaged pipe (usually a burst pipe), obtaining the following information from the support tool: (1) the exact valves that need to be closed to isolate and repair the burst pipe; (2) the amount and cost of water that is lost while the damage is not fixed; (3) the users that are left without service when closing the valves identified in (1); (4) the amount and cost of water required by users but not supplied to them because of the damage. In the developed tool, the identification of the valves that must be closed to isolate the burst pipe is carried out by means of a Recursive Iterative Algorithm (RIA). On the other hand, for the loading and display of information in the GIS, binary search and a fast ordering technique, known as Quick Sort, are used. The developed tool was applied to the WDS of Sector Estadio (250,000 inhabitants), which is a complex area of the city of Bucaramanga (Colombia); it proved to be a valuable operational tool which could also be useful for prioritizing damage repair.

Select this Article		Water Price Forecasting Method Based on Marginal‐Cost Theory: A Case Study in China L. I. Cui‐mei and L. I. U. Sui‐qing ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)5 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this paper is to evaluate the pricing of China water utilities according to past twenty year's data. An econometric model describing both water supply and demand is specified and estimated on utilities located in the east area of China. Based on the estimated technology and demand parameters, a new method of forecasting water price is presented. It used the marginal‐cost theory that is close to the historical data to establish the water price forecasting function, and according to the process of marginal‐cost function to build the forecasting model. We derive the estimated parameters and discuss estimates of returns to scale and elasticity of water demand, analyzing the current pricing of water utilities by comparing marginal costs and marginal prices. In a case study of Shanghai, these estimates are then used to simulate first‐best optimal pricing by solving a supply‐demand system in prices and quantities. Finally, we find that the marginal cost price is the optimal pricing scheme, which is much better than fixed charge price and average cost price.

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FIELD WORK

Select this Article		Assessing the Impact of Climate Change on Drinking Water Treatment Plant Design and Operation Zhiwei Li, Robert M. Clark, Steven G. Buchberger, and Y. Jeffrey Yang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)6 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper applied a water treatment plant (WTP) simulation model developed by the USEPA to evaluate effects of climate change on a WTP design and operation. The simulation model was validated using the Greater Cincinnati Water Works' Richard Miller WTP based on data collected for the Information Collection Rule (ICR) database. As part of the validation process, individual influent water quality parameters were “perturbed” and processed through the simulated Miller WTP to identify key influent water quality factors that significantly affect regulated contaminants in the treated water. TOC and ammonia were identified as key water quality parameters. After the validation process was completed, the simulation model for the Miller WTP was used to examine the impact on regulated contaminants of a set of influent water quality scenarios that might result from climate change. Results of the case study scenarios indicated that the existing Miller WTP operation might not be able to meet Safe Drinking Water Act MCL requirements. Therefore design and operational changes may be required to meet these climate change induced changes in source water quality.

Select this Article		Axial Dispersion Coefficients for Laminar Flows in Water Distribution Systems P. Romero‐Gomez, Z. Li, C. Y. Choi, and S. G. Buchberger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)7 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A dispersive transport component has recently been incorporated into the constituent transport equation used for modeling water quality in pressurized distribution systems. Among the various issues that arose from this major development, dispersion coefficients (E) relevant to water distribution systems still remain unknown. In order to quantify E values, researchers have considered the long‐established Taylor's theory (E^∗) and time‐dependent functions. However, discrepancies between theoretical and experimental approaches still exist because the former does not consider the transient nature of dispersion whereas the latter derives from the analytical relations that overestimate dispersion rates. The present study quantifies dispersion coefficients in pressurized pipes under laminar conditions by using Computational Fluid Dynamics (CFD). Assumptions made with CFD are few and mostly related to the velocity field in pipe flows. Consequently, the mass transports are obtained by solving the species equation over an axi‐symmetric domain. Next, the resulting spatial‐temporal constituent concentrations are used to estimate dispersion coefficient values determined by the method of moments (MOM) at equally‐spaced locations along the length of the pipe. With the aim of building a quasi‐analytical relation of E/E^∗ = β f_E = f(Re,T,Sc), transient simulations at a series of Reynolds numbers for laminar flows (Re < 2,100) were carried out in consideration of constituents with different molecular diffusivity in water. Among the various challenges that this study confronts, two are thoroughly described here: (i) the pre‐analysis needed to obtain a solution that is independent of the numerical setup and (ii) the CFD benchmarking solution required under conditions when Taylor's theory applies (T > 0.30).

Select this Article		Case Study: Homeowner's Preference Trade‐Offs Towards Plumbing Systems in Pipe Failure Prone Area Juneseok Lee, Darrell Bosch, Ewa Kleczyk, Eftila Tanellari, Andrea M. Dietrich, and Vinod K. Lohani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)8 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Pinhole leaks in copper plumbing pipes have become a nationwide concern because these leaks cause property damage, lower property values, and result in possibility of adversely affecting homeowners' insurance coverage. Multiple attributes of a plumbing system including cost, taste and odor impacts, potential for corrosion, health effects, warranty, convenience of installation, and proven performance in the market are considered when choosing an alternative plumbing material. Two phase surveys are conducted with selected homeowners in pinhole leak prone area in southeastern US community to observe their revealed and stated preferences. Health effects, taste and odor of water turned out to be the most important factors from the survey. In real life, however, homeowners were not well aware of these safety issues related with plumbing materials. It is recommended that water professionals should work on bridging the gap between public perception and research results.

Select this Article		Field‐Scale Assessment of a Multispecies Water Quality System: A Chloramination Study Matthew T. Alexander, Dominic L. Boccelli, and Margaret J. Kupferle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)9 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water distribution system network models are used to simulate both hydraulic and water quality characteristics in water distribution systems. These models primarily focus on modeling hydraulics and are unable to model more than one water quality parameter. EPANET‐MSX (Multi‐Species eXtension), a recently developed multi‐species water quality version of EPANET, has the ability to model complex multi‐species systems of water quality species. This study proposes to provide the first comprehensive evaluation of integrated models associated with chloramine dynamics, by‐product formation, and nitrification through the use of field‐scale measurements and distribution system network modeling. Hydraulic and multi‐species water quality simulations will be performed using EPANET‐MSX. This investigation will gauge the accuracy of EPANET‐MSX through comparison with a comprehensive set of field‐data. Successful implementation of such a model could change the way water distribution maintenance and operation is approached in the future.

Select this Article		Pressure vs. Flow Relationship for Pipe Leaks Thomas Walski, Brian Whitman, Mary Baron, and Fred Gerloff ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)10 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Leakage can be reduced by reducing pressure in a water distribution system. The magnitude of that reduction depends on the equation used to predict leakage. A common equation is to use a power function where the flow is estimated from the pressure terms raised to an exponent. There are a wide range of values reported in the literature for that exponent. Laboratory experiments were performed in which flow and pressure were measured for a wide range of leak shapes and sizes. The median value of the exponent was 0.54 which is lower than most reported but close to the theoretical value for an orifice. The high values in the literature can be explained in some cases as due to the method for estimating leak reduction. This is illustrated using a model of a small zone.

Select this Article		Seoul(Korea) Online Water Quality Monitoring of Drinking Water P. S. Shin, Y. R. Song, Y. J. Choi, and Y. S. Park ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)11 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the Metropolis of Seoul, Republic of Korea, more than 10.42million citizens are supplied with potable water by the waterworks Seoul metropolitan government. Seoul's waterworks now has a total of 6 treatment plants with a total daily production capacity of 5.10million m³ (2007). An average daily production of 3.34million m³ (2006) is guaranteed. This water is transmitted via a supply network consisting of more than 14,106Km of mains covering nearly 1.96 mil. taps. The distribution system includes 109 reservoirs (total storage volume: 2.35 million m³) that provide emergency storage, balance water demands, and equalize pressure. The Seoul Metropolitan Government has various policies aimed at providing our citizens with safe and tasty tap water. We have a real time monitoring system to thoroughly manage the production and supply processes from the water supply sources to every household. The automatic water quality monitoring system was completed in July, 2006 according to a Seoul Water‐Now Plan (Feb. 2001). The water quality is monitored for 24 hours from the water source supply to the tap to secure safety of water, and the data is positively used to raw water monitoring, optimum water purification treatment and safe water distribution control. The real‐time monitoring data is opened to the public through the homepage from 2008 March 21. Web site' address is http://water.seoul.go.kr/waternow/RealDataFullScale.php. 13 items are monitored including turbidity, residual chlorine, water temperature, etc. and 72 places consisting of 6 intakes, 6 water purifying plants and 60 supply places are monitored. It is planned to enlarge to 145 places to be monitored until 2010. As a result of running the system, The online monitoring system were contributed to maintain the safety of water quality from the source water to the tap water

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HYDRAULIC TRANSIENTS AND BIOFILMS

Select this Article		Air/Vacuum Valve Breakage Caused by Pressure Surges — Analysis and Solution Guohua Li, Ph.D., Christopher C. Baggett, P.E., and Roberto A. Rosario, E.I. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)12 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract An improperly designed air/vacuum valve could generate excessive pressure surges in the valve caused by the instant valve closure and the rapid expulsion of air. This study characterized dynamics of the air valve and other air valves. Simulation results in a case study showed that large pressure spikes could be generated in the air valve. An air accumulator could reduce the surge pressures. Theoretical analysis demonstrated the feasibility of an air‐throttling orifice and the mechanism of an anti‐slam device in reducing pressure spike values. The study also illustrated that the excessive pressure surges generated in the valve tend to be damped out in the pipe main and the valve connections tend to experience higher pressure surges for potential breakages.

Select this Article		The Impact of Biofilm Development on Pipe Roughness and Velocity Profile Martin Francis Lambert, Ryan Wilson John Edwards, Sean James Howie, Benjamin Bernard De Gilio, and Shane Pearse Quinn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)13 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The unpredictable impact of biofilms on friction in pipes causes difficulty in accurately designing for pipe roughness in biofouled pipes. The effects of biofilm growth on pipe roughness were experimentally investigated with the variation of growth conditions of velocity, diameter and water source. The results showed that differences in the growth velocity and source water altered the equivalent sand grain roughness of the biofouled pipes. The variation of the friction factor with Reynolds number in these biofouled pipes was not as expected for a rough surface and did not follow the traditional pipe friction equations. In addition, the change to the pipe velocity profile once biofilm had developed was analysed. One of the most important findings was that the Von Karman constant was significantly lower than normal in the biofouled pipes and that it varied with velocity. This enabled a modified version of the Colebrook‐White equation to be created to describe the friction factor variation with Reynolds number in biofouled pipes. This research provides a basis for a method to predict the impact of biofilm development on pipe roughness.

Select this Article		In‐Line Partially Closed Valves: How to Detect by Transient Tests S. Meniconi, B. Brunone, and M. Ferrante ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)14 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Reliable and quick techniques are needed to locate and estimate the asset of in‐line partially closed valves in pressurised pipes. The methodology considered in this paper is based on the analysis of transient tests. As a matter of fact, singularities (e.g., junctions, partial blockages, partially closed in‐line valves, leaks) give rise to reflected waves whose arrival time and amplitude — recorded in one or more sections of the pipe — allow their detection. Transients are generated by means of a total and fast closure of an end valve and the pressure time‐history — referred to as pressure signal — is measured at a section immediately upstream the end valve. In the paper, first some numerical simulated signals show that this kind of analysis can be useful for locating the valve and determining its asset, also by means of two simplified numerical models. Then some results of an extensive laboratory campaign carried out at the Water Engineering Laboratory (WEL) of the University of Perugia, Italy, are reported.

Select this Article		Simple Model of Attachment and Detachment of Pathogens in Water Distribution System Biofilms I. Schrottenbaum, J. Uber, N. Ashbolt, R. Murray, R. Janke, J. Szabo, and D. Boccelli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)15 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The influence of wall biofilms on the transport of pathogens through a water pipe is mathematically described using an attachment — detachment model. The process coefficients of attachment and detachment are estimated from experimental data. A biofilm annular reactor model is presented and model predictions are compared to experimentally derived bulk phase and biofilm‐sorbed pathogen data. The resulting pair of parameters, through minimizing the weighted root mean square error, are used in a single pipe model, and the results are discussed.

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NETWORK MODELING 1

Select this Article		Impact of Storage Tanks on Energy Consumption in Municipal Water Distribution Systems Santosh R. Ghimire, S. M. ASCE and Brian D. Barkdoll, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)16 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Municipal water distribution systems (MWDS) use a significant amount of electrical energy for the pumping of water from low elevations to higher ones. The use of electrical energy has an effect on pollution emissions and, therefore, potential global climate change as well. There are many aspects of MWDSs that affect energy usage. The properties of the storage tank(s), namely diameter and tank maximum water level, are singled out here for analysis. Various values of these tank parameters are modeled on seven MWDSs of various sizes using a system solver and the energy usage recorded. It was found that when averaged over all seven systems analyzed (1) a reduction of tank diameter of 20% results in approximately a 4% energy savings, and (2) the reduction of maximum tank water level by 20% results in approximately a 1% energy reduction.

Select this Article		Hydraulic Analysis of Water Distribution Network Using Harmony Search Zong Woo Geem ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)17 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract So far, water distribution networks have been hydraulically analyzed by using various techniques such as Hardy Cross method, Newton‐Raphson method, linear theory, and Todini algorithm. This study proposes a novel technique for the analysis of water distribution networks using a phenomenon‐mimicking optimization algorithm, harmony search (HS). The HS algorithm mimics the behaviors of musicians in improvisation process, where they play musical notes based upon randomness, experience, or variation of experience. In order to use the HS optimization algorithm, the network analysis is formulated as an optimization problem where energy conservation equation is incorporated in an objective function and mass conservation equations are incorporated in constraints. The proposed HS model is successfully applied to two example networks.

Select this Article		Integrated Hydraulic Analysis and Data Management Tool for Water Supply Systems in Developing Countries Philipp Klingel and Nicolai Guth ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)18 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In developing countries hydraulic models of water distribution systems are rarely used efficiently. The lack of appropriate know‐how is one reason. Further, water distribution networks are dynamic technical systems changing rapidly due to maintenance works and network extensions. Therefore, the foundation for all technical tasks to assure a sustainable water supply is the deep going knowledge of the system. In developing countries the available system data is usually not up to date and of poor quality due to missing appropriate data management concepts. Integrating the data management and the hydraulic model as well as adapting the resulting tool to local constraints remedies the challenges resulting from the situation described above. Furthermore, linking the necessary work‐flow of data collection to the tool eases the model implementation as well as the subsequent database update. In this paper a novel integrated data management and hydraulic analysis tool for water supply networks and linked work‐flows specifically tailored towards its application in developing countries is presented. Based on a project of the German‐Algerian technical cooperation in Béni Abbès the application of the tool is demonstrated.

Select this Article		The Impacts of Demand Variability on Distribution System Hydraulics and Transport Xueyao Yang and Dominic L. Boccelli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)19 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A stochastic water demand generator (PRPsym) and a well known distribution system network solver (EPANET) were linked together to analyze the impact of water demand variability on the underlying hydraulics and transport in a distribution system. The modified EPANET example 2 network model was used as a template and test network model for both hydraulic and water quality simulations at three different temporal aggregations (1‐hour, 10‐minute, and 1‐minute). The mean, standard deviation and coefficient of variation at each hour for both hydraulic and water quality parameters were calculated for all nodes or links. Results showed that decreasing temporal aggregation of the water demands leads to increased flow rate variability. The increase in flow rate variability is related to the increased demand variability and the localized flow reversals that alter the travel path. The increase in flow rate variability was more evident in the links located at edges of the system rather than the main trunk lines. In addition to the hydraulics, water age simulations — used as a water quality surrogate — indicate that increased demand variability can significantly impact water quality simulations by altering residence times and travel paths. These preliminary results suggest that there are likely portions of a distribution system where typical modeling assumptions do not adequately represent localized water quality conditions.

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NETWORK MODELING 2

Select this Article		Augmented Gradient Method for Head Dependent Modelling of Water Distribution Networks Calvin Siew and Tiku T. Tanyimboh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)20 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When analysing a pressure deficient network, it is crucial that the pressure dependent nature of nodal outflows be taken into account. The head dependent analysis (HDA) produces an accurate representation of the nodal outflows and network hydraulic performance. This is essential when modelling pipe leakages, network redundancy and reliability. These are vital aspects often considered in the optimization of a water distribution system (WDS). This paper describes an approach for head dependent analysis in which an embedded function for the head‐outflow relationship is incorporated in the Gradient Method (GM). The procedure is capable of simulating both normal and deficient network operating conditions effectively. Results based on networks from the literature show that the proposed method is robust and converges smoothly and rapidly.

Select this Article		Enhanced Global Gradient Algorithm: A General Formulation L. Berardi, O. Giustolisi, and E. Todini ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)21 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The behaviour of a looped water distribution network, operating under pressure in steady flow conditions, can be modelled by imposing mass and momentum conservation. When distributed demands along the pipes are present, they tend to be represented as lumped withdrawals at the pipes ending nodes. Although such simplification preserves mass balance, it might cause significant head loss errors which may lead to inconsistent results. Giustolisi and Todini (2008) recently proposed a correction scheme within a modified Global Gradient Algorithm (GGA) under the common assumptions of Darcy‐Weisbach head loss formula and pipe friction factors independent from the flow regime. This paper provides an extension of the mentioned approach to any generic monomial head loss formula, so it can be easily incorporated into existing commercial water distribution network simulators.

Select this Article		Enhanced WDN Analysis: Representation of Actual Pipe Connections O. Giustolisi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)22 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The classical assumption of representing the total demand along a pipe as two lumped withdrawals at its terminal nodes is hitherto common. It is a simplification of the network topology which is useful in order to drastically reduce the number of nodes during network simulation. Conversely, this simplification does not preserve pipes' energy balance equation and, for this reason, it is a wrong approximation that could generate large head loss errors. This paper presents an extension of the Global Gradient Algorithm (GGA) which entails a modified GGA permitting the effective introduction of the lumped nodal demands, and without forfeiting a correct pipe head loss, by means of a pipe hydraulic resistance correction.

Select this Article		Identification of the Hydraulic Model from Operational Measurements for Supervisory Pressure Control Ping Li, Ian Postlethwaite, Emmanuel Prempain, Bogumil Ulanicki, and Ridwan Patel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)23 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The operational pressure control is a cost‐effective way to leakage reduction and many pressure control methods and algorithms have been developed. Whilst the pressure control algorithm is model‐based, the hydraulic model of the considered distribution network is not always available. Therefore, this paper will focus on the development of an aggregated hydraulic model of the network considered, in particular, identification of a leakage enhanced model using the operational measurements or the available historical data. This will enable a pressure optimisation algorithm to calculate the optimal pressure schedules for the implementation of a pressure control scheme. The identification problem is formulated as a parameter estimation problem in this paper and a least‐square based method is derived for estimating the parameters in the model. A case study provided by a UK water company is performed to illustrate the use of the method and the identification results from real operational data are presented.

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NETWORK MODELING 3

Select this Article		An Operative Approach to Water Distribution System Rehabilitation L. Berardi, O. Giustolisi, and D. Savic ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)24 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The selection of the most effective course of action for pipe rehabilitation is crucial to avoid the uncontrolled deterioration of water distribution systems (WDS). Moreover, it provides a rare opportunity to modify some elements of the existing infrastructure in order to meet the present service requirements. For instance, a rehabilitation plan could be aimed at simultaneously improving system reliability, pressure levels and/or leakage reduction. In this work WDS rehabilitation is formulated as a multi‐objective optimization problem where decision variables for each pipe are “do‐nothing” or “replace” by selecting from a set of commercial pipe diameters. It is shown that the solutions returned by a multi‐objective genetic algorithm (MOGA) in such a complex decision scenario although good, could not be easily used to support decision making. A prioritization strategy is developed and presented which is based on MOGA solutions and provides an effective tool for both analysts and decision makers.

Select this Article		Calibration of Water Distribution Network Models as a Tool for Detecting Missing and Erroneous Cadastral and Hydraulic Information Juan G. Saldarriaga, Susana Ochoa, Daniel Rodríguez, and César M. Jurado ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)25 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the first place, this paper presents an examination of the effects of missing cadastral information on the modeling and calibration of water distribution networks (WDN). For this purpose, cadastral errors were artificially introduced to the hydraulic models of the WDN of three cities of the province of Valle del Cauca (Colombia), with population in the range of 15,000–30,000 inhabitants. The cadastral errors were introduced by eliminating some pipes from the unaltered models using the resilience index as selection criterion. From this examination, typical responses observed during the calibration process were associated to specific topological and hydraulic errors and it was also noted that there is a direct relation between the resilience index and the effect of the removal of a certain pipe on the hydraulic performance of the model. In the second place, after identifying the effects of missing and erroneous cadastral and hydraulic information on the calibration of WDN models, the inverse procedure was carried out: the calibration process was used as a tool for detecting missing and erroneous cadastral and hydraulic information. This methodology was successfully applied to the WDN of Sector Estadio (250,000 inhabitants), which is a complex area of the city of Bucaramanga (Colombia); through the calibration of this WDN, errors such as failing water meters, pipes and valves that existed in the real system but were not in the model, significant errors in pipe diameters in the model, among others, were identified.

Select this Article		Integrated Planning for Dual Distribution Systems Nabin Khanal, Vanessa Speight, Venkatraman Radhakrishnan, Tim Francis, Laurel Passantino, and James Swanson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)26 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The southwest region of the US is facing problems with limited water resources and population growth. Some water utilities in the region are taking a proactive approach to planning that incorporates acquiring water resources in the future. Reusing treated wastewater effluent (reclaimed water) is one of the most viable solutions to expand water resources under conditions of fresh water scarcity. Reclaimed water can be used primarily to fulfill the outdoor demands such as landscape irrigation and other non‐potable water use. The possibility of treating the reclaimed water to the standards of potable water and using the same distribution system to supply the water is generally not considered to be a viable option. However, cities are studying options to provide dual distribution systems, with separate potable water and reclaimed water systems. Traditional water master plans analyze potable water distribution systems, however with the limitations in water resources, new master plans have started to include consideration of reclaimed water infrastructure. This integrated approach to master planning will help utilities to understand the dynamics of their water sources and utilize the resources effectively. Medium‐sized utilities such as the City of Surprise in Arizona have taken the initiative to implement such integrated water master planning to evaluate the feasibility of dual distribution systems.

Select this Article		Reliability Analysis of Water Distribution Systems Using Graph Decomposition Jochen Deuerlein, Andreas Wolters, Dietmar Roetsch, and Angus R. Simpson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)27 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water supply utilities are increasingly being confronted with growing maintenance requirements in order to provide a reliable and cost efficient operation of the water distribution system in order to deliver high standard drinking water. One specific challenge is to find a satisfactory compromise between the contradictory objectives of saving investment cost and meeting the increasing expectations of customers. A valuable tool for the planner is reliability analysis of the system that for instance provides information about the importance of each particular pipe in determining the total reliability of the system. This information can be used to decide which pipes should be replaced next or potentially duplicated to reduce the risk of system isolation. Since structural (topological) reliability only considers the connectivity of the network a new approach for the calculation of structural hydraulic reliability is presented in this paper. The algorithmic implementation is based on a decomposition method of the network graph that greatly enhances both the calculation of pure structural reliability as well as structural hydraulic reliability.

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NETWORK MODELING 4

Select this Article		A Framework for Alternative Formulations of the Pipe Network Equations Angus R. Simpson and Sylvan Elhay ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)28 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The aim of this paper is to revisit the formulations of the equations for flows and heads in water distribution systems and provide clarity for a logical presentation of a framework for the different formulations. Five formulations are described including 1) flow equations where the equations are formulated only in terms of the unknown flows in a network 2) head equations 3) loop flow equations 4) flow and head equations and 5) the Todini and Pilati flow and head formulation. Graph theory is used to show how many unknowns are required to be solved for in each of the five formulations. A Newton solution method is derived for the flow formulation and the Todini and Pilati formulation.

Select this Article		Inexpensive Modeling of Intermittent Service Water Distribution Networks J. A. Cabrera‐Bejar and V. G. Tzatchkov ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)29 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Intermittent supply is prevalent among developing countries. Inequitable water distribution, possible water contamination, wasting water, coping costs of consumers and water providers, meter malfunctioning and inconvenience to consumers are some of its consequences. There are two major views on how this problem should be considered. The first view looks at a transfer to the 24‐hour supply by reducing water loss and adding new supply sources, while the other accepts intermittent supply as a reality and looks for appropriate design and operation methods that can minimize its negative impacts. Important differences between intermittent and continuous service water distribution networks operation should be considered in the second case, such as initial network charging, pressure‐dependent water demand, and design pressure. In this paper, the use of known free public domain network models, such as SWMM for modeling initial pipe network charging and EPANET for modeling the network intermittent operation, is proposed and exemplified.

Select this Article		Operational Perspective of the Impact of Failures in Water Distribution Systems J. Bicik, Z. Kapelan, and D. A. Savić ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)30 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Failures in water distribution systems (WDS) occur on daily basis, requiring the fast esponse from WDS operators. This paper presents an impact model which investigates he adverse effects of failures from an operational rather than strategic perspective in rder to provide a better insight into their development over a given impact horizon. The erformance indicators (PI) currently in place have been found inadequate and a set of ew operational PI considering the magnitude, duration and sensitivity of customers has een introduced. The proposed operational impact model has been applied on a case tudy where a pressure‐driven hydraulic model has been coupled with a geographic nformation system (GIS) and a discolouration model in order to provide a omprehensive overview of the failure to allow WDS operators to make more informed ecisions.

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NETWORK MONITORING AND SAMPLING

Select this Article		New Concepts for Meter Placement in Water Distribution Systems for Demand Estimation Doo Sun Kang and Kevin Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)31 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Kang and Lansey (2008a) have shown that water distribution system (WDS) nodal demands can be estimated in real‐time using pipe velocity measurements from a supervisory control and data acquisition (SCADA) system. The field measurements are key elements for the real‐time state estimation. However, the limited number of metering locations has been a significant obstacle for the real‐time studies and identifying locations to best gain information is critical. Previous studies for the data sampling mainly focused on minimizing either parameter or prediction uncertainties. However, reducing uncertainty does not guarantee a good fit for the model predictions in terms of the mean estimate. Therefore, robust objective criteria, that guarantee precise and accurate state estimates, must be applied. Here, an optimal meter placement (OMP) problem is formulated as a multi‐objective optimization model. Three distinctive objectives are posed: (1) minimization of nodal demand estimation uncertainty; (2) minimization of nodal pressure prediction uncertainty; and (3) minimization of absolute error between demand estimates and their expected values. Objectives (1) and (2) represent model precision while objective (3) describes model accuracy. The OMP problem is solved using a multi‐objective genetic algorithm (MOGA) based on Pareto‐optimal solutions. The trade‐off between model precision and accuracy is clearly observed from a simple network study and it is strongly recommended to use both criteria as objectives.

Select this Article		Online Hydraulic State Prediction for Water Distribution Systems Ami Preis, Andrew Whittle, and Avi Ostfeld ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)32 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes and demonstrates a method for on‐line hydraulic state prediction in urban water networks. The proposed method uses a Predictor‐Corrector (PC) approach in which a statistical data‐driven algorithm is applied to estimate future water demands, while near real‐time field measurements are used to correct (i.e., calibrate) these predicted values on‐line. The calibration problem is solved using a modified Least Squares (LS) fit method. The objective function is the minimization of the least‐squares of the differences between predicted and measured hydraulic parameters (i.e., pressure and flow rates at several system locations), with the decision variables being the consumers' water demands. The a‐priori estimation (i.e., prediction) of the values of the decision variables, which improves through experience, facilitates a better convergence of the calibration model and provides adequate information on the system's hydraulic state for real time optimization. The proposed methodology is demonstrated on a prototypical municipal water distribution system.

Select this Article		Sampling of Residential Water Use for Leak Control VIA Water Budgets C. Arena, A. Criminisi, A. Fortunato, and M. R. Mazzola ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)33 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The paper provides insights into the sampling techniques that may be employed to assess domestic water use for developing water budgets at district scale aimed at losses evaluation. The basic idea is to use only few meters to provide inference on the total use of a district metered area by standard statistical sampling procedures. Random and stratified sampling are compared with reference to the sampling fraction necessary to obtain estimates of the daily use totals (or means) with given precision and confidence level. An application with real data from a small, homogeneous group of connections in Palermo (Italy) shows how stratified sampling allows a considerable reduction of the sampling fraction. A sensitivity analysis on model parameters (group variance, precision, confidence levels) shows how stratified sampling is always a better option than random sampling and that results are mainly driven by precision, with a considerable increase of the required sample size when the desired precision shifts from 5% to 1%.

Select this Article		Smart Pipe — Nanosensors for Monitoring Water Quantity and Quality in Public Water Systems Yu‐Feng Lin, Chang Liu, and Jordan Whisler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)34 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A 2005 study by the American Society of Civil Engineers showed that six billion gallons of clean, treated drinking water disappears every day, mostly due to old, leaky pipes and mains. The amount is enough to serve the population of California. The approximate dollar cost, given varied water rates in different U.S. regions, is $12.5 million – $92 million. Moreover, leaking systems have wasted not only dollars but also priceless natural and energy resources for future generations. A current research project funded by the US Environmental Protection Agency — Midwest Technology Assistance Center is designed to improve water supply infrastructure via a highly‐advanced, cost‐efficient monitoring system. A research group led by the Illinois State Water Survey, in collaboration with the Department of Mechanical Engineering at Northwestern University, has been developing a “Smart Pipe” prototype: a multi‐sensor array to monitor water flow and quality using state‐of‐the‐art nanotechnology. Each sensor unit in the array will include sensors for pressure, flow velocity and temperature on a 2.5mm by 2.5 mm silicon skin. The Smart Pipe will be equipped with a wireless processor and antenna to transfer monitoring data via commercial wireless communication systems.

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NETWORK OPTIMIZATION 1

Select this Article		An Approach for Integrated Optimization of Wastewater, Recycled and Potable Water Networks Graeme Dandy, Alana Duncker, Joel Wilson, and Xavier Pedeux ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)35 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper outlines an approach to the integrated optimization of wastewater, recycled and potable water systems in an urban area. The approach will be demonstrated through consideration of a case study of the Hume corridor in Melbourne, Australia. A total of 44,000 new residential lots are planned in this area. These houses will have their garden and toilet connected to a Class A recycled water system. The recycled network will also incorporate some industrial demands. As the recycled water system will receive its inputs from wastewater treatment plants, the three networks had to be considered in an integrated fashion. The case study considered the development of two optimisation models, one for the wastewater system and the other for the potable and recycled water systems. The interface between the two models occurred at the wastewater and recycled water treatment plants. Values were set for the capacities of these plants for each model and they were adjusted to ensure compatibility between the two models. The recycled network was designed to the same level of service as the potable water network, e.g. 25 m minimum allowable pressure head at all demand nodes. As potable water top‐up of the recycled system is to be considered, it was found that the potable water network needed to carry flows greater than potable peak hour demands. The results obtained clearly indicated the value of using evolutionary algorithms in an integrated fashion to optimize potable and third pipe systems. Application of this approach to other areas is likely to make third pipe systems more attractive and to lead to significant savings in the use of limited water supplies.

Select this Article		Application of Optimization Technology to Water Distribution System Master Planning C. K. Rogers, M. Randall‐Smith, E. Keedwell, and R. Diduch ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)36 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the application of optimization techniques to the development of a phased expansion plan for the City of Ottawa's water distribution system. The approach involved an iterative process where capacity‐driven solutions generated by an optimization model were evaluated for reliability of supply during failure conditions and water quality characteristics in order to update constraints for subsequent re‐optimization. An infrastructure solution and phasing plan is presented. It was found that the approach is sound, but the number and variety of alternatives must be limited to achieve reliable results from the optimization model.

Select this Article		Industrial Distribution System Simulation for Optimal Water Resource Assignment Using Probabilistic Tabu Search S. H. H. Nourzad and M. H. Afshar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)37 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water of almost any quality has value so all operators need to learn how to use less, recycle more and to keep it as clean as possible. In many cases, the mineral industry, as a significant water user and wastewater producer, has the capacity to substitute poorer quality water for mining and mineral processing. Complex optimization problems and their challenges have been considered by the researchers around the world over several past years. Tabu search (TS) is a powerful searching algorithm based on principles of intelligent search. We propose in this work a probabilistic improvement to the selection procedure of TS. In this article, two methods are presented: Rank Based Probabilistic Tabu Search (RBPTS) and Fitness Based Probabilistic Tabu Search (FBPTS). Finally, we try to find optimal water resource assignment for an industrial copper complex distribution system. Anyhow, this is an applicable case study in industry.

Select this Article		Optimal Pump Scheduling by Linear Programming M. F. K. Pasha and K. Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)38 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Energy is one of the largest water utility expenses. This cost is greatly associated with the pump operation. An optimum pump schedule can reduce the cost significantly while maintaining hydraulics in an acceptable range. In this paper, the pump station relationships are linearized using relationships among energy required, pumping flow, demand factors and tank storage or tank water levels. A linear programming (LP) optimization problem is formulated and solved for a single tank system for the optimal pump schedule to minimize energy cost. This LP model can be solved very quickly for a “near optimal” solution. Available online data can be then incorporated to update the schedule each hour in real‐time. This paper describes preliminary methodologies that can be used to optimize the pump schedule and reservoir control. Future work will extend the approach to multiple tanks and pump station systems, better pump curve representations, and spatially variable demands.

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NETWORK OPTIMIZATION 2

Select this Article		An Integrated Approach for Distribution System Hydraulic Criticality and Emergency Response Laura Jacobsen, P.E., Manager, Planning Division, Sri Kamojjala, P.E., Senior Civil Engineer, and Brian Bowler, P.E., Senior Civil Engineer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)39 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Determining the hydraulic criticality of distribution system components is key to asset management and emergency response. Evaluation of the hydraulic criticality of large distribution system facilities involves compiling a significant amount of information such as spatial data, customer information and hydraulic model results. An integrated approach which leverages information compiled during the hydraulic demand distribution process for evaluating hydraulic criticality will be outlined. Benefits of the integrated approach for a) asset management, b) shutdown analysis and c) emergency response will be presented.

Select this Article		Decision Making under Information Constraints Jianhua Xu, Jeanne M. VanBriesen, M. ASCE, Mitchell J. Small, M. ASCE, and Paul S. Fischbeck ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)40 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The purposes of placing sensors in water distribution systems vary from complying with water quality regulations, monitoring accidental contamination events, and detecting intentional contamination events. The information available to water utilities varies: some only have information on the topological structure of their systems; some have calibrated hydraulics models for their systems; and some even have water quality models for their systems. Different sensor location models have been proposed for the different purposes, targeting the objectives of maximizing the coverage, minimizing the contaminant travel time prior to detection, minimizing the contaminated water consumed prior to detection, and/or minimizing the population at risk prior to detection. These different sensor location models require different computational efforts and the availability of information on water distribution systems to different extents. The current sensor location models proposed mainly include graph‐theory‐based model (network analysis), deterministic optimization models, stochastic optimization models and robust optimization models. In this paper, we develop a protocol to help water utilities to select sensor location models based on the specific purposes of sensor placement, the information available to the water utilities, and the computational requirements of the models.

Select this Article		Optimal Distribution of Pressure Measurement Points in Water Distribution Networks Hui Zhang and Tinglin Huang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)41 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The pressure similarity method is proposed to get the optimal distribution of pressure measurement points for water distribution networks. This kind of optimal distribution is mainly composed of two steps. Firstly, the pressure similarity coefficients of any two nodes should be calculated to obtain the similarity coefficient matrix. Then all the nodes can be grouped through clustering analysis on the matrix and the pressure measurement points can be chosen out. The application on a practical network shows that the pressure similarity method can reflect the regional characteristics of network pressure and the result is reasonable. This method is very useful for network further study such as state simulation, optimal scheduling and accident early‐warning.

Select this Article		Scalable Parallel Computing Framework for Pump Scheduling Optimization Zheng Yi Wu and Qi Zhu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)42 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract As multi‐core personal computers (PC) have become popular and widely available for various computation tasks, developing parallel computing methods are imperative for taking the full capacity of the multi‐core machines. This paper reports on the analysis and comparison of different paradigms for portable parallel computation on single multi‐core PC and a cluster of PCs. It summarizes the strength and weakness of various parallel and distributed computation models. A scalable and portable parallel optimization framework has been developed and applied to water distribution pump scheduling to improve energy efficiency. It is implemented as a generic optimization method for hydraulic engineers to optimize the pump operation policy in order to maximize energy cost efficiency. An example study is presented to demonstrate the application of the parallel and distributed optimization model. The results show a linear speedup has been achieved for the parallel optimization of pump scheduling.

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NETWORK SECURITY 1

Select this Article		A Multi‐Objective Evolutionary Computation Approach to Hazards Mitigation Design for Water Distribution Systems Lufthansa Kanta, Kelly Brumbelow, and Emily Zechman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)43 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract One of the critical public safety roles for water distribution systems (WDS) is suppression of urban fire events. Previous studies have investigated WDS rehabilitation for mitigation of potential fire events with a major focus on improving fire flows by pipe enlargement. However, pipe enlargement can cause water quality problems and place public health at risk during normal operational periods. Thus a novel approach is required to effectively address the conflicting goals of the WDS: reliable delivery of water during normal as well as emergency conditions, meeting water quality standards, and finding cost‐effective design and rehabilitation options. In this study an evolutionary computation‐based multi‐objective optimization‐simulation framework is developed to design effective mitigation strategies for urban fire events for water distribution systems with three objectives: (1) minimizing fire damages, (2) minimizing water quality deficiencies, and (3) minimizing the cost of mitigation. An elitist non‐dominated sorting genetic algorithm (NSGA‐II) is modified by incorporating an evolution strategy (ES) to address difficulties for heuristic algorithms posed by WDS problems. Implementation of this methodology generates Pareto‐optimal solution surfaces that express the trade‐off relationship between fire damage, water quality, and least cost objectives. Thus, the method provides decision makers with the flexibility to choose a mitigation plan for urban fire events best suited for their circumstances. Each Pareto‐optimal solution comprises a set of pipes to be enlarged to achieve increased fire flow and the corresponding diameters of these pipes. The algorithm is illustrated with several test functions. The Micropolis virtual city is then used to demonstrate the application of the proposed methodology to a complex WDS.

Select this Article		Multi‐Objective Sensor Placements with Improved Water Quality Models in a Network with Multiple Junctions R. G. Austin, C. Y. Choi, A. Preis, A. Ostfeld, and K. Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)44 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Concerns about the security of water distribution systems have lead to increased interest in sensor placement in water distribution systems. Due to the cost of both placing and maintaining these sensors, the number of sensors used must be limited. These constraints make the sensor deployment locations crucial in a water monitoring system. Many studies, based on differing algorithms and objective functions, have sought to determine ways to optimize sensor location. These studies have largely relied on current water quality models that assume perfect mixing at pipe junctions. However, it has been shown that using a water quality model that accounts for imperfect mixing (AZRED) at pipe intersections produces outcomes that differ from those produced by studies that assume perfect mixing and, consequently produces a different scheme for optimal sensor placement. The current work uses a multiobjective approach that relies on the non‐dominated, sorted algorithm II. The study seeks, first, to contrast the use of the AZRED water‐quality model to the use of water quality models that assume perfect mixing, and, second, to propose a more comprehensive approach to sensor placement. By using a simpler objective of optimizing for complete sensor coverage, the study will expand on pervious work that made this comparison. An example network is analyzed using both AZRED and EPANET, and the results are compared.

Select this Article		Robust Sensor Placement for Detecting Adversarial Contaminations in Water Distribution Systems Andreas Krause and Carlos Guestrin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)45 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Drinking water distribution systems (WDS) are complex and dynamic systems. The intentional introduction of a contaminant could theoretically be detected by a network of sensors placed at nodes in the system. Optimizing the placement of these hypothetical sensors for metropolitan area size WDS is an important research challenge. Recently, the Battle of the Water Sensor Networks led to the development of several promising techniques for deploying sensors in large, complex networks. However, this challenge focused on designing sensor networks that detect random, accidental contaminations well. In order to guard WDSs against malicious attacks, sensor network detection performance has to be optimized with respect to the worst possible contamination. We recently developed a new algorithm, Saturate, that can efficiently solve large robust sensor placement problems. The obtained solutions are provably close to optimal. Our algorithm can handle imprecise sensors that can fail. Our method can also be used to obtain placements that simultaneously perform well both for malicious (i.e., worst‐case) contaminations, as well as accidental (i.e., average‐case) contaminations. We report results from applying our method to a large hypothetical distribution system with more than 12,000 nodes.

Select this Article		Sensor Network Design and Performance in Water Systems Dominated by Multi‐Story Buildings Robert Janke, Terra Baranowski Haxton, Walter Grayman, Rakesh Bahadur, Regan Murray, William Samuels, and Tom Taxon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)46 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper reports on the modeling of CWS sensor network designs for two real water systems. The first system is small and simple and the model has been artificially modified to include multi‐story buildings. The second water system is actually dominated by multi‐story buildings but its base model does not contain any micro‐level detail. Geographical information system (GIS) tools and site‐specific information are used to construct and arrange reasonable representations of the high rise buildings into the model. For each water system, EPANET simulations are performed along with public health impacts assessments and sensor network design optimizations. Evaluations are made between the skeletonized models (base models without post‐service connection detail) and the multistory building‐enhanced models to assess the performance of sensor networks to reduce public health impacts.

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NETWORK SECURITY 2

Select this Article		Comparative Evaluation of Two Algorithms for Locating Contaminant Ingress Points Hailiang Shen, Edward McBean, and Mirnader Ghazali ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)47 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A procedure involving Data Mining based on Flow Direction and shortest flow time (DMFD) is described, which consists of two components: (i) possible ingress nodes (PINs) identification and (ii) probability quantification. PINs identification is completed based on the flow information, i.e. the flow direction and time in each pipe. Through shortest time which is calculated by Dijksta algorithm, from one node to a specific sensor, ingress time in the node is obtained. A distance metric is described to quantify the probability of one node as PIN. A multi‐stage response is described to decrease the elapsed time before a contaminant ingress event is identified and responded to, which is essential to minimize the risk from consumption of the hazard. The roles of two algorithms, namely a Data Mining method based on Injection and Detection information (DMID) and DMFD, are examined. A case study is employed in a network with 285 nodes and 5 sensors. The five sensors all alarm to the injection event. With DMID, the number of PINs is decreased from 44 in the 1^st stage to 18, 11, 11 and 11 subsequently; For DMFD, the number is reduced from 44 in the 1^st stage to 21, 21, 21 and 21 in the following stages; DMID identifies the true intrusion node 44 with the highest probability in the five stages, while DMFD identifies it with the highest probability in the 3^rd and 4^th stage; the run time of both DMFD and DMID is less than 2 min, which suggests the two are effective in guiding emergency response.

Select this Article		Comparison of Pressures Simulated using Transient Analysis with Field Data from a Full‐Scale Distribution System G. Ebacher, M.‐C. Besner, J. Lavoie, B. S. Jung, B. W. Karney, and M. Prévost ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)48 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Negative pressures were measured in a full‐scale distribution system following low pressure events at a water treatment plant. Transient analysis was used to model three downsurge events and compare the simulated pressure profiles with field measurement data. The objective of this work is to assess the source of uncertainty and variability associated with the estimation of intrusion volumes calculated by a transient analysis model. This assessment was conducted by comparing actual field pressure measurements and model outputs under various model settings (e.g., cavitation head, wave speed). For the three downsurge events, the modeled pressure profiles matched reasonably well with the measured pressures, as long as the pressures remained positive at a site. When the pressures reached negative values, the amplitude of the modeled pressures was larger than that of the recorded pressures. The difference between measured and modeled pressure is strongly related to a greater energy dissipation in the real distribution system, which is affected by the uncertain presence of air in pipes, the level of network skeletonization, and the allocation of demand. The estimation of intrusion volumes and risk for public health is directly affected by the pressure results obtained using transient analysis. Comparison to field data is therefore important to evaluate the accuracy of such a process.

Select this Article		Effects of Redesign of Water Systems for Security and Water Quality Factors Walter M. Grayman, Regan Murray, and Dragan A. Savic ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)49 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water distribution systems are typically designed based on hydraulic and cost considerations. In the United States, most urban water systems are looped systems with large pressure zones that serve customers in regions of different elevation. In the United Kingdom, water distribution systems are frequently further subdivided into zones of several thousand connections called district metering areas (DMAs) in order to track and control water leakage. In two case studies, starting with existing large looped water system designs, the current systems are redesigned to: (1) approximate a typical DMA design; and (2) provide additional control and isolation capability in order to improve the water security of the system. The systems are then compared in terms of four metrics: (1) fire flow; (2) water age; (3) water security; and (4) reliability. Though the results of the analysis may not necessarily be generalized beyond the case study examples, the methodology provides a mechanism for evaluating alternative water system designs, and provides insight into the effects of water security criteria on system design.

Select this Article		Propagation of Chlorine Demand Signals Induced by Microbial Contaminants in a Drinking Water Distribution System D. E. Helbling, P.E., Ph.D. and J. M. VanBriesen, Ph.D., A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)50 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Chlorine residual concentration is used as a protection from accidental and intentional intrusion of microbial contaminants in distribution systems. Monitoring chlorine residual with real‐time sensors may enable detection of such intrusions. However, this necessitates prediction of chlorine levels and how they change under normal conditions and in the event of a microbial intrusion event. Existing multispecie models require knowledge of specific reaction kinetics between chlorine and complex cellular matrices that are unlikely to be known a priori. Rather, we propose utilization of a parallel first order rate expression describing microbially‐induced chlorine decay over a wide range of conditions. The model can be parameterized using a limited number of batch experiments. The model formulation is then integrated into EPANET‐MSX using the programmer's toolkit. We present simulations of a series of microbial events in a small distribution system using the model. Our results indicate that change in residual induced by microbial intrusion events can be simulated in distribution system models. Chlorine residual signals can thus be predicted. Event detection is limited by lack of control of chlorine concentration at the time and location of the contaminant event, the unique species‐specific chlorine reaction kinetics, and the changing demand patterns in the system.

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NETWORK SECURITY 3

Select this Article		A Markov Chain Monte Carlo Implementation of Bayesian Contaminant Source Characterization in Water Distribution Systems under Stochastic Demands Kenneth W. Harrison and Hui Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)51 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bayesian analysis is applied to the problem of probabilistic source characterization in water distribution systems. An implementation of the Markov Chain Monte Carlo (MCMC) method is tailored to water distribution systems. The likelihood function, a key component of Bayes' rule, is approximated using a Monte Carlo‐based stochastic water demand model. Limitations of the approach are also discussed.

Select this Article		Conditioned Backward Probability Modeling to Identify Contamination Sources in a Water Distribution System R. M. Neupauer and M. K. Records ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)52 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract If a chemical or biological agent is released into a water distribution system, sensors that are installed in the pipe network may detect the contamination as it travels through the system. To minimize the adverse impact of the contaminant release, the source must be characterized to determine the extent of the contamination and to remediate the contaminated area. We develop an adjoint‐based backward modeling approach that uses the collected sensor data to identify the location and timing of the release. In the adjoint model, the sensor location is treated as a source of probability, and the probability is transported upgradient and backward in time to obtain probability density functions (PDFs) that describe the random time in the past that the observed contamination was at a particular upgradient position. These PDFs can be used to identify the source location and release time. Conditioning these PDFs on the measured concentrations improves their accuracy and decreases their uncertainty. We demonstrate the effectiveness of this method by using it to characterize a contaminant source in a hypothetical water distribution system.

Select this Article		Real‐Time Implementation of Contamination Source Identification Method for Water Distribution Systems Annamaria E. De Sanctis, Sam Hachett, James G. Uber, Dominic L. Boccelli, and Feng Shang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)53 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A contamination source identification methodology should be continuously run in real time to provide timely information about contamination event status. The method should be robust with respect to uncertainty and variability in factors affecting the network hydraulic model. This work assesses the impact of hydraulic modeling errors on the performance of a source identification algorithm. Preliminary results evaluate the effect of demand estimation errors on the performance of the identification algorithm. Results suggest the source identification method can be robust to the types of errors investigated. It is stressed, however, that broader conclusions can not be drawn, because the tests consider only one network test case, and the true statistical characteristics of stochastic demands are unknown. Furthermore, the particular example chosen assumes optimistic scenarios for demand estimation. The results provide a methodology and motivation for continuing to investigate the true performance characteristics of real‐time contamination source identification algorithms.

Select this Article		Threat Perceptions and Risk Management in Urban Water Supply Schemes Mitthan Lal Kansal, Professor and Aditya Tyagi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)54 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objective of an urban water supply scheme (UWSS) is to provide safe and adequate drinking water to the public on sustainable basis. Most of these WSSs are vulnerable to natural hazards like earthquake, cyclone, landslides, and excessive rainfall etc., and the willful physical, chemical, biological, and cyber attacks. While the risk due to natural catastrophes remains high, the risk due to man‐made disasters has also been increasing during the last few decades. Almost every nation is facing the problem of terrorism, as it is impossible to satisfy all sections of society within a state, a country, or a group of countries at global level. In order to express their dis‐satisfaction and anguish, the disillusioned individuals or group of individuals indulge in the terrorist activities targeting the infrastructures so as to create panic among larger section. The events like September 11, 2001, attack on Indian Parliament, religious places, and recent attack of November 26, 2008 in Mumbai (India), and consistent threats of use of chemical & biological weapons in various parts of the world has compelled the researchers and managers to plan the operation and management of water supply schemes from a different perspective as it is one of the most important infrastructure for the sustenance of society. Precautions are required against the physical, chemical, biological, and cyber attacks on water supply systems.

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NETWORK SECURITY 4

Select this Article		Getting More from Your Investment Using Water Security Monitoring Technology for Everyday Operations Dan Kroll ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)55 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Since 9/11 numerous communities have installed multi‐parameter monitoring stations in the distribution system as early warning systems for potential water security threats. These systems have recorded large streams of data relevant to water quality in the distribution systems. In this study data streams from a number of communities are analyzed for pertinent information as to the health and operation of the distribution system. Changes in water quality are correlated with known causes attributable to day‐to‐day operational changes and also anomalous events (pipe bursts, accidental back flows, cross connections, chemical over feeds, treatment plant problems, nitrification events, etc.). Information concerning what action was taken to ameliorate the problem will also be linked to the data for the identified events. We will need to consider databases such as this before we determine the best course of action to ensure our water supplies meet acceptable levels of safety from source to tap.

Select this Article		Modeling a Hydraulic Response to a Contamination Event Terranna Baranowski Haxton and Thomas M. Walski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)56 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In responding to contamination incidents that may occur in a water distribution network, a variety of actions (e.g., public notification and operational changes) can be pursued. A relatively common and effective operational response option utilized by water utilities to address water quality concerns is flushing. The effectiveness of flushing alternatives can be evaluated by modeling the water distribution system dynamics. Two approaches to modeling hydrant flushing as a hydraulic response are examined in this paper: a fixed flushing rate and flow emitters. In addition, the effects of knowing the source location and the expected contamination spread are explored. The paper generally demonstrates that the effectiveness of flushing depends on the accuracy with which the initial contaminant plume location is known. In modeling flushing as a response, use of flow emitters instead of fixed flow to model hydrant discharge should provide a more realistic description of system response to flushing.

Select this Article		Novel, Rapid Molecular‐Based Technique for Detecting Contamination in Drinking Water Distribution Systems Stacia L. Thompson, Ph.D. and Jeanne M. VanBriesen, Ph.D., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)57 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Drinking water distribution systems are vulnerable to biological contamination via many potential intrusion locations; thus, a comprehensive water quality indicator is critical. While previous research has focused on specific pathogen detection using molecular methods, this study seeks to confirm that bacterial indicator classes, specifically, Alpha‐, Beta‐, and Gammaproteobacteria, can be used as a more comprehensive indicator. The system population exhibits temporal variability in response to changes, such as temperature and disinfectant concentration, but this seasonal bacterial diversity study confirms that these indicator classes are a consistent presence in drinking water. Bacterial class‐specific primers were designed to target Alpha‐, Beta‐, and Gammaproteobacteria, and utilized in Quantitative Polymerase Chain Reaction (QPCR) assays to detect surrogate contaminants. Preliminary results indicate that this QPCR‐based approach is a faster, more comprehensive indicator than the culture‐based regulatory technique.

Select this Article		Trajectory Clustering Approach for Reducing Water Quality Event False Alarms Eric Vugrin, Sean A. McKenna, and David Hart ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)58 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Event Detection Systems (EDS) performance is hindered by false alarms that cause unnecessary resource expenditure by the utility and undermine confidence in the EDS operation. Changes in water quality due to operational changes in the utility hydraulics can cause a significant number of false alarms. These changes may occur daily and each instance produces similar changes in the multivariate water quality pattern. Recognizing that patterns of water quality change must be identified, we adapt trajectory clustering as a means of classifying these multivariate patterns. We develop a general approach for dealing with changes in utility operations that impact water quality. This approach uses historical data water quality data from the utility to identify recurring patterns and retains those patterns in a library that can be accessed during online operation. We have implemented this pattern matching capability within CANARY and describe several example applications that demonstrate a decrease in false alarms.

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NETWORK WATER QUALITY ANALYSIS 1

Select this Article		Comparing Single‐ and Multi‐Species Water Quality Modeling Approaches for Assessing Contamination Exposure in Drinking Water Distribution Systems Stephen Klosterman, Sam Hatchett, Regan Murray, James Uber, and Dominic Boccelli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)59 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract New software such as EPANET‐MSX enables water quality models that account for multiple reactive species in the distribution system. This allows for a more complete analysis of network water quality, including processes such as adsorption and biological inactivation by a disinfectant. For each of these reaction processes, three models are presented: single‐specie conservative, single‐specie reactions modeled by wall demand or bulk decay, and multi‐species. The implications of model selection on the resulting exposure to contaminants that undergo these reaction processes are investigated for a hypothetical intentional contamination event and a simple single pipe system.

Select this Article		Real‐Time Valve Operation for Water Quality Improvement in Water Distribution Systems Doo Sun Kang and Kevin Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)60 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In order to maintain water quality in water distribution systems, disinfection is performed by chemical addition. Chlorine, the most commonly used disinfectant, decays over time by reaction with organic materials in the water and produces potential harmful disinfection by‐ products (DBPs). Therefore, it is important to maintain the free chlorine residuals throughout the system within specified limits. Here, optimal valve operation has been combined with booster disinfection for water quality improvement. Valves are operated to alter the flow distribution in the network, prevent isolation of disinfectant and direct disinfectant laden‐water to locations where it is required. A real‐time optimal valve operation and booster disinfection problem is formulated as a single objective optimization approach. The objective is to minimize chlorine injection while maintaining chlorine concentrations and pressures at consumer nodes. The problem is solved using a single objective genetic algorithm. This paper presents the problem formulation methodology and its uniqueness.

Select this Article		Simulation of Particle Transport in Drinking Water Distribution Systems Klaus Ripl and Wolfgang Uhl ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)61 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Particulate matter in drinking water is one important reason for consumer complains due to discoloured water at customer's taps and further secondary effects. To describe transport of this matter, partices were characterised, important occuring mechanisms described respectively abstracted and, based on known basics for dynamic water quality modelling, a software module developed, which will be linked with a pipe modelling software. Thus, water quality in water supply systems may be predicted and pipe fouling can be described. This shall enhance distribution system operation and planning.

Select this Article		WDS Water Quality Parameter Estimation and Uncertainty M. F. K Pasha and K. Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)62 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract During model development and calibration, errors in field measurements propagate to uncertainties in parameter uncertainty. Water distribution water quality models are typically calibrated using tracer test data. Here, we evaluate the uncertainty resulting from the test assuming demands are known exactly and only the wall coefficients are to be estimated. A meta‐heunstic search engine, Shuffled Frog Leaping Algorithm (SFLA) is linked with hydraulic and water quality simulation software EPANET to estimate the pipe wall decay coefficients. A first‐order approximation is applied then to estimate the parameter uncertainty. This methodology is applied on a mid sized example network. Results show that with tracer injection parameter can be accurately estimated. It is also found that parameter estimation can be more accurate if the magnitude of the wall decay coefficients is higher.

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NETWORK WATER QUALITY ANALYSIS 2

Select this Article		A Hybrid Heuristic Search Approach for Contaminant Source Characterization Li Liu, E. Downey Brill, G. (Kumar) Mahinthakumar, and S. Ranji Ranjithan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)63 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The rapid discovery of the contaminant source and its mass loading characteristics in a water distribution system (WDS) is vital for generating an efficient control strategy during a contamination event. Previous work on the Adaptive Dynamic Optimization Technique (ADOPT), which was developed as an Evolution Strategy (ES) based procedure, presents an approach to estimate the source characteristics adaptively, given dynamically updated observation data. Although this simulation‐optimization approach is promising, it is computationally expensive, which poses challenges in the context of real‐time solutions. This paper reports the findings of an investigation that builds upon the prior work by introducing a hybrid heuristic search method for the real‐time characterization of a contaminant source. This new method integrates the ES‐based ADOPT with a logistic regression (LR) analysis and a local improvement method to expedite the convergence and possibly solve the problem quickly. As a prescreening technique, a LR analysis step is performed prior to ADOPT; this step reduces the search space by eliminating unnecessary source nodes as potential source locations. Then, a local search (LS) approach is embedded into some of the algorithmic steps in ADOPT to serve as a postscreening step that potentially speeds up the convergence in localized regions in the solution space. Numerical experiments for the proposed hybrid approach are performed on an example water distribution network, and the results are compared with those of the standard implementation of ADOPT.

Select this Article		Analysis of Model Sensitivity and Uncertainty for Chlorine Transport and Decay in a Water Distribution System W. J. Dawsey, B. S. Minsker, and A. Ostfeld ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)64 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract There are a number of sources of uncertainty in drinking water distribution system modeling. Uncertain parameters include pipe diameters, consumer demands, hydraulic energy loss coefficients, reaction coefficients and others. Understanding the relative importance of these sources of uncertainty can improve the allocation of resources for model refinement and calibration, as well as, aid knowledge inference from monitoring data. This paper presents an analysis of uncertainty and model sensitivity for chlorine transport and decay in a water distribution system. A clustering and global variance‐based sensitivity methodology is proposed to account for spatial inconsistencies found in the results of previous studies of this problem. Results are presented from small and large scalecase studies. This methodology is then used to explore the occurrence of intrusion events in a water distribution system, and the potential to detect such events through online monitoring of chlorine residual concentrations. Noise present in the chlorine monitoring signal has the potential to overwhelm the detection of an upstream intrusion and its associated chlorine demand. Results are presented from simulated intrusion events of varying magnitude and duration.

Select this Article		Characterizing Reactive Contaminant Sources in a Water Distribution System Jitendra Kumar, E. Downey Brill, G Mahinthakumar, and Ranji Ranjithan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)65 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Accurate knowledge of the characteristics of the contamination source during a contamination event is necessary for development of any mitigation and control strategy. Contaminant injected in a system is most likely to be reactive with chlorine; however, it is impractical for water quality monitoring systems to be able to monitor for the presence of all possible contaminants. In any distribution system, chlorine levels and other water quality parameters (pH, conductance, etc.) are routinely monitored to maintain the prescribed disinfection capacity. Any reactive contaminant would affect the chlorine levels resulting in deviations in the expected chlorine levels from those expected under normal operating conditions. Anomalies in the chlorine concentration from that of the expected value can be used as a surrogate to characterize the contaminant source in the system. In the absence of knowing the reactive characteristics of the contaminants, the location of injection, and injection pattern, source identification becomes a difficult problem to solve. Source identification can be posed as an inverse problem. In earlier work authors investigated the effect of the order of reaction kinetics of the contaminant with chlorine and its impact on source identification problem assuming the reaction kinetics to be known. That work is extended to investigate a methodology to address the source identification problem based on chlorine measurements, and the effects of different uncertain contamination conditions. Findings from a range of scenarios will be presented and discussed.

Select this Article		Low Pressure Propagation at Service Lines Juneseok Lee, Vinod K. Lohani, Andrea M. Dietrich, and G. V. Loganathan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)66 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract There is copious evidence indicating intrusion of contaminants into the drinking water pipes through the leaking sections due to low pressure events associated with water hammer phenomenon. In this study, an experimental plumbing rig was designed and implemented that replicates the range of pressures encountered in actual service lines and the plumbing systems. This research addresses how a pressure transient triggered within a house and from municipal systems can impact the service lines with a possible suction effect. This experiment also enabled visualization of the various pressure transient phenomena including gaseous cavitation. It is demonstrated that hydraulic transients triggered from water mains result in low pressures events in service lines which can allow possible intrusion of microbial and chemical contaminants at service lines. Structural integrity of service line and hydraulic integrity at water mains should be maintained to minimize any public health risks.

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NORTH AMERICAN DRINKING WATER INFRASTRUCTURE ASSESSMENT

Select this Article		Drinking Water Infrastructure Assessment: The National Research Council of Canada Perspective Yehuda Kleiner, Balvant Rajani, and Rehan Sadiq ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)67 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The essence of infrastructure asset management and decision‐making on its renewal/rehabilitation is a trade‐off between system performance and cost. System performance criteria for water networks include quality, quantity and reliability, i.e., the water should be safe, with acceptable aesthetics, taste and odour; regular and peak demand (including fire flows) should be met with acceptable pressure and with minimal interruptions. Costs comprise capital investment in system design, installation and renewal, operation and maintenance (energy, materials, labour, monitoring, inspection, testing, repair), and indirect and social costs incurred due to failure (property damage, disruption, illness, etc.). Several challenges need to be overcome in the development of an integrated decision framework for water distribution network. Mechanisms affecting system performance criteria are not all well understood. It is difficult to define and measure performance (which inherently comprises several non‐commensurate and often conflicting criteria), let alone decide what level of performance is acceptable. It is also difficult to calculate the costs involved to achieve a specific level of performance. Substantial spatial and temporal variability is inherent in even a moderate‐size network, and the collection of data on the performance and condition of these buried assets is often difficult and costly. At the National Research Council of Canada we have identified the need to address these issues in a holistic way, and in the last 15 years have been involved in a continual effort, both independently and in collaboration with others, to put the pieces of the puzzle together. Although the state of knowledge has advanced significantly since we started, a lot still needs to be achieved. This paper describes our past and current research activities, views and vision for future activities in the field.

Select this Article		National Mains Failure Database Project Neil S. Grigg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)68 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water main breaks are a serious problem to utilities, and involve high cost as well as social disruption. Mitigating risk of breaks requires utilities to assess data on past failures and predict which mains are most likely to fail. The UK Water Industry Research has developed a National Mains Failure Database and the US Water Research Foundation has arranged for US utilities to participate. The database is being modified for use by US utilities and a pilot effort is scheduled for 2009. After experience with the database is gained, the Water Research Foundation will work with utility participants to modify and facilitate use of the database.

Select this Article		Needs and Trends of the Nation's Water Infrastructure — The Utility Perspective Steven Buchberger, Robert Clark, Walter Grayman, Zhiwei Li, Matthew McCutcheon, and Jeff Yang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)69 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Widespread changes in the climate, demographics, population and economics are expected to impact the quantity, quality and timing of water resources across the globe in the 21^st century. Some of these impacts may affect the performance and sustainability of the Nation's urban water resources infrastructure. In anticipation of these imminent global changes and their impact on the Nation's water infrastructure, the U.S. Environmental Protection Agency is implementing the Water Resources Adaptation Program for Infrastructure (WRAP‐Infrastructure). WRAP seeks to identify and evaluate innovative approaches to improve the planning, design, operation and maintenance of the Nation's water resources infrastructure in the 21^st century. A key question to be addressed by the WRAP program is, “How can the functionality of the Nation's aging water infrastructure be maintained and sustained to protect human health and preserve the environment for future generations in the face of profound global changes?” To help answer this question, a national data collection effort was conducted with water utilities to identify key factors affecting the current and future performance and sustainability of the water resources infrastructure across the US. Over 60 public and private water and wastewater utilities responded to a detailed web‐based questionnaire. Data from this national reconnaissance are reported here.

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WATER USAGE

Select this Article		Combined Energy and Pressure Management in Water Distribution Systems P. Skworcow, H. AbdelMeguid, B. Ulanicki, P. Bounds, and R. Patel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)70 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In this paper a method is proposed for combined energy and pressure management via integration and coordination of pump scheduling with pressure control aspects. The proposed solution involves: formulation of an optimisation problem with the cost function being the total cost of water treatment and pumps energy usage, utilisation of an hydraulic model of the network with pressure dependent leakage, and inclusion of a PRV model with the PRV set‐points included as a set of decision variables. Such problem formulation led to the optimizer attempting to reduce both energy usage and leakage. The developed algorithm has been integrated into a modelling, simulation and optimisation environment called FINESSE. The case study selected is a major water supply network, being part of Yorkshire Water Services, with a total average demand of 400 l/s.

Select this Article		Design of Dual Water Supply Systems R. Chee, D. S. Kang, K. Lansey, and C. Y. Choi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)71 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water scarcity is causing major concerns throughout the world, especially in arid regions where cities are growing rapidly and are depleting groundwater reserves faster than they can be recharged. The southwestern U.S., Arizona and Nevada in particular, are experiencing the large growth rates with limited water resources and no new sources available. In effort to reduce the amount of water being consumed by people, new engineering technologies are being explored. Water reuse is becoming recognized as the last untapped water resource. However, little research has been conducted on effectively distributing that water to user. In particular, distribution of reclaimed water through a parallel pipe networks system to homes or dual water supply system has not been considered. Existing distribution systems deliver water via a single system. Meeting flow and pressure requirements for fire conditions are driving factors in designing water distribution systems. Minimum regulatory pipe diameters of six to eight inches are common in most systems and can lead to reduced water quality. The goal of a parallel system is to maximize the usage of reclaimed water. By distributing non‐potable water through a separate line to meet non‐sanitary uses (i.e., outdoor, fireflow, and toilet flushing), the need for potable water can be greatly reduced. Separating these demands from the potable system can reduce the potable system pipe sizes, improve water quality and reduce the overall cost of the water distribution system. Some cities in the southwestern U.S. have already implemented this new system in some residential areas through a non‐potable “purple pipe” system. However, the efficiency of these new systems has not been thoroughly examined. This paper will focuses on the design of dual systems by using an optimization algorithm linked to EPANET (USEPA, 2000) via the EPANET toolkit to determine the optimal least‐cost design of dual piping systems.

Select this Article		Modeling Domestic Water Demand on a Suburb Level M. L. Griffioen, J. E. van Zyl, and A. S. le Roux ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)72 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In this study it was assumed that a suburb provides a good basis for grouping water demands, and that it is adequate to design for the average suburb AAD (annual average demand). A database on measured domestic water demands was used to determine the average AAD for a large number of suburbs in South Africa, and this data was further linked to sensus and climate data. The combined data set was then subjected to various regression analyses, and a method was developed to compare these models. This method may assist with determining suitable design guidelines for suburb AAD in future.

Select this Article		Preliminary Spatial‐Temporal Statistical Analysis of Hourly Water Demand at Household Level Ernesto Arandia‐Perez, James G. Uber, Feng Shang, Dominic L. Boccelli, Robert Janke, David Hartman, and Yeongho Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)73 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A methodology for modeling time series of hourly urban water use is presented based on separating the data into three components: trend, seasonality, and autocorrelation. Each component is represented by a model whose parameters are estimated. The series is transformed by removing each of the three components and the last transformation produces only a random error series. In the process of identifying the most suitable model for the autocorrelation component of the series, a large number of alternative autoregressive moving average (ARMA) models are assessed in terms of statistics that measure accuracy, parsimony, and randomness of the residuals. Hourly spatially aggregated water use in Cincinnati, Ohio, during the month of October, 2008 is modeled as an example. The model explains approximately 50% of the variance of this series, divided as trend (8.28%), seasonality (11.51%), and autocorrelation (29.94%). The methodology will be applied in a future study of a large data set of individual service connection hourly demand series, spatially aggregated under different schemes.

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6TH URBAN WATERSHED MANAGEMENT SYMPOSIUM

Select this Article		10,000 Rain Gardens, One Green Region Tom Jacobs ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)74 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The adoption of a broadly stated sustainability framework as the basis for the Overflow Control Plan (OCP) in Kansas City, Missouri is both extraordinary, and reflective of the community's commitment to become America's Green Region. The plan positions the city's wet weather program as a tool to catalyze more integrated water resource management at the neighborhood and watershed scales, and as a strategic initiative that supports sustainable development efforts at the metropolitan scale.

Select this Article		A Level Spreader — Vegetated Buffer System for Urban Stormwater Management Ryan J. Winston, E.I. and William F. Hunt, P.E., Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)75 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Vegetated filter strips (VFS) have been used to remove pollutants from contributing agricultural watersheds for decades. In order to improve effectiveness of vegetated buffers, level spreaders have been employed to distribute flow evenly across the length of the upstream end of the buffer. In North Carolina, level spreader‐ VFS systems are now gaining acceptance as a stormwater BMP for urbanized watersheds, as it promotes infiltration and reduces impervious surfaces, two tenets of Low Impact Development. A field study of four level spreader — vegetated filter strip systems was conducted at two urban watersheds in Louisburg and Apex, NC. At each site, stormwater was routed proportionately over two 13 ft long level spreaders, one draining to a 25 ft wide grassed buffer, the other to a 50 ft wide, half grassed, half forested buffer. Flow rates and flow volumes were measured at the inlet and outlets of the system. Composite, flow‐weighted water quality samples were collected at the inlet and outlet of the system and analyzed for TKN, NO₃+NO₂, TN, NH₃ TP, Orthophosphate, and TSS. The buffers promoted infiltration, which resulted in a substantial decrease in flow volume and peak flow rate between the inlet and outlet of the system. To date, 46 storm events have been monitored for hydrology in Louisburg, NC. Flow volume was reduced by an average of 83% and 80% for the 25 ft and 50 ft wide buffers, respectively. These buffers also reduced peak flow rate by an average of 86% and 83%, respectively. These results show that a level spreader − vegetated filter strip system can effectively reduce the hydrologic impacts of impervious surfaces. Water quality monitoring has been ongoing since March, 2008, with 19 and 20 storms monitored for Apex and Louisburg, respectively. Reductions in event mean concentrations for all buffer treatments occurred for TKN, TN, and TSS, while the other pollutants studied had mixed results. Because of the large reduction in volume due to infiltration, these BMPs provide a large reduction in mass of pollutants. The median percent mass removal for the Louisburg buffers was greater than 74% for all but one water quality constituent studied. A level spreader is relatively (1) easy to install, (2) inexpensive, and (3) requires little maintenance. Carefully selected and designed level spreader − vegetated buffer systems can be an effective method of controlling stormwater flow and its associated pollutants in small urban watersheds.

Select this Article		A New Methodology to Evaluate Pollutant Removal of Gross Solids Separation Devices D. P. Smith ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)76 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Gross Solids are a set of stormwater components that includes large organic and inorganic materials, litter and trash, and relatively large suspended sediments. A common characteristic of Gross Solids is that they are not fully accounted for in BMP monitoring protocols that employ only automatic sampling devices for collection of water column samples. A methodology is presented that provides a quantitative framework for incorporating Gross Solids into estimates of the pollutant removal effectiveness of Gross Solids Separation Devices. Illustration of the methodology using monitoring data for a full scale Nutrient Separating Baffle Box demonstrates the significance of including Gross Solids in estimates of pollutant removal effectiveness. The resulting performance analysis would not be possible using traditional monitoring approaches.

Select this Article		A simplified model of Combined Sewer Overflows to estimate event driven enteric pathogen concentrations in drinking water sources Rishab Mahajan, James Uber, and Joseph Eisenberg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)77 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Raw sewage discharges from Combined Sewer Overflows(CSO's) during rainfall can severely impact drinking water quality. Drinking water risk assessment studies in the past have not adequately captured the event driven temporal fluctuations in source water quality. This is despite the knowledge that fecal contamination of source waters is impacted by rainfall and long‐term accumulated risks are affected by event driven concentration peaks. This paper presents a simple methodology to estimate the enteric pathogen loadings into the receiving water as a result of combined sewer overflows. The proposed methodology is more suitable for risk assessment studies to formulate policies for public health protection.

Select this Article		Source Control: The Solution to Stormwater Pollution Michael A. Ports, P.E., PH, D. WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)78 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Another name for source control is pollution prevention. In almost every case, it is easier and cheaper to prevent pollution from occurring in the first place than it is to collect and treat it after the fact. Municipal stormwater managers throughout the United States are coming to grips with the fact that municipal stormwater management requires significant effort and resources and raises numerous legal and financial issues and concerns. More emphasis on source control has the potential to improve system reliability, reduce costs, improve equity, reduce liabilities, as well as improve water quality. When Phase II of the municipal separate storm sewer system permit program under the National Pollutant Discharge Elimination System began, most stormwater managers relied primarily on end of pipe treatment to meet their goals. Under the Clean Water Act, the United States learned that end of pipe treatments are effective in reducing pollutant loads discharging from municipal and industrial wastewater plants. For example, from 1968 through 1996, municipal wastewater treatment plants reduced BOD entering receiving waters by 45 percent in spite of a significant increase in population served (USEPA 2000). Thus it was no surprise that most municipalities formulated and began their stormwater programs based upon the assumption that, if end of pipe treatment worked so well with municipal sewage, then end of pipe treatment should work with urban stormwater. Experience, unfortunately, has demonstrated that this is not the case. The flow and composition of municipal waste generally is well known and predictable. Thus, it is relatively easy to design and operate cost effective treatment systems. However, the flow and composition of urban stormwater is highly variable, both spatially and temporally. Municipal wastewater treatment plants are sophisticated, energy intensive operations equipped with elaborate control systems. On the other hand, end of pipe urban stormwater treatments are relatively simple structures with primitive, if any, operational control. At a modern municipal wastewater treatment plant, BOD removal usually reaches 95 percent or more and nutrient removal rates may exceed 85 percent. Removal rates for BOD at a typical structural stormwater BMP may vary by storm from as little as 16 to as much as 93 percent (Strecker, Quigly, and Urbonas 2000). Removal rates vary nearly as much from BMP to BMP regardless of type, size, location, and climate.

Select this Article		A Student‐Led Effort to Assess the Effect of Urban Runoff on Potter Lake. England Porter, John Kenny, Edward Peltier, and C. Bryan Young ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)79 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Potter Lake is a small water body on the University of Kansas campus. Eutrophication and sedimentation are both significant water quality issues for this system. As stormwater runoff provides as significant portion of the total inflow to this system, student‐led efforts to develop a restoration and management plan for Potter Lake, have focused on assessing the quantity and quality of this runoff. A water balance model for the Potter Lake watershed was developed using climatological data and watershed characteristics. Runoff samples from four locations were collected for water quality analysis using passive collection bottles suspended in existing storm sewers. Water quality analysis indicates that runoff from Jayhawk Boulevard contributes a disproportionate amount of the total loading of suspended solids and phosphorus, particularly during heavy storms when soils are mobilized from open areas along this street. Improving the water quality in Potter Lake may require treatment of this stormwater prior to discharge into the lake.

Select this Article		A Tool for the Performance Assessment of Hydrodynamic Separators Omid Mohseni, Janna M. Kieffer, and Jennifer A. Koehler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)80 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Hydrodynamic separators are stormwater treatment devices with small footprints used for removing suspended sediments from stormwater runoff in urban areas. These devices have been tested by different laboratories under a set of specific conditions, e.g. a limited number of flow rates, under a specific water temperature (fluid viscosity), a specific particle size distribution and particle specific gravity. However, the question ahead of the primary users of these devices, i.e. cities, counties and other local government agencies and large retailers is: “How well do these devices remove suspended sediment from our stormwater runoff?” To address this question a tool has been developed to simulate continuous loading from small drainage basins in urban areas and to simulate the response of these devices in removing the suspended load from stormwater runoff. The tool is comprised of a hydrologic model and a generic device response model. The hydrologic model utilizes the SCS curve number method and the SCS unit hydrograph to simulate runoff. The input data into the hydrologic model are the drainage basin characteristics and 10 years of 15‐minute precipitation data. The generic device response model utilizes the removal efficiency performance functions developed from the laboratory testing conducted on hydrodynamic separators. The input data for the device response model are 10 years of daily air temperature data, the particle size distribution, specific gravity, and influent concentration of suspended sediments in stormwater runoff. The tool has been applied to four small urban drainage basins in Minnetonka, MN using four hydrodynamic separators as stormwater treatment devices. The results of continuous simulation were compared to the performance assessment of the devices under 1‐year and 2‐year frequency storm events to determine if an event‐based simulation is adequate to assess the performance of these devices.

Select this Article		Accurate Sampling of Suspended Solids Gregory P. DeGroot, John S. Gulliver, and Omid Mohseni ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)81 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Automatic samplers have difficulty with sampling accuracy of inorganic particles larger than silt. The samples are generally at higher concentrations than the true mean concentration in the flow, because of the settling velocity of the particles and the sampling near the bottom of the flow. The vertical mixing is insufficient to overcome the settling of coarse silts and sands. A sampling methodology has been developed to accurately sample suspended solids in stormwater. This methodology is evaluated for its effectiveness, as well as its ability to be transferred to engineering and environmental practice. Emphasis is being placed on developing a methodology which is cost‐effective, allowing a method of particle sampling which fits specific users and their projects.

Select this Article		An Evaluation of Stormwater Wetlands in Series J. M. Hathaway and W. F. Hunt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)82 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Retrofit BMPs are an important tool for achieving water quality goals in urban watersheds, providing treatment to areas not originally developed with stormwater management practices. One such BMP was installed and monitored in Mooresville, N.C. The system includes three wetlands built “in‐series” to treat runoff from a highly impervious 30 acre watershed. The configuration of the wetlands allowed monitoring of water quality parameters at the outlet of each of the three stormwater wetlands. The results of this study indicate that water quality improvement for a number of pollutants experiences diminishing returns as it passes through the three wetland cells. For total suspended solids (TSS), approximately 95% of the total concentration reduction took place in the first wetland cell despite it only comprising 60% of the total surface area of the system. Analysis of the effluent concentrations of the first wetland cell indicates that undersized wetlands (roughly 1.5% of the contributing watershed in this case) may still contribute to water quality improvements in urban watersheds. Thus, retrofit BMPs may be desirable even in circumstances when they cannot be sized appropriately for the contributing watershed.

Select this Article		An Innovative Approach for Modeling Large Urban Hydrologic Systems J. P. Cantone and A. R. Schmidt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)83 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The dynamics of the urban landscape are ever changing. As the population grows, urban sprawl gathers momentum and the path for a drop of rainfall changes complexion. The physical processes involved from when rain falls until when it reaches a treatment plant or waterway are highly non‐linear. In larger urban catchments, these non‐linearities have largely been ignored and linearized through development of lumped or semi‐distributed models. This linearization is often used to overcome the sheer size and complexity of the urban catchments. The answer to the question of how much network complexity should be included in a model has been pre‐empted by the application of conduit skeletonization and subcatchment aggregation. These simplification techniques are not without their dangers and may introduce bias into the predicted hydrographs. This paper provides a review of modeling approaches that are typically undertaken in modeling large urban catchments, highlighting their advantages and disadvantages. The majority of the approaches involve the application of hydrologic models that require calibration and significant knowledge of hydrologic inputs. In many cases the assessment of existing urban hydrologic systems is hindered by the absence of input data and/or calibration data. With this in mind, an innovative approach to modeling large urban hydrologic systems is presented. This approach builds on the fundamentals of the geomorphologic instantaneous unit hydrograph (GIUH) that was developed by Rodriguez‐Iturbe and Valdes in 1979, which has been successfully applied to natural watersheds over the past three decades. Application of GIUH has evolved such that it can be applied to ungauged natural watersheds with knowledge of as little as the watershed area and layout of the stream network. The approach proposed in this research, in a similar manner, uses the morphology of the sewer system to route flow through the network. Excess rainfall is determined using the Green and Ampt method based on the physical characteristics of the underlying soils. The kinematic wave approach is used, in conjunction with stochastically generated parameters describing relevant subcatchment and sewer characteristics to establish probability distribution functions (PDF) for overland (both pervious and impervious) and sewer travel times. The PDF's of the travel time and excess rainfall are convoluted to generate an outflow hydrograph. This approach maintains the non‐linearity of the physical processes in highly urbanized catchments and allows model development in the absence of detailed input and calibration data. Through application of this approach an improved understanding of the physical process can be achieved.

Select this Article		Analysis of Bioretention Media Specifications and Relationships to Overall Performance Sean W. O'Neill and Allen P. Davis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)84 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bioretention performance specifications differ greatly among jurisdictions. Selected specifications from Prince George's County, MD; MDE; Fairfax County, VA; VDCR; and DNREC are compared for hydrologic management effectiveness, pollutant removal efficiency, construction and maintenance costs, and constructability. Optimal construction and performance requirements are summarized, with the necessity of variable criteria for differing pollutants acknowledged. Specification recommendations are tailored accordingly. Shallow cells with a surface mulch layer are recommended for removal of metals and particulate pollutants. Deeper cells having thick vegetative cover instead of top dressing are recommended for nutrient removal. Additionally, aluminum water treatment residual as a media amendment for phosphorus removal is recommended. This combined with an anoxic saturated zone for nitrogen removal may prove ideal for combined nitrogen and phosphorus removal.

Select this Article		Analyzing the Impacts of a Retrofit Detention Basin Flow Control Strategy on Biodiversity in an Urban Stream System Natalie A. Postel, P.E., M. ASCE, Christine A. Pomeroy, Ph.D., P.E., M. ASCE, Tom A. Jacobs, P.E., M. ASCE, and Elangovan Karuppasamy, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)85 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Protecting biological diversity of a stream system while supporting development and growth is critical to sustainability. To this end, the City of Lenexa, Kansas has embarked on the Eastern Lenexa Detention Study. The study focuses on 1017 acres (1.6 sq. mi.) of Little Mill Creek watershed in Lenexa, Kansas, a Kansas City suburb. Little Mill Creek drains to Mill Creek, which is listed as an impaired water body under section 303(d) of the Clean Water Act. Water quality impairment parameters include chloride, fecal coliform bacteria, and biology. This study examined whether modifying 16 existing detention basins to capture and detain smaller storm events would significantly increase biological diversity and reduce erosion potential within Little Mill Creek. The study used biological data and discharge measurements collected at 11 sites within and near Little Mill Creek to develop linkages among hydrologic and biologic metrics.

Select this Article		Are Rational C Values Too Low? C. B. Young, B. M. McEnroe, and A. C. Rome ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)86 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents empirically derived estimates of the Rational C runoff coefficient for rural watersheds in Kansas. The C values vary with location (there is an east‐west trend) and recurrence interval. The C values derived for western Kansas are in line with values commonly assumed for rural watersheds. However, the C values computed for eastern Kansas are much higher than the values found in many hydrology textbooks and design guidelines. The median Rational C values for the watersheds in eastern Kansas are 0.32, 0.63, and 0.97 for the 2‐, 10‐, and 100‐year recurrence intervals.

Select this Article		Assessing Hydrodynamic Separators under High Water Flow Conditions David Saddoris, Omid Mohseni, and John Gulliver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)87 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Underground hydrodynamic separators are widely used in urban areas for removal of suspended solids and floatables from stormwater due to limited land availability for the installation of above ground stormwater best management practices (BMPs). Hydrodynamic separators are sized for applications based on design runoff from the drainage basins that they serve. However, during less frequent storm events, device maximum treatment rates are exceeded and previously captured sediments can be scoured and washed out of these devices. A methodology has been developed to assess sediment retention in hydrodynamic separators under water flow rates exceeding their maximum design treatment rates. This new testing protocol has been used in controlled field and laboratory tests on full‐scale commercial devices under high water flow conditions to determine sediment retention performance. Application of this work is primarily to establish the frequency of required cleaning for installed devices.

Select this Article		Assessment of Standard Sumps for Stormwater Treatment Adam Howard, Omid Mohseni, John Gulliver, and Heinz Stefan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)88 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Although proprietary devices for the treatment of stormwater are used in many urban areas as best management practices (BMPs), their cost has prompted the Minnesota Department of Transportation (DOT) to consider the use of standard sumps to meet stormwater quality goals. However, no data on the effectiveness of sediment removal and proper operation of the sumps exist. Such data is necessary for standard sumps to be considered as a stormwater pretreatment device in Storm Water Pollution Prevention Program regulations.

Select this Article		Bayesian Load Duration Curves for Bacterial Total Maximum Daily Loads: Urban Case Study Mary Schoen, Mitchell Small, and Jeanne VanBriesen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)89 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A Bayesian load duration curve approach is developed to estimate indicator bacterial load reductions for a small, urban watershed with stormwater and animal inputs. The Bayesian load duration curve approach uses the truncated bivariate normal probability distribution to predict flow, in‐stream bacterial concentration, and the resulting load for a specified number of flow conditions. Using non‐informative priors, the Bayesian approach propagates the uncertainty resulting from the natural variability in observed concentrations through to the predicted in‐stream indicator bacterial concentration and load. Using the best estimate 90^th percentile in‐stream loads, the Bayesian method predicts indicator bacterial load reductions ranging between 68% for low flows and 99.9% for high flows. The predicted distributions of in‐stream bacterial concentration are then compared pre‐ and post‐implementation of stormwater filtration. The pre‐implementation distribution of in‐stream indicator bacterial concentration demonstrates that the stream exceeds the standard of 235 cfu/100ml E. coli 76.1% of the time during the recreational season with a 95% credible interval CI(74.6, 78.0). The post‐implementation distribution of indicator bacterial concentration predicts that the concentration of indicator bacteria exceeds the limit set by the water quality standard 72.4% CI(70.6, 74.3). Alternatively, the Bayesian model is then used to predict in‐stream concentration post‐implementation of an aggressive ultra‐violet disinfection process.

Select this Article		Bioretention/Bioinfiltration Performance in the Mid‐Atlantic R. A. Brown, W. F. Hunt, A. P. Davis, R. G. Traver, and J. M. Olszewski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)90 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Researchers in Maryland, North Carolina, and Pennsylvania have been conducting parallel bioretention/bioinfiltration research since fall 2007. Various designs have been tested including those that rely on underdrains, have internal water storage (IWS) layers, or are underdrain‐free. The cells provide a range of watershed practice size ratios and employ a variety of land covers. Researchers are pooling water quantity and quality data to help create new design standards. Initial results from the shared data will be presented, with specific attention to bioretention design parameters that control flow modification and water quality improvement. Two bioretention cells of varying vegetative cover are being monitored in Rocky Mount, NC. This site is located in the upper coastal plain with sandy in‐situ soils. These cells were designed with a 0.9 m media depth and a 0.6 m deep internal water storage (IWS) layer. Another bioretention cell is being monitored in Silver Spring, MD. It was constructed with a 0.9 m media depth and a 0.3 m pooling depth. Finally, there are two bioinfiltration cells being monitored in Villanova, PA. The first is the “Traffic Island” bioinfiltration cell, which has been monitored since 2003. The bowl is only designed for 1.2 cm over the impervious surface, yet overflow rarely occurs for events less than 5.1 cm. The site had groundwater wells installed in 2007 and is the subject of an ongoing study on the groundwater effects. The second site has only been monitored for approximately six months. Cumulatively, the four bioretention cells extensively examined have dramatically reduced outflow volumes, completely assimilating all events less than 1.2 cm — and in some designs much greater events. By aggregating the data, runoff reduction by bioretention can be profound.

Select this Article		Breaking down the Barriers to Low Impact Development in Colorado Andrew Earles, Ph.D., P.E., D.WRE, Derek Rapp, P.E., CPESC, Jane Clary, CPESC, and Janice Lopitz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)91 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The KICP study has included development of a questionnaire that has been circulated to municipal staff, engineers, developers and other parties involved in the development review and approval process. As a part of the study, KICP has developed a checklist for use by developers and by municipal staff reviewing plans to identify potential opportunities for LID and to be sure that the relevant factors that can lead to success or failure of a LID approach are considered in the development review process. Checklists were applied to several proposed development projects to refine the checklists and to identify additional barriers to LID based on “real world” projects. This paper presents the results of the KICP study. Major components of the study discussed in this paper included the following: 1. Identification of potential barriers to design and implementation of LID practices. This was accomplished through a series of several meetings in which participants identified barriers they had encountered and through interviews with planners, engineers and developers. 2. Development of questionnaire based on barriers identified by the group. The questionnaire was distributed to municipal staff involved in KICP as well as to engineers and developers working in the KICP watersheds. The Homebuilders Association (HBA) of Metropolitan Denver also distributed the questionnaire to members of its water quality committee. 3. Identification of conceptual level strategies to address barriers identified as a part of the study.

Select this Article		Challenges in Attaining Recreational Stream Standards for Bacteria: Setting Realistic Expectations for Management Policies and BMPs Jane Clary, Jonathan Jones, P.E., D.WRE, and Ben Urbonas, P.E., D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)92 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Attainment of U.S. Environmental Protection Agency (EPA) recreational water quality criteria and state water quality standards for bacteria presents significant challenges to water resource managers in communities throughout the U.S. From a regulatory perspective, many communities are faced with Total Maximum Daily Loads (TMDLs) for bacteria, typically for either E. coli or fecal coliform. For local governments responsible for National Pollutant Discharge Elimination System (NPDES) Municipal Separate Stormwater (MS4) permits, this issue can be particularly challenging and many questions arise with regard to whether stormwater best management practices (BMPs) can reduce bacteria in stormwater runoff. Many valid questions exist regarding how attainable current stream standards are and what measures are truly meaningful in reducing bacteria in streams and in development of meaningful TMDLs. This paper provides a synopsis of Best Management Practice (BMP) performance data provided for bacteria in the International Stormwater BMP Database and discusses implications of these findings for stormwater managers. Findings from analysis of these data are used to provide some recommendations regarding the types of efforts that are expected to provide meaningful results in terms of water quality management policy and bacteria reduction in stormwater and receiving waters. Implications for development of TMDLs with the potential to provide real improvement of water quality is also discussed.

Select this Article		Characterizing Water Inputs to Catchments in the Santa Monica Mountains with δ18O and δD W. Hu, B. Hibbs, and R. Bugarin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)93 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water inputs to Santa Monica Mountains National Recreation Area (SMMNRA) watersheds include local precipitation, runoff of imported water and treated wastewater derived from imported water. Imported water from northern California is isotopically distinct from southern California precipitation. This contrast allows source flow differentiation. To determine the relative contributions of water sources to creeks and streams in the SMMNRA, stable water isotopes [δ18O, δD] are used. Sampling of rainwater, stream water, tap water and treated wastewater was done from January through December 2008. Analysis includes a focused study of McCoy Creek. Results show tap water and treated wastewater to be fairly reliable end members and local precipitation to be unreliable as an end member. The isotopic signatures of McCoy Creek samples appear to be affected either by evaporation or changes in imported waters' isotopic signatures.

Select this Article		Clark County Regional Flood Control District Arc Hydro (CCRFCD Arc Hydro): Toward on‐going Stormwater Master Planning Stephen Bourne, P.E., Kevin Eubanks, P.E., CFM, Harshal Desai, P.E., CFM, and Brian Rowley, P.E., CFM ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)94 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Las Vegas Valley represents an extreme hydrologic condition in that its high density population must manage discrete but very heavy rainfall events in an erstwhile arid climate. The runoff from these events is routed by way of an elaborate existing and proposed flood control facility system which is composed of washes, channels, storm drains and detention basins. First developed in 1986, the CCRFCD Master Plan has been an excellent planning document for major flood control facilities within the Las Vegas Valley. Currently, the CCRFCD uses a periodic (every 5 years) stormwater infrastructure master plan update process, which requires hydrologic modeling to understand system response to major storm events. Over time, the Master Plan Update (MPU) has evolved into a technical tool for guiding local governmental agencies and private consultants in the development of both public and private property. This paper will describe the design and on‐going development of an Arc Hydro based GIS database for the Las Vegas Valley. This database will provide the geographic and technological foundation for regional hydrologic modeling, efficient permitting, and emergency response modeling. Benefits of moving to this standard include 1) an in‐built geometric network that can be used for delineation of drainage area and stream tracing, 2) the integration of existing CCRFCD GIS and hydrologic modeling data into a single database, and 3) making accessible the broad variety of tools that already exist for the Arc Hydro platform.

Select this Article		Codorus Creek Restoration — A Case Study for the Chesapeake Bay Matthew P. Hoch, Ph.D., Christina Y. S. Siu, Shirley E. Clark, Ph.D., P.E., D.WRE, M. ASCE, and Katherine H. Baker, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)95 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Healthy streams have the physical characteristics and chemical water quality to support healthy and diverse populations of organisms. The Codorus Creek, a tributary to the Susquehanna River, which eventually drains to the Chesapeake Bay, is being restored in several locations. Penn State University (York and Harrisburg campuses) is evaluating the effectiveness of the state‐funded restoration activities. We examine the current pollutant loadings of two branches of this stream in conjunction with land use practices, particularly agriculture and wastewater treatment plants. Fish, macroinvertebrates, and periphyton are routinely sampled. Streamwater sampling for water chemistry analyses occurs during both baseflow and storm event conditions. Restored sites are being compared to both impaired and control sites to determine whether restoration has any significant reduction in a pollutant's load. Preliminary results indicate that the southern branch has greater impairment than the eastern branch. The southern branch impaired site showed greater annual mean loads of total nitrogen and total phosphorus, a macroinvertebrate community dominated by pollution tolerant organisms, and a greater number of fish with parasitic diseases. All sources contributing to the total nitrogen load to Codorus Creek have not been identified. Although restoration activities may decrease pollutant loads, such as as suspended solids, restoration is not believed to be effective in decreasing nitrogen loads. Nitrogen is found more readily in the aqueous phase (streamwater) rather than adsorbed to sediment particles. Therefore, more effective ways to remove nitrogen in water is to decrease or eliminate the source or to treat the streamwater directly. Further monitoring and comparison of restored sites to control and impaired sites are needed. In addition, future work on the toxicity of the legacy sediments has been proposed.

Select this Article		Combining GIS, BMP Performance, and Strategic Planning to Support Water Quality Implementation Planning Ken Susilo, P.E., D.WRE, CPSWQ, Marc Leisenring, P.E., and Eric Strecker, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)96 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Numerous efforts to improve storm water quality on a watershed‐wide basis have lacked a reproducible, transparent, methodical approach to optimize the selection and implementation of structural Best Management Practices (BMPs) to meet receiving water quality goals. For urban stormwater retrofit projects, structural BMPs are primarily selected in an opportunistic, site‐specific fashion, focusing on one or a few pollutants, stakeholder inputs, or local funding availability. As geographic information systems (GIS) technologies improve, computing power increases, and pollutant loading and treatment efficiency datasets become more robust there is an opportunity to improve watershed‐based implementation planning efforts. The authors have developed methods to prioritize water quality improvement needs and identify structural BMP opportunities on a watershed scale to maximize the return on investment for improved water quality. Opportunity evaluation considers property ownership and the potential for retrofitting to achieve multiple benefits, such as water quality, aesthetics, recreation, and habitat. It is recognized that different types of land parcels typically have different types of opportunities and constraints. BMP opportunities can be regional or distributed in nature depending on the land use, size, and location of the public parcel, among other things. By utilizing GIS‐based parcel and land use information in the context of water quality need, potential opportunities, and constraints, as well as BMP unit processes and performance data, watershed‐wide benefits of BMP implementation can be assessed.

Select this Article		Considerations, Opportunities, and Strategies for Infiltration Stormwater BMPs Ken Susilo, P.E., D.WRE, CPSWQ, Neven Matasovic, Ph.D., P.E., GE, and Ronald S. Johnson, P.E., GE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)97 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Infiltration as a Best Management Practice (BMP) is strongly encouraged by many who are focused on water quality, water resources, and regulatory compliance. It is often considered the ideal solution that solves multiple problems. Many practicing engineers, designers, and project approvers however, are concerned about the widespread implementation of infiltration measures, and have initiated restrictive conditions that significantly limit their use. This paper discusses benefits and considerations that should be made when proposing infiltration BMPs, offers potential methods to meet what can be limiting site conditions, and discusses recent applied research/design efforts that been initiated in southern California. Infiltration has numerous potential benefits, particularly in urbanized watersheds. Infiltration BMPs when implemented properly can lead to a) restoration of natural hydrologic cycles; b) mitigation of the degradation of creeks; c) management of water resources; and d) comprehensive watershed ‐wide water quality improvement. There are, however, numerous design considerations that should be evaluated when proposing infiltration BMPs. These include a) soil type/infiltration capacity; b) groundwater;, c) pre‐existing contamination; d) design and hydraulic issues; e) long‐term issues such as groundwater mounding and ground settlement; f) introduction of geological hazards such as landsliding, soil liquefaction and their impacts; and i) other issues such as mold and waterproofing that may result from the presence of wet soil. While many of these considerations can be fatal flaws, in some cases innovative engineering approaches can be implemented to increase the viability of infiltration, particularly where choice of satisfactory alternatives is limited. This paper explores some of these methods and impacts related to implementation of these methods. In addition, some recently initiated projects that are expected to contribute to the body of knowledge regarding infiltration concerns and opportunities, and are worthy of further examination and tracking are outlined.

Select this Article		Construction and Performance of Bioretention Cells G. O. Brown, R. A. Chavez, D. E. Storm, and M. D. Smolen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)98 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bioretention cell are gaining popularity as a stormwater best management practice (BMP). This can be largely attributed to the fact that they present a broad range of potential benefits such as decreased runoff, thermal attenuation, aesthetics and improved water quality through various physical, chemical and biological processes. Ten prototype cells were constructed in Oklahoma as part of an ongoing demonstration project. The cells ranged in size from 19 m³ to 435 m³, and the filter media incorporated fly ash to enhance phosphorus and heavy metal retention. Eight of the cells were installed in Grove, Oklahoma by a contractor, while the other two were constructed in Stillwater by the authors. This paper discusses engineering considerations, general design procedures, cell specifications, construction costs and issues that arose during construction.

Select this Article		Cost Estimating Tools for Low‐Impact Development Best Management Practices C. Dasch Houdeshel, Christine A. Pomeroy, Ph.D., P.E. M. ASCE, Lisa Hair, and Robert Goo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)99 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The stormwater community has a critical need for evaluating the life‐cycle costs of Low‐Impact Development (LID) Best Management Practices (BMPs) as part of encouraging communities to incorporate LID. Great effort has gone towards demonstrating that LID BMP techniques can mediate negative stormwater effects including increased discharge volume from impervious surfaces and pollution loading as water travels through urban settings. However, LID BMPs must be proven to be cost effective as well as technically functional. The current suite of cost tools available through the Water Environment Research Federation (WERF) is being expanded to include vegetative roofs, rainwater catchment systems, and bioretention facilities. These tools provide a detailed framework to facilitate cost estimation for capital costs, operation and maintenance costs, and life‐cycle net present value. The tools can serve as a format for cost reporting for past, current and future projects, and also provide users with planning‐level cost estimates. The cost tool includes both a parametric cost estimation to demonstrate approximate cost per drainage area, and a line‐itemized engineer's cost estimation tool. The line‐item engineer's estimate allows the user to customize their project, while exposing the user to an extensive list of potential costs and opportunities to maximize stormwater management value. The use of this cost tool will enable consistent reporting of cost data on LID BMPs, so that users will be able determine the cost of each component of the project, both in materials and in planning and design. The standard format will also improve the ease of preparing cost estimates, since the necessary line items are broken out for consideration. Creating an understanding of the life‐cycle cost benefits of LID will lead to more use of LID and green infrastructure in development and redevelopment.

Select this Article		Data Reporting Guidelines for Certification of Manufactured Stormwater BMPs: Part II Robert M. Roseen, M. ASCE, Ernie Carrasco, Yuan Cheng, Bill Hunt, Charlene Johnston, Jim Mailloux, Walt Stein, and Tim Williams ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)100 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Data Reporting guidelines presented here were developed as part of the ASCE/EWRI Task Committee on Guidelines for Certification of Manufactured Stormwater BMPs. This work is the collaboration of the Stormwater Infrastructure Committee of EWRI's Water, Wastewater, and Stormwater Council (WWSC) and the Wet Weather Flow Technology Committee of the Urban Water Resources Research Council (UWRRC). These guidelines were developed by review of the major manufactured treatment device certification protocol requirements drawing primarily from the Technology Assessment Protocol‐Ecology (TAPE) and the Technology Assessment Reciprocity Partnership (TARP). These reporting guidelines have been broadened to support the International Stormwater Best Management Practices (BMP) Database. With the increasing need for the field testing of proprietary devices comes the importance of consistent data reporting guidelines to be used when reporting to regulatory agencies or designers. The need for standardized reporting is underscored by the tremendous impact the range of testing factors can have upon testing results. These factors include the testing environment, experimental design, testing methodologies, statistical analysis, and data presentation. The need for consistency is underscored by the complex influence these factors have upon performance results. A clear and consistent data reporting approach can ensure that these biases are minimized, well understood, and that representative field testing can be effectively evaluated by the regulatory agency. A consistent reporting format is also needed to aid vendors to efficiently navigate the complicated application process for device certification. Finally, an independent third‐party is needed to either conduct or review the testing to ensure testing impartiality. The committee membership includes stakeholders from the regulatory, academic, manufacturing, and design communities.

Select this Article		Design of Integrated Bioinfiltration-Detention Urban Retrofits with Continuous Simulation Methods William C. Lucas, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)101 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the elements involved in the design of a bioretention planter/trench infiltration-detention system as an urban retrofit project. The system was designed to intercept all of the runoff from a synthetic 5.08mm 24-hr rainfall event. Diverted flows were conveyed into bioretention planter for treatment. The bioretention systems were fingerprinted into areas comprising 0.8% of the contributory drainage areas, with an associated stone trench comprising another 3.4%. The system was modeled using SWMM 5.0.014 continuous simulation (CS) software. Under existing conditions, over 80% of annual runoff exceeded the 3.50 L–s⁻¹–ha⁻¹ (0.05 cfs–ac⁻¹) threshold for initiation of combined sewer overflows (CSOs). Nearly all runoff was intercepted by the planter/trench infiltration system, and even with a soil infiltration rate of only 2.54 mm–h⁻¹, nearly 46% was infiltrated, and less than 8% was discharged at rates that could initiate CSOs. The number of CSO events was reduced from 74 to 4, a reduction of 95%. The volume of flows exceeding the threshold decreased by over 91%.

Select this Article		Design Optimization of Hydrodynamic Separators James H. Lenhart, P.E., D.WRE, Joanna B. Ogintz, P.E., and Scott A. de Ridder ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)102 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Typically, the sizing of hydrodynamic separators (HDS) for stormwater treatment is based on two factors. The first factor is the ability to remove a designated fraction of a particle size distribution, usually with a d₅₀ of 100 μm or greater. The second factor designates the magnitude of flow that needs to be treated from a given site. The techniques for determining the magnitude of flow vary, but two basic methods dominate. The first is a fairly simplistic method that requires the HDS to be sized to remove a target percentage of a specified particle size at a defined flow rate. The flow rate can be determined using a specified rainfall intensity and storm return period with a hydrologic model output, such as the Santa Barbara Urban Hydrograph. The second method, sometimes called the average annual load method, is based on calculations which use the storm depth (or intensity) frequency distributions converted to flows through a unit, which are then used to predict the removal performance. The removal performance prediction is based on laboratory studies of specific gradations of silica sediment, which have been tested to create a performance graph. These graphs often show plots of removal performance to the point where zero removal is achieved. These flows at zero removal are sometimes termed the “peak treatment flow”. This paper provides a perspective on this methodology and an approach to how sizing methods can be changed to optimize the total load reduction of a system by throttling the flow to a rate that is less the “peak treatment flow”.

Select this Article		Developing a Water Budget for a Constructed Stormwater Wetland Kristen Mogavero, Gerrad Jones, and Bridget Wadzuk ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)103 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A thorough understanding of the hydrology of a constructed stormwater wetland (CSW) is essential to develop a water budget; that is a comprehensive view of all inputs and outputs in the system. Two of the principal functions of a CSW are to 1) reduce peak flows and 2) improve water quality. The latter is achieved through biological, chemical, and physical processes that are ultimately governed by the hydraulics and hydrology of the system. As these built systems populate the watershed management landscape, it is necessary to account for all flows that pass through the CSW to ensure that it is providing a benefit and does not have any deleterious effects on the watershed. One of the most significant and least understood aspects of a CSW is the groundwater‐surface water exchange. This exchange is difficult to quantify, but is deserving of consideration because of the potential impact this exchange has on groundwater and surface water quantity and quality in a CSW system. Therefore, the goals of this study are to 1) use hydraulic and hydrologic computer models to create a water budget of the CSW, with a focus on quantifying groundwater‐surface water fluxes, and 2) discuss the implications of how hydraulic and hydrologic processes affect the water quality within a CSW.

Select this Article		Effects of Media Depth on Bioretention Performance in the Upper Coastal Plain of North Carolina and Bioretention Construction Impacts Study R. A. Brown and W. F. Hunt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)104 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bioretention is a principal low impact development (LID) practice. This paper examines two critical questions associated with bioretention design and construction. First, fill media is perhaps the major cost in constructing bioretention cells, so shallower media depths would be preferred, were they to work as well as deeper media systems. Two sets of bioretention cells of varying media depths in the upper coastal plain of North Carolina have been monitored since April 2008. They treat an impervious asphalt parking lot watershed in Nashville, NC. The bioretention cells were constructed with media depths of 0.6 and 0.9 m. Performance is being measured with respect to hydrology and water quality. Data show the deeper media depths meet the LID hydrology goal of volume reduction more frequently (35% compared to 9% of 45 events monitored). The second question examines how bioretention cells are excavated. Two excavation techniques, the conventional “scoop” method which purposefully smears the underlying soil surface and the “rake” method which uses the teeth of an excavator's bucket to scarify the underlying soil surface, were tested. Field tests were conducted on three soil types (sand, loamy sand, and clay) and under a variety of antecedent soil moisture conditions. Saturated hydraulic conductivity, surface infiltration, and soil compaction were measured for each excavated condition. In all cases, the rake method of excavation yielded more permeable, less compacted soils than the scoop method. The difference of infiltration and hydraulic conductivity between the two excavation techniques was statistically significant (p<0.05) when tests were conducted in wet soil conditions. Also, the infiltration rate at the clay site was significantly lower (p<0.05), and the hydraulic conductivity at the sandy site was significantly lower (p<0.05), when the scoop methodology was used. Based on results of this experiment and because there is essentially no extra cost associated with the rake method of excavating bioretention cells, the rake method of excavation is recommended over the conventional scoop method. The use of the rake method is expected to increase long term exfiltration from bioretention cells.

Select this Article		Engineered Waste Materials as Amendments to Prevent Erosion and to Stabilize Contaminated Sites S. P. Kakuturu, M. Xiao, and L. N. Reddi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)105 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Erosion is an important consideration in remediation strategies of slopes at contaminated sites such as mine tailings. Pelletized waste materials offer the dual advantages of waste utilization and soil erosion prevention at such sites. These materials could be designed to reduce stormwater runoff by optimizing their infiltration capacities, to trap the eroded soil particles and pollutants before they get to the nearby lakes and streams, and store sufficient moisture for supporting vegetation. In this paper, we present the results of our study that focused on flow, erosion, and filtration through an erosion control blanket built with three different particle size ranges of pelletized waste materials. The finest gradation is used on the upper portion of the slope, and the medium and coarse gradations are used in the lower portions to act as graded filters for the upper portion. The density, gradation, and erodibility properties of the waste materials are used for calculating the flow, internal erosion, filtration, and moisture retention in the erosion control blanket. The model is intended to aid in the engineering design of erosion‐resistant blankets on slopes. It optimizes the physicochemical and hydraulic characteristics of the pelletized waste materials to fulfill diverse functions of an erosion blanket, viz., erosion resistance, runoff inhibition, moisture retention to support vegetation, and controlled infiltration.

Select this Article		Enhancing Rain Garden Design to Promote Nitrate Removal Emilie K. Stander, Michael Borst, Thomas P. O'Connor, and Amy A. Rowe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)106 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Rain gardens effectively remove some stressors from stormwater, but in most cases they show much smaller removal rates of nitrate, likely due to the media's high sand and low organic matter content that inhibit nitrate removal by denitrification. EPA's pilot‐scale research explores the use of shredded, unprinted newspaper as a carbon source to fuel denitrification. A bench‐scale experiment was conducted to test the drainage capability of media containing shredded newspaper layers. Stormwater was introduced at low and high rates to bins containing zero, one, and two layers of newspaper at varying depths. While there were differences in effluent flow rates between control and newspaper treatments, surface ponding occurred in all three treatments, suggesting that some other factor besides the newspaper had an effect on drainage properties. Grain size and clay mineralogy analyses indicated that migration of finer particles into the deeper soils could have inhibited drainage.

Select this Article		EPA Aging Water Infrastructure Research Program: State of the Technology for the Condition Assessment and Rehabilitation of Wastewater Collection Systems Daniel J. Murray, Jr., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)107 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In 2007, the U.S. Environmental Protection Agency's Office of Research and Development (ORD) initiated a new research program to address our nation's aging water infrastructure. Under this new program, ORD established the goal to conduct research and demonstrations, and develop technical guidance to transfer innovative technologies and approaches for: (1) More cost‐effective operation, maintenance, repair and replacement of aging and failing drinking water and wastewater systems and (2) Development and application of advanced designs and management approaches for drinking water and wastewater systems. In addition, in its research plan for this new program, ORD structured the program following an advanced asset management framework. Under this framework, the program would focus primarily on buried water infrastructure and investigate new and innovative technologies and approaches for condition assessment, rehabilitation and infusion of advanced concepts. This paper presents the issues and state of the technology for the condition assessment and rehabilitation of wastewater collection systems, as defined to support this new research program.

Select this Article		Evaluation and Optimization of Distributed Stormwater Controls in Spreadsheet Joong Gwang Lee, Ph.D, M. ASCE and Scott D. Struck, Ph.D., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)108 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Maximizing on‐site stormwater management is one of the key concepts of distributed stormwater controls, such as those used as a part of Low Impact Development (LID) and sustainable sites approaches. These approaches are usually expressed as (1) maximize on‐site depression storage and infiltration, (2) minimize runoff discharge by minimizing directly connected impervious area (DCIA), (3) maximize flow paths and time of concentration, and (4) maximize the potential for evaporation and/or evapotranspiration (ET). A few process models are available to evaluate these types of distributed stormwater control alternatives directly. The purpose of this paper is to describe how to evaluate and optimize distributed urban stormwater control options in a spreadsheet environment. One methodology to evaluate stormwater control alternatives is to compare total runoff volume from long‐term continuous simulation. Using a lumped simulation model, it can be difficult to adequately represent the physical characteristics of distributed onsite LID options. Another alternative evaluation and optimization method based on lot‐level detailed functional spatial information and explicit rainfall‐runoff estimation is presented in this paper.

Select this Article		Evaluation of Atriplx Shrubs Growth in Semi Arid Area Mehemed A. Razzaghi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)109 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The effect of rainwater harvesting systems on the growth of Atriplx shrubs in semi arid land in western part of Libya was evaluated using two of rainwater harvesting systems (Contour lines and Negarim). Plant height, crown length, crown circumference and maturity were evaluated as measures to the effectiveness of these rainwater harvesting systems. Three micro‐catchments area (10.2, 12.5, and 15.5 m²) for each system were used. The catchment area was calculated on the basis of the average annual rainfall, surface runoff coefficient, plant water requirement, and root zone area. The ratio of the cultivated area to the catchment area was found to be 1:15. The growth of Atriplx shrubs was evaluated for two consecutive years. Both contour lines and negarim rainwater harvesting systems gave better results compared with the growth of the control shrubs (shrubs that were planted outside the W.H. systems). The overall efficiency of the systems varied from system to system and from catchment area size to other size. The contour line system and the larger ratio of the catchment area to the cultivated area were found to be strongly related to the growth of the shrubs.

Select this Article		Evolutionary Optimization of Combined Sewer Overflow Control Andrea Zimmer, David Hill, Barbara Minsker, Avi Ostfeld, and Arthur Schmidt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)110 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Model predictive control (MPC) is coupled with a real‐coded Genetic Algorithm to predict a decision sequence that minimizes combined sewer overflow (CSO) volume for a 3‐hour rainfall event over a hypothetical sewer system. Rainfall is transformed to overland runoff through the cell model which depicts each sewershed (draining to an overflow dropshaft) by two linear reservoirs in series, and water entering the interceptor is routed downstream to establish water levels at the dropshaft connections. A pumping rate at the most downstream end of the interceptor plus one sluice gate position for each dropshaft connection will be altered to produce the best control strategy. Resulting management scenarios disperse overflows differently throughout the sewer, but may yield similar overflow volumes. This paper describes the simulation approach taken and displays the overflow distribution for favorable control sequences.

Select this Article		Examinations of Pervious Concrete and Porous Asphalt Pavements Performance for Stormwater Management in Northern Climates Kristopher M. Houle, Robert M. Roseen, Thomas P. Ballestero, Joshua F. Briggs, and James J. Houle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)111 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In northern climates, runoff from standard pavements has varying seasonal effects on the surrounding environment. Year‐round runoff carries transportation associated contaminants into surface waters. During the winter and spring, deicing practices for pavements result in high levels of chloride‐laden runoff that is both toxic to aquatic biota and degrades drinking water supplies. The use of pervious pavements for parking lots for new and redevelopment projects are one watershed‐based strategy that can both mitigate impacts for new development and reverse impacts in areas with redevelopment. This study presents the findings from 2 pervious pavements, a pervious concrete and a porous asphalt parking lot, studied at the University of New Hampshire Stormwater Center. Winter in particular places great demands on pavements however it was observed that due to the well‐drained nature of the reservoir base that freeze thaw was limited. Surface infiltration rates, frost penetration, degree of snow and ice cover, and surface friction were measured on a monthly basis to assess winter performance. Frost penetration was observed to reach depths of eighteen inches however, surface infiltration capacities remained in excess of 200‐in/hr. Analysis of snow and ice cover and pavement skid resistance demonstrated that up to 75% less salt was needed for porous asphalt to maintain equivalent or better surface conditions as the reference dense mix asphalt lot. The annual median snow and ice surface cover for the porous asphalt lot was not significantly different than the reference lot with salt applications four times greater (p = 0.749 @95% CI). The annual median weighted skid resistance for the porous asphalt lot was 12% greater than the reference lot with greater salt application (p = 0.061 @95%CI). Pervious concrete did not demonstrate substantial salt reduction capabilities during storm events; however, ‘black‐ice’ formation did not occur during freeze‐thaw conditions indicating possible annual reductions. Pavement color and shading were found to be major factors influencing the amount and duration of snow and ice cover on the pervious concrete lot.

Select this Article		Field Evaluation of Indicator Bacteria Removal by Stormwater BMPs in North Carolina J. M. Hathaway, W. F. Hunt, J. D. Wright, and S. J. Jadlocki ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)112 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the United States Environmental Protection Agency's National Water Quality Inventory in 2000, 13% of the river and stream miles that were surveyed were impaired by pathogen indicator bacteria (USEPA 2002). Stormwater runoff is a transport mechanism for indicator bacteria to receiving waters, resulting in an increased risk to public health through consumption of contaminated shellfish or ingestion by swimmers. Urban stormwater is commonly treated by stormwater Best Management Practices (BMPs), each of which provides some combination of natural treatment mechanisms and fosters certain environmental conditions. Although BMPs have been studied in detail for many pollutants, little peer‐reviewed literature is available which documents their ability to remove or inactivate indicator bacteria. The North Carolina State University Department of Biological and Agricultural Engineering evaluated 10 stormwater BMPs in Charlotte and Wilmington, NC, to evaluate their efficiency with respect to indicator bacteria removal. The study practices included two bioretention cells, four stormwater wetlands, two wet ponds, and two dry detention areas. Data collected from these studies indicates that positive removal of indicator bacteria is possible in many types of BMPs; however, removal can be highly variable from practice to practice. Further, stormwater BMPs may foster environments where indicator bacteria can persist, becoming sources of indicator bacteria. Finally, even if positive reductions in indicator bacteria are noted, research indicates that achieving effluent concentrations of indicator bacteria consistent with USEPA standards may be difficult with many types of BMPs.

Select this Article		Field Testing Guidelines for Certification of Manufactured Stormwater BMPs: Part II John Sansalone, Jeff Benty, Ernie Carrasco, John Gulliver, Jon Hathaway, Bill Hunt, Masoud Kayhanian, Uday Khambhammettu, Robert M. Roseen, Betty Rushton, and Tim Williams ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)113 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Guidance from information and field testing concepts examined by the ASCE/EWRI Subcommittee on Field Testing is presented. Field‐testing of manufactured treatment devices requires critical planning and implementation through all steps of the verification process from watershed/catchment selection, to testing and analytical protocols, to data evaluation and quality assurance and control measures, to data reporting guidelines. Ultimately the goal of field testing is to provide verification of analytical or numerical models for BMPs that have been developed through scaled or full‐scale controlled physical model testing. The desired goals and outcomes must be known and designed into the entire verification process. Ultimately, the entire process leads to a defensible model that represents a quantitative yardstick for both deterministic and probabilistic evaluations of a BMP for stakeholders across a range of regional conditions. This committee is focused on field verification of a BMP for separation of particulate matter (PM) from rainfall‐runoff and snowmelt. Towards this goal, the entire gradation of PM requires characterization for a BMP field evaluation, in particular the suspended fraction because of the mobility and acute bio‐availability of this finer fraction. On the other hand, the coarse sediment fraction is of particular importance because this coarse fraction fills many BMPs and is most labile. A fundamental, transferable and defensible methodology is considered which includes particle size distributions (PSD) combined with gravimetric index tests for PM: total suspended solids (TSS) and suspended sediment concentration (SSC). TSS by definition is the PM fraction remaining suspended in an Imhoff Cone after one hour, although current methods utilize sub‐sampling generate controversy as to the meaning of the measurement. However TSS remains in use because of ubiquitous usage, regulatory significance and as an important index of treatability. In contrast, SSC provides a gravimetric analysis of the entire sample and therefore limited bias, and outstanding reliability and repeatability. Quality assurance and feedback protocol are a necessary part of the testing protocol. We must recognize the range of challenges and collect sufficient representative data within an event and across events so that the role of such uniqueness can be quantified for the specific BMP or BMPs tested.

Select this Article		From Grey to Green: Strategies and Concepts for Implementing Green CSO and Wet Weather Solutions James C. Schlaman, Bryce Lawrence, and Scott Schulte ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)114 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable wet weather and Combined Sewer Overflow (CSO) solutions that utilize green infrastructure and solutions are an increasing topic of interest. Identifying suitable locations for green infrastructure, developing appropriate concepts and quantifying their impact can be challenging. In the content of this paper, the authors will provide three strategies that address these challenges and present a comprehensive and holistic approach to incorporate green solution technologies into wet weather and CSO Long Term Control Plans.

Select this Article		Generalized Storage‐Reliability‐Yield Equations for Rainwater Harvesting Systems Lars S. Hanson, Richard M. Vogel, Paul Kirshen, and Peter Shanahan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)115 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Although rainwater harvesting (RWH) is gaining popularity as a sustainable water supply source in urban as well as rural areas, estimating required storage remains an important design challenge. This paper develops a robust, yet computationally simple equation for calculating required storage capacity for a RWH system, which is generally applicable in the United States (U.S.). A simulation model with a daily time step and a yield‐after‐spill algorithm is used to generate empirical Storage — Reliability — Yield (SRY) relationships for RWH systems at 232 U.S., first‐order precipitation gaging stations with long daily precipitation records. A regional regression modeling approach is used to combine system parameters (daily yield, collection area, reliability) with climatic variables (e.g. standard deviation of daily rainfall) to predict required storage capacity. Nationwide regression models for fixed reliability cases (80, 90, 95, 98%) demonstrate good fits (R²> 0.95) between model predictions and simulated storage capacities. The fits improve (R²>0.97) when the nation is broken down into smaller, more climatically homogeneous regions.

Select this Article		How the Heart of America is Goin' Green to Solve Water and Sewer Issues Lynn Hinkle and Michael Ports, P.E., PH, D. WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)116 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract As budgets tighten and the economy shows stresses from high energy costs, leaders are putting on their thinking caps and becoming creative problem solvers. In one aging American city that straddles a state line, Kansas City, such regional initiatives as 10,000 Rain Gardens, Conversations on the Environment, a regional Sustainability Academy, and the Kansas City Power and Light utility agreement with the Sierra Club to use more alternative energy sources such as wind power, have brought national attention and widespread acclaim. The appeal of goin' green as a region means that Kansas City can become a national model for sensible, sustainable growth. One way to be a national model is to learn from others about solving common urban issues like polluted stormwater runoff and raw sewage overflowing during wet weather due to antiquated combined sewers. Kansas City leaders have traveled to Seattle and Portland to view green solutions that treat water as a resource, capturing and using stormwater to recharge the water table. They have seen green infrastructure such as rain gardens, bio‐retention facilities, and stream buffers, which reduce storm water runoff and water pollution, create recreational amenities, and protect natural resources. These green solutions are integrated and include renewable energy, solid waste recycling, mass transit, bike/pedestrian infrastructure and other measures that reduce greenhouse gas emissions and improve environmental quality.

Select this Article		Graywater Irrigation as a Means to Meet Water Demands in Arid Regions Sybil Sharvelle, Masoud N Azar, Mary Stromberger, and Larry Roesner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)117 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Graywater irrigation systems offer many benefits, however the use of such systems has not become widespread due to concerns about safety issues. While some states have begun to legalize and regulate the practice of graywater reuse for residential landscape, little guidance based on scientific data has been provided for the safe operation of graywater irrigation systems. Limited scientific data is available on the fate of graywater chemical and microbiological constituents and the effect of these constituents on plant health after graywater is applied for irrigation. In this research we have examined the long‐term effects of graywater irrigation. We selected three households where graywater has been applied for irrigation for more than five years to include in this study located in California, Colorado, and Texas. Sampling locations were selected to encompass a variety of soil types and climatic conditions. Soil and plant samples have been collected in an area irrigated with graywater as well as a control area with analogous soil and landscaping that has been irrigated with potable water. Soil cores have been taken to a depth of 1 m and we have analyzed the presence of antimicrobials, and indicator organisms at depths of 0 – 13 cm, 13 – 30 cm, and 30 – 100 cm separately. Soil samples also were analyzed for indictor organisms including total coliforms, E. coli, Enterococci, Clostridium perfringens. In addition, infiltration tests were conducted in each sites to evaluate the effect of graywater on infiltration rate of soil.

Select this Article		HCFCD M3 System Maximizing and Maintaining Local Investments in Floodplain Modeling Karl McArthur, P.E., CFM, Stephen Bourne, P.E., Yu‐Chun Su, Ph.D., P.E., CFM, and Jacob Spenn, P.E., CFM ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)118 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Harris County, Texas, one of the most heavily populated and fastest growing areas in the nation, has 25% of its 1800 square miles located within the 1% annual chance floodplain. The District, in association with the Federal Emergency Management Agency (FEMA) recently completed a county‐wide Flood Insurance Study for Harris County, Texas (Houston, Texas) also known as the Tropical Storm Allison Recovery Project (TSARP), which encompassed the restudy of 22 major watersheds and approximately 1300 miles of channels. The hydrologic and hydraulic (H&H) models produced as part of this study became effective in June 2007 and the citizens, developers and engineers within Harris County are now actively using them. It is HCFCD's desire to protect their significant investment in these models by ensuring their efficient management and update into the future. As a result, the number of requests for the effective Flood Insurance Study models and the resultant frequency of updates to these models have prompted Harris County Flood Control District (HCFCD) to implement an automated system for model management.

Select this Article		Hydrologic Footprint Residence: A New Metric to Assess Hydrological Alterations Due to Urbanization M. H. Giacomoni and E. M. Zechman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)119 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Urbanization modifies hydrological processes in a watershed as surface alterations, such as the use of impervious cover, increase runoff volumes and modify the temporal patterns of the hydrograph. Higher peak flows and increased flood duration often lead to erosion and degradation of ecosystems. Typically, the peak flow for a design storm is used to assess the impact of land use change on the hydrological cycle. This approach, however, does not capture the extent of hydrologic change and impact on downstream communities. Floodplains have an important function in controlling downstream floods and sustaining sensitive ecosystems. This research proposes a new metric to quantify the effects of development based on the change in floodplain areas. The Hydrologic Footprint Residence (HFR) is proposed to evaluate the modification of floodplain areas and duration of a flood's residence. HFR can be used to analyze hydrological changes, gauge riparian ecosystem health, and develop watershed management plans. The use of HFR is demonstrated for a case study located on the Texas A&M University campus to evaluate the hydrologic impact of watershed development.

Select this Article		Hypothesis‐Based Flow Monitoring for Green Solutions Deb O'Bannon, F. ASCE and Erich Schmitz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)120 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A demonstration project to show the efficacy of stormwater best‐management practices deployed in an urban midwestern neighborhood. The large‐scale demonstration depends on reliable flow monitoring to verify stormwater invention by the green solutions and reduction of flows to the combined sewer collection system. The flow monitoring includes both temporal and spatial controls.

Select this Article		Impact of Wet‐Weather Peak Flow Blending on Disinfection Performance Mary K. Stinson, Richard Field, and R. Boris Rukovets ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)121 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A U.S. EPA study evaluated the impact on disinfection during peak flows (wet‐weather flow events) when a portion of the flow to the wastewater treatment plant (WWTP) bypasses secondary treatment prior to disinfection. The practice of bypassing secondary treatment during peak flows, referred to as “blending,” takes place when the volume of primary treatment flow exceeds the capacity of the secondary treatment. The bypassed flow is only treated by primary clarification before it is recombined with the fully treated secondary effluent prior to disinfection. Blending practice prevents passing of excess flow to secondary treatment, which could result in inactivation and destruction of the vulnerable biological process. The trade‐off is that during blending only a portion of the total flow receives full secondary treatment. The study was conducted at three WWTPs in New York City, ranging from 60 MGD to 275 MGD capacity. A total of four dry‐weather and 12 wet‐weather events were sampled and analyzed. Three samples from four sampling points of the treatment train in the WWTP were collected per event. The principal analytical parameters were fecal coliform, Enterococcus, viruses, and protozoa. Other parameters included total residual chlorine, BOD₅, and TSS.

Select this Article		Improving Hydrologic Sustainability of Texas A&M University Campus Prakash Khedun, Chandana Damodaram, Marcio Giacomoni, Andrea Ryan, Hillary Holmes, Ross Klein, William Saour, Michelle Hollingsworth, Troy Berthold, Meg Davis, Philip Bullock, Neetha Ravikumar, Emily Zechman, Georgianne Moore, Bryan Boulanger, et al. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)122 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This research investigates the hydrologic sustainability of urban development and stormwater management for a watershed on the Texas A&M campus. The main Texas A&M campus has become increasingly urbanized, resulting in areas of imperviousness that generate higher rates of runoff. This growth has proceeded unchecked, and significant growth and development are planned for the future. Both increased rates of runoff from previous development and the impact of anticipated development should be addressed through mitigation efforts. This research provides a means to assess watershed health through biological indicators, water quality indicators, riparian ecosystems, the floodplain footprint, and the long term flow regime. A modeling framework is implemented to couple hydrologic and hydraulics models to simulate a set of watershed management plans that employ alternative best management practices. Development plans will be evaluated based on a set of comprehensive metrics that synthesize ecological, hydrologic, and environmental aspects of watershed health. The selection of management plans based on these metrics will enhance the environmental sustainability of further campus development.

Select this Article		An Investigation of Infiltration in a Constructed Stormwater Wetland and Implications for Groundwater Quality Gerrad Jones, Kristen Mogavero, and Bridget M. Wadzuk ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)123 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Traditionally, detention basins and constructed stormwater wetlands (CSW) have been used primarily for peak flow reduction and water quality improvement and are assumed to possess negligible infiltrative capabilities. However, the potential for storm water infiltration within these structures and the associated non‐point source pollution of groundwater can not be ignored based on untested assumptions. The purpose of this research was to assess the infiltration capacity of a mature CSW on Villanova University's campus, in Villanova, Pennsylvania. Piezometers located within the CSW were monitored to develop a water budget and a chloride mass balance. The vertical gradients in the piezometers alternated between recharge and discharge patterns, with downward recharge gradients for baseflow conditions and upward discharge gradients after rainfall events. Preliminary water budget and chloride mass balance analyses suggest considerable reductions in volume and chloride load over a 6.5 day baseflow period in December, 2008. Although these findings suggest infiltration contributes to the water budget, it is unclear whether other explanations (e.g. perched water table or chloride stratification) could account for these patterns. Infiltration may be the most parsimonious explanation, but further research needs to be conducted to determine whether the negligible infiltration assumption is valid.

Select this Article		Integration of Low Impact Development Studies into the International Stormwater BMP Database Jane Clary, Marcus Quigley, P.E., Andrew Earles, P.E., Ph.D., Marc Leisenring, P.E., Eric Strecker, P.E., and Jonathan Jones, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)124 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Low Impact Development (LID) strategies are being encouraged in many communities as an approach to reduce potential adverse impacts of development on receiving streams. Many questions exist regarding how well various LID strategies perform in different settings, just as similar questions have been raised regarding performance of traditional stormwater best management practices (BMPs). Over a decade ago, Urban Water Resources Research Council (UWRRC) members worked to develop a set of standardized monitoring and reporting protocols for traditional BMPs and establish a master database for the purpose of evaluating BMP performance and the factors affecting performance. This effort culminated in the International Stormwater BMP Database (www.bmpdatabase.org), which contains data for over 350 BMPs and continues to operate as a clearinghouse for stormwater BMP data and performance analyses. During 2008–2009, the Stormwater BMP Database project expanded to better integrate LID into the database. This paper provides a condensed overview and progress report on the LID‐focused effort, including the following topics: 1) monitoring guidance for LID at the overall site development level; 2) an overview of recent changes to the stormwater BMP database to better accommodate LID studies, 3) a summary of LID studies currently included in the database; and 4) initial concepts related to evaluating performance of LID studies.

Select this Article		Kansas City — Balancing Green Infrastructure with Traditional Approaches for CSO Control Scott D. Struck, Ph.D., Tom Jacobs, Ginny Moore, J.D., Robert Pitt, Ph.D., P.E., D.WRE, Michael A. Ports, P.E., D.WRE, Deborah O'Bannon, Ph.D. P.E., Erich Schmitz, P.E., and Richard Field, P.E., D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)125 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Kansas City Missouri is perfectly positioned for demonstrating the use and effectiveness of applying green infrastructure for combined sewer overflow (CSO) control. The Kansas City Water Services Department (WSD) provides wastewater collection and treatment for approximately 650,000 people, located within the City and in 27 tributary or “satellite” communities. Approximately 56 square miles within Kansas City, south of the Missouri River, are served by combined sewers. The City's combined sewers overflow to a number of receiving streams, including the Kansas River, the Missouri River, the Blue River and Brush Creek. Kansas City has also suffered from severe flooding issues. Lives have been lost and significant property damage has occurred as a result of flooding, in large part due to substantial increases in stormwater runoff from ever‐increasing impervious surfaces. Kansas City's WSD has conducted extensive modeling and economic studies of its combined sewer system over the last 5 years, in preparation for submittal of its long term control plan to EPA, in January 2009. These studies and recent funding opportunities have provided the impetus for selection of Kansas City as a case study location to demonstrate the efficacy and sustainability of green infrastructure approaches in an urban‐core neighborhood served by a combined sewer system. The intent of this project is to compile data and demonstrate the water quality and quantity results from larger scale application of LID or micro‐BMP retrofits in a subcatchment.

Select this Article		Kansas City, Missouri Overflow Control Plan Summary Terry Leeds and Scott Struck ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)126 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Kansas City began building the basic sewer infrastructure that would allow the City to grow and prosper over 150 years ago. Amazingly, some of that infrastructure is still in use today. While focused on controlling overflows, a significant portion of the Overflow Control Plan addresses repairing, improving, and maintaining the City's basic sanitary sewer system so that it can be used by Kansas Citians for years to come. Kansas City's overall sanitary sewer system is comprised of both combined and separate sewer systems. A combined sewer system is simply a single sewer system that carries both sewage and stormwater. Kansas City has 58 square miles of combined sewers. Typically these systems are in the oldest areas of the City and are not capable of carrying the large amounts of stormwater that now run off of our urban landscape. During moderate to heavy rainfall events, the system will reach capacity, overflow, and discharge a mixture of sewage and stormwater directly to our streams and rivers. Although there is a desire to minimize these overflows, the discharge of combined sewer overflows is not uncommon from combined sewer systems and is allowed under a National Pollutant Discharge Elimination System (NPDES) permit issued to Kansas City's Water Services Department by the Missouri Department of Natural Resources.

Select this Article		Kansas City's Stream Setback Ordinance: A Case Study on the Benefits of Stream Buffers in Urban Areas Laurie Brown, Scott Schulte, and Bryce Lawrence ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)127 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Riparian buffers provide direct public and environmental benefits by stabilizing streams, separating people and structures from flood hazards, protecting public infrastructure from damage, and improving water quality. They also provide indirect benefits such as habitat preservation, recreational opportunities, public amenities and increased property values. Over the past 5 years the City of Kansas City, Missouri (City) systematically evaluated stream quality throughout the city and quantified the relationship between riparian buffers and stream quality. A comprehensive stream asset inventory demonstrated that the health and stability of the City's streams is influenced by the quantity and quality of riparian buffers. The results are bolstered by other studies from the Kansas City region, and support national research on the importance of stream buffers as a watershed management tool. for this reason, the City adopted a stream setback ordinance in August 2008 that prohibits floodplain development, while focusing on preserving adjacent riparian buffers through development controls, low‐impact development provisions, and incentives. This groundbreaking stream setback ordinance uniquely addresses stormwater management, natural resource protection, and future development by protecting sufficient riparian buffer to maintain the City's streams and environmental quality, while providing development incentives and flexibility to developers affected by the buffer. Flexibility, through the provision of “conservation development” options protects significant riparian resources while at the same time allowing development within the outer zone of the buffer.

Select this Article		KC‐One: Comprehensive City‐Wide Management Plan Creates Leading Stormwater Management Program J. W. Henson and R. Gaskin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)128 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Major floods have caused millions of dollars of damages, taken lives, and degraded Kansas City's streams. The City's Stormwater Management Program identified needed improvements over the last decade for the 320 square miles within the corporate boundaries. Approximately 1,000 projects were identified with estimated costs of about $1.8 billion to upgrade the drainage system and protect the residents, homes, and businesses in Kansas City.

Select this Article		Laboratory Testing Guidelines for Certification of Manufactured Stormwater BMPs Roger Bannerman, Hans de Bruijn, Shohreh Karimipour, Masoud Kayhanian, Jim Mailloux, Jon McDonald, Mark Miller, Omid Mohseni, Kwabena Osei, and Scott Perry ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)129 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract For the past decade, manufactured stormwater best management practices (BMPs) have been widely used in urban areas to remove suspended solids from stormwater runoff to meet the local and federal government agencies' standards. The ASCE/EWRI Task Committee on Guidelines for Certification of Manufactured Stormwater BMPs formed a subcommittee to develop the laboratory testing guidelines. The focus of this subcommittee has been on developing laboratory testing guidelines to assess the efficiency of the devices used for physical separation of the full spectrum of stormwater‐borne non‐dissolved solids. In general, these devices include hydrodynamic separators and filters. After reviewing the protocols developed by organizations, but not limited to, the state of Washington Technology Assessment Protocol‐Ecology (TAPE), the state of Wisconsin Method for Predicting the Efficiency of Proprietary Storm Water Sedimentation Devices, the TARP Protocol for Stormwater Best Management Practice Demonstrations, the subcommittee utilized the experience obtained from the laboratory tests conducted on these devices and employed the material in the existing protocols to develop the testing guidelines. These guidelines are designed to conduct robust laboratory testing with stated repeatability. The guidelines encompass three separate series of tests for addressing three different processes: (1) Testing to determine the efficiency of hydrodynamic separators in removing suspended sediments, (2) testing to quantify sediment retention of hydrodynamic separators, and (3) testing to determine the efficiency of filters in removing suspended solids.

Select this Article		Land Use and Runoff Uncertainty Celina Bochis and Robert E. Pitt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)130 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Data from about 160 neighborhoods in six Jefferson County, AL drainage areas were intensively investigated to determine the surface covers for each land use type. The data shows that the watersheds are highly impervious, with three of them having more than 50% of the watershed area composed of impervious cover. However, TR‐55 (USDA 1986) guidance still shows that the impervious cover for all land uses investigated to be much greater than we observed for our area. It was also concluded that the variabilities of the surface covers within the different land uses for the investigated areas was small, especially for the impervious covers. The percentage of directly connected impervious cover (DCIA) was determined by direct field observations and this data was also compared to commonly use empirical equations. Equations for determining DCIA developed during prior studies were fitted with our observed DCIA for our data, but they did not result in good relationships, especially when analyzed at the land use level. There was a good comparison between Sutherland's “highly connected basins” equation and the fitted equation for our overall data. However, the residual analysis for the regression model was poor, suggesting that the power equation may not be applicable to our data in our region. Suitable equations were developed for each land use separately, showing that a single equation could not be accurately used to estimate DCIA for all regions and land uses.

Select this Article		Linking Environmental Assessment and Solutions L. Gosselink, C. Herrington, and R. H. Glick ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)131 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Austin is proposing a revised water quality problem score calculation for its master‐planning process, which is used to direct allocation of resources for capital projects, programs and regulations. This change is proposed to address the challenge that Resource Managers face in identifying ecological assessment methods appropriate to their resource setting and particular information needs. Ecological assessment tools such as the City's Environmental Integrity Index (EII) include such a comprehensive suite of parameters that teasing apart the data to identify solutions and quantify potential benefits is difficult and not well documented. The revised problem score methods are more transparent and targeted to specific solution opportunities.

Select this Article		Long‐Term Effectiveness of a Bioretention System Treating Road Runoff in Northeastern Kansas Edward Peltier, Xiaolu Chen, Kelly Kindscher, and C. Bryan Young ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)132 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Recent studies have indicated that the use of ecologically‐based methods for stormwater treatment, including bioretention systems, may provide increased pollutant removal and protection of downstream receiving waters. However, there is little data addressing the long‐term performance of these systems in the field or the effects of contaminant accumulation over time on treatment effectiveness. In this study, we present results from an ongoing three‐year study of bioretention performance and contaminant fate at a 0.1 acre bioretention cell located in northeastern Kansas. Samples of influent and treated stormwater from storm events during 2007 and 2008 were analyzed for a range of water quality parameters, including total suspended solids, nutrients and total and dissolved Cu and Zn. Results of this sampling show that the bioretention system successfully removes > 70% of suspended solids and more than half of influent total metals. Removal of dissolved constituents is much lower, with the exception of nitrate, which had removal rates of up to 50% during the study. Improvements to the mulch material and vegetative establishment could potentially increase system performance for these constituents.

Select this Article		Looking Upstream and into the Watershed for the Big Picture of Stream Health Christina Y. S. Siu, Shirley E. Clark, Ph.D., P.E., D.WRE, M. ASCE, Ruth A. Sitler, and Katherine H. Baker, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)133 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When examining impaired river reaches, the primary focus is improving streamwater quality in the reach and downstream. The degree of damage to the river channel, the biological functions, and the river chemistry are assessed and restoration plans implemented. Few examine the causes of the degradation from upstream and upland areas and manage those problems before performing restoration work downstream. Without watershed management in the upper river system that addresses the stream's stressors, any restoration downstream becomes useless either relatively immediately or over time. Continued and potentially increased high peak flows from development during storms can wash out many restoration elements. Here, we examine the water management in the upper watershed of an unnamed tributary that passes through the Penn State Harrisburg campus, empties into the Susquehanna River, and eventually into the Chesapeake Bay. We also demonstrate the linkages between the lack of integrated water management and the current status of this tributary. The biota within the stream and surrounding the stream lack both diversity and richness. The streambanks are highly eroded and unstable. Current practices on campus (irrigation, grass cutting, etc.), as well as in the agricultural, residential, and industrial areas upstream, and any future campus development can hinder improving the stream's health. As restoration is being planned and implemented, the fact that this is an educational institution allows us to assess the stream's physical, chemical, and biological health both during dry‐weather and wet‐weather flows, as well as before and after restoration. We plan to evaluate whether on‐land restoration and improved stormwater management will affect the effectiveness of in‐stream and stream buffer activities. We also plan to continue both biologic and chemical health evaluations of the stream as a function of land‐use improvements. This project has supported several years of both undergraduate and Masters'‐level research.

Select this Article		LID‐SWM Practices as a Means of Resilience to Climate Change and Its Effects on Groundwater Recharge Iulia A. Barbu, Thomas P. Ballestero, and Robert M. Roseen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)134 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Many surface water bodies have been severely degraded by runoff from the centuries of continuous human development without regard to the impacts of stormwater. Local governments are beginning to responsibly respond to the need for action about increased imperviousness by adopting local Low Impact Development (LID) ordinances. The purpose of this study was to evaluate the hydrologic abilities of LID development to: reduce peak runoff flow rates to the pre‐development values; to infiltrate the recharge volumes mandated by current criteria; and to attenuate the impacts of extreme storm events. A numerical simulation was performed on a 4‐hectare site for pre‐development as well as residential development with Conventional and LID stormwater management design scenarios. Research results from four years of intense monitoring of LID systems at the University of New Hampshire Stormwater Center were integrated into these hydrologic models. Analyses were performed for hydrologic soil types A and C, for storms with recurrence intervals of 0.17‐, 2‐, 10‐, and 100‐years, as well as 2‐, 10‐, and 100‐years adjusted for climate change. The results show that the LID site design: generated much lower runoff volumes than the Conventional and Pre‐development site conditions; infiltrated more than the recharge volumes required by current regulations; and attenuated the impacts of extreme storms modified for climate change.

Select this Article		Maintenance of Stormwater BMPs Andrew J. Erickson, Joo‐Hyon Kang, Peter T. Weiss, C. Bruce Wilson, and John S. Gulliver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)135 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Many stormwater management manuals and guidance documents have stated the importance and estimated the necessary frequency of maintenance for stormwater best management practices (stormwater BMPs), but few have been able to document the actual frequency and intensity of maintenance required to maintain a desired level of performance and efficiency. Increased attention to mass balance, numerical goals, total maximum daily loads (TMDLs), and non‐degradation requirements has created the need for more emphasis on stormwater BMP operation and maintenance (O&M) in order to meet permitting and reporting requirements. The purpose of this paper is to advance knowledge about routine and non‐routine maintenance so as to develop more useful O&M plans. To do so, we reviewed literature throughout the United States for maintenance costs and developed, distributed, and analyzed the results of a detailed municipal public works survey. The specific goals of the survey were to identify and inventory O&M efforts and associated costs for stormwater BMPs. Survey questionnaires were sent to 106 cities, 28 of which responded. The survey related to the following topics: number of stormwater BMPs in the city, frequency of inspections and maintenance, average staff‐hours spent per routine inspection or maintenance, complexity of maintenance, most frequent causes of performance deterioration, and cost of non‐routine maintenance activities. The results of the survey revealed that most (89%) cities perform routine maintenance once per year or less. The most common causes of performance deterioration and the greatest expense were sediment buildup and litter/debris for most stormwater BMPs. The nationwide literature review resulted in predictive equations for O&M cost of stormwater BMPs as a function of total construction cost. A general rule of thumb is provided for estimating the relative importance of O&M in life‐cycle costs.

Select this Article		Modeling Performances of Detention Basins with Uncertainty Analysis Daeryong Park and Larry A. Roesner, Ph.D., P.E., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)136 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Best Management Practices (BMPs) correspond to actions and practices used to reduce flow rate and the constituent concentration in urban runoff. The extended detention basin is the most widely used among various types of BMPs. This study addresses the design guidelines for extended detention basins by applying uncertainty analysis to predict the magnitude of the widely varying urban nonpoint source pollution concentration expected in the BMP influent and effluent. With uncertainty analysis considered, urban nonpoint source pollution can be predicted with greater accuracy and better detention basin design criteria can be established for the protection of receiving waters. This study uses and Total Suspended Solid (TSS) as the representative water quality parameter from extended detention basin. Hydrologic and BMP geometric data of watersheds correspond to the location of these detention basins. This study incorporates the k‐C∗ model with uncertainty analysis to represent observed data. The k‐C∗ equation was chosen for the detention basins performance model because this model has been widely used for representing wetland treatment performances, but also can consider the performance effect for the physical dimensions of the BMP. This study will be able to support stormwater management decision makers in building detention basins of appropriate sizes with a better idea of the expected performance and risk.

Select this Article		Monitoring the Hydrologic Effects of an Extensive Green Roof Nathaniel Hanna Holloway, Charles J. Werth, and Arthur R. Schmidt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)137 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A well known consequence of urbanization is an increase in impervious area (parking lots, streets, roofs, etc), which carries along with it a number of undesirable side effects; such as an increase in storm water runoff and often a degradation of downstream water quality. Storm water best management practices (BMP's) are currently being implemented in many communities across the United States to address these consequences. BMP's increase the pervious area in an urban environment and thus imitate natural storm water processes (i.e. infiltration, filtration, evaporation, etc). BMP's have been shown to reduce runoff quantity whilst improving runoff quality. One specific BMP, green roofs, are proposed to reduce storm water runoff through storage and improve water quality through filtration. While there are data that support these assertions, they are largely insufficient to describe the processes that produce the runoff and water quality changes. As a result, prediction of the hydrologic effects of green roofs (and other BMP's) over a range of conditions often relies on assumed adjustments to empirical parameters such as percent impervious or runoff curve number. In order to provide process‐scale data describing hydrologic effects of green roofs, a monitoring system has been installed on an extensive green roof and an adjacent conventional roof on the new Business Instructional Facility on the University of Illinois Urbana‐Champaign campus. The green roof being monitored is approximately 280 square meters with 0.20 meters of soil and a variety of sedums planted. The conventional roof is approximately 45 square meters. The green roof station is monitoring: volumetric water content at 15 locations, soil temperature at 9 locations, air temperature and relative humidity at two heights, rainfall, runoff, incoming and reflected solar radiation, and temperature underneath the roof at 5 locations. The conventional roof station is monitoring: roof surface temperature at two locations, air temperature and relative humidity at two heights, rainfall, horizontal wind velocity, runoff, incoming and reflected solar radiation, and temperature underneath the roof at 2 locations. In addition, automated samplers collect water quality samples from the runoff of both the green and conventional roofs and a passive atmospheric sampler monitors deposition of particles. To date atmospheric condition data and soil moisture and temperature data have been collected for 20 storm events.

Select this Article		Multiple Watershed Scales Approach for Placement of Best Management Practices in SUSTAIN Fu‐hsiung Lai, Jenny Zhen, John Riverson, Khalid Alvi, and Leslie Shoemaker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)138 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Since 2003, the U.S. Environmental Protection Agency has been developing a decision support system for placement of best management practices (BMPs) at strategic locations in urban watersheds. This system is called the System for Urban Stormwater Treatment and Analysis INtegration (SUSTAIN). One dominant technical requirement for SUSTAIN is the ability to place management practices at multiple scales. To manage the complexity of larger watershed scale applications, SUSTAIN uses a tiered approach to evaluate both individual and multiple nested watersheds. In addition, for distributed BMPs in residential parcels of a new development or an existing neighborhood, SUSTAIN uses an optional lumped approach to aggregate BMPs by two generic BMPs, representing infiltration and storage processes. This paper describes the procedures for performing a tiered evaluation of BMPs at various spatial scales and aggregation of distributed BMPs. It illustrates framework features and performances through selected examples that are typical of the conditions and scenarios of watershed stormwater management. The tiered optimization implemented in SUSTAIN provides an efficient and manageable means for large watershed scale decision makings and allows users the flexibility in placing assessment points throughout a watershed where flow and pollutant load reduction goals are to be met.

Select this Article		Nexus Projects in Kansas City's Suburban Watersheds Brian Rast, P.E., CFM, PMP ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)139 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Two studies in Kansas City will benefit from the U.S. Army Corps of Engineers' emphasis on multipurpose plans and focus on systems. The Upper Turkey Creek and the Brush Creek Basin are both watersheds facing complex circumstances with many stakeholders. The studies are nexus projects, or planning efforts, using the watershed perspective to address the array of interrelated water resource issues through solutions that involve Federal, state, and local programs and projects. These nexus projects are defined by several characteristics, especially the strong integration uniting local, state, and Federal initiatives and recommendations for future stormwater management goals in the watersheds, including water quantity and water quality. An important characterization of nexus projects is the establishment of helpful processes in the watersheds, ranging from communication techniques to a decision process for evaluating best management practices and stream corridor restoration measures. The studies are providing forward looking, collaborative planning efforts to assemble multipurpose alternatives to address flood risk management, environmental degradation, and even recreation. The paper shows how nexus projects in an urban setting can lead to watershed management plans that establish useful processes, integrate the cities in achieving the goals of a shared watershed vision, and get the right projects implemented by first building strong partnerships.

Select this Article		Non‐Point Source Nutrient Loading in an Urban Watershed Eric Gurr and Fidelia (Ola) Nnadi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)140 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The United States Environmental Protection Agency (EPA) passed the Federal Clean Water Act (CWA) in 1972 which set the framework for the water quality standards for the entire United States. As a result of the CWA many point sources were eliminated, but in the process it became apparent that non‐point source loads represented even more of a threat. To further study the physical and chemical characteristics of urban runoff the Nationwide Urban Runoff Program (NURP) was established in 1978. This lead to series of management options, named Best Management Practices (BMPs) which proposed various structural and non‐structural methods to reduce nutrient loads. The present study attempts to generate accurate and effective water quality and quantity data that future stormwater management decisions can be based upon. The main objective of this study is to determine the nutrient loadings into the tributaries of Lake Tohopekaliga, using automatic monitoring sites established throughout the City of Kissimmee, Florida. These monitoring sites were located to monitor subbasins within the watershed such that inflows from outside the city limits can be isolated and external pollutant loads quantified. Additional internal monitoring sites were established to determine the pollutant loads of sections within the city.

Select this Article		Pervious Pavement System Evaluation Amy A. Rowe, Michael Borst, Thomas P. O'Connor, and Emilie K. Stander ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)141 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Pervious pavement is a low impact development stormwater control. The Urban Watershed Management Branch of the U.S. Environmental Protection Agency in Edison, NJ, is evaluating concrete pavers as a popular implementation. The pollutant removal of a bench‐scale permeable interlocking concrete paver system was evaluated using urban stormwater runoff from a 9 3/4‐acre drainage area. Stormwater was delivered to the pavement system twice daily to accelerate aging of the system, while monitoring clogging and long‐term pollutant removal. The role of microbial communities within the pervious pavement system in pollutant removal is also being examined. It is important to evaluate stormwater quality after filtration through pervious pavement systems to see if the exfiltrate has improved sufficiently for release to surface or ground waters. The bench‐scale phase of this study examined materials and system hydraulics to optimize for the full‐scale experiment. The project evaluated system performance with the presence of a geotextile between gravel layers using both woven and nonwoven fabrics along with control systems with no geotextile.

Select this Article		Planning for Sustainable Growth and Water Resources in the Chesapeake Bay Watershed Thomas E. Dumm, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)142 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Over the past several decades, a multitude of strategies, policies, and programs have been formulated and implemented in an effort to protect the quality of a most precious resource — the Chesapeake Bay. In 2006, Maryland passed a new law known as House Bill (HB) 1141 which directly addresses the relationship between planned growth and water resources. The Water Resources Element of HB 1141 ensures that future county and municipal comprehensive plans reflect the opportunities and limitations of the local and regional water resources. Situated on a peninsula in the Chesapeake Bay, Kent County, Maryland is nationally recognized for its rural character and serene beauty. Less than a two hour drive from Philadelphia, Baltimore and Washington DC, growth and development pressures have the potential to impact the sustainability of the water resources of the County. This paper includes a discussion of the following topics related to the update of the County's Water & Sewerage Plan which incorporates the Water Resources Element of HB 1141: (1) Overview of the Water Resources Element of HB 1441. (2) Tools and data sources (i.e., Source Water Assessments, TMDL's, land use plans, Chesapeake Bay Critical Areas, etc.). (3) Water resources limitations (i.e., infrastructure, susceptibility of potable water sources to pollutants, point source nutrient load caps, and TMDLs). (4) Methods for managing growth where there is limited resource availability (i.e., building permit limitations, down zoning, etc.).

Select this Article		Pollutant Transport within the Vadose Zone: Interactions of Soil Horizon Chemistry on Water Quality Daniel P. Treese, Shirley E. Clark, Ph.D., P.E., D. WRE, J. Bradley Mikula, and Katherine H. Baker, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)143 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Hydrologic cycle restoration is the primary objective of stormwater management. Infiltration and biofiltration systems composed of engineered soils have become a preferred tool for obtaining this objective while also providing pollutant removal. It is desirable, though, to limit soil disturbance and incorporate native soils. The use of native soils requires a fundamental understanding of their behavior towards water transport and pollutant treatment. Their structure is not homogeneous but instead contains several layers, or “horizons,” each with differing pollutant removal capacity. The ability of the various horizons to treat runoff was investigated over 40 simulated storm events in two soil types, a Wharton silt loam and Leetonia loamy sand. Effluent water results showed leaching of total nitrogen and removal of total phosphorus by all soil horizons of both soil types. Potassium leached from the organic horizons of both soils, the silt loam showed removal by lower horizons while the loamy sand did not. All soil horizons of both soil types lowered the pH of influent stormwater and increased conductivity, turbidity, color, and hardness.

Select this Article		Potential Data Analysis Methodology to Evaluate the Performance of Manufactured BMPs Masoud Kayhanian, Robert M. Roseen, James H. Lenhart, and Greg Williams ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)144 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Evaluating the performance of manufactured BMPs on a consistent and scientifically sound approach is beneficial for both the service provider and the services recipient. To do this properly, it is important that these devices need to be tested under a standard set of protocols. The testing data must be collected, reported, and validated prior data analysis. The testing, data collection, data reporting and validation will be addressed under a separate ASCE/EWRI subcommittee. The focus of this paper is to address the data analysis and performance evaluation of manufactured BMPs. To address this issue the existing statistical data analysis methods and performance evaluation that potentially could be used for manufactured BMPs have been examined in this paper. Special attention was devoted to the data distribution and the issue of normality since that will influence the selection of suitable data analysis approach. In general, it has been concluded that the stormwater data is log‐normally distributed. The existing BMP performance evaluation has also been evaluated and the effluent probability plot has been recommended to determine the performance evolution of manufactured BMPs.

Select this Article		Proposed scaling relations for manufactured stormwater BMPs John S. Gulliver, Qizhong Guo, John J. Sansalone, Gregory Williams, and J. S. Wu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)145 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Manufactured stormwater best management practices (BMPs) generally apply one or both of two unit operations to remove particles from stormwater runoff: hydrodynamic separation and filtration. Hydrodynamic separation is best used to remove sand particles, while filtration is used to remove organic particles as well as silt and clay. Many manufactured stormwater BMPs also have a chamber designed to remove floatables, or particles that are lighter than water. The numerous designs and multiple sizes of these manufactured stormwater BMPs suggest the need for scaling criteria to size and apply designs in the field. This paper reviews the scaling criteria research that has been completed, the research that may be adopted from other areas, and the needs for developing scaling criteria in manufactured stormwater BMPs.

Select this Article		Rainwater Harvesting for Non‐Potable Use in Gardens: A Comparison of Runoff Water Quality from Green vs. Traditional Roofs Natasha Nicholson, Shirley E. Clark, Ph.D., P.E., D. WRE, Brett V. Long, Julia Spicher, and Kelly A. Steele ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)146 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable stormwater management involves ensuring that site runoff not exceed the pre‐development peak flow rate and volume, typically accomplished through the use of water retention, infiltration, and reuse onsite through rainwater harvesting. Certain roofing materials, however, may be a pollutant source, thus, influencing the runoff's potential for harvesting. This project focuses on the first year of roof life for several traditional roofs and an extensive green roof. Substantial and significant releases of zinc and copper originated from an uncoated galvanized roof and from two treated woods, respectively. Roof runoff concentrations during early life indicated potential toxicity concerns for zinc and copper both in the water and from the potential buildup in the soil. Periodic elevated nutrient concentrations also were seen. Additionally, periodic spikes in pollutant concentrations after periods of low water concentrations indicated that elevated pollutant levels simply were not a result of washoff from excess preservative remaining on the surface of the material at installation.

Select this Article		Redesigning Constructed Stormwater Wetlands: An Integrated Modeling Approach to Optimize Form and Function G. D. Jones, K. A. Mogavero, and B. M. Wadzuk ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)147 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Constructed stormwater wetlands (CSWs) have tremendous potential in managing stormwater runoff. These systems are shallow marsh environments that are built to minimize both peak flow rates and contaminant loads to aquatic ecosystems following storm events. In order to meet these goals, CSWs are constructed with few guiding principals. Despite these principles, little research has been conducted to optimize the biological, chemical, and physical processes involved in stormwater mitigation. A four tiered modeling approach is underway to redesign Villanova's CSW, however, this paper focuses on MIKE 11 a hydraulic model. Four plan view designs were created which included a one pond, two pond, one pond and meander, and continuous meander design. Using the same inflow data, a modeled outflow hydrograph was simulated. Three parameters were obtained from this hydrograph: peak flow rate, time to discharge, and time rate of change of flow. The best performing design was the continuous meander design which had the lowest peak flow rate, longest stormwater discharge time, and lowest mean change in flow rate. The second best performing design was the one pond design. As a general rule of thumb, increasing the length to width ratio increases the hydraulic performance. Although this may be true, the single pond design had the lowest length to width ratio but was the second best performing model. Based on these results, volume storage was the best predictor of model performance.

Select this Article		Research of Hydrologic and Water Quality Performance of 4 Linear Wetlands in Eastern North Carolina J. D. Wright and W. F. Hunt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)148 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The North Carolina Department of Transportation is charged by an agreement with the North Carolina Department of Environment and Natural Resources to treat stormwater from NC DOT facilities across North Carolina. One heretofore unaccounted treatment is hundreds of miles of right‐of‐way swales in eastern North Carolina. It is possible that these serendipitous practices are improving runoff quality along theses highways. If so, an assessment of their performance is needed. Four existing right‐of‐way linear swales along I–40 east of I–95 will be monitored to determine their hydrologic and water quality effectiveness. Two different treatments are being examined: one swale that is unaltered and one that has been allowed to establish wetland conditions. There are two examples of each. Monitoring will also address the impact of the vegetated filter strip between the shoulder and the edge of the swale. Monitoring began in August of 2008. Samples are being collected from 18 events and analyzed for TN, TKN, NH₄–N, NO_2–3–N, TP, and TSS.

Select this Article		Reservoir Sedimentation Estimation Using Genetic Programming Technique Vaibhav Garg and V. Jothiprakash ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)149 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract To a certain extent, all reservoirs are subjected to the problem of sediment deposition universally. Depending on the amount of material deposited the shortening of reservoir capacity and useful life result in several unpredictable consequences. To determine the total quantity of deposition, as well as the pattern and distribution of deposits in a reservoir, hydrographic survey is the only direct measurement method. These hydrographic survey methods are being considered as expensive, time consuming and cumbersome. In the present study, an attempt has been made to employ genetic programming (GP) soft computing technique to estimate the volume of sediment retained (S_v) in the Pong Reservoir, India. It was found that GP model captured the trend and magnitude of S_v very well. Moreover, GP model provided input‐output relationship in the form of computer programs which may be easily used by end user. Also, GP can be effectively used to capture the non‐linear relationship between the input and output with short length of data.

Select this Article		Sediment Monitoring Bias by Autosampler in Comparison with Whole Volume Sampling for Parking Lot Runoff George D. Fowler, Robert M. Roseen, Thomas P. Ballestero, Qizhong Guo, and James Houle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)150 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A field study was conducted to assess biases of suspended sediment concentration (SSC) analyses (ASTM standard D 3977–97) performed on discrete samples obtained by auto‐sampler in comparison with actual sediment concentrations from whole volume sampling. Research results indicate that the biases attributed to monitoring of sediment event mean concentration (EMC) and particle size distribution (PSD) in parking lot runoff by automated samplers (non‐isokinetic) can be insignificant. Large volume samples (∼15,000 L) of the full pipe cross‐section were taken from a stormwater sewer system for eighteen storm events over two years to monitor for EMCs and PSDs. Concurrently, flow weighted grab samples were obtained by automatic samplers throughout the entire large volume sampling period. Thus characteristics of sediments were compared from a “whole storm” sample with that of “sub‐samples” obtained by an autosampler using non‐isokinetic sampling. SSCs and particle size distributions were compared for the two respective field sampling methods. The two methods showed a strong correlation for median sediment EMCs (R² = .9801, n = 18). Biases to particle size distributions were found to be largely confined to the large particles (>160 um) representing less than 25% of the load by mass. Moreover, sediment particles captured by the whole volume sampling and autosampler were not significantly different (α = 0.05) for D₅₀'s = 0.067 = and 0.047 microns respectively (particle size at which 50% of the sample mass is less).

Select this Article		Selecting Optimal Water Supply Options — A Regional Water Supply Case Study in the Upper Kissimmee Basin, FL Aditya Tyagi, Mitchell Griffin, Richard Nevulis, and Chris Sweazy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)151 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Central Florida's population is growing at a rapid pace and is approaching the limits of its available groundwater supplies. Considering this fact, the South Florida Water Management District (SFWMD), St. Johns River Water Management District (SJRWMD), and Southwest Florida Water Management District (SWFWMD) foresee that additional groundwater withdrawals in Central Florida to meet future water demands beyond 2013 will be restricted. The objective of this initial feasibility study is to evaluate the availability of surface water in the upper Kissimmee River basin as an alternative supply source for Central Florida. As part of the Upper Kissimmee Basin Regional Water Feasibility Study, 28 integrated water supply options were identified and evaluated by developing a reservoir optimization model that minimizes both capital and O&M costs of various water supply components, such as intakes, reservoirs, water treatment plants, pumps, pipelines, and groundwater withdrawals, and so forth, and satisfies necessary physical constraints. The optimization approach appropriately sized the various water supply system components from both surface and groundwater sources to meet a desired yield target while addressing the primary environmental performance measures identified for the Kissimmee River restoration effort. In addition to minimizing water supply cost, reliability was also maximized using a multi‐objective genetic algorithm. A key component of the feasibility study is to provide a planning‐level estimate of surface‐water availability and reservoir sizing for one or more project locations within the study area. This work was completed in August 2008 using interim operational criteria for the Upper Kissimmee Chain of Lakes. Additional refinements to the estimates of water availability and reservoir sizing are anticipated in the future as the current environmental criteria and operation schedules of the lake structures are modified in 2009.

Select this Article		Simplified Solution for Groundwater Mounding under round Stormwater Infiltration Facilities Kaveh Zomorodi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)152 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A study was conducted to derive new groundwater mounding equations that are simple in their structures but produce reasonable values for conditions most commonly found in stormwater infiltration facilities. This paper presents the new simplified equations and their theoretical development. The equations apply to Steady‐uniform recharge rate to infinite homogenous aquifers with initially horizontal water table and bedrock surfaces. Separate sets of equations were derived for recharge strips (infiltration channels/trenches) and infiltration basins (round or square facilities). The equations for recharge strips were published previously. This paper presents the equations for round or square facilities. The new equation sets require minimum input data in terms of the size and shape of the facility, the properties of the saturated layer and the recharge rate and are convenient for routine engineering calculations. Example applications of the new equation sets for conditions typical in New Jersey are presented.

Select this Article		South Lake Park Bioretention Gardens J. J. Dremsa and T. A. Hartsig ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)153 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The South Lake Park Bioretention Garden project consists of a survey, layout, design, and plans for parking lot reconstruction and bioretention grading and underdrain system. The layout and grading for both the parking lots and bioretention cells were challenging aspects for the following reasons: matching the existing grade for adjacent constraints, regulating the amount of water that each cell received, and taking special care to evenly distribute how the water flowed into the cells to minimize erosion and possible cell damage. Applied Ecological Services, Inc. (AES) was asked to design alternative BMPs as demonstration projects at two parks in Overland Park, KS. AES was selected because of its expertise in natural systems and ecological restoration. Understanding that failure of poorly designed BMPs has resulted in public doubts, AES anchored their design by conducting infiltration tests of engineered bioretention soils. The attention the team gave to the site layout, construction sequence, and native plant selection has lead to successful results.

Select this Article		State of the Practice of Wet Weather Flow Analysis Mitchell Heineman, P.E., M. ASCE, D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)154 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Engineers analyze wet weather flow in collection systems using a variety of computer tools and analytical techniques. Tools and data available for performing these analyses have greatly advanced since software for this purpose was first standardized in the 1970s. The practicing engineer today has access to GIS‐based modeling software, high‐resolution land cover and elevation datasets, and enormous hydrologic databases. Methods used for typical engineering work have advanced quite modestly by comparison. Furthermore, there is little standardization of how analyses of drain, combined sewer, and sanitary sewer collection systems are carried out, despite considerable commonalities among their wet weather performance. This paper reviews the state of the practice of collection system modeling, considering software availability and selection, model complexity, calibration criteria, and simulation methods. Urban modeling protocols for drain, combined, and sanitary sewer systems are discussed. Uniform approaches for model calibration are suggested. Finally, the paper identifies research and development needs where the state of the practice is limited by current technology.

Select this Article		The Application of Environmental Site Design Processes to Design a Residential Subdivision Steven D. Trinkaus, P.E., CPESC, CPSWQ ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)155 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Strategies of Low Impact Development (LID) are best known as alternative treatment systems to reduce the impact of storm water runoff on the environment. A more important aspect of LID is the implementation of Environmental Site Design (ESD). ESD is a design process to evaluate the environmental conditions on a parcel of land prior to the creation of a land development project. This process is most important for residential developments. While ESD can work with any land use regulations, the most environmentally sound developments will occur in those communities, whose land use regulations that permit “cluster” or “open space” designs. This paper will explore the strategies and steps necessary to create a residential subdivision utilizing ESD.

Select this Article		Effect of Bioretention on Runoff Temperature in Trout Sensitive Regions Matthew Jones, Ph.D., E.I. and William F. Hunt, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)156 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Although it has been established that thermal pollution from urban stormwater can negatively impact the aquatic ecosystem, there are few mechanisms available to reduce the temperature or urban stormwater runoff. A monitoring study was conducted at 4 bioretention areas in western North Carolina, located along the southeastern extent of United States trout populations, to examine the effect these systems have on runoff temperature and identify any design criteria pertinent to temperature reduction. Median runoff temperatures leaving the pavement surfaces, based on storm events, exceeded the 21°C upper avoidance temperature of trout at all sites during the months of June through September. Of the bioretention areas studied, the two systems that covered an area smaller than 10% of their contributing watershed were able to significantly (p<0.01) reduce both maximum and median storm temperatures between the inlet and outlet. At the two bioretention areas that were larger than 10% of their contributing watershed area, maximum effluent temperatures were significantly (p<0.01) cooler than influent temperatures; however, there was no significant (p<0.05) difference between median influent and effluent temperatures. Despite reductions in temperature, effluent temperatures were not significantly (p<0.05) cooler than the upper avoidance temperature for trout at any of the monitoring locations. There was evidence that substantial reductions in runoff volume occurred at all bioretention areas, especially the systems that were larger than 10% of their contributing watershed. Overall, monitoring results indicated that bioretention areas served as effective treatment mechanisms for reducing, but not eliminating, the thermal impacts associated with urban stormwater runoff.

Select this Article		The Lawrence Technological University Greenroof Performance Evaluation Project Donald D. Carpenter, Ph.D. A. M. ASCE and Preethi Kaluvakolanu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)157 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Lawrence Technological University is a private university located on a 120‐acre campus in highly urbanized Southfield, Michigan (Detroit Metropolitan Area). The campus was primarily developed over the last several decades with limited or no stormwater controls as was customary with regulations of the time. However, the opening of a student services center in 2005 provided the opportunity for the campus to commit itself to green design and the use of low impact development (LID) techniques. The 40,000 square‐foot A. Alfred Taubman Student Services Center (Center) is a Leadership in Energy and Environmental Design (LEED) Silver Certified green building that features a 10,000 square foot green roof; geothermal heating and cooling; cistern water harvesting; a bioswale, and other energy efficient technologies. As such, the Center provides a living laboratory for Lawrence Tech architecture and engineering students, local municipal officials, community planners, and design engineers to learn about LID techniques and LEED certification. Of specific interest to stormwater management, the building features a 10,000 square foot Hydrotech Garden Roof™ and gray water cistern that recycles roof water. The presence of the green roof provided an unique opportunity to compare and contrast the hydrologic performance of a full‐scale greenroof with other more traditional roofs on campus. This was accomplished by outfitting three separate roof drains (a traditional blacktop asphalt roof, a rock ballasted roof, and the green roof) with water quality and quantity sensors. Objectives of the Greenroof Performance Evaluation Project include the overall volume of precipitation retained and detained by the green roof compared to the other roofs on campus; the peak discharge and run‐off coefficient reduction of the greenroof for various storm events, the nutrient loading attenuation capabilities of the greenroof; the reduction in ambient temperature associated with the greenroof; and the educational benefit of establishing a long‐term monitoring station capable of determining the temporal performance of the green roof that could be integrated into the curriculum.

Select this Article		The Road to LID Plan Approval in Coastal North Carolina: Development of a Spreadsheet Modeling Tool for LID Based Designs Hunter Freeman, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)158 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract North Carolina has an abundance of natural resources and a climate that has helped make it one of the fastest growing states in the nation. With the growth and the jobs, comes the challenge of protecting the environment and quality of life that makes it such a desirable place to live. This is especially true for the 20 coastal counties, where stormwater policies are being updated to protect shellfish habitats and enhance water quality. In theory Low Impact Development (LID) practices are one means to achieve high water quality standards, but until recently guidance for implementing this type of program at any level has been scarce. To that end the North Carolina Coastal Federation (NCCF) with National Oceanic and Atmospheric Administration (NOAA) grant funding and contributions from three jurisdictions: the City of Wilmington, New Hanover County, and Brunswick County, spearheaded the development of LID specific stormwater design manuals and a spreadsheet based modeling tool for each local government. The model was developed to assist engineers and developers with the permitting and approval of LID stormwater management plans as well as act as a tool for the reviewing agencies to use in the approval process.

Select this Article		The Runoff Reduction Method Kelly A. Collins, Dave Hirschman, Greg Hoffmann, and Tom Schueler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)159 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In 2008, the Center for Watershed Protection and the Chesapeake Stormwater Network developed the Runoff Reduction Method. The method was developed as part of a project to research and update best management practice (BMP) performance and, in particular, ascertain the ability of various BMPs to reduce post‐development runoff volumes. The method focuses on the capability of conventional and innovative stormwater management practices (e.g., permeable pavement, green roofs, rainwater harvesting, bioretention, downspout disconnection, etc.) to reduce runoff, as well as remove pollutants, and incorporates built‐in incentives for environmental site design, such as forest and open space preservation. Because of the high runoff reduction capabilities of various site design and innovative stormwater practices, implementing these innovative practices at a site reduces the overall number and size of structural BMPs required. This approach helps put innovative stormwater management practices on a level playing field with conventional stormwater management practices, such as wet and dry ponds. Currently, various state programs are in the process of using or adopting the Runoff Reduction Method as part of regulatory and non‐regulatory programs. The Virginia Department of Conservation and Recreation (DCR) is integrating the Runoff Reduction Method into proposed stormwater management regulations and an updated stormwater management handbook. The Georgia Department of Natural Resources is modifying the method for a new Coastal Stormwater Management Manual Supplement. The State of Delaware is using the concept of runoff reduction in proposed statewide regulations. With the incorporation of the Runoff Reduction Method into these programs, communities are poised for the wide‐spread implementation of low impact development and innovative stormwater management practices on development sites.

Select this Article		Unit Process Modeling of Stormwater Flow and Pollutant Sorption in a Bioretention Cell Zhuangxiang He and Allen P. Davis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)160 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bioretention is a mulch/soil/plant‐based low impact development facility employed to collect, store, infiltrate and treat urban stormwater runoff. This work focuses on modeling to describe the fate of stormwater and the adsorption of pollutants in bioretention facilities. A two dimensional Variable Saturated Flow and Transport Model is developed based on partial differential equation modes in COMSOL Multiphysics, in which both fluid flow and solute transport are under transient analysis. Model results indicate that the outflow volume is less than the inflow due to the storage and the extent of initial unsaturation in the media. The outflow volume from loamy sand media (with larger K^s) is larger than that from sandy loam media. The flow peak is reduced. Concentrations of naphthalene (NP) and pyrene (PY) in runoff vary with depth and most NP and PY (> 90%) is removed within about 3 cm media depth.

Select this Article		Use of the Basin Development Factor to Evaluate Urban Watershed Response Shiva Sunder, Theodore G. Cleveland, and David B. Thompson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)161 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Basin Development Factor (BDF) is a reasonably straightforward categorical variable that has promise for estimating urban hydrologic response. The objective of this study is exploratory — the goal is to learn whether the BDF improves the explanation of the rainfall and runoff responses of watersheds. This particular metric is attractive as an alternative to other metrics in use. The BDF was determined for more than 100 watersheds in Texas and then used to generate estimates of unit hydrograph timing characteristics and peak discharge characteristics. Simulated responses using these values are compared to both observed and prior simulated responses for the same watersheds. Inclusion of BDF as an explanatory variable in the regression analyses in this study to generate hydrologic responses did not materially reduce, or enhance performance in models of selected watersheds. This finding indicates that use of BDF cannot make estimates worse, but does not improve estimates either (and thus BDF as implemented here could be ignored). The result was discouraging, but the particular effort overlooked that the regression models used could estimate zero discharges, when, in fact, the actual database did not contain zero values. Despite the discouraging result, the authors believe that the BDF bears further study and suggestions for such studies are offered.

Select this Article		Water Quality and Hydraulic Properties of the Permeable Friction Course Michael Barrett, Ph.D., P.E., D.WRE, Brandon Klenzendorf, M.S., Brad Eck, M.S., and Randall Charbeneau, Ph.D., P.E., D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)162 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this study is to document the water quality benefits and the hydraulic properties of PFC. Stormwater runoff from a four‐lane divided highway in Austin, Texas, USA was monitored at the edge of pavement at two sites before and after the installation of a PFC. Observed concentrations of total suspended solids and pollutants associated with particulate material were much lower in the runoff from the PFC than that derived from the conventional asphalt surface. Significant concentration reductions were observed for total suspended solids, total lead, total copper, and total zinc. The reduction in TSS concentration is about 90 percent and the average discharge concentration is less than 10 mg/L. Concentrations of dissolved constituents were not significantly different at either site. These results are generally consistent with findings of research conducted in Europe. Results of this study indicate that PFC performs as well as many types of structural controls for reducing the pollutants in highway runoff. Consequently, this material that has historically been used primarily for safety benefits should also be considered where reduction in pollutant discharge is desired. This material incorporates runoff treatment within the pavement itself, which facilitates its use in retrofit situations where additional right‐of‐way may not be available for stormwater treatment.

Select this Article		Water Quality Design Storms for Stormwater Hydrodynamic Separators Victoria J. Fernandez‐Martinez and Qizhong Guo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)163 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When measure of the device performance is based on laboratory data, NJCAT calculates the average annual removal efficiency using the NJDEP‐specified weighting factors. In this study, ten years of precipitation records were used to quantify frequency distributions of runoff volumes/depths as well as runoff peak flow rates. The SWMM model was used to simulate the runoff events produced by the given precipitation events. The model results indicate that the weighting factors, based on frequency distribution of the peak runoff rates normalized by the peak runoff rate generated by the uniform‐intensity water quality design storm, are close to the NJDEP‐specified weighting factors. The impact of using two different water quality design storms, uniform vs. non‐uniform intensity distribution, to size an interim‐certified hydrodynamic separator was also evaluated. The SWMM model was used to continuously simulate solids loading to the treatment device. The lab‐measured relationship between flow rate and removal efficiency was used to specify the removal rate of solids within the storm event. The model results also indicate that sizing with the uniform‐intensity design storm would achieve a removal efficiency close to the one verified. Sizing with the non‐uniform intensity design storm, although could be taken as a conservative approach, would achieve the removal efficiency considerably higher than the one verified.

Select this Article		Water Sustainability Index: Application of CWSI for Ahwaz County J. Attari and S.A. Mojahedi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)164 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sustainability of water resources is vital especially for developing countries such as Iran which are located in the Middle East and North Africa (MENA) region where water is scarce. To balance the high demand of water for economical growth and at the same time preserve the environment for present and future generations, sustainability of water resources should be considered by monitoring and data mining. For this purpose, several quantified indices have been proposed and applied world wide recently. In this paper, the Canadian Water Sustainability Index (CWSI) proposed by PRI, has been trailed for the case of Ahwaz County, a community located in South West of Iran fed by Karun River. Required data for the composite CWSI score which is the average of five major theme‐based components (i.e. resource, ecosystem health, infrastructure, human health capacity) was collected according to the PRI evaluation method. In addition to the standardized CWSI, the final index was also calculated considering weight estimation for the five components by pair‐wise comparison, using Expert Choice version 2000. Results showed that application of this index as a policy tool, with some modifications in weights, was satisfactory for the educational case study and could be replicated for other communities in Iran.

Select this Article		Development of Watershed Management Modeling System: The Los Angeles County Flood Control District's Watershed Based Approach for Urban Runoff and Stormwater Quality Youn Sim, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)165 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Improving the quality of urban runoff and stormwater in the Los Angeles County's coastal watersheds is challenging. Thousands of separately permitted discharges with multiple Total Maximum daily Loads flow into the same receiving water bodies simultaneously. This makes it necessary and economical to address many different pollutant sources concurrently. In order to help overcome such challenges, the Los Angeles County Flood Control District is developing a watershed modeling system (WMMS) that would ultimately identify cost‐effective projects through an integrated, watershed based approach. Using WMMS, collective impact of a variety of pollutant sources from point to non‐point is evaluated and thereby comprehensive, long‐term strategies for overall water quality improvement of the entire watershed will be planned. In addition, the WMMS will be used as an integrated watershed management tool for future planning of projects that achieve multiple benefits besides water quality such as water conservation, flood control, and open space development. This would eventually allow for an effective stormwater resource management.

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AQUIFER CHARACTERIZATION AND PROTECTION

Select this Article		Implementing Source Water Protection Programs in Texas Camille W. Sowells, P.E., BCEE, Christina Petersen, Ph.D., Gordon McCurry, P.G., Alexandria Doody, and Sean Ables, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)166 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The water that surrounds us — lakes, rivers, streams, and aquifers — makes up our drinking water sources. These source waters can be threatened by a number of potential sources of contamination, such as on‐site septic systems, sewer lines, hazardous chemical storage, storm water runoff, and animal wastes. The determination of the potential or risk is a key component of the source water assessment. The Texas Source Water Assessment and Protection (SWAP) Program was promulgated as part of amendments to the 1996 Safe Drinking Water Act and consists of two fundamental aspects: Assessment and Protection. Source water assessments determine a water supply's susceptibility to contamination. Source water protection is the implementation of management strategies or practices to mitigate or eliminate risks associated with potential sources of contamination (PSOC). The assessments and protection plan are specific to each public water system, its source waters, and areas of concern which may impact source waters. The objective of this paper is to discuss the innovative methodology used to encourage development of source water protection programs and conduct source water protection activities for selected public water systems using groundwater as the water supply. The methodology includes both technical activities as well as educational and outreach efforts to encourage active participation in the program. This paper will document the process used and present the results of these activities in multiple communities.

Select this Article		Lithostratigraphy of Nigeria—An Overview Kazeem Akorede Shitta ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)167 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Nigeria lies very close to the equator (hot country) West coast Africa between latitude 4 N and 14 N degree and longitude 2 E and 15 E degree. The country is located at the Northern end of Eastern branch of west coast of Africa rift system. Nigeria geological set up comprises broadly sedimentary formation and crystalline basement complex, which occur more or less in equal proportion all over the country. The sediment is mainly Upper Cretaceous to recent in age while the basement complex rocks are thought to be Precambrian. The studied area lies between latitude 12.4” and 11.11 ”W and longitude 13.81” and 14.13” S. The studied area is underlain by Precambrian basement complex of southern western Nigeria. The major rock in the area is charnokite and granite rock. The granite rock which are member of the older granite suite occupy about 65% of the total area. The principal granite is petrographic variety are recognized. The fine grained biotite‐granite medium‐coarse, non porphyritic biotite ‐hornblende granite and coarse‐porphyritic biotite‐hornblende granite. Also three main textural type of Charnokitic rock are also distinguished are coarse grained, massive fine grained and gneissic fine grained. The mode of occurrence of rock is three (1) core of the granite rock as exemplified by study area and few smaller bodies (2) Margin of the granite bodies as seen in Ijare and Uro edemo‐idemo Charnokitic bodies and (3) Discrete bodies of the gneissic fine grained Charnokitic rock within the country gneisses as seen in Ilaro and Iju and Emirin village. All the charnokite in the region are dark‐greenish to greenish‐gray rocks with bluish quartz and greenish feldspar.

Select this Article		Specific Problems Related to Partially Penetrating Wells in Confined Aquifers Ahmad Wagdy, Hany G. Radwan, and Sherif M. El‐Didy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)168 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Partial penetration, especially for confined aquifers, may significantly affect the associated well(s) hydraulics due to the incidence of vertical flow in the vicinity of the well. This induces additional head losses, affects the potential pumping rate, and the related peizometeric head distribution around the well. Closed form analytical solution is beyond manual computations due to complicated integrations and summations in addition to dealing with a large number of variables. The main objective of this paper is to provide engineers with a simplified, yet accurate, solution to three specific problems, of common occurrence. Defining the effective aquifer thickness, in case of partial penetration for confined aquifers, is one problem. In case of unknown aquifer thickness, the performed analysis recommends to define the effective thickness as a multiple of the screen length, which in turn, is time dependant. Multiple values of 2, 3, and 4 are found to correspond to pumping periods of 1, 3, and 10 days, regardless of the pumping rate. Determining the optimum screen length for maximum well yield is a second problem. A screen design chart has been prepared while taking into consideration empirically‐derived well capacity equation. Detecting the zone of influence of a partially penetrating pumping well is the last studied problem. The peizometric head at any radius can be estimated from proposed influence zone charts that require the pre knowledge of five well and aquifer parameters. All results are postulated based on programming of Hantush equation for partially penetrating wells.

Select this Article		Tool for Estimation of Additional Drawdown Due to Partially Penetrating Wells in Confined and Semi‐Confined Aquifers Ahmad Wagdy, Hany G. Radwan, and Sherif M. El‐Didy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)169 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a simplified approach for estimating the additional drawdown due to partially penetrating wells in confined and semi‐confined aquifers. Hantush's Equation usually provides acceptable representation of the associated flow field, should this equation be properly solved. An interactive MATLAB ‐based computational program has been developed and verified to provide the analytical solution for the later equation. Results are projected as standard design curves which can be used to determine the total and additional drawdown due to partial penetration for semi‐confined and confined aquifers, respectively. Empirical formulae, commonly used to calculate the additional drawdown in case of steady state flow for confined aquifers are also discussed, and compared with the analytical solution, showing significant differences in many cases. A proposed design chart for steady flow in confined aquifers, along with two families of curves; one for steady flow in leaky aquifers and the other for transient conditions, are thus recommended for well design purposes.

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GROUNDWATER CHARACTERIZATION AND MONITORING

Select this Article		A Novel Approach to Groundwater Model Development Thomas D. Krom and Richard Lane ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)170 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The hydrogeologic conceptual model is a key source of uncertainty in predictions of groundwater flow. The data used to develop the hydrogeologic conceptual model include geologic sample descriptions, interpretations of geophysical data, geochemical information et al. Frequently there is insufficient information to fully describe the hydrogeology without considerable interpretation from an expert. Existing methods for capturing this knowledge rely on the manual interpretation of hydrogeological structures. This procedure is time consuming, difficult to update and also makes it difficult to maintain alternative interpretations of the hydrogeology. We show how hydrogeological models can be created from the 3 and 4‐dimensional data sets using Radial Basis Function (RBF) models. We develop RBF models for the components in a hydrogeological model: aquifers, aquitards, boundaries, drains, and rivers. This approach has significant advantages. Firstly, the models are consistent with the known data and can be automatically updated when new data comes to hand. Secondly, the models can be influenced by both the choice of high level parameters such as anisotropy while maintaining consistency with the data. Thirdly, the user can add manual interpretations (trends or a priori information) that are maintained separately from measurements, but are then merged in the model building process to produce a model consistent with both measured and interpreted data. Once created, the model can be isosurfaced or gridded at any resolution or fitted to any mesh, a process that provides a flexible interface to flow simulators. The methodology will be demonstrated on data from New Zealand and Denmark.

Select this Article		Groundwater Mixing using Pulsed Dipole Injection/Extraction Wells C. R. Radabaugh, D. C. Mays, and R. M. Neupauer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)171 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Mixing is notoriously difficult in groundwater aquifers, because the Reynolds number is very small. This can limit site remediation, and inducing mixing within the groundwater aquifer could speed the chemical processes or otherwise reduce the amount of time needed to meet site remediation goals. A recent analytical model suggests that mixing in groundwater aquifers may be achieved through pulsed dipole injection and extraction from groundwater wells. Building on past work, this study uses MODFLOW, a finite‐difference groundwater flow model code developed by the U.S. Geological Survey, to simulate the flow of groundwater and the movement of particles within a two‐dimensional confined aquifer. The analysis shows the effects of pulsing the wells, modifying the frequency of pulsing, and changing the lag time between pulses. Mixing within the groundwater aquifer is shown graphically through the pathlines of the particles and quantified using Lyapunov exponents to determine if the flow is chaotic based on the positions and paths of particles within the aquifer. The model indicates that the pulsed dipole injection/extraction leads to increased mixing within the aquifer.

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GROUNDWATER MANAGEMENT AND ITS UNCERTAINTY

Select this Article		A Critical Realization Identification Method Based on Pareto Dominance Analysis J. Wang, J. Guan, and M. M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)172 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Stochastic optimization has been frequently applied to groundwater management problems that involve uncertainties associated with hydrogeologic parameters. In this approach, a series of realizations are used to identify the optimal solution. However, this approach can be computationally intensive, especially for field‐scale problems. To alleviate the computational burden associated with these types of stochastic optimization problems, a quantitative procedure identified as Pareto Dominance based Critical Realization Identification (PDCRI) method is developed to screen out the realizations that are most critical to the optimization results prior to the initiation of the optimization calculations. The criticalness of a hydrogeologic parameter realization on the solution is described by its Criticalness Index (CI) value, which is calculated based on a Pareto Dominance analysis. The PDCRI was applied to a hypothetical example to demonstrate its performance. The results show that the PDCRI approach can significantly improve computational efficiency without loss of reliability in optimal solutions and can also be used in other stochastic optimization problems such as optimal remediation system design or groundwater quality monitoring system design under parameter uncertainties.

Select this Article		Combining Rule‐Based Fuzzy Model with GIS to Predict Groundwater Vulnerability to Contamination Dhundi R. Pathak, S. M. ASCE, Akira Hiratsuka, Isao Awata, and Luonan Chen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)173 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The groundwater is the major natural resources for drinking and other various purposes; however, it is under threat of degradation of its quality from concentrated and/or dispersed sources of contamination in urban area of developing countries. Therefore, contamination of groundwater has become a major concern of decision makers and water managers involved with the management of water quantity and quality and their relationship to human health in recent years. Since, groundwater monitoring and mathematical modeling is very costly in regional scale vulnerability assessment, one frequently used water quality protection strategy is to develop contamination potential maps of groundwater, and then prioritize those wells located in the potentially highly contaminated areas for testing of contaminants. However, generation of contamination potential maps is not an easy task due to lack of sufficient hydrogeologic database and inherent uncertainty. This procedure is usually carried out using GIS based overlay index method and process based model. DRASTIC model, a popular index method is used to assess groundwater vulnerability over the large geographical areas on the basis of general hydrogeological knowledge of the contaminant transport in aquifer media. DRASTIC index uses linear model to calculate the vulnerability index and the factors that influence the groundwater vulnerability must be divided into ranges and then be given ratings. This system is unable to describe a continuous transition from the easiest to be polluted to the most difficult to be polluted that is fuzzy nature of the groundwater vulnerability to contamination. Therefore, this paper aims to estimate the risk of an aquifer to be polluted from concentrated and/or dispersed sources which applies the ability of the fuzzy ruled‐based system to cope with the modeling of a nonlinear system and presentation of the output of the fuzzy system in the framework of GIS. This may be possible to describe this concept with a set of linguistics rules in the form of “IF‐THEN”. This paper presents the fuzzy inference system benefiting from fuzzy engine and expert knowledge‐based DRASTIC parameters for nonlinear mapping of the intrinsic groundwater vulnerability concept. The developed fuzzy model is applied to a shallow aquifer of Kathmandu Valley, Nepal and the result is compared with that of the DRASTIC model. This methodology has potential for facilitating groundwater vulnerability modeling at a regional scale and can be used for other regions, especially in the case of data scarcity, however, would require incorporation of appropriate input parameters and rule base suitable for the region.

Select this Article		Evaluation of Alternative Geospatial Models using Image Ranking and Machine Learning: An Application in Shallow Groundwater Recharge and Discharge Yu‐Feng Lin, Peter Bajcsy, Alex Yahja, and Chulyun Kim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)174 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper addresses the problem of accurate estimation of geospatial models from a set of groundwater recharge and discharge maps and from auxiliary remote sensing and terrestrial raster measurements. The motivation for our work is driven by the cost of field measurements, and by the limitations of currently available physics‐based modeling techniques that do not include all relevant variables and allow accurate predictions only at coarse spatial scales. The goal is to improve our understanding of the underlying physical phenomena and increase the accuracy of geospatial models—with a combination of remote sensing, field measurements and physics‐based modeling. Our approach is to process a set of recharge and discharge maps generated from interpolated sparse field measurements using existing physics‐based models, and identify the recharge and discharge map that would be the most suitable for extracting a set of rules between the auxiliary variables of interest and the recharge and discharge map labels. We implemented this approach by ranking recharge and discharge maps using information entropy and mutual information criteria, and then by deriving a set of rules using a machine learning technique, such as the decision tree method. The novelty of our work is in developing a general framework for building geospatial models with the ultimate goal of minimizing cost and maximizing model accuracy. The framework is demonstrated for groundwater recharge and discharge rate models but could be applied to other similar studies, for instance, to understanding hypoxia based on physics‐based models and remotely sensed variables. Furthermore, our key contribution is in designing a ranking method for recharge and discharge maps that allows us to analyze multiple plausible recharge and discharge maps with a different number of zones. This JAVA based software package, Spatial Pattern To Learn (SP2Learn), is designed to be user‐friendly and universal utilities for pattern learning to improve model predictions from sparse measurements by computer‐assisted integration of spatially dense geospatial image data and machine learning of model dependencies. The reliability indices from SP2Learn will improve the traditionally subjective approach to initiating conceptual models by providing objectively quantifiable conceptual bases for further probabilistic and uncertainty analyses. This new approach has been tested using the dataset from Buena Vista Groundwater Basin, a thoroughly understood system in the Central Sand Plains of Wisconsin. This project was supported by the National Center for Supercomputing Applications — Faculty Fellows Program and the Illinois Water Supply Planning Project.

Select this Article		Implementation of the Sustainable Development Concept in the Field of Groundwater Management C. Schöpfer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)175 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable development is defined by the Brundtland Commission as a “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”. Unfortunately, in the public discussion sustainability is often equated with ecology and an intact environment, which doesn't meet this definition. Examinations of sustainability have shown that it has to be put in a context of three partly competing goals: ecology, economy and social affairs. These goals can be described by the so‐called sustainability triangle, in which those solutions that reach a balance among all three goals are sustainable. The approach of sustainable development is being applied more and more often in groundwater management. Development and use of the decision system are presented for two large and intensively used groundwater systems with regards to the water supply. These are a multi‐layered aquifer of unconsolidated rock and an aquifer of consolidated rock.

Select this Article		Projecting Future Groundwater Availability for Power Generation Plant Licensing G. A. Day and C. Krambis, Jr ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)176 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water sustainability is becoming an issue throughout the United States where population and environmental concerns intensify the competition among municipal, agriculture, industrial, and power generation demands. The demand for groundwater has increased beyond its primary historical uses of agriculture and water supply. Viewed as a problem of sustainability, the long‐term challenge for water supplies and regulatory agencies is to maintain steady growth and living standards without compromising the ability of future generations to meet their own needs. Water resource planners must now account for increased power generation needs for a new generation of nuclear power plants that will compete with other demands that typically comprise the existing water availability projections. Planners typically project future groundwater availability using elusive concepts of sustainable yield, safe yield, optimal yield, and consensus yield. These water use projections, resources availability, and allocations are becoming increasingly under scrutiny as demands stretch the available resources and as water consumption decisions are weighed in public policy debates. In this paper, case studies from proposed plant expansions are evaluated for their consideration of groundwater availability.

Select this Article		Simulation of Subsurface Water Flow by Galerkin Finite Element Method in Dhaka City Aquifer Shikha Rahman and Mohammad A. Bhuiyan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)177 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A two‐dimensional mathematical model has been developed using Galerkin finite element method for simulation of transient saturated‐unsaturated groundwater flow in multi‐aquifer system with window based, menu‐driven, user friendly interface to provide on screen input data interpretation, to guide user through steps of data processing, and to generate reports and graphs from output results. The model is able to handle combined and system‐dependent boundary conditions that can be used in practical situation of groundwater flow in the complex hydrogeological conditions of a country like Bangladesh in general and particularly for Dhaka City. Due to less complexity in two‐dimensional simulation and the availability of Graphical User Interface (GUI) the model is easier to use and time efficient.

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GROUNDWATER QUALITY AND HUMAN HEALTH

Select this Article		A Methodology to Reconstruct Groundwater Contamination History with Limited Field Data Jiabao Guan, Morris L. Maslia, and Mustafa M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)178 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A health risk assessment of exposure to contaminants in drinking water frequently requires reconstructing the groundwater contamination history in aquifers. The development of groundwater flow and contaminant fate and transport models used in such an analysis is time‐consuming and expensive. Therefore, new approaches need to be explored to reconstruct groundwater contamination history that may reduce the time and expense of the traditional numerical modeling approaches. An ongoing health study at U.S. Marine Corps Base Camp Lejeune, North Carolina, will determine if an association exists between exposure to contaminated drinking water and birth defects and childhood cancers in children born to women who were pregnant while living at the base during the period 1968–1985. For this study, there are no field data on groundwater contamination at water‐supply wells prior to 1985. Limited contaminant concentration data at several observation wells are available during and after 1992 when remedial investigations of the contaminated aquifers began. To assist the epidemiological study in determining historical exposure scenarios, groundwater contaminant history needs to be reconstructed at base housing areas. Interpreting the mathematical models that are used in the analysis of groundwater flow and contaminant fate and transport and using the field data available on contaminant levels, a linear control model is proposed for the purpose of reconstructing the historical exposure to contaminated groundwater. The control model includes two matrices: (i) the first matrix describes the system behavior of the contaminant movement in aquifers in a natural environment and, (ii) the second matrix reflects the effect of pumping operations on contaminant concentrations. In the control model, the system matrix is recognized by using the least‐squares method and the effect of pumping operations is determined by using an optimization method and an improved genetic algorithm when solving for matrix coefficients. To test the proposed methodology and to demonstrate the effectiveness of the model and proposed algorithm, the Tarawa Terrace base housing area of Camp Lejeune, which has been modeled in detail, is chosen. Computational results show that the model proposed herein can be used as a screening method to recover groundwater contamination history with reasonable accuracy considering the lack of data that may exist at many sites.

Select this Article		A Tale of Two Cities ‐Source Water Protection Case Studies for Systems in Rural Settings Tina Petersen, Ph.D., Camille W. Sowells, P.E., BCEE, Gordon McCurry, Ph.D., P.G., Alexandra Doody, Claudia Krug, and Sean Ables, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)179 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Rural public water supply systems represent the majority of systems in the U.S. Challenges facing the public water supply systems include documented water quality issues such as the presence of coliform bacteria and nitrate and urbanization resulting from development projects in the area. Strategies for dealing with these challenges can vary widely. This paper will present two case studies from a source water protection project being conducted in Central Texas. Both systems are privately owned, rural water system managed by a water supply corporation. Differences between the two systems arise in the populations they serve, with one being a community water system and the other being a non‐community system serving a campground. The paper highlights the unique differences between the two systems in terms of implementation of protection measures as well as funding opportunities.

Select this Article		Quantifying the Spread of Arsenic Contamination in Groundwater of the Brahmaputra Floodplains, Assam, India: A Threat to Public Health of the Region C. Mahanta, N. Pathak, R. Choudhury, P. Borah, and W. Alam ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)180 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Arsenic contamination in groundwater in many countries, including India, has become an issue of global concern. After a relatively recent discovery of arsenic in the upper Brahmaputra floodplains, a Rapid Assessment Program for drinking water in Assam state of India covering all the districts was conducted. The study revealed presence of arsenic beyond permissible limit of 50 ppb in 72 blocks out of 192 blocks spread over 22 districts. A three phase analysis procedure adopted in this study yielded consistent results, showing good analytical performances for a large scale study. Of total 1726 samples spread across 18 districts, a major percentage of samples indicated concentration range of 60 to 150 ppb, emphasizing the need to take up intensive arsenic based research and to develop technologies and water management strategies to provide arsenic free drinking water in the region.

Select this Article		Vadose Zone Transport of Nitrate in the Sierra Pelona Groundwater Basin, Agua Dulce, California Claudia T. Krug and Zbigniew Kabala ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)181 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Using data from previous studies about nitrate contamination in Agua Dulce, CA and the numerical modeling program HYDRUS‐1D, nitrate transport in the vadose zone associated with septic system discharges was evaluated. Thirty‐six modeling scenarios were assessed and the results analyzed. With soil borings less than 6 m deep, steady state nitrate transport within the system is reached within 200 days, while steady state is not reached with the deeper boring within 500 days. The modeling results show that the nitrate concentration plume is less than the maximum contaminant level (MCL) of 10 mg/L within 1.3 m below the septic leachfield in all scenarios. The analysis of the fully‐mixed tank scenario clearly shows that nitrate concentrations in groundwater are of greater concern during drought conditions. These findings help explain the pattern of nitrate concentrations observed in the aquifer system in this region.

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GROUNDWATER QUALITY MODELING—SOLUTE TRANSPORT AND REACTIVE TRANSPORT

Select this Article		Exploring the Potential of Nonlinear and Non‐Equilibrium Alcohol Partitioning for Assessment of DNAPL Source Zone Architecture Rhiannon E. Ervin and C. Andrew Ramsburg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)182 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Recent research highlights the importance of quantifying the relationship between dense nonaqueous phase liquid (DNAPL) spatial distribution, source strength and source longevity. Since acquiring knowledge of the precise distribution of DNAPL saturations (also known as the DNAPL architecture) may be impracticable (technically or economically), attention is being placed on understanding the key features of the DNAPL architecture that control contaminant mass discharge. Examples of metrics describing DNAPL architecture include reactive travel times, spatial moments of the DNAPL mass, and ratios of DNAPL mass present in ganglia to that present in pools. While other metrics may yet be advanced, the utility of any source zone architecture metric as a site management tool requires that the metric be readily quantifiable. Partitioning tracers are one tool that may permit interrogation of DNAPL architecture. Traditional use of partitioning interwell tracer tests, however, provides an estimate of DNAPL saturation that is integrated over the flow path of the tracer. While helpful in estimating overall saturations or total mass of DNAPL, few interwell tracer tests are designed to provide the spatial resolution required to assess DNAPL architecture. Here we explore the use of partitioning tracers under the conditions of nonlinear and non‐equilibrium transport, with the longer‐term goal of estimating DNAPL architecture in localized portions of a source zone. Initial efforts were directed toward elucidating liquid‐liquid equilibria of 2‐octanol, a common partitioning alcohol, in a system comprising water and TCE‐NAPL. Results illustrate the importance of assessing tracer partitioning over a wide range of concentrations. Column experiments were conducted in a sandy medium to explore limitations to tracer transport with both the aqueous phase and a uniformly entrapped nonaqueous phase. These preliminary results suggest nonlinear and non‐equilibrium partitioning may be exploited to assess DNAPL source zone architecture.

Select this Article		Solute Flux Rate Uncertainty Evaluation at a Monitored Boundary David E. Langseth, Sc.D., P.E., D. WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)183 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Limitations on data collection density, aggregated spatial and temporal modeling scales, and variations in time can lead to substantial uncertainty in estimated ground water and solute flux rates. Difficulties associated with quantitative characterization of uncertainty often lead to use of conservative assumptions in management decision‐making processes, which can lead to non‐optimal resource management. This poster describes a computational method for estimating solute flux rate uncertainty at a monitored boundary that can be programmed on an ordinary spreadsheet application and discusses parameter estimation approaches. This method produces results comparable to those produced by Monte Carlo simulation under a reasonable range of assumptions. Two alternative conceptual models at the monitored boundary can be used, one in which the entire area of interest is treated in an integrated manner and the other in which the area of interest is segmented into zones. This poster addresses only the segmented approach. Case study results not shown here indicate that the conceptual model choice has an impact on the analysis results. Use of uncertainty analysis to evaluate likelihood of exceeding target impacts on receiving waters is also illustrated.

Select this Article		An Analytical Solute Transport Model for In‐Situ Estimation of Retardation Gustavious Paul Williams and David Tomasko ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)184 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an analytical model for evaluating a contaminant's in‐situ retardation coefficient from concentration data obtained from an extraction well in a region of initially uniform contamination. Effective retardation estimates are required to effectively evaluate contaminant transport. This estimate often relies on literature values for the distribution coefficient, Kd, and site‐specific estimates for effective porosity, bulk density, and chemical composition of the porous medium. When more accuracy is required, column or field studies may be performed to define a contaminant breakthrough curve which is used to determine retardation. These data can, in many instances, be difficult and expensive to obtain and interpret. In practice, in‐situ retardation coefficients have been frequently evaluated using the results of injection well data and analytical solutions to the governing transport equation in radial coordinates or multi‐dimensional numerical modeling of the transport equation using data from extraction wells. This study presents a solution and method to use extraction well data and the in‐situ contaminant, rather than injection well data and an introduced tracer. Since the solution is based on extraction well data, no tracers or chemicals need to be injected into an aquifer and data from potential remediation wells can be used to obtain these values. In addition to the solution, an integral solution to the instantaneous concentration at the extraction well is presented which allows retardation estimates to be made using only extraction well data and not requiring an observation well. The solution method presented is a numerical inversion of a Laplace transform solution using the Stehfest algorithm to provide non‐dimensional results in real time and space.

Select this Article		Assessing Postulated Accidental Releases of Radioactive Liquid Effluents from Nuclear Power Plants S. W. Taylor, G. A. Day, A. N. Findikakis, G. A. McLane, and L. E. Young ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)185 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Licensing of commercial nuclear power reactors requires an assessment of a postulated accidental release of radioactive liquid effluent in ground and surface waters to demonstrate that the dose to an individual member of the public does not exceed regulatory limits. The radioactive liquid effluent with the highest potential exposure consequences to offsite water users is associated with the liquid waste management system and is comprised of a mixture of fission and activation products with a wide range of half‐lives. The liquid effluent containing tanks postulated to fail are located below ground such that a liquid release would enter the groundwater and then be subject to groundwater transport offsite with radionuclide concentrations being attenuated by the processes of radioactive decay, adsorption, and dispersion. Evaluations of these postulated releases have been completed and included in the license applications for 17 new nuclear power reactor sites. Results of these analyses indicate that groundwater travel times vary widely from site to site and that groundwater to surface water pathways are present for many of the sites. Comparisons of predicted radionuclide concentrations at offsite receptor locations to regulatory limits indicate compliance with the dose limits for an individual member of the public, with tritium having the potential for the greatest dose contribution.

Select this Article		Modeling of Chlorinated VOCs Transport under Dual Bioreactions Wonyong Jang and Mustafa M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)186 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Once chlorinated volatile organic compounds (CVOCs) are released into the subsurface they are spread out through the porous soil matrix by complicated processes such as advection, dispersion, and sorption. CVOCs can be also biodegraded by indigenous microorganism via aerobic and anaerobic bioreactions, which generate distinct benign or harmful by‐products. Heterogeneous subsurface characteristics and non‐uniform distribution and consumption of oxygen in the subsurface may allow the dual bioreactions to coexist within a representative subsurface volume (RSV). The portion of each bioreaction within a RSV will depend on multiple factors such as oxygen, contaminant, and microorganism levels. Oxygen can be supplied into the contaminated zone through the dispersive and advective transport of oxygen in gas phase as well as the flow of the groundwater containing dissolved oxygen. As the dual bioreactions are coupled with multiple fluid flows (groundwater and gas) and multispecies transport, the analysis of the bioreactions is very complicated. However, the enhanced understanding of the dual bioreactions of CVOCs is required in accurately predicting the fate and transport of CVOCs at the contaminated sites. This study numerically investigates: the effects of dual bioreactions on the fate and transport of CVOCs in the variably saturated zone; and, the temporal and spatial evolution of bioreaction zones in the domain. Trichloroethylene is selected as a primary contaminant, and its sequential aerobic/anaerobic bioreactions are considered.

Select this Article		Reaction Rates in a Transport System with Both Kinetic and Equilibrium Reactions Gour‐Tsyh (George) Yeh and Yilin Fang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)187 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The argument of what is the rate of an equilibrium reaction in a transport system is very controversial. It has been argued that the rate of an equilibrium reaction “can be mathematically abstracted as infinity” for the convenience of decoupling equilibrium reactions from kinetic reactions. It has also been argued that the rate of an equilibrium reaction is indefinite. This controversy should not have been aroused at all since, by definition, an equilibrium reaction should not have been associated with a rate per se. We can associate a rate to an equilibrium reaction only if we treat it as an extremely fast kinetic reaction. Then it is legitimate to ask what its rate is. For an extremely fast reaction, its forward and backward rates are asymptotically tending to infinity. The question is then what is its net rate? To answer this question, it is necessary to understand the interplay between transport and reactions. Transport processes and kinetic reactions try to alter the concentrations at each time and at each point of the computational domain. The rates of equilibrium reactions are those rates which are “necessary” to assure that the thermodynamic equations remain fulfilled, i.e., the solution of the concentration field remains on the manifold defined by thermodynamic equations. With this definition of the rates of equilibrium reactions, we can calculate the posteriori equilibrium rates using a subset of decomposed transport equations after all species concentrations are solved. Thus the rate of a fast equilibrium reaction is finite and definite. On the other hand, rates of kinetic reactions require either proposition of reaction pathways or empirical rate equations. Two example problems are used to demonstrate how consistent sets of governing equations are employed to simulate rates of asymptotic kinetic reactions or fast/equilibrium reactions.

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IMPACTS OF URBANIZATION ON GROUNDWATER QUALITY AND QUANTITY

Select this Article		Comparative Study of Two Standard Septic Tank Drain fields Using Different Sand with Recirculation for Nutrient Removal Ni‐Bin Chang, Marty Wanielista, Fahim Hossian, Zhemin Xuan, and Ammarin Daranpob ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)188 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract On‐site Wastewater Treatment System (OWTS) using a septic tank followed by a recirculating sand filter (RSF) with effluent discharged to an unlined standard drain field is a typical performance‐based treatment facility for nutrient removal. The type of effluent distribution in the standard drain field systems include gravity systems, low pressure dosed systems, drip irrigation systems, etc. The standard drain field that is constructed by a series of parallel, underground, perforated pipes allows the septic tank effluent to percolate into the surrounding soil in the vadose (unsaturated) zone where most of the residual nutrients may be assimilated. The inclusion of RSF may improve the nitrification to some extent so as to promote denitrification in the drain field. With such design, most residual nutrients in wastewater are expected to be consumed as the wastewater passes through the soil. This author's aim of this paper is to present the effectivenss of RSF and a comparative study with these two different drain field sands for nutrient removal in vadose zone. They include astatula sand (i.e., citrus grove sand) and washed building sand, popular in Central Florida for drain field use. The use of a gene identification method is novel in supporting the biological removal. Research findings show that the performance of washed building sand and the astatula sand in terms of ultimate nutrient removal is about the same. Because astatula sand is less costly it can possibly be considered for replacement of the more expensive washed building sand.

Select this Article		Environmental Impacts on Surface Water and Groundwater for Expanding Urban Water Supply Capacity Using Stone Quarries Xing Fang, Ni‐Bin Chang, Ming‐Kuo Lee, and Lorraine Wolf ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)189 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Global climate change and its related impacts on water supply are universally recognized. In the past few years, drought impacts affecting big metropolitan water supplies alone have plagued Maryland and the Chesapeake Bay in 2001 through 2002, Lake Mead in Las Vegas in 2000 through 2004, the Peace River and Lake Okeechobee in South Florida in 2006, and Lake Lanier in Atlanta in 2007 that especially affected the water resources distribution in three states — Alabama, Florida, and Georgia. One group of unnatural sites, namely crushed stone quarries, holds promise for expanding the reservoir capacity in water supply systems. Inspired by the past and future trend of global change and the need to generate adaptive water resources management strategies, this study develops the conceptual and numerical framework of a spatial decision support system for evaluating the feasibility of water supply development using abandoned and active stone quarries. Whether or not a particular abandoned or active quarry can be used as a water supply reservoir depends on many different factors. Some important factors are the size of a quarry and the volume of water that can be stored, the location of a quarry and its distance to the city or community that needs water supply, the source of water that can be diverted into a quarry, surface runoff input from watershed to quarry, evaporative loss of water in quarry, and groundwater input to quarry. Water storage and recharge in the aquifers must be achieved with caution since water quality may be changed by biogeochemical reactions with aquifer materials. We demonstrate in two cases that mixing of recharge water and groundwater of different hydrochemistry may dissolve certain minerals while allow others to precipitate in the aquifers. A quarry reservoir can become thermal stratification during summer if it is deep enough, and the stratification can lead to oxygen depletion in the bottom waters, and then it may require hypolimnetic oxygenation (aeration) to improve water quality. A lake water quality model is used to examine water quality dynamics in different types of stone quarry reservoirs under different climate and watershed input scenarios.

Select this Article		Groundwater Baseflow Sourced from Miocene Rocks and Residuals Carries Elevated Selenium into Southern California Streams Barry Hibbs, Mercedes Merino, Rachel Andrus, Wynee Hu, and Anna Doro‐on ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)190 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The geochemical patterns of nitrate and selenium exhibit spatial variability within the shallow aquifer of San Diego Creek Watershed, Orange County California. The surface streams in the watershed are fed primarily by groundwater baseflow from the shallow aquifer. A new area was investigated in the watershed in 2004 and 2005 near “Santa Ana Delhi Channel.” A covariate relationship is shown in the groundwater data collected near Santa Ana Delhi Channel for selenium, nitrate, and salinity. Despite wide scatter of data, there is a clear positive correlation shown between selenium and nitrate concentrations, and a negative correlation between nitrate/specific conductance and selenium/specific conductance. A possible set of hypotheses for the correlative relationships between selenium, nitrate, and salinity are as follows: (1) Geologic history plays an important role in controlling selenium content in the shallow aquifer, and selenium may originate from upland marine shales of Miocene age. (2) A historic marsh in low lying swampy areas of the watershed acted as a sink for selenium in runoff waters. (3) Draining the marsh in the late 1800s changed prevailing hydrologic and geochemical structure of the land, essentially converting this selenium sink to a selenium source whereby infiltrating precipitation and shallow groundwater leaches selenium from the historic marsh deposits. Selenium‐rich groundwater contributes substantial flow to surface streams via groundwater seepage and springs. (4) Oxidation of selenium by nitrate produces a positive correlation between high nitrate and high selenium. (5) Groundwaters with highest salinity in the local areas near Santa Ana Delhi Channel are sourced from lower permeability alkali soils that were never planted to crops, and nitrogen fertilizer was not used on these soils. These fine textured soils were not leached as effectively historically, and retained more salt during leaching, so crops were not planted there. As a result, low selenium, high salinity, low nitrate correlations are observed in areas with saline soils; and high selenium, low salinity, high nitrate correlations are observed in the lower salinity areas where agriculture was practiced.

Select this Article		Investigating the Temperature Effects on Nutrient Removal in Green Sorption Media Ni‐Bin Chang, Marty Wanielista, Devan Henderson, and Ammarin Daranpob ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)191 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract High nitrogen and phosphorus concentrations in stormwater runoff, contaminated groundwater, landfill leachate, and domestic and industrial wastewater effluents have negatively impacted the drinking water quality in many regions. The use of filter media, such as tire crumb, sawdust, sand, clay, zeolite, sulfur, limestone, etc., to get better removal efficiencies of nutrients has been the focus in the planning and design of green infrastructure. These material mixes mainly promote the adsorption/absorption and precipitation of orthophosphate in physicochemical process and the transformation of ammonia, nitrite, and nitrate via oxidation and reduction reactions in the microbiological process. However, temperature changes affect nutrient removal efficiencies in both natural and engineered systems. This paper aims to explore the filtration kinetics of selected filter media for nutrient removal at various temperatures to improve their application potential in all weather conditions. Constitutes of concern include ammonia, nitrite, nitrate, total nitrogen, and orthophosphate. Such a kinetics study leads to investigate the capabilities of comparing a natural soil with soil augmentations in regard to removing nutrients under a range of initial concentrations at three different temperatures (i.e., 28°C, 23°C, and 10° C). Significant differences of removal efficiencies associated with these prespecified temperatures were statistically confirmed by ANOVA analyses.

Select this Article		Nutrient and Pathogen Removal with an Innovative Passive Underground Drainfield for on‐Site Wastewater Treatment Ni‐Bin Chang, Marty Wanielista, Ammarin Daranpob, Fahim Hossian, and Zhemin Xuan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)192 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When urban regions gradually expand due to regional development, centralized sewage collection, treatment, and disposal is often unavailable for both geographic and economic reasons. As a consequence, about a quarter of the residences in the United States relied on decentralized treatment of wastewater. Household wastewater contains high concentration of nutrients (mainly nitrogen and phosphorus), disease‐causing organisms and viruses, and some toxic chemicals. Nation wide, wastewater effluent from on‐site wastewater treatment (OWTS) can represent a large fraction of nutrient loads to groundwater aquifers. Phosphorus and nitrogen compounds are the most frequent measurements to indicate nutrient loadings. Some aquifers may discharge into springs or other surface waters adversely affecting public health. Hence, on‐site wastewater effluent disposal has contributed significant adverse impacts to the dynamics of the natural environment. Nowadays, due to widespread septic tank failure, scientists, engineers, and manufacturers in the wastewater treatment industry have developed a wide range of alternative passive technologies designed to address increasing hydraulic loads, energy saving requirement, and water contamination by nutrients and pathogens in OWTS. This paper aims to present an innovative design of the underground drainfield with soil amendments (sorption media) in a pilot septic tank system. The new system located at the OWTS test center, University of Central Florida (UCF) was tested and proved cost‐effective in the initial test run in fall 2008.

Select this Article		Selection and Prioritization of Best Management Practices for Potential Sources of Contamination in a Wellhead Protection Area Tina Petersen, Ph.D., Camille W. Sowells, P.E., BCEE, Gordon McCurry, Ph.D., P.G., Alexandria Doody, and Sean Ables, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)193 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Implementing best management practices (BMPs) is one of the key outcomes of a successful Source Water Protection program. BMPs are activities that can be implemented to reduce the risk of adverse future impacts to a public water supply. They can include structural activities such as building additional containment around storage vessels and nonstructural activities such as implementing land use restrictions. The objective of this paper is to discuss a new and innovative approach to evaluate, select and prioritize BMPs for multiple public water supply systems in Texas. For this project, a database prioritization and selection tool was developed and used to assist in screening BMPs for multiple public water systems in Texas. The BMP selection process included a three‐tiered screening process that is described in detail. This tool differs from previous US EPA approaches in that it is streamlined and can be applied efficiently for multiple systems.

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INTERACTION OF STREAM AND GROUNDWATER AND INTEGRATED MANAGEMENT

Select this Article		Controlling Saltwater Intrusion to Environmental Sensitive Areas due to the Construction of the Rio Anton Ruiz Flood Control Project David Weston and Rafael Velez ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)194 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Rio Anton Ruiz Flood Control Project was authorized to reduce flood damages to the coastal communities of Punta Santiago, Verde Mar and Villa Palmira, near Humacao, Puerto Rico. Flood damages used to impact those communities throughout the year until the authorized flood control project was built. Historically, flooding occurred when runoff from the mountains within the watershed would flow into a large upland lagoon and then flooded those communities before reaching the Caribbean Sea. The authorized flood control project protected those communities from flooding by the lagoon with a large levee system and a series of canals to the sea. Since the completion of the authorized flood control project in 2001 there have been major impacts to the lagoon and a surrounding environment due to salt water intrusion. Some of the primary impacts have affected Humacao Wildlife Refuge, which has the last major remnant Pterocarpus Forest on the Island of Puerto Rico. That species of tree is endangered and has a low saltwater tolerance, thus requires mainly freshwater to survive. The lagoon has some fish and other plant species such as mangroves that rely on both fresh and saltwater. Therefore, a series of saltwater intrusion measures were developed and constructed to limit the amounts of saltwater that impact the lagoon and the Pterocarpus Forest as a result of the some of the constructed features from the authorized flood control project. This paper will show how the flood control project was developed, illustrate the some of the project oversights and project dynamics that caused the saltwater intrusion problem, and then explain how saltwater intrusion measures were developed with unique construction measures that were required for installation in environmentally sensitive areas.

Select this Article		Estimating Groundwater Seepages to St. Lucie Estuary Gour‐Tsyh Yeh, Jae‐Young Lee, Gordon Hu, and Detong Sun ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)195 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, four analytical models describing hydraulic interaction of stream‐aquifer systems were applied to St Lucie Estuary (SLE) River Estuaries. These are analytical solutions for: (1) flow from a finite aquifer to a canal, (2) flow from an infinite aquifer to a canal, (3) the linearized Laplace system in a seepage surface, and (4) potential flow through stratified unconfined aquifers. Input data for analytical solutions were obtained from monitoring wells and river stages at seepage‐meter sites. Four transects in the study area are available: Club Med, Harbour Ridge, Lutz/MacMillan, and Pendarvis Cove located in the St. Lucie River. The analytical models were first calibrated with seepage meter measurements and then used to estimate of groundwater discharges into St. Lucie River. From this process, analytical relationships between the seepage rate and river stages and/or groundwater tables were established to predict the seasonal and monthly variation in groundwater seepage into SLE. It was found the seepage rate estimations by analytical models agreed well with measured data for some cases but only fair for some other cases. This is not unexpected because analytical solutions have some inherently simplified assumptions, which may be more valid for some cases than the others. From analytical calculations, it is possible to predict approximate seepage rates in the study domain when the assumptions underlying these analytical models are valid. The finite and infinite aquifer models and the linearized Laplace method are good for sites Pendarvis Cove and Lutz/MacMillian, but fair for the other two sites. The stratified unconfined aquifer model gave similarly good agreements with measurements at three sites but poorly at the Club Med site. None of the analytical models presented here can fit the data at this site. To give better estimates at all sites numerical modeling that couple river hydraulics and groundwater flow involving less simplifications of and assumptions for the system may have to be adapted.

Select this Article		Analytical‐Numerical Solution for Seepage along an Earth Canal Disconnected from the Shallow Aquifer Yi Liu and Zhuping Sheng ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)196 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract To have a better understanding of seepage from the canal beds, authors developed a new infiltration method to analyze seepage beneath canal beds during ponding tests. This is distinct from Green‐Ampt method for infiltration on a uniform unsaturated zone and with a constant head in a ponding area. An analytical‐numerical equation was derived to represent the seepage flow based on Darcy's law and Romos' method. Five ponding tests conducted on the selected sections of Franklin Canal in El Paso, Texas were analyzed using the proposed methods. The comparison between analytical solution and other ponding test observation indicated that analytical‐numerical solution gives a good approximation of seepage losses. The annual canal seepage losses vary spatially depending on hydraulic conditions in the canal, ranging from 86,24299,467 m³/km for low flow in the canal, to 177,18564,875 m³/km for high flow, which provide a great potential for water conservation.

Select this Article		Hydrogeologic Investigation for New Water Supply for Water District No. 1 of Johnson County, Kansas J. W. Henson, T. Schrempp, M. B. Horsley, and K. L. Hahn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)197 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water District No. 1 of Johnson County, Kansas (WaterOne) is constructing their Phase V‐A Expansion. The expansion program began with an evaluation of the best source of supply to meet their growing needs. The water supply evaluation included the investigation of horizontal collector wells, which would provide a reliable, high quality supply. A large number of test borings and pumping tests were conducted in the alluvial valleys of the Kansas and Missouri Rivers west of the Kansas City metropolitan area. The results of the testing were used to develop alternative wellfield scenarios. Life‐cycle costs were developed, and this information was used to select the most favorable alternative for WaterOne.

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PROBABILISTIC METHODS FOR AQUIFER PARAMETER ESTIMATION AND GROUNDWATER MODELING AND INVERSE MODELING

Select this Article		A Heuristic Algorithm for Optimal Alignment and Matching of Borehole Stratigraphy Gustavious P. Williams, Norman Jones, and Jeffrey Handy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)198 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an heuristic algorithm, Auto‐Align Boreholes (AAB), that computes near‐optimal stratigraphy sequences from borehole horizons to define subsurface geology in a computationally efficient manner. Matching horizons across boreholes is not trivial and problem complexity grows exponentially with the number of horizons and boreholes. Our algorithm is based on the Smith and Watermen algorithm used in gene sequencing with modifications. Our algorithm computes a near optimal alignment between the horizons, subject to constraints. Matching horizons to develop subsurface models has traditionally been done manually, but for large sets of boreholes, manually selecting the horizons becomes difficult. Other methods exist to compute optimal sequences but they become computationally infeasible for even moderate numbers of boreholes. The optimal alignment problem can be solved exactly by a multiple sequence alignment distance matrix (an exhaustive search method) but is computationally infeasible for even moderate‐sized borehole sets. The literature presents other approaches such as dendrographic algorithms and genetic algorithms. Dendrographic method computational requirements vary with the number of borehole pairs squared (or cubed) and the results depend on the order in which sequences are paired. Genetic algorithms must be run many times to ensure that the solution found is not a local minimum (of which there many) and requires a long runtime if the number of boreholes is relatively large. The AAB algorithm was implemented in the Groundwater Modeling System (GMS), a subsurface pre‐ and post processing system developed by the United States Army Corps of Engineers. The GMS system can compute and present the borehole horizon information to generate subsurface stratigraphic models.

Select this Article		Composite Analysis of Test‐Well and Observation‐Well Data during Constant‐Head Test Yen‐Ju Chen and Hund‐Der Yeh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)199 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A constant‐head test, keeping the buildup or drawdown constant in the test well, is aimed at determining the aquifer parameters. A skin zone around the wellbore due to well drilling or completion has diverse property to the aquifer. Five parameters including the transmissivities and storage coefficients for each of the skin and aquifer zones and the outer radius of the skin zone are determined via the simulated annealing approach to describe the flow system with a finite‐thickness skin. Estimated results indicate that analyzing the single‐well responses, i.e., test‐well flow rate and observation‐well drawdown data separately, is insufficient for obtaining accurate estimates for skin and aquifer parameters. Analysis of specific drawdown in an observation well gives biased results in the negative‐skin case. The skin and aquifer parameters appear to be accurately determined when the flow‐rate and drawdown data are analyzed sequentially or simultaneously.

Select this Article		Wavelet Analysis of Characteristic Length Scales of Permeability in Stationary and Non‐Stationary Porous Media X. Qi and R. M. Neupauer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)200 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Heterogeneity of aquifer permeability has a significant influence on the transport of solutes; therefore accurate characterization of aquifer heterogeneity is needed to reliably predict the behavior of solutes. A critical characteristic of heterogeneity is the characteristic length scale that is a measure of the distance over which property values are correlated. We use two‐dimensional continuous wavelet analysis to identify characteristic length scales of permeability in stationary and non‐stationary porous media. We show that the global and local wavelet energy spectra are the appropriate measures to characterize length scales in stationary and non‐stationary permeability fields, respectively. We demonstrate its effectiveness in identifying the characteristic length scales of two‐dimensional synthetic permeability data.

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EDUCATION

Select this Article		Framing the Design Process in an Undergraduate Environmental Engineering Class Deb O'Bannon, F. ASCE and Tom Kimes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)201 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The environmental engineering core class at the University of Missouri‐Kansas City has introduced a broader definition of “design” to the undergraduate students, and framed the open‐ended work they produce in a design life‐cycle, which is represented graphically.

Select this Article		Integrating Design Heuristics in an Environmental Engineering Course Kathleen M. Leonard ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)202 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Although design courses are mandatory requirements for all accredited engineering schools in the United States, in many cases these courses have become a technical exercise with little integration of management and innovation. As a result, current engineering educational strategies produce technicians lacking the advanced critical thinking and management skills required in the 21^st century business environment. This paper presents a first approach to integrating modules on design heuristics into a mid‐level environmental engineering design course. The goal is to facilitate students' skills in both understanding the mechanics of design and gain practice in research oriented design.

Select this Article		Non‐Traditional University Research Partners that Facilitate Service Learning and Graduate Research for Sustainable Development M. A. Trotz, H. E. Muga, L. D. Phillips, D. Yeh, A. Stuart, and J. R. Mihelcic ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)203 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Goal 7 of the Millennium Development Goals addresses the need for safe water, sanitation, and hygiene by aiming to halve the proportion of people without access to safe water and adequate sanitation from 1990 benchmarks by 2015. One key for successfully integrating university research with global development is to develop strategic partnerships with non‐traditional academic partners that have a strong community presence. Here we use several case studies to demonstrate how these partnerships are integrated with graduate education and research to develop sustainable solutions for global problems. The Master's International Program in Civil & Environmental Engineering at the University of South Florida (USF) provides students with an opportunity to combine their graduate education with service in the U.S. Peace Corps as water/sanitation engineers and an overseas research component. Key features are a 6‐credit research thesis and a 9‐credit, three course sequence in: 1) global public health assessment, 2) applied anthropology, and 3) sustainable engineering technology. Students may also incorporate with their degree a new graduate certificate in Water, Health, and Sustainability. An interdisciplinary graduate course allows students to investigate concepts of sustainability and research methods using a case study focus that focuses on mercury in the Tampa Bay area and a contrasting field based experience in Guyana. Students identify and integrate research approaches across disciplines, implement population surveying methods, and apply simple systems modeling. An NSF research project situated in Bolivia allows undergraduate and doctoral graduate students to work with a non‐government organization and rural community water committees to research issues of water supply, water scarcity, sanitation, and watershed management. The Kiran C. Patel Center for Global solutions at USF also supports activities in this like the facilitation of graduate exchange training exercises with UNESCO‐IHE students.

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EIT POSTERS

Select this Article		A Decision Support System for Beneficial Use of National Dam Water Resources in Swaziland J. I. Matondo and K. M. Msibi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)204 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Government of Swaziland has undertaken the development of water storage and distribution facilities as a process towards overcoming the unevenly distribution of the water resource. However, the current water storage facilities with a total capacity of 720.9×10⁶ m³ can not meet the water demand which stands at 1795×10⁶ m³ annually. The overall objective of this project was to develop an optimum and sustainable decision support tool for water allocation and rationing options for national water reservoirs. A Decision Support System (DSS) is defined as a user‐oriented computer system which supports decision‐makers in addressing unstructured problems. The rationing mode in the developed DSS was used to distribute the available stored water at the beginning of April in order to arrive at a priori predetermined reservoir storage level at the end of October. The DSS has three major components and that is the model input, modeling options and outputs screens. The model input component comprises of technical data (inflow, reservoir level, intended % volume at end of October and allowed lowest rationing %), and policy data (uniform rationing or differential rationing). The modeling options comprise of commands to determine optimum rationing %, provide % rationing and observed dam response and imposed rationing %. The output of the DSS comprises of the optimal rationing (%), monthly reservoir volume from April to end of October as well as a graphical representation of the reservoir response and the final recommendation.

Select this Article		Assessment of Combined Hydroseeding and Coconet Reinforcement to Control Soil Erosion Mervin M. Cereno ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)205 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract At present, the use of inert materials such as concrete and steel had always been relied as for slope stabilization and soil erosion. The widespread of these materials as stone riprap and concrete are now abridged due to its high cost. It is therefore encourage that the use of alternatives such as planting of grass or vegetation along the slopes is the most sensible form of soil erosion control. However, the use of these methods was not much taken into practice which does not account its efficacy for soil stabilization. In this study, the researchers' premise is to congregate information that may be significant to evaluate the performance of Hydroseeding with Coconet in controlling soil erosion and ensuring its suitability and applicability in the protection of the slopes. A representative slope had been constructed and tested at 65° taking an account from the 71.56° of the maximum slope with a 10% factor of safety for both hydroseeding and coconet. A rainfall simulation study was conducted in order to assess the effectiveness of combined Hydroseeding with Coconet against surface run-off to control soil erosion. Performance of Hydroseeding with Coconet were assessed which gave progress to where the soil erosion was to be reduced or controlled. Results from the experiment were expected to give the desired data and outputs to the researchers which should show that combined Hydroseeding and Coconet representative slope yields to control soil erosion and protect the slope.

Select this Article		Designing Effective Rainfall Harvesting Systems in Developing Areas of Sub‐Saharan Africa Emmanuel U. Nzewi, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)206 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper examines the design of rainfall‐harvesting schemes that could be implemented to improve the availability of water in certain developing regions of sub‐Saharan Africa. The focus of the paper is on the evaluation of rainfall distribution patterns in parts of Sub‐Saharan Africa. Rainfall harvesting is a sustainable water supply alternative in the developing, as well as in the developed countries of the world. In the developed regions domestic rainfall harvesting is primarily a means for supplementing other sources of water (usually for non‐potable water uses). This paper also highlights the activities of non‐governmental organizations in the development and implementation of in‐country (location specific) appropriate technologies for water supply. These groups fund and implement small projects which solve basic water and environmental engineering problems in small communities in developing areas. Usually the goal is to use in‐country appropriate technologies to formulate innovative solutions to problems. In a recent study, the National Research Council, identified integrated water management as a high priority development requirement in its list of emerging technologies that would benefit farmers in Sub‐Saharan Africa and South Asia. The study also stressed the need to address water shortage and access to water resources in Sub‐Saharan Africa. Furthermore, the World Health Organization (WHO) estimates that the number of people without access to water services will increase from 300 million (in 2003) to 400 million by the year 2020. This paper will also provide an overview of the water resources inventory and distribution in Sub‐Saharan Africa to emphasize the need for small‐scale, community based water supply alternatives for developing areas in this region. The paper focuses on implementable solutions particularly tailored for the region. These solutions are termed “location‐appropriate” and therefore employ locally available resources, whenever possible, to achieve solutions that are cost‐ effective, sustainable and efficient. It addresses the need to analyze the temporal and spatial variation of precipitation in the design of viable rainfall harvesting systems.

Select this Article		Innovative Design at Lake Lenexa Scott R. Brand, P.E. and Tom A. Jacobs, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)207 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract As new dams get built closer to the public in existing neighborhoods and towns, the Public, through public participation workshops and events are asking for more amenities in the form of parks, recreational facilities, and education seminars be implemented to increase voter satisfaction. The public is also asking for more aesthetic designs if they can be proven cost‐effective at providing an appealing element to new dams. Lake Lenexa was designed and built around the idea of providing for basic dam functions such as flood control, enhanced water quality, recreation but also to provide an inviting community focal point for the residents to visit and enjoy; truly interact with the dam. The residential setting became the impetus for a bigger vision emphasizing bold architecture and aesthetics. Innovative design techniques were implemented to capture the architectural elements of the dam. Extensive architectural elements were incorporated into the dam design including MSE retaining walls, Use of CKD (Cement Kiln Dust), cantilevered spillway bridge, trellis, and a wide variety of landscape architecture. Water quality enhancements were achieved through the use of wetland treatment cells on the upstream tributaries of the reservoir. In addition, several stream restoration projects were completed for the area. The overall project includes the development of three wetlands; trails; recreational and park amenities; and a future amphitheater. Three miles of trails connect the lake to surrounding neighborhoods. The architecturally unique dam and “one of a kind” spillway were designed to symbolize the water cycle as water moves from nature into the urban environment and the back to nature. A pedestrian bridge that spans the spillway offers visitors a good view of cascading pools and a fountain.

Select this Article		Production of Drinking Water from Lake Water Sources with a Nanofilter Membrane to Prevent the Formation of Disinfection Byproducts Rajib Sinha, P.E., Anita Anderson, P.E., Craig Patterson, P.E., and David Pearson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)208 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Small community systems that use surface water as a source of drinking water are frequently faced with elevated levels of naturally‐occurring organic matter (NOM) that are not removed by conventional filtration methods. These residual levels of NOM may combine with chlorine used for disinfection and create disinfection byproducts (DBPs) potentially in excess of the regulatory limit for various DBPs. Frequently, additional treatment for removal of these DBPs is necessary to avoid non‐ compliance with the requirements of the Safe Drinking Water Act (SDWA). The formation of DBPs can be prevented by removing NOM, which acts as a precursor to DBP formation. This paper presents the results of field tests conducted on lake water using a nanofilter membrane, incorporating a method for cleaning the membrane using a foam ball. The system uses a tubular membrane with the ends connected to effectively form a single, long, membrane. The lake water is fed into the inside of the membrane tube and the filtrate is forced out, through the membrane into the membrane housing outlet. Using a timer, a foam ball is periodically passed through the inside of the membrane by reversing the flow direction. This foam ball serves to remove accumulated organic matter capable of fouling the membrane surface. This organic matter is flushed to drain as the foam ball passes through the inside of the tube. The system can be operated with the membrane reject water recycled to the system inlet or in a dead‐end mode where no membrane reject water is produced until the system is foam ball cleaned. Tests were conducted in both modes of operation. The system requires no pretreatment of the feed water other than a coarse (3mm) screen to prevent large solids from entering the system. The effectiveness of the system in producing drinking water was gauged by measuring the turbidity, color, and particle counts of the system inlet and outlet. Tests were also performed using the aerobic spore Bacillus subtilis (B. Subtilis) as a surrogate for bacteria removal.

Select this Article		Rainwater Harvesting Experiences in the Humid Southeast USA Matthew Jones, E.I., Ph.D., William F. Hunt, P.E., Ph.D., and Jason Wright, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)209 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Due to recent concerns over the environmental impact of stormwater runoff and increased water demands, interest in rainwater harvesting systems as an innovative stormwater treatment practice has developed in humid, well developed regions, such as the southeastern United States. Rainwater harvesting systems are designed to capture runoff from rooftops. The captured water can be used as an alternative to municipal or well water for non‐potable applications. The water can be used for irrigation, vehicle washing, toilet flushing, and other non‐potable uses. Harvested water can potentially be used for potable uses with proper treatment. Water harvesting systems can reduce peak flows and pollutant loads as well as conserve valuable resources. In order to better understand the anticipated usage and reliability of rainwater harvesting systems in the southeastern United States, a monitoring study was conducted at 5 rainwater harvesting systems in North Carolina, measuring cistern water levels and rainfall. Harvested water was used for a variety of applications including vehicle washing, irrigation, and toilet flushing. In order for water harvesting to be a viable solution for stormwater management the harvested water must be used between storm events. The system must be drained as much as possible to provide storage and peak flow mitigation for the next storm event. Results of the monitoring study showed that the rainwater harvesting systems were typically underutilized. Water usage was most consistent at the location where harvested rainwater was used to flush a toilet; however, the water level within the cistern only dropped below 80% of capacity on one occasion during the 30 month monitoring period. Research showed that the harvested water may require a dedicated use for water harvesting to be an effective stormwater management tool.

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EMERGING AND INNOVATIVE TECHNOLOGY IN WASTEWATER TREATMENT

Select this Article		Deployable Decentralized Biofilm System to Degrade Organic Carbon, Nutrients and Benzene from Wastewater Dong Chen, Che‐Jen Lin, R. Gavin Jones, Sehul Patel, Rachelle Smith, Thomas G. Chasteen, Micheal Radi, Sabin Holland, Scott A.Waisner, and Jeffery L. Davis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)210 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Decentralized wastewater treatment systems are of great importance to protect the environment and people's health in the areas without centralized treatment system. Utilizing laboratory cultivated inoculating microorganisms (suborder Corynebacterineae including Agrobacterium sp. and Gordonia sp.) in logarithmic growth stage, a deployable aqueous aerobic bioreactor (DAAB) system was developed for decentralized wastewater treatment. The system is flexible, deployable in a standard shipping container, quick to start, and capable of removing organic carbon, phosphorus and benzene from wastewater. Experimental results indicated that the inoculated consortium had a faster COD removal rate than sewage‐born microorganisms during the startup of the system. During the startup period, the removal of total phosphorus in the aeration tank followed a pseudo first‐order kinetics (R² = 0.90) with a rate constant of 0.027 hr ⁻¹. The Agrobacterium sp. are likely responsible for the removal of phosphorus from wastewater. No ammonia removal was found in the aeration tank during the startup phase. After the system was in continuous operation with an average flow rate of 11.4 L/min, the removal efficiency of BOD₅ and total suspended solids (TSS) was 83±32% and 84±9%, respectively. The relative large standard deviation of the removal efficiencies is likely due to the small equalization capacity of a small treatment system to resist the variations of the incoming wastewater quality and shock loads. As an important supplement to the pilot studies, laboratorial tests by headspace analysis showed that the Gordonia sp. were able to degrade benzene from wastewater. After 26 hours, more significant biodegradation of benzene was found in sessile form (57±8%) than in planktonic form (25±11%) with minimal glucose. However, no benzene degradation was found in sessile form when no glucose was provided. The result suggested that the Gordonia sp. could not utilize benzene as the sole carbon and energy source.

Select this Article		Development of Slow‐Release Chemical Oxidation Methods for Environmental Remediation Stephanie Luster‐Teasley, Ph.D. and Patrick Onochie ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)211 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Chemical oxidation (chemox) is an emerging method used for treating subsurface water and soil. In chemox, highly reactive liquids or gases are injected into a contaminated zone where the oxidants rapidly react to oxidize and breakdown subsurface contaminants to less toxic byproducts. Examples of oxidants used in chemox include ozone gas, Fenton's Reagent, and crystalline permanganate or persulfate dissolved in water. Despite the effectiveness of chemical oxidation, there are drawbacks to current chemox technologies. These drawbacks include the need (1) to inject very strong gases or copious volumes of chemox liquids into the ground, (2) to reapply the oxidants into the subsurface to fully clean sites due to side reactions occurring with natural organic matter or plugging of the subsurface system with chemox precipitates, (3) to prevent explosion hazards caused by the rapid reactions, and (4) to protect workers from the health and safety hazards associated with use of these chemicals. A novel approach to improving chemical oxidation treatment is to develop slow‐release, or controlled release systems, to deliver chemical oxidants for water and soil remediation. This paper addresses the development of slow‐release oxidant prototypes which are able to delay the release of a chemical oxidants which can be used for various applications in water treatment.

Select this Article		Peracetic Acid as an Alternative Disinfection Technology for Wet Weather Sewer Overflows E. Coyle, P.E. and L. Ormsbee, P.E., P.H. Ph.D., D.WRE, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)212 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Combined Sewer Overflows (CSOs) continue to be a significant source of wet weather flows (WWFs). Traditional technologies exist to address wet weather overflows but are many times cost prohibitive, can yield toxic by‐products and in areas of older infrastructure, space for facilities to treat overflows is often limited if available at all. As such more cost effective technologies, requiring less space and producing less harmful by‐products are currently being explored. One such possibility for alternative high‐rate disinfection has been investigated using peracetic acid. The decomposition of peracetic acid results in only the non‐toxic by‐products of oxygen, methane, carbon dioxide and water, and the disinfection reaction occurs in a short contact time and with a high kill rate. Thus, this technology can prove not only valuable where space is limited, but is also extremely environmentally sound.

Select this Article		Recycling of Multiple Waste Streams for Transportation Fuel Production via Algae Cultivation at Wastewater Treatment Plants Patrick J. Dunlap and Andrew R. Shaw ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)213 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Increasing oil prices have led to recent initiatives to find domestic and renewable sources of transportation fuels. The cultivation of algae for biofuels production offers a uniquely sustainable option to utilize both greenhouse gases and wastewater as a valuable commodity. Algal cells contain lipids which can be converted to biodiesel by the same processes already used for other feedstocks. The most striking advantage over other feedstocks is the potential of algae; with theoretical production per area much higher than the currently favored feedstocks. Also as a non‐food crop it will not have an effect on global food prices. Furthermore; the non‐oil components of the algae cell also have value, such as cellulose which has the potential to be used for ethanol or methane production. With these advantages in mind, the steady flow of water and nutrients from a wastewater treatment plant presents an opportunity for effluent to be used in algae cultivation. The necessary carbon source could be supplied through a synergistic relationship with coal fired power plants needing to sequester greenhouse gases or as carbon from onsite anaerobic digesters. In any case, the coupling of a wastewater treatment plant with an algae cultivation system offers many exciting opportunities, such as low energy nutrient removal, valuable commodity production, and abatement of greenhouse gases. This paper reviews the current technologies and methods in algae for biofuels production, and suggests the feasibility of their future application to wastewater treatment plants.

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EMERGING AND INNOVATIVE TECHNOLOGY IN WATER TREATMENT

Select this Article		Development of a Community Water Security Filtration System Using Composite Cartridges Nur Muhammad, Ph.D., P.E., Rajib Sinha, P.E., E. Radha Krishnan, P.E., Craig L. Patterson, P.E., Roy C. Haught, Harold H. Harms, and Rick Seville ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)214 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Under a Cooperative Research and Development Agreement (CRADA) established between the U.S. Environmental Protection Agency (EPA) and Harmsco, Inc., a prototype Community Water Security Filtration System for drinking water treatment using composite cartridges is being developed and tested at the EPA's Test & Evaluation (T&E) Facility in Cincinnati, Ohio. The filtration system incorporates a composite cartridge that combines physical pre‐filtration with carbon adsorption and a cyst‐rated final filter for removal of turbidity, specific chemical compounds, and some biological oocysts. The composite cartridge is then followed by ultraviolet (UV) light to provide short wave UV disinfection. The housing is constructed with a tangential inlet that induces a centrifugal motion to the water which aids filtratiom. The research has focused on optimizing the filtration media and housing configuration by testing the system using various biological surrogates and chemical compounds as contaminants. The current system configuration consists of a housing with two chambers; the upper chamber contains 8 (eight) composite cartridges for filtration, while the lower chamber contains six UV lamps for disinfection. Electrodes have been installed between the internal cartridge basket and the housing wall to provide an experimental electroseparation process to enhance particulate and pathogen removal and to determine if there is any pathogen cell disruption. Results of developmental tests conducted on single cartridges to optimize the composite cartridge media configuration show complete removal of Polystyrene Latex (PSL) beads (used as a non‐biological surrogate for Cryptosporidium) which satisfies the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) requirement of >3.0 log reduction of Cryptosporidium. Results of tests conducted on the 8‐chamber full‐scale unit show almost complete removal of MS2 bacteriophage as a surrogate for enteric virus satisfying the LT2ESWTR requirement of a 4‐log reduction for viruses.

Select this Article		Evaluation of a UV/Ozone Treatment Process for Removal of MTBE in Groundwater Supplies in New Mexico Craig Patterson, Fernando Cadena, Rajib Sinha, Dzung Kim Ngo‐Kidd, Abbas Ghassemi, and E. Radha Krishnan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)215 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract EPA's Office of Research and Development is funding pilot‐scale studies on MTBE contaminated groundwater using UV/ozone treatment technology (254 nm UV, 5.8 mg/L ozone). The pilot‐scale treatment system consists of a GW well pump, a feed tank, a pretreatment system (water softener with iron reduction), a low‐pressure UV/ozone treatment system, and GAC post treatment. Treatability studies have been conducted by graduate students at New Mexico State University to determine the effectiveness of UV/ozone treatment on well water contaminated by underground plumes of MTBE and other volatile organic compounds. NMSU found UV/ozone treatment to be highly effective for removing MTBE and MTBE byproducts in groundwater. The MTBE concentrations after treatment were significantly lower (0.4–7.7 μg/L) as compared to the initial influent concentrations (127–251 μg/L). However, acetone was formed during oxidation of MTBE. Future field studies are planned to investigate the impact of enhanced ozone/medium‐pressure UV on MTBE and MTBE byproduct removal and alternative technologies for acetone removal.

Select this Article		Removal of Waterborne Particles by Electrofiltration J. Murphy, Y. Li, R. Ehrhard, K. Carns, C. Patterson, R. Krishnan, and R. Sinha ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)216 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A pilot‐scale evaluation to assess the application of direct current to a rapid sand filter (termed “electrofiltration”) verified the theoretical effectiveness of electrofiltration in enhancing the performance of conventional filtration within a water treatment facility. The efforts which are described in this paper were based on prior bench‐scale assessments of the electrofiltration process. The analysis, combined with the theory used to describe the phenomenon, was used to design and construct the pilot filter using sand from existing filters in the filtration plant. The filter was tested using effluent from a presedimentation basin, at influent turbidities typically around 30 nephlometric turbidity units (NTU). Initial tests verify that electrofiltration can improve the performance of a filter in terms of both particle removal and turbidity reduction. Results from the preliminary analyses and future plans are presented.

Select this Article		Water Distribution Optimization: Taking SCADA One Step Forward Chuck Weber and Simon Bunn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)217 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Implementation of sophisticated SCADA systems in the water industry has given plant operators unprecedented capability to monitor and control all aspects of water production and distribution from a centralized control center. Sophisticated utilities recognize that SCADA need not be composed of one or more isolated “islands of automation” but can and should be a single system operating on a Wide Area Network, and integrated into their enterprise wide information technology system. The next logical step following implementation of a SCADA system is to leverage off this investment using state of the art software to allow predictive as opposed to reactive control of the water system. Resulting benefits can include improving water quality through reduced water age, minimizing energy costs and improved system operations without compromising operational reliability.

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ENVIRONMENTAL CYBER‐SENSING AND MODELING I

Select this Article		ARC Population and Employment Allocation Disaggregator — A Simple GIS‐Based Tool for Parcel‐Scale Population Projection Stephen Bourne, P.E., Mike Alexander, AICP, and Wei Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)218 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Continued development of urban areas requires careful planning to ensure adequate resources are provided for growing industry and population while sustaining a healthy environment. This paper will discuss the on‐going development of a GIS‐based software tool, developed by the Atlanta Regional Commission (ARC), for projecting future development of the Atlanta Metropolitan Region. With this tool, the ARC can model growth of projected populations at fine scales, and thereby estimate future demands for transportation infrastructure, water, and other utilities. The Atlanta metropolitan area is a 22‐county region in the northwest corner of Georgia, with a burgeoning population of approximately 5 million. By land area, Atlanta is the fastest growing city in the world with some of the highest commute times in the United States. Continued development strains Atlanta's resources more and more. The ARC is dedicated to unifying the region's collective resources to prepare for a prosperous future. It does so through professional planning initiatives, the provision of objective information and the involvement of the community in collaborative partnerships.

Select this Article		How to Build a Broadly Useable GIS Toolset for Estuary Analysis Stephen Bourne, Sandra Fox, and Palmer Kinser ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)219 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Assessment of the health of coastal systems is difficult due to complex geomorphology, hydrodynamics and biogeochemistry. Traditionally, this assessment is tackled with commensurately complex supercomputer‐based modeling tools. While these technologies provide useful results, their computational and financial expense renders them unavailable to most coastal professionals. In a pioneer effort to provide a more accessible method of analysis, a GIS‐based database of spatial and temporal data that describe the environment, and an accompanying ESRI ArcMap‐based toolset, together enabling the creation of a “virtual estuary”, were developed for the St. Johns River Water Management District (SJRWMD) in northeast Florida. The project was envisioned to be developed in a two‐phase process. The first, or “Alpha,” phase produced a prototype version, designed by a team composed of academic, government, and industry representatives. To ensure adequate and focused progress, the prototype was designed to tackle a single — but multi‐disciplinary — problem using the virtual estuary, assessment of water quality. As of the writing of this paper, the Alpha phase of development has been completed. The second, or “Beta,” phase (in planning) will put the prototype to the test to tackle several more diverse estuarine analysis problems. In the Beta phase, more institutions will be included to ensure a broad set of problems will be tackled, and to build the user community. This paper will describe the collaborative committee‐based process of project development used in the Alpha phase. The project team was composed of three parts: 1) a project management component — the SJRWMD staff, 2) a research and development component — the consulting water resources software developer, and 3) a design component — the steering committee. The development process consisted of 1) problem identification — assessing the region of influence for water quality sampled in an estuary, 2) a brainstorming session to form an initial set of requirements for what the toolset should do, 3) literature review — to synthesize the state of knowledge on estuary science and methodologies for estuary analysis, 4) rapid development of a prototype, 5) a brainstorming session to reflect on the first prototype and specify more detailed direction for development, 6) final development of the prototype, and 7) documentation of the development process, the prototype solution, and lessons learned.

Select this Article		Predicting CSOs for Real Time Decision Support D. J. Hill, B. Minsker, and A. Schmidt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)220 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a novel data‐driven method for modeling combined sewer overflows (CSOs) in real‐time. This method treats CSO event generation as a threshold process that is triggered by increasingly intense rainfall events, and predicts the likelihood of a CSO given input conditions using a Bayesian network. The fusion of relevant data from multiple agencies into a unified data stream in real time is described, and a hierarchical modeling strategy is proposed that will facilitate the exploration of the causes of CSOs and direct research into the adaptive management of combined sewer systems using the Chicago wastewater system as a case study.

Select this Article		Protocol Considerations to Improve the Reliability of Data Collection in a Radio Telemetry System Daniel Lasorso, Patrick Garrett, and Craig L. Patterson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)221 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In collaboration with Clermont County, the U.S. EPA's Office of Research and Development is developing watershed‐wide load and transport models to account for stream processes at the Experimental Stream Facility (ESF) in Milford, Ohio. To better understand environmental stressors in stream flow and the structure and function of stream ecosystems, researchers are establishing continuous water quality monitoring stations along the Lower East Fork River and its tributaries. River and stream water quality are being automatically monitored and recorded every few minutes for: temperature, pH, dissolved oxygen, conductivity, stream flows (light levels, temperature and humidity), weather conditions (rainfall, solar radiation, temperature, humidity and barometric pressure) using remote sensors and weather stations. To transfer water quality data back to the ESF, high frequency data linking is being investigated for reliably and cost effectiveness. EPA and the University of Cincinnati are examining the existing data telemetry software and suggesting a change in transmission protocol. The new protocol offers two important features: a built in CRC‐16 for error correction and the ability to use the station as a digital repeater. Use of a protocol with a CRC will yield many benefits; the quality of transmitted data will be improved thus allowing the system to utilize higher baud rates, which translates into shorter transmission times and power savings. Use of the new protocol does incur additional packet length to accommodate addressing and the CRC as well as additional computational effort to validate incoming data by computing the CRC, so a comparison of protocols is merited. Also discussed are the benefits of ‘digipeating’ — by allowing each station to act as an addressable repeater transmissions can be broadcast over several hops to extend the range beyond simplex distance with the ultimate goal of meeting the 50 mile specification, though this is subject to the additional considerations of station density and use of directional antennas. Because each station is given a unique address there are possibilities for routing and redundancy in future projects

Select this Article		Visualizing Hydrologic Drought Information on the Web Using State‐of‐the‐Art Geospatial Mapping Technology Jae Ryu, Mark Svoboda, and Jane Okalebo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)222 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Recent advances in web technologies, such as those used by Google Maps, have facilitated the development of more interactive geospatial mapping technologies. The technology behind these mapping tools is known as Asynchronous JavaScript and XML (AJAX), which is aimed at more stable functionality, fast interactivity between servers and clients, and cost‐effective data exchanges between the servers behind the scenes. Although Google Maps takes full advantage of this recent technology, there are still many restrictions in terms of customization, source modification, and licensing issues. We propose to use ka‐Map, which is a very powerful tool for customizing user components such as graphical user interfaces (GUI). Ka‐Map can be coupled with MapServer, which was developed at the University of Minnesota. Since both ka‐Map and MapServer are open source web‐mapping technologies that are compliant with Open Geospatial Consortium (OGC) standards, application of these tools for water resources management is of great interest.

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ENVIRONMENTAL CYBER‐SENSING AND MODELING II

Select this Article		“Let it Rain” — Gage‐Adjusted Radar Rainfall (GARR) Data for Peachtree Creek Sewer Basin Modeling Alberto Bechara, P.E., Jim Moffitt, Vahe Kokorian, P.E., and Rasheed Ahmad, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)223 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sewer hydraulic models are developed to reveal and simulate problem areas in sewer system networks. During model development precipitation input data, typically from rain gages, are applied and system parameters are adjusted until the calibrated model output matches the collected system flow meter data. The calibrated model is later used to evaluate problem areas and identify solutions to the system's deficiencies in order to comply with regulatory requirements, which are met by eliminating surcharge and overflow locations within the sewer system. The study compared the hydraulic models that were developed using a GARR dataset, and a dataset consisting of rain gages only. Both datasets used information from 30 “tipping‐bucket” rain gages from March 2001. The GARR analysis incorporated NEXRAD radar data on a 2×2 km grid, with a 15‐minute sample rate. Correlations between the two precipitation measurement systems were strong. Rainfall timing was well matched. Incorporating the gage volumes resulted in lowering the radar rainfall estimated by 20%. The sewer hydraulic modeling results showed that the Flow (Q), Velocity (V) and Depth (d) response to the flow meter data matched more closely when GARR data is used as compared to the conventional rain gage data.

Select this Article		Adaptive Long‐Term Monitoring at BP Environmental Restoration Sites Matthew Zavislak, John Dustman, and Dennis Beckmann ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)224 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In partnership with BP, Summit Envirosolutions, Inc. has developed a unique set of software tools for reducing costs and improving effectiveness of long‐term monitoring (LTM) through adaptive assessment to achieve remediation goals. There are four components which comprise the software toolset. The first component, EPIPHINY®, is a database platform which gives the user the ability to quickly import and analyze analytical sampling data. The second, ModelBuilder™, creates and visualizes geostatistical models of spatial and temporal data, and identifies areas of significant data uncertainty which may benefit from additional sampling. The third, SampleOptimizer™, identifies redundant sampling locations and frequencies in historical data in preparation for future sampling events. SampleTracker™, the fourth component, enables users to create time‐dependent site‐wide remediation targets (e.g., expected reductions in mass) or well‐specific targets (e.g., expected concentration trends) and to evaluate new data relative to those targets, as well as providing automated alerts of unexpected deviations. This paper presents the long‐term monitoring optimization (LTMO) results for two BP case study sites. The results are presented in the form of tradeoff curves associated with competing objectives: 1) minimizing the number of sampling locations; and 2) minimizing the maximum interpolation errors at all sampling locations which were recommended to be removed, as well as comparative visualizations showing the site concentrations before and after optimization.

Select this Article		Application of Radio Frequency Tracers to Individual and Group Particle Displacement within a Laboratory T. J. Lauth and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)225 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Multiple approaches (shear stress, discharge, stream power, etc.) have been developed for describing the rate of bedload movement, each with a means of being calculated in the field. One current approach relies on the mean virtual velocity of individual sediment particles. Virtual velocity is determined by dividing the displacement length of a particle by the sum of the rest and displacement times. The focus of this research is the application of a Radio Frequency Identification (RFID) system as a means to monitor individual and group particle displacement and rest times necessary for calculating the virtual velocity, so that the bedload transport rate can be predicted. An RFID system consists of programmed transponders and a corresponding reader that communicate using radio waves. This communication provides the ability to track individual particles with embedded transponders. By setting customized antennas in the flume to act as gateways, communication between the antennas and particles traveling over a known distance provides the time between antennas, allowing for the calculation of the 1‐D virtual velocity. To develop this system, multiple obstacles needed to be overcome. Past RFID research has shown that transponder orientation and transponder signal collision can present large problems to the application of RFID technology to sediment transport research. These two problems have been accounted for by: 1) using particles consisting of two transponders oriented perpendicularly to each other, and by 2) using transponders that have anti‐collision signal capabilities. The use of anti‐collision capable transponders also provides the capability of tracking the flux of a group of particles. Tracking a group of particles allows for correction due to the flow field and the possibility of hiding. Cameras and image analysis tools will be used for confirmation of results.

Select this Article		Cost‐Effective Automated Water Quality Monitoring Systems Providing High‐Resolution Data in near Real‐Time Rob Ellison, MS and Mike Cook, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)226 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Automated monitoring systems are providing near real‐time data at very high spatial and temporal resolution at a fraction of the cost of sampling programs. Significant improvements have been made in regards to reliability, maintenance intervals and ease‐of‐use that are making autonomous technologies the most cost‐effective means of environmental monitoring. Data will be presented on the effectiveness of an automated vertical profiling system and a low‐cost, autonomous underwater vehicle (AUV) used to transport a water quality monitoring package through a water column. Data from several case studies in drinking water reservoirs and natural environments throughout the world will be shown. Particular focus will be on the cost benefits of the vertical profiler in drinking water reservoirs and the AUV in environmental mapping applications. The profiling system provides near real‐time data throughout the water column for a number of key water quality parameters such as temperature, algae biomass, turbidity, and dissolved oxygen. The data are being used to optimize water treatment and react to events, resulting in significant cost savings and providing better quality water. The AUV is used for a variety of water quality and bottom mapping applications. Monitoring agencies and consulting firms are using the system to provide very high‐resolution data for point source and non‐point source mapping, side‐scan sonar surveys, and environmental impact projects at a fraction of the cost of current methods.

Select this Article		South Florida Water Control System Tracker: Real‐Time Water Budgeting for Pragmatic Water Control Operations Leslie Gowdish, Ph.D., Stephen Bourne, P.E., Lakin Flowers, Ken Stewart, Ph.D., and Jack Hampson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)227 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The South Florida Water Management District (SFWMD), one of five water management districts in Florida, is responsible for regional flood control, water supply and water quality protection as well as ecosystem restoration in the Southern portion of Florida. The SFWMD is partitioned into water control systems (WCS). Analogous to watersheds in that vertical fluxes of water enter through rain and exit through evapotranspiration, the WCSs differ in that they have control structures to regulate horizontal flux through a system of canals. Efficient control of these structures ensures that SFWMD's multiple water resources objectives are met. SFWMD is currently building an operations decision support system (ODSS) for control of its water‐control systems. A possible source of information for the ODSS is a water‐budget‐based real‐time assessment of WCS system state, which is implemented as the WCS Tracker application.

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INTERDISCIPLINARY EDUCATION PROGRAMS

Select this Article		Coordinating and Implementing a Graduate Course on Interdisciplinary Modeling for Water‐Related Issues Laurel Saito, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)228 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The science and management of water‐related issues is inherently interdisciplinary, involving hydrology, atmospheric science, water quality, geochemistry, sociology, economics, environmental science, and ecology. Although these issues are increasingly being addressed in an interdisciplinary manner, education and training in interdisciplinary approaches in higher education face challenges that include: engaging faculty from different disciplines to teach a course, attracting students from different disciplines to participate in a course, and finding effective teaching approaches that work for diverse academic backgrounds. A graduate‐level course on interdisciplinary modeling for water‐related issues was recently offered by 17 faculty from three institutions with an overall objective of engaging interdisciplinary discourse in modeling aquatic ecosystems. Students were introduced to models available in different disciplines and how such models might be applied together to address water‐related issues, and issues in implementing interdisciplinary approaches. Students also worked in interdisciplinary teams to apply interdisciplinary modeling approaches. This presentation describes the development, implementation, and outcomes of the course, including some of the challenges, rewards, and lessons learned.

Select this Article		Experiences Teaching a Multi‐Disciplinary Course Daniel P. Loucks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)229 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Cornell University offers a two‐year professional masters degree program in public administration. This program attracts participants who have had work experience and interests in furthering their careers in consulting and in government and nongovernmental organizations, mostly dealing with economic development, public finance, and environmental protection. They are an incredibly bright and interesting group of individuals (for example one recent student had 17 years of experience managing the Indian railroad!) but typically they have not had much training in quantitative methods, and specifically model building and use. In fact many will almost do anything to avoid such work. We who plan courses for these individuals have decided that their academic program should include at least three courses in quantitative analyses, including the use of statistics and systems analysis methods. I offer one of these courses that focuses on the art and science of building and solving models to aid in the identification and evaluation of alternative plans or policies for addressing public policy issues and problems.

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RURAL WATER SUPPLY SYSTEMS IN DEVELOPING COUNTRIES

Select this Article		Water Resources in Sudan: Enhancing Rainfall Harvesting Methods for Water Supply S. Mohamed‐Ali, S. Luster‐Teasley, Ph.D., and E. Nzewi, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)230 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In Sudan, the climate ranges from arid in the north and northwest to wet‐and‐dry tropical weather in the southwest. In semi‐arid zones in Sudan such as West region, safe drinking water is rare. In particular, areas in North Darfur and South Kordofan States rely on groundwater supply (wells) or water storage methods called hafir or earth dams for their water supply. Hafir are small lakes constructed in low lying areas to allow water to be stored during rainfall events. Improved water supply methods, to provide adequate water quality and water supply, are acutely needed for this region. Rainfall collection is one of water sources in Sudan and rainwater harvesting (RWH) methods can be implemented to improve the production of crops and livestock in the region. In Sudan, rainfall decreases from south to north, the annual average varying from 120 cm (47 in) in the south to less than 10 cm (4 in) in the north. Agricultural production and domestic water needs would be very difficult to sustain without the use of locally viable rainwater harvesting techniques to enhance water supply; and the reduction of water demand by water conservation. In North Darfur, where the rainfall is concentrated over short periods of time, rainwater harvesting techniques have been developed for various types of water collection schemes by implementing domestic rain water harvesting. The potential to greatly improve water supply and water quality in Sudan exists. This can be achieved by designing and implementing modified rainwater harvesting methods from the United States and other regions that may be applicable in Sudan. This paper presents the water supply problems in Sudan and proposes RWH solutions tailored for the region. It also includes strategies for improving current RWH methods that are being used in developing regions.

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WATER RESOURCES AND ENVIRONMENTAL VISION 2050

Select this Article		Environment and Water Resources in 2050: The Challenge for Engineering Education Jeff R. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)231 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The evolution of the field of environmental and water resources engineering over the next half century will both shape and be shaped by, changes in the formal education of tomorrow's technical workforce in this domain. While predicting anything 40 years into the future is initially daunting and ultimately humbling, this paper presents a framework for anticipating the changes that will be needed in the way we educate environmental engineers. Particular attention is given to the expectation for new and emerging information and computational technologies, and opportunities and challenges for developing new educational pedagogies.

Select this Article		Environmental and Developmental Risks and Stressors Impacting a 2050 Vision Walter M. Grayman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)232 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A vision of what our water resources and environment may look like in the year 2050 must consider the increasing risks and stressors facing our planet. Recent papers, reports and books are used as the source and basis for identifying the range of future challenges facing the world's water resources and environment. They reflect domestic and international views from people in government, academia, institutions, and private practice. The issues have been distilled down into the following major issues/topics: (1) Aging infrastructure; (2) Population growth and demographic shifts; (3) Public health; (4) Economic development; (5) Energy use and production; (6) Climate change; (7) Sustainability; (8) Pollution of our environment; (9) Security; and (10) Institutional issues such as public participation, regulations, environmental justice and utility governance. Each of these topics is assessed in terms of their potential impacts on future water resources and environment and the challenges we will face over the next 40 years in fulfilling a shared vision of the environment and water resources in the year 2050.

Select this Article		Flood Risk Management circa 2050 Gerald Galloway, P.E., Ph.D., Dist. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)233 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Today the United States faces increasing annual flood damages and climate change will only exacerbate this problem. In spite of nearly 73 years of flood control and 41 years of floodplain management, the challenge continues. This paper provides a positive vision of how the floodplain of 2050 might appear if appropriate measures were taken by governments and the public at large in the years ahead. It is based on the output of the 2007 ASFPM (Association of State Floodplain Managers) Foundation Gilbert F. White National Flood Policy Forum that examined this topic.

Select this Article		Urban Stormwater Management in 2050 James P. Heaney and John J. Sansalone ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)234 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract During the past 40 years, urban stormwater management has evolved from focus on drainage and flood control to inclusion of stormwater quality associated with nonpoint pollution. This paper projects what the urban stormwater field could look like in the year 2050. The projections are based on our best judgments as to the internal and external drivers that are expected to change the field during the next 40 years. Relevant projections by other stormwater groups are reviewed. Anticipated changes include the growing interest in stormwater reuse, on‐site control of stormwater using a variety of low impact development alternatives, generation and accretion of recalcitrant residuals, toxics and chemicals as well as changing temporal and spatial phenomena of the urban hydrologic cycle due to changes in climate and patterns of urban settlement. Key expected drivers of changing attitudes are the greatly increasing relative cost of providing water and energy; greater concern about developing more sustainable green materials and infrastructure systems; and technological advances that will allow proactive management of urban stormwater systems using real time control and including source controls.

Select this Article		Urban Water and Wastewater Management in 2050 Glen T. Daigger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)235 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Population growth, coupled with increased standards of living and growing resource limitations, is creating water shortages and necessitates changes form the “linear” urban water management approach historically used. Fortunately, evolving approaches and enabling technologies allow integrated 21^st century urban water management systems to be assembled which require the removal of much less water from the natural environment, can achieve energy neutrality (no net energy input to the water management system), and provide significant nutrient recovery. They incorporate increased efficiency, use of local water resources, and much greater recovery and recycling. These systems provide further advantages, including easier expansion, reduced urban heat island effects, and dramatically increased urban aesthetics. Our existing “linear” systems can be transformed by aggressively incorporating these modern concepts into new developments and when redevelopment occurs. Education and professional practice must be transformed to break down historical barriers between drinking, storm, and waste water. Economic analysis requires careful consideration of marginal effects.

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WATER RESOURCES DISASTERS WAITING TO HAPPEN

Select this Article		Challenges of Managing California's Sacramento‐San Joaquin Delta Jay R. Lund, Ellen Hanak, William E. Fleenor, William A. Bennett, Richard E. Howitt, Jeffrey F. Mount, and Peter B. Moyle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)236 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Sacramento‐San Joaquin Delta is the hub of California's water supply system and the home of numerous native fish species, five of which already are listed as threatened or endangered. The recent rapid decline of populations of many of these fish species has been followed by court rulings restricting water exports from the Delta, focusing public and political attention on one of California's most important and iconic water controversies. In our previous report, Envisioning Futures for the Sacramento—San Joaquin Delta, we explored the alternatives available for the long‐term management of this multifaceted resource. We concluded that change is inevitable for the Delta and that retaining the current policy of exporting large amounts of water through pumps in the southern Delta was both risky and unsustainable. We examined nine long‐term strategies for managing the Delta from the perspectives of environmental, economic, and water supply performance. In this report, we continue the theme of analyzing how the Delta will change in the future and how California can respond to expected changes to meet state economic and environmental objectives. We focus on a central question for long‐term Delta policy: Which water management strategies best meet the goals of environmental sustainability and water supply reliability? Many other decisions concerning California's water management, the Delta aquatic environment, and Delta land use depend on the answer to this question. We provide an integrated analysis of these issues in a series of technical appendices and summarize the results and their policy implications in this report. These analyses allow us to arrive at some firm conclusions regarding the desirability of various long‐term alternatives for the Delta from a scientific and technical perspective.

Select this Article		Characterization of Water Resources and Environmental Disasters Walter M. Grayman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)237 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When you think about water resources and environmental disasters, some of the recent events that come to mind include Hurricane Katrina, the 2004 Indian Ocean tsunami and the Exxon Valdez oil spill. However, other than concluding that “I know a disaster when I see one”, what can we do to better characterize and rank disasters? Some potential criteria include: economic damage, environmental damage, fatalities, reconstruction cost, aesthetic damage, disruption of normal activities, destruction of irreplaceable objects, and long‐term or permanent loss of species. This paper explores past water resources/environmental disasters and provides a rough comparison of their impacts in terms of a range of criteria. It also provides a taxonomy of disasters in terms of causes (natural events, human induced), predictability and potential impacts.

Select this Article		How Reliable is New York City's Water Supply? Daniel P. Loucks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)238 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The New York City water supply system provides drinking water to over 9 million customers. It operates almost entirely by gravity and is delivered to the city via a system of aqueducts and tunnels, some constructed over 100 years ago. Currently the system's safe yield exceeds the demand, but demands are expected to increase, and major system outages are possible, especially in the Delaware water supply aqueduct. NYC receives about 55% of its water supply from the Delaware component of their system. The current leakage from the aqueduct exceeds 40 mgd, and folks living some 700 feet above the tunnel on the surface are seeing new lakes and streams created by that leak. The city is facing a major challenge, how to repair the leaks and not cause a total collapse of the tunnel. This talk will discuss some of those challenges and the possible consequences and options and what is being done about it.

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ENVIRONMENTAL MODELING

Select this Article		Assessing Pollutant Loads and Evaluation of Treatment Systems to Achieve Water Quality Goals for Land Development Projects Steven D. Trinkaus, P.E., CPESC, CPSWQ ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)239 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract It is widely acknowledged that all types of land development have some type of impacts on the environment. Most of these impacts adversely affect our environment, such as those from non‐point sources, such as storm water discharges. In the past 10–15 years, the adverse impacts on water quality from non‐point source pollutants have become very significant. These pollutants have adversely affected our natural and in particular our aquatic environments. Most municipal land use agencies are unaware of the types of pollutants in non‐point source runoff and the negative effects that they have on our environment. The commissions are also not aware how various storm water treatment systems remove pollutants associated with non‐point source runoff. The preparation of a pollutant loading analysis is one tool that can be used to not only determine the amount of pollutants associated with development, but how effective the storm water treatment systems are at the removal of the pollutants.

Select this Article		Characterization of a Perchlorate Contaminated Site Yacoub Najjar, Professor and Sam Mryyan, Environmental Compliance Manager ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)240 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Conventional methods of subsurface assessment for remediation or monitoring purposes often involve field sampling and laboratory analyses of soil and water samples for specific contaminants species. Even though these procedures are well established and produce reliable results, they have a number of disadvantages. Among others, they are not measured in real time, and they are sometimes destructive because excavations are needed to obtain soil samples. Furthermore, the sampling and testing processes can be quite laborious and expensive. Various investigations have been carried out to develop alternative, nondestructive methods for such routine measurements. The application of artificial neural networks (ANN) in environmental site characterization has proved to be an effective modeling method for the prediction of migration paths of environmental contaminants. However, the uses of ANN modeling for the migration of explosives‐related contaminants (in particular perchlorate) in water and soil, have not been widely reported in the literature. For this reason, this study will explore the potential use of neural network modeling for predicting the amount and distribution of perchlorate at military installations.

Select this Article		Numerical Modeling of Ozonation of Organic Chemicals in Surface Water Tingting Zhu, Yafei Jia, Ajit Sadana, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)241 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Ozonation of organic chemicals generally can result in less toxic and more biodegradable products. It is proposed to use ozone as a potential decontaminant in case of chemical spill in surface waters. CCHE2D chemical model, a two‐dimensional depth‐averaged and process‐based chemical fate and transport model, was developed for simulating multiple decontamination tests including two‐chemical‐reaction processes. In this study, toluene decontamination by ozone was selected as an example. Both chemicals' transport, fate and the reactions between these two are all taken into consideration. The model is also used to investigate the effectiveness of decontamination on the water quality by comparing the simulation results of a self‐decay case with scenarios of ozonation. The hypothetical case demonstrated the model's capability to represent not only the chemical fate and transport but also the decontamination operations.

Select this Article		Simulation of Tehran Air Pollution Using Artificial Neural Networks Ali Yazdanpanahrostami, M.Sc. and Kabir Rasouli, M.Sc. student ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)242 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Air pollution is one of the most important environmental issues of the populated cities, which is seriously threatening human health. This is caused by several factors, such as climo‐physiologic characteristics of the region, deficiency of perennial plants, vehicles‐mobile pollution sources‐ and also stationary sources including factories and power plants. Vehicles' gas emission is the major source of air pollution which is related to the type and magnitude of fuel they consume. In comparison, the stationary sources only contribute one fifth of the total pollutant emission. In this study, the effect of fuel consumption increase on Tehran (Iran's capital) air pollution is evaluated. Obviously, weather patterns have also considerable role on air pollution which are considered in the proposed simulation model. For this purpose, the most effective parameters on Tehran air pollution are identified and selected as the input of simulation model. Then, Artificial Neural Network (ANN) models are chosen due to their efficient power and robustness in identifying the nature of complicated phenomena which air pollution is one of them. Tehran is selected as a case study because of its higher violation to the air pollution standards and being one of the five polluted cities around the world. Results show that the proposed model can be implemented successfully to monitor the air pollution changes and consequently makes it possible for associated managers to develop appropriate policies against the air pollution.

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ENVIRONMENTAL PERMITTING

Select this Article		Distributed Power Generation at State Facilities: Economic Analysis of Savings and Carbon Credits Joel G. Burken, A. Curt Elmore, Mariesa Crow, Will Granich, and Trenton Blair ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)243 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract States own numerous dispersed facilities, many in remote locations. These facilities could be potential locations for renewable energy generation systems, using the power to offset the electricity use at the locations with excess being sold back to the utilities, i.e. the grid. In efforts to initiate renewable energy generation at state facilities, the State of Missouri undertook a study to erect a combined photovoltaic (PV) array and wind turbine renewable energy project at a highway patrol facility. In this study, a new rapid site evaluation for wind power potential was undertaken. The annual energy generation was estimated to be 22,800 kilowatt hours (kWh) (12 month × 1,900 kWh/month). The PV/wind turbine system installed and operational in under five months from project initiation. Based upon electricity offsets alone, an economic analysis estimated that the wind turbine part of the project would have a payback period of 18 – 25 years. When considering the Carbon Credits (CC) that could be generated, the payback period was reduced. Carbon Credits are largely an unknown and misunderstood commodity. The current trading price of $3 to $4 per CC equivalent is expected to increase to around $12 in the short term, and within the payback period of this project, carbon credits are anticipated to reach $20–30. Carbon Credit finance is still largely an untested market for entities such as a state, and the economics covered in this talk are not easily attained on small projects. This talk will discuss how agglomeration of the small projects could lead to marketing of these credits to help the economic analysis of the individual projects.

Select this Article		Drive for Zero Net Carbon Impact Jessica Lamb, Presenter, Ashlynn Horras, Presenter, Luke Fencl, Courtney Warren, and Sebastian Medina ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)244 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Today we are challenged with increasing concerns over global climate change, dependency on depleting hydrocarbon forms of energy, the growing scarcity of water resources to support quality of life infrastructure, and sustainability of infrastructure development on natural resources under current technologies and practices. Our future depends upon the development and commercialization of technologies in the field of renewable energy sources for cogeneration or combined heat and power (CHP). These renewable sources could include biomass, biogas, synfuels, and solar power.

Select this Article		Permitting of Confined Animal Feeding Operations: Issues and Challenges William F. Ritter, P.E., F. ASCE and S. Rao Chitikela, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)245 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract EPA implemented new regulations for confined animal feeding operations in 2003. They were revised in 2008 based upon a court decision. Many confined feeding operations above a certain size are required to obtain a NPDES permit under the Clean Water Act. The 40 Code of Federal Regulations Part 122, Section 122.23 describes the permitting requirements for confined animal feeding operations. The paper discusses the main points of the regulations along with some of the challenges in nutrient management planning.

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ENVIRONMENTAL SUSTAINABILITY

Select this Article		A Comparative Study of Water Quality Indices for Karun River S. Ali Mojahedi and J. Attari ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)246 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water quality is an important factor for preservation of human life and aquatic ecosystem. In rivers, water quality is affected by the environment, climate condition, seasonal variation, land‐use, natural and man‐made pollution of watershed. Considering growth of water use for different consumptions and discharge of pollutions in rivers, several water quality parameters are usually monitored along rivers in different periods. However, there is a need to combine results of such measurements in the form of composite indices which are understandable to decision makers and general public. For this purpose, some indices for classification of water quality in rivers have been applied world wide recently. In this paper, two Water Quality Indices (i.e. National Science Foundation of the USA and Council of Ministers of Environment of Canada) were trialed for the case of Karun River system which is the most important river of Iran. These indices were calculated using existing data and their variations have been analyzed and compared in 9 stations, located along the river, for different periods. Results showed that application of these simplified indices was satisfactory for the educational case study and could be replicated for other communities in Iran.

Select this Article		Beyond Compliance and toward Sustainability: Advantages of Systems Environmental Engineering Oral Saulters, Blase Leven, Larry Erickson, John Pickrell, Leslie Jamka, and Ryan Green ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)247 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract New technologies are not only critical in supporting military and industrial success, but also play a significant role in advancing sustainable development. With the current global economic challenges, effective tools and partnerships which streamline the design and dissemination of these technologies are more important than ever. Accordingly, the systems environmental engineering approach utilized by the Urban Operations Laboratory (UOL), [comprised of M2 Technologies, Kansas State University, and CABEM Technologies], has facilitated innovative research, training, assessment, and product design for DoD and other stakeholders. Through strategic life‐cycle environmental assessments (LCEA); programmatic environment, safety, and occupational health evaluations (PESHE); Health Hazard Assessments; and other proactive studies and reports, UOL has helped foster successful development and deployment of non‐lethal technologies. More specifically, these efforts provide a framework for addressing complex environment, safety, and occupational health (ESOH) risks that affect personnel, infrastructure, property, and natural/cultural resources. Integrated analyses (comprehensive and transdisciplinary) involving flexible groups of subject matter experts, are employed in support of public and private collaborations with a focus on inputs, hazards, and constraints. This paper highlights the UOL process which can translate into advantages for a variety of projects (e.g., environmental, water, energy, infrastructure, etc.).

Select this Article		Environmental Impact of Coffee Processing Effluent on the Ecological Integrity of Rivers Found in Gomma Woreda of Jimma Zone, Ethiopia Y. K. Kebede, F. Assefa, and A. Amsalu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)248 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The environmental impact generated from coffee processing effluent was assessed by comparing reference sites with downstream locations. The physico‐chemical parameters of coffee effluent on average consists of very high amount of BOD (2200mg/l), NO₃ (26.4mg/l), low pH (4.3), and zero DO values. Thus, BOD values as high as 1900mg/l and 1700mg/l were found at the downstream sites of Bore and Fite rivers, respectively. The cluster analysis was effective in clustering the downstream sites of Fite and Bore rivers. Based on the principal component analysis, fresh water loving species of Heptagenidae and Hydropsycidae had higher weighted average for oxygen while pollution tolerant species of Chironomidae and Oligocheata had higher weighted average for BOD. The habitat score of the study sites was in the range of 29% (very poor) up to 84% (excellent). In general, the integrity of most of downstream sites was impacted by the coffee processing activity in the area.

Select this Article		How to Save the Second Aral Sea? Rysbekov Yusup Khai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)249 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the beginning of 1960s Aral Sea had water area more than 66000 km². Now Aral Sea was divided into three Seas, and has the total area 20000 km², including Eastern Aral Sea (EAS) − 11000 km², Western Aral Sea (WAS) − 5000 km², Northern Aral Sea (NAS) − 3300 km². Now only NAS (Kazakhstan) has real chances for survival. Preservation of WAS (Uzbekistan) is impossible without creation of artificial flowing ecosystem “WAS − Amu Darya River delta”. There is a line of concomitant factors for benefit for WAS preservation, in comparison with EAS: (1) − WAS has the large depths, the smaller area and water volume; (2) − WAS' water have smaller mineralization. The offered proposal has by innovative part the connection of Western part of NAS with WAS, construction of channel NAS‐WAS and dam, which will separate WAS from EAS. Idea's realization will be favorable for Kazakhstan also.

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ENVIRONMENTAL TRACK POSTER SESSION

Select this Article		Air — Borne Heavy Metal Contamination to River Ganga (India) J. Pandey, K. Shubhashish, and Richa Pandey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)250 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A two year study was undertaken at Ganges basin of India to evaluate the atmospheric input of six heavy metals to river Ganga. Atmospheric bulk deposition was collected on a fortnightly basis at 8 river sites from April 2006 through March 2008 to determine atmospheric loading of heavy metals to river Ganga. The sampling protocol consisted of bulk collectors placed at 24 locations (3 at each site) selected along a 20 km long tract of river Ganga at Varanasi, India. The atmospheric fluxes of six heavy metals to river Ganga were estimated as (g ha⁻¹ y⁻¹) : Cd ‐ 0.56 – 20.15; Cr ‐ 0.34 – 8.87; Cu ‐ 1.63 – 58.17; Ni ‐ 0.21 – 7.32; Pb ‐ 1.80 – 124.00; Zn ‐ 124.15 – 477.18. Atmospheric deposition of all the elements was lowest at Adalpura (site 1) and highest at Rajghat downstream site (site 8) receiving maximum down − wind urban industrial emissions. Zinc alone contributed to more than 68 % of total measured heavy metal input. for season, the atmospheric fluxes were measured highest during winter followed by summer and rainy seasons. Data on heavy metal concentrations in mid − stream water showed significant correlation with their respective values received through atmospheric deposition. Corresponding to the atmospheric deposition, except for Zn, highest concentrations of Cd, Cr, Cu, Ni and Pb in mid − stream were recorded during winter followed by summer and rainy seasons. Concentrations were recorded highest for Zn followed by Ni, Cr, Pb, Cu and Cd. Concentrations of all the heavy metals were high in down − stream sampling locations. Although the concentrations of Cr, Cu and Zn remained well below their maximum admissible concentrations (MAC), more than 80 % of water samples of 7 out of 8 locations sampled, showed Cd, Ni and Pb levels above their respective MAC. Heavy metal loading to mid − stream implicates the adjoining urban agglomeration of Varanasi as the principal emission source area. The atmospheric loading to the river will continue to rise with the completion of Ganga Express highway. This may lead to serious health implications in long − run since Ganga water is also used for drinking purpose by a large population.

Select this Article		The Effect of Sewage Pollutant of Bandar Imam Petrochemical Company on Benthic Macrofauna Community Using Biodiversity Indices and Bioindicators Taybeh Tabatabaie, Fazel Amiri, M. B. Nabavi, M. Sh. Fazeli, and M. Afkhami ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)251 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Macrobenthos are an important part of sea-bed fauna which include Polycheata, Decapoda and Mollusca. Some species of this group are considered as biological indicators for aquatic ecosystem. Macrobenthos are mostly inhabitants without migration and they can be used as indexes of ecological crises related to water. In the present research, benthic community structure in Ghanam creek and region of Mossa creek, It is located around B.I.P.C sewage outlet were studied, eight station were selected, and water & sediment samples were collected in two season warm (September) and cold (February). Result of research indicated that station of sewage outlet around had least species and higher organic matter, on the contrary, the station far from petrochemical industry (station located in Ghanam creek) activities had higher species diversity. Also, present study showed that Polychaetes, reference of pollution bioindicators had higher aboundance. Cosequently, macrobenthic biodiversity relation with dissolved oxyqen and percentage of organic matter in the sediment.

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LANDFILLS AND WASTE TREATMENT

Select this Article		Enzymatic Treatment of a Modified Food Processing Wastewater Anastasia E. M. Chirnside, Assistant Professor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)252 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The wastewater resulting from soy‐processing is found to have extremely high amounts of Total Kjeldahl Nitrogen (TKN), Chemical Oxygen Demand (COD) and a high pH. We have developed an attached growth, packed‐bed bioreactor (PBR) containing the white rot fungus (WRF), Phanerochaete chrysosporium. This fungus secretes enzymes that catalyze oxidation reactions resulting in degradation of recalcitrant compounds. Previous studies utilizing the fungus in the bioreactor found that the high pH of the wastewater caused inhibition of TKN and COD degradation. Adjustment of the wastewater pH before introduction into the bioreactor resulted in a greater reduction of TKN and COD. However, complete degradation did not occur and pH adjustment was required continuously. Thus, we investigated the effectiveness of treating the wastewater with the enzyme culture solution obtained from the reactor instead of utilizing the fungal reactor itself in order to overcome the inhibitory effect of high pH on fungal activity within the reactor. The inorganic forms of nitrogen found in the pH adjusted wastewater were removed by treatment with both anion and cation exchange columns. Diluted wastewater (10% and 20%) was treated with enzyme solution (5% and 10%) and monitored for changes in TKN and COD for 24 hours. There was little change in pH over time for any of the treatments. The COD dropped 50 – 67% for all treatments over 24 hours. Removal of the inorganic nitrogen within the wastewater before treatment with the enzymes resulted in a greater reduction in COD. There was little change in TKN over time for any of the treatments. Treating the wastewater with fungal enzymes successfully reduced the COD concentration by approximately 60%. The results indicate that the use of the ligninolytic enzymes of the white rot fungi to degrade soy‐processing wastewater could be a viable treatment technology.

Select this Article		The Effect of Municipal Landfill Leachate on the Characterization of Fluid Flow through Clay S. Merayyan and A. Hope ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)253 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Federal and state regulations prescribe design requirements for low permeability clay landfill liners based on saturated hydraulic conductivity. The assumption that clay liners are saturated for the duration of their life is a simplification of the true processes at work. The fact that clay liners are compacted to optimum, or just wet of optimum, proves that they are initially subject to unsaturated conditions, and it is well known that liners can remain variably saturated for the duration of their life. While this is appropriate for landfill cover liners, leaching affects may drastically change pore fluid chemistry as water moves through the landfill to the bottom liner. In this study the goal is to determine the affect of modeling two different pore fluids—leachate and water. This research uses an approach that critically assesses how leachate will move through a landfill bottom liner differently than water. The result of this study is the affect of leachate on the soil‐water characteristic curve and a quantitative comparison of how a liner would be expected to perform when permeated with leachate versus water. Samples prepared with leachate resulted in lower water content than samples prepared with water. Both the Van Genuchten and Cory‐Brook models fit the data (leachate and water) very well. At higher (400 cm of water) the difference between the leachate samples and water sample became obvious.

Select this Article		Time Series Analysis of Performance Data from Closed Landfills to Forecast Post Closure Monitoring Needs Banu Sizirici and Berrin Tansel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)254 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A landfill is considered functionally stable when it no longer presents an unacceptable threat to human health and the environment. Landfill stability depends on factors which include variables that relate to operations both before and after the closure of a landfill cell. Therefore, post closure period (PCC) decisions should be based on operational factors, design factors and post‐closure performance data. The question of appropriate PCC period for landfills requires in‐depth case studies focusing on the analysis of the performance data from closed landfills. In this study the performance data from a closed case study landfill was evaluated to forecast the level of stability of a landfill in terms of leachate and gas generation rates and quality. The data was analyzed by time series decomposition technique since seasonality in graphs was identified by regularly spaced peaks and troughs. The data clearly showed the general trend and provided a clear forecast for future planning purposes. Decreasing trends were seen for leachate quantity, landfill gas and methane, chloride, sodium, total dissolved solids, vinyl chloride,1,4‐dichlorobenzene, chlorobenzene, xylenes, ethylbenzene, toluene, total BTEX and cis‐1,2‐dichloroethylene. Increasing trends were seen for iron and bicarbonate. Steady trends were seen for pH, ammonia and benzene. Based on these results, PCC monitoring needs identified for closed case study landfill.

Select this Article		Using Tracers to Derive Sediment Provenance after the Occurrence of a 500‐Year Flood in a Midwestern Stream Kevin D. Denn, A. N. (Thanos) Papanicolaou, and Christopher G. Wilson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)255 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In June 2008, catastrophic flooding of the Cedar River inundated a large portion of downtown Cedar Rapids, Iowa. As a result, floodwaters deposited a large amount of sediment throughout the city. The sediment origin is of intense scientific and public interest due to the quantity of deposited sediment and the potential presence of persistent organic pollutants (PCBs, chlordanes, and synthetic fragrances) attached to the sediment. The primary objective of this study is to determine the temporal and spatial patterns of deposited sediment. Two potential sediment sources have been identified: the bed of the Cedar River and the channel banks. We hypothesize that sediment from the two sources was distributed heterogeneously throughout the city. Therefore, samples were gathered from the two source areas, as well as from terrestrial areas within and adjacent to the flooded region. We will compare the deposited sediment gathered from the terrestrial areas with the sediment obtained from the source areas using natural biogeochemical tracing techniques. The tracing techniques will include an analysis of radionuclides (e.g., ⁷Be, ²¹⁰Pb, ¹³⁷Cs), stable isotopes ratios (e.g., δ¹⁵N and δ¹³C), and elemental ratios (C/N). This comparison will allow us to determine the provenance of the sediment particles, which will assist us in developing a sediment budget for the segment of the Cedar River that flows through downtown Cedar Rapids. Further, we will identify the key processes affecting sediment delivery and redistribution that occurred during the flood. Sediment dynamics during floods is poorly described in the existing scientific literature. The methods established in this study will provide for engineers and researchers the ability to track the transport of sediments in similar floods.

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NUTRIENTS IN THE ENVIRONMENT

Select this Article		Nitrification Inhibition by UVA Photocatalytic TiO₂ Nanoparticles: The Role of Reactive Oxygen Species on Nanotoxicity Okkyoung Choi and Zhiqiang Hu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)256 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract We measured the toxicity of TiO₂ nanoparticles to nitrifying bacteria under ultraviolet conditions. Nitrifying bacteria play an important role of nitrification in wastewater treatment plants. Although there was no inhibitory effect of TiO₂ nanoparticles under ambient light or dark conditions, nitrification inhibition was significantly increased when TiO₂ nanoparticles were exposed to ultraviolet (UV) for 30 minutes. Under UV exposure, both TiO₂ nanoparticles and bulk TiO₂ generated the same amount of reactive oxygen species (ROS) in the cells although TiO₂ nanoparticles were more toxic than the bulk counterpart. While the inhibition was well correlated to intracellular ROS concentration, the ROS correlations were different for the different forms of TiO₂ or for the different nanoparticles (e.g., Ag vs. TiO₂), indicating that ROS is not a good chemical marker of the toxicity of nanoparticles.

Select this Article		The Economic and Environmental Significance of Nonpoint Source Abatement in Large Watersheds Jamie Lefkowitz, Kirk Westphal, P.E., Jeffrey Walker, and Gary Mercer, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)257 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Throughout the United States, nonpoint source pollution from stormwater runoff, failing septic tanks and other diverse sources is a significant, often dominant, cause of noncompliance with water quality standards in large watersheds. Even with this knowledge, considerable economic resources are spent on reduction of conventional point source pollution (e.g., wastewater discharges and combined sewer overflows) with little more than a casual understanding of the nonpoint source pollution sources within a large watershed, or of the potential value of dollars spent, as measured by improvements in receiving water quality or designated use attainability. This work shows that quantification of nonpoint sources and their influence on regulatory compliance should be at the forefront of watershed management efforts, not as a replacement for point source abatement, but as a factor worthy of equivalent scientific and economic attention. With this guiding principle, this work illustrates how abatement costs and resulting environmental improvements for both point and nonpoint source controls must be clearly understood and managed together if the fundamental precepts and objectives of the Clean Water Act are to be addressed decisively.

Select this Article		The Nitrogen Budget of DRW in the Northeastern China Chengwei Han and Shiguo Xu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)258 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The nitrogen (N) budget is studied to evaluate N inputs and outputs of DHF Reservoir Watershed (DRW), where it is cold semiarid climate in northeastern China. Using the data of 2003 as a typical calculation year, the input of N is quantified from the aspects of atmospheric deposition, fertilizer use, biological fixation, net food and feed input, output of N from ammonia volatilization, denitrification and runoff export, respectively. It is addressed that the atmosphere deposition, fertilizer use and food and feed input dominates more than 90% of the total input. In the output side of N, the ammonia volatilization and denitrification are the main items, which account for 55% of the total N input and 95.1% of the total N output. However runoff N export is 6.49% of the total N input. This is owing to the more water retention time in reservoir for N settling and more sites for denitrification. Over the whole watershed, the budget of N is positive (13.52 kg ha⁻¹ yr⁻¹), which results in the N accumulation in landscape and the TN concentration increase in DHF Reservoir.

Select this Article		Wastewater Utilities: Are You Ready for Kansas' Nutrient Removal Policy? Heather Phillips and Katie Funderburk ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)259 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In 2004, the EPA mandated all states to develop Action Plans and nutrient water quality criteria to rehabilitate impaired waters. In accordance with this mandate, the Kansas Department of Health and Environment (KDHE) has developed a nutrient removal policy whereby wastewater treatment plants (WWTP) with capacity greater than 1 mgd must meet technology based biological nutrient removal (BNR) goals to concentrations of 8 mg/L total nitrogen (TN) and 1.5 mg/L total phosphorus (TP). These guidelines were set to achieve the recommended overall nitrogen and phosphorus reduction of 30% for the State's lakes and streams (KDHE Water Bureau, 2004). This total reduction will involve best management practices for non‐point sources as well as the previously stated goals for the point source contributors. This paper will discuss the key issues of BNR upgrades in Kansas: (1) capital costs, (2) data collection, (3) staff requirements, (4) operating costs, and (5) sustainability. While other states have established enhanced nutrient removal (ENR) or limit‐of‐technology (LOT) standards for severely impaired waters, the state of water quality in Kansas enables most utilities to upgrade their systems for BNR goals. This provides essential time for planning, training, and funding, while improving the overall water quality in Kansas.

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SOIL AND SUBSURFACE REMEDIATION 1

Select this Article		Application of Biopile System for the Remediation of Petroleum‐Hydrocarbon Contaminated Soils C. M. Kao, H. Y. Chien, Rao Y. Surampalli, and W. P. Sung ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)260 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this study was to assess the potential of applying enhanced bioremediation on the treatment of petroleum‐hydrocarbon contaminated soils. Microcosm experiments were conducted to determine the optimal biodegradation conditions. The control factors included oxygen content, nutrient addition, addition of commercially available mixed microbial inocula, addition of wood chips and rice husks (volume ratio = 1:1) as bulking agents, and addition of organic amendments (chicken manures). Results indicate that the supplement of microbial inocula or chicken manures could significantly increase the microbial populations in soils, and thus, enhance the efficiency of total petroleum hydrocarbon (TPH) removal (initial TPH = 5,500 mg/kg). The highest first‐order TPH decay rate and removal ratio were approximately 0.015 day⁻¹ and 85%, respectively, observed in microcosms containing microbial inocula (mass ratio of soil to inocula = 50:1), nutrient, and bulking agent (volume ratio of soil to bulking agent = 10 to 1) during 155 days of incubation. Results indicate that the first‐order TPH decay rates of 0.015 and 0.0142 day⁻¹ can be obtained with the addition of microbial inocula and chicken manures, respectively, compared with the decay rate of 0.0069 day⁻¹ under intrinsic conditions. Thus, chicken manures have the potential to be used as substitutes of commercial microbial inocula. The decay rate and removal ratio can be further enhanced to 0.0196 day⁻¹ and 87%, respectively, with frequent soil shaking and air replacement. Results will be useful in designing an ex‐situ soil bioremediation systems (e.g., biopile, landfarming) for practical application.

Select this Article		Peroxidase‐Mediated Stabilization of 2,4‐Dichlorophenol in a Model Humin‐Mineral Geomaterial Mónica Palomo and Alok Bhandari ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)261 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Enhanced polymerization of phenolic contaminants induced by the application of the enzyme horseradish peroxidase (HRP) has drawn attention of many researchers due to its potential for remediation of contaminated soils. This study utilized 2,4‐dichlorophenol (DCP) as a probe solute to evaluate the ability of HRP to stabilize pesticide derivatives in a model humin‐mineral geomaterial. The model soil was derived from a natural surface soil treated with alkali to remove humic and fulvic acids. The resulting humin‐mineral material had SOM content and chemical characteristics that were different from the parent soil. Sorption of DCP was complete within 24 hrs and most of the sorbed DCP was removed from the geomaterial by water and methanol suggesting weak solute‐sorbent interactions. Phase distribution of DCP polymerization products (DPP) also appeared to be complete within 24 hrs, but a significantly higher amount of the solute was stabilized in the presence of HRP. The total extractable solute decreased, and DPP bound residues increased with contact time and initial solute concentration. These results illustrate the potential of utilizing HRP‐mediated oxidation for in situ stabilization of pesticide derivatives, such as DCP, in humin‐mineral geomaterials representative of soils found below the root zone.

Select this Article		pH Variation and Its Effect on Metal Concentration during Electrokinetics Ming Xiao, Ph.D., P.E., M. ASCE, Ashleigh D. Love, and Zheng Teng, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)262 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Heavy metal contaminated soils pose significant threat to the environment and human health. Electrokinetic remediation is an emerging remedial technology that removes the contaminants from silty or clayey soils by applying an electric potential across contaminated and saturated soils using a pair of electrodes. The anode attracts negatively charged contaminants, and the cathode attracts positively charged contaminants, such as heavy metal ions. When the cationic contaminants reach the cathode, they can be pumped out with the contaminated water and disposed or treated safely. However, the electrokinetics is complicated by the metal precipitation before the metal ions can reach the cathode. This is caused by electrolysis that occurs at both electrodes. At the anode, water is oxidized, releasing oxygen and creating H⁺ that results in an acid front moving towards the cathode. At the cathode, hydrogen is evolved and a base front of hydroxyl ions (OH⁻) is generated and moves to the anode. The metal ions migrating toward the cathode tend to react with OH⁻ when they reach the base front to form metal hydroxides, which precipitate from the pore fluid as solid form.

Select this Article		Pore‐Scale Characterization of Residual Non‐Aqueous Phase Liquids (NAPLs) in Fractional Wettability Porous Media Riyadh I. Al‐Raoush ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)263 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this research was to investigate the impact of wettability of porous media on pore‐scale characteristics of residual non‐aqueous phase liquids (NAPLs). Synchrotron X‐ray microtomography was used to obtain high‐resolution 3D images of fractional wettability sand systems. Pore‐scale characteristics of NAPL blobs such as volumes, lengths, interfacial areas and shape factors were computed from the 3D images. Four systems of different NAPL‐wet mass fractions containing the residual NAPL were imaged and analyzed. In systems comprised of 100%, 50%, 25%, and 0% NAPL‐wet mass fractions, residual NAPL saturations were 0.125, 0.067, 0.083, and 0.121; mean blob volumes normalized by the volume of a sphere with mean grain diameter were 0.97, 1.23, 1.93, and 2.39; normalized mean blob interfacial areas were 43.75, 35.86, 34.25, and 30.88 mm⁻¹; and mean sphericity index values were 0.216, 0.262, 0.455, and 0.569, respectively. Findings revealed that spatial variation in the wettability of porous media surfaces has a significant impact on pore‐scale characteristics of residual NAPL blobs in saturated porous media systems.

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SOIL AND SUBSURFACE REMEDIATION 2

Select this Article		Addressing Contaminated Groundwater and Promoting Environmental Stewardship in Wichita, Kansas — The Gilbert and Mosley Project Story Paul Anderson, P.E., Shawn Maloney, P.G., and Roger Olsen, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)264 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Wichita, Kansas faced a significant environmental challenge when volatile organic compounds impacted a large volume of groundwater extending south of the downtown area to the Arkansas River. This contaminated groundwater posed a threat to human health and the environment and threatened to stagnate economic development as a result of the environmental liability concerns across the project area that encompasses about 3,850 acres and 8,000 parcels of residential, commercial, and industrial properties. The City, with CDM's assistance, investigated the contaminated groundwater, designed and built a groundwater treatment system to protect human health and the environment, and designed and built the Wichita Area Treatment, Education, and Remediation Center (WATER Center) to provide environmental education resources for the entire Wichita community. The City has turned an environmental liability that threatened human health into an environmental education resource for current and future generations.

Select this Article		Use of In‐Planta Solid Phase Sampling Devices to Delineate VOC Plumes Joel Burken, Kendra Waltermire, and Emily Sheehan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)265 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Plants directly interact with surrounding water, air, and soil, collecting and storing chemicals and elements from the surrounding environment. Two new and innovative sampling methods in which this valuable data can be accessed to replace as well as supplement contaminated‐site investigations have been developed. When determining the extent of the plume on a contaminated site, groundwater sampling may be limited due to time, site access, and expense. By using new techniques that place sampling devices inside the trees on site, we can sample trees naturally occurring on a contaminated site or those planted in phytoremediation or redevelopment efforts, evaluate the plume size, and even monitor changes in concentration. These methods will have a minimal footprint and can be accomplished with little materials cost, time, or labor demands. These quick sampling techniques can provide an array of data within a short amount of time to help the efficiency in placement of groundwater monitoring wells, saving time and money as well as undue impact to the ecosystems at hand or personal property.

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SOIL AND SUBSURFACE REMEDIATION 3

Select this Article		Application of a Mass Balance‐Based Subsurface Contaminant Transport Model Benjamin W. Johnson, E.I., Andrew Curtis Elmore, Ph.D., P.E., M. ASCE, and Jeffrey D. Cawlfield, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)266 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The definition of contaminant source release is a necessary element of contaminant mass transport simulation in the saturated zone. At many sites the release history is unknown, and there has been a significant body of research to develop inverse models to define finite release histories. Instead of rigorously defining the source history, a mass balance‐based approach is tested to explicitly account for uncertainty in equal length rectangular pulse release variables. The approach has been incorporated into a spreadsheet model which uses a one‐dimensional solution to the advection dispersion equation. A concentration dataset collected at a Superfund site was used for model calibration and verification. Several synthetic datasets with known input parameters were also used for model calibration and verification. The model provided reasonable results when the source time parameters were assumed to be random, and the results improved when the mass of contaminant in the aquifer was also assumed to be random. However, the improvements came at the cost of degraded calibration parameter values.

Select this Article		Associations of PAHs with Size Fractionated Sediment Particles Jejal Reddy Bathi, Robert Pitt, and Shirley E. Clark ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)267 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sediment samples were collected from three different locations and analyzed for selected parameters to study the effects of selected sediment characteristics and contributing source areas on sediment PAHs concentration. For all cases, the particles in the size range of 180 to 355 μm were most dominant in the sediments. Sediment COD, percent of material weight loss on ignition (material composition analysis) and sediment PAH concentrations showed similar trends of smaller and larger particles associations with higher values than with the intermediate sizes. However, most of the mass of the PAHs were associated with the smaller and intermediate sized particles. Sediments affected by commercial area runoff were found to have higher concentration of PAHs than the sediments affected by noncommercial area runoff.

Select this Article		Sorption and Desorption of Testosterone in Agricultural Soils Rui Ma and Tian C. Zhang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)268 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Several studies regarding sorption and dissipation of testosterone in soils have been conducted recently; these studies concluded that the transport of testosterone is limited in the soil/water system. However, this may not explain wide occurrences of testosterone in ground and surface water. In this study, soils from two agricultural fields located in Nebraska, with 3 depths in each location, were utilized to study sorption and desorption of testosterone. The sorption results of batch tests indicated that the Freundlich sorption capacity of the soils ranged from 8.53–38.82 μg¹⁻ⁿmLⁿg⁻¹. The results of desorption experiments indicated that after 3 washes by hormone free distilled water, about 35.14– 102.35 % of the testosterone adsorbed onto the soil in the adsorption tests were desorbed from the soil. Correlations between sorption and soil properties such as cation exchange capacity, surface area, and soil organic matter were investigated. Also, the behavior of sorption and desorption of soils at different depths was compared.

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WETLAND MITIGATION AND WATER MANAGEMENT

Select this Article		A Study on Spatial Distribution of Water Quality and the Behavior of Do Concentration in Tidal Area of Urban Rivers M. Okabe, M. Kawamura, T. Kato, and T. Yamada ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)269 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The aims of these observations are to clarify the urban river water quality in tidal area. This paper explains the spatial distribution of water quality in the tidal area during normal water discharge and the time series of the dissolved oxygen content before and after the flood. This is the basic research to improve water quality. From the results of the observation, following results are obtained; 1) BOD concentration meets the environmental criteria in Japan. 2) T‐N and T‐P concentrations rise at the observation points below the discharge points from the water reclamation centers. 3) In the observation during rainfall, the dissolved oxygen saturation decreases from 20% to below 5% at observation point in two hours, and the value recovered after 6 days to recover up. Moreover other observation, dissolved oxygen rises to around 100% in all layers.

Select this Article		Development of an Amphibian Biotic Index to Evaluate Wetland Health in Northern Missouri C. D. Shulse, R. D. Semlitsch, and K. M. Trauth ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)270 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Most amphibians require suitable wetlands for breeding, oviposition, and juvenile development. Newly metamorphosed juveniles disperse into terrestrial habitat where they spend the majority of their adult lives in undisturbed forest or grassland adjacent to the wetland. Development of new infrastructure can result in wetland draining and habitat fragmentation thereby disrupting necessary life history functions. To ensure the long‐term survival of amphibians, it is imperative that developers take into account their conservation needs during project planning and construction of replacement wetlands. In order to assist planners and managers in this effort, we present an index that quantifies the biotic integrity of amphibian populations within constructed wetlands throughout northern Missouri. The index is modeled after Ohio's Amphibian Quality Assessment Index (AQAI) and it incorporates ecological and abundance information for each species inhabiting a wetland. Although refinements will continue, current results indicate this tool can help assess the biological integrity of constructed and natural wetlands. The index can be modified to accommodate regional differences in species' ecology.

Select this Article		GIS‐Based Landscape Parameters for Wetland Evaluation Related to Amphibian Health Miriam Romero, P.E., Kathleen M. Trauth, Ph.D., P.E., M. ASCE, Yingkui Li, Ph.D., Raymond Semlitsch, Ph.D., and Christopher D. Shulse ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)271 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Infrastructure decisions for transportation include where to locate rights‐of‐way (ROWs) for new transportation routes. These new routes can impact wetlands by replacing them with roadways and by impacting the landscape that supports biodiversity within the wetland. State departments of transportation (DOTs) need guidance for how to evaluate alternative ROWs in light of the potential impact on wetlands. Because a wetland and the surrounding landscape are spatial in nature, they are well‐suited to analysis via a geographic information system (GIS). Many landscape parameters can be devised and information layers developed. Meaningful information layers are those that describe the impact that the landscape has on the amphibian life cycle. An interdisciplinary research team from the University of Missouri and the Missouri Department of Transportation (MoDOT) brings the unique perspectives of civil engineering, geography and biological sciences to bear on this problem. At the “micro” scale, amphibian species and abundance have been sampled within 49 constructed wetlands in northern Missouri. These data has been analyzed from the biological perspective to create a habitat quality rating for each wetland, considering that some species are more sensitive to wetland changes, with their presence indicating a higher quality environment. This rating provides the dependent variable, y, for the creation of a regression equation relating landscape parameters to amphibian health, and thus wetland quality, at a “macro” scale. As a first step in developing a regression equation, appropriate GIS variables must be developed. Factors such as land cover, and the presence or absence of roads and streams have been identified as being important to amphibian health. However, one cannot simply utilize layers of land cover, because the important factor is how the amphibians interact with the landscape. This paper focuses on the effort to devise a set of GIS parameters that accurately represent amphibian interactions with the landscape. There are a number of important requirements for this amphibian‐based GIS analysis. In addition, amphibians first encounter those landscape conditions that are closer to the wetland, so greater importance is associated with nearer features. Because migrating adult or dispersing juvenile amphibians may travel from a wetland in any direction, the analysis must be performed on landscape parameters that occur within discrete “quadrants” or portions of quadrants radiating out from a wetland. In addition, earlier encounters can impact how other features are evaluated, so the context and location of conditions is important, and features must be evaluated from inner to outer locations in a sequential fashion. For example, if an amphibian encounters an interstate highway that constitutes an absolute barrier, then a forested area on the other side of the road has no value because it cannot be used to benefit the amphibians. Lastly, a parameter such as access to water can induce both positive and negative impacts, and the GIS parameter must represent this duality. With appropriate GIS parameters, the regression equation can be developed and used to inform the selection of ROWs to avoid locations that provide important habitat for amphibians.

Select this Article		The Rush Creek Detention Facility Planning a Permanent BMP in the Real World I. M. William Yord, P.E., A. M. ASCE, Joe Ennett, and Jerry Richardson, M. ASCE, D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)272 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Weatherby Lake is one of the cleanest lakes in the State of Missouri. According to test samples of TMDL, phosphorous, heavy metals, and other pollutants, the water quality of Weatherby Lake is comparable to many pristine lakes in Canada. Development upstream of Weatherby Lake in the Platte County area in recent years has threatened the water quality of Weatherby Lake and has prompted action by the Weatherby Lake Improvement Company (WLIC) to take a positive pro‐active role in the protection of this natural resource.

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BRIDGE SCOUR

Select this Article		General Hydraulic Characteristics of an Open Channel with Narrow Path M. S. Quimpo and T. Yamada ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)273 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This study uses laboratory and theoretical experiments considering upstream, narrow and downstream sections of the channel in its normal and inundated state conditions. In a normal state condition, results proved that as the cross‐section of a channel decreases, the higher the velocity and maximum water depth occurs. Asymmetry of flow was caused by the occurrence of different velocities and pressures at the exit right and left sides section of a narrow path and was dependent on the initial boundary conditions applied at upstream section of the channel. On the other hand, bank overflow starts to inundate where maximum water depth occurs during the normal state condition then goes to the floodplain upstream side direction. Moreover, Ishikawa's theoretical overflow equation correlates with the laboratory and theoretical results. Understanding the flow characteristics of a channel will allow us to predict and identify the direction and extent of damage in case of flood.

Select this Article		Mathematical Modeling of Bed — Topography Changes at Bridge Abutments Omer Kose and A. Melih Yanmaz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)274 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract River bridges are very important elements of transportation systems, failures of which may not only lead to loss of several lives and excessive damages but also various deficiencies including socio‐economic factors. Several aspects of bridge failures should be investigated jointly to gather information for scour‐resistant design practices. This study specifically focuses on the effect of clear water scouring at vertical‐wall abutments on bridge stability. Determination of the time‐dependent volume and surface area of scour hole around a vertical‐wall abutment would yield relevant information to assess the safety level of the bridge foundation. To this end, temporal variation of geometric features of scour holes around vertical abutments under clear water conditions are examined with reference to an experimental study. Findings of this study would yield some information concerning loss of structural resistance, safe design of footing and sizing and placement details of armoring countermeasures against scouring.

Select this Article		Predicting Rock Scour in an Alluvial River with a One‐Dimensional Model Blair P. Greimann, Yong G. Lai, and Kuowei Wu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)275 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Taiwan rivers generally have steep slopes, are subject to high flows, have frequent earthquake activity, and have relatively weak bedrock. Bedrock is often exposed and rock scour is an important river process. For example, the river channel downstream of the Shih‐Gang on the Tachia River experienced severe rock scour since the Chi‐Chi earthquake of 1999 uplifted a portion of the river approximately 10 m. The occurrence of deep rock scour has been a major threat to river infrastructure at many other locations in Taiwan. In this study, a rock scour model is implemented into a one‐dimensional (1D) hydraulic and sediment transport model. The rock scour model has components to predict the potential scour due to direct flow hydraulic forces and scour due to sediment abrasion. The resultant 1D model is capable of simulating the combined effects of rock erosion and alluvial river erosion and deposition. The new model is applied to the Tachia River in the reach affected by the Chi‐Chi earthquake in 1999. Findings related to the applicability and limitations of the current rock scour models are reported.

Select this Article		Predicting Rock Scour in an Alluvial River with a Two‐Dimensional Model Yong G. Lai, Blair P. Greimann, and Kuowei Wu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)276 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Most rivers in Taiwan have a steep slope, subject to high flows, and have relatively weak bedrock. Bedrock is often exposed and rock scour is an important river process. For example, the river channel downstream of the Chi‐Chi Weir on the Choshui River experienced up to 10 meters of rock scour since the construction of the weir in 2001. The occurrence of deep rock scour has been a major threat to river infrastructure at many other locations in Taiwan. In this study, rock scour models are reviewed and a specific rock scour model is proposed. Among rock scour mechanisms, those due to flow hydraulic force and sediment abrasion are considered to be important. The rock scour model is incorporated into an existing two‐dimensional (2D) mobile bed model, SRH‐2D version 3. The resultant 2D model is capable of simulating the combined effects of rock erosion and alluvial river erosion and deposition. The new model is applied to the river reach at the Chi‐Chi Weir in an attempt to test and verify the applicability of the rock scour model. Findings related to the applicability and limitations of the current rock scour models are reported.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS I

Select this Article		3D Numerical Modeling of John Day Lock Tainter Valves E. Allen Hammack and Richard L. Stockstill ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)277 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The reverse tainter valves in the culverts at John Day Lock have been failing structurally for the life of the project. Recently, district engineers have decided to redesign these tainter valves to reduce or eliminate cracking and other structural issues. In order to complete this redesign, three‐dimensional (3D) simulations were conducted of the flows experienced through the culverts for several valve openings seen during a lock operation. These 3D simulations were performed with the 3D Navier‐Stokes module of the numerical code Adaptive Hydraulics (ADH) (http://adh.usace.army.mil/) developed by the U.S. Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (CHL). This code models the complex 3D flows around hydraulic structures using adaptive meshing techniques on unstructured meshes. The flow variables, pressure and velocity, calculated at each node lying on the surface of the valve were exported for use as boundary conditions for a 3D structural model of the tainter valve.

Select this Article		A Three‐Dimensional Numerical Model for Flow in a Lock Filling System Richard L. Stockstill, F. ASCE and R. Charlie Berger, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)278 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The hydraulic performance of a navigation lock is difficult to evaluate because the unsteady flow is characterized by large variations in pressure and velocity. The lock system contains the interactions of free‐surface and pressurized conduit flow. Currently, the filling and emptying system design must be carefully evaluated in a physical model which generally is expensive in terms of both time and money. A numerical model capable of simulating the flow in a navigation lock can provide an economical tool for detailed evaluation of lock systems and components. A flow model of a lock filling and emptying system must be capable of simulating the large‐ and small‐scale flow features found in internal (conduit) flow and free‐surface flow within the lock approach and chamber. This paper describes the development of a complete three‐dimensional (3‐D) model of a sidewall port lock filling system. The Reynolds Averaged Navier‐Stokes equations are used to describe the 3‐D flow. The equations are discretized using the Galerkin Least‐Squares finite element algorithm on tetrahedral elements with sizes varying over several orders of magnitude. The water‐surface location is determined using a moving mesh method. The code is parallelized using Message Passing Interface (MPI) and is capable of adapting the mesh during flow calculations based on error estimations.

Select this Article		Challenges on Three Dimensional Simulations of Free Surface Flow Jinwei Qiu and Xing Fang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)279 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Unsteady free‐surface flow in open channels with or without in‐channel structures are very complex. It is a difficult and challenging subject for civil engineering students to fully understand and comprehend. In this study three‐dimensional numerical simulations were performed for several case studies of open channel flows and used to demonstrate several aspects of educational challenges of computational hydraulics. FLOW‐3D, developed by the Flow Science, Inc., a three‐dimensional computational fluid dynamics (CFD) software was utilized as “Virtual Lab” to study these complex flow phenomena. FLOW‐3D utilizes a true volume of fluid (TruVOF) method to compute free surface motion and the fractional area/volume obstacle representation (FAVOR) technique to model complex geometric regions. In this study, flow simulations were presented on three case studies in various channel geometry and channel boundary conditions, and the cases include: the flow simulations of flow characteristics in the experimental channels having weirs with different heights in the middle of simulation domain; the flow simulations under complex channel bottom geometry from supercritical flow to subcritical flow with hydraulic jump due to tailwater effects in a laboratory channel; and the flow simulations of flow characteristics in a long river reach with a broad‐crested weir located at the middle of the reach. The simulations demonstrate to use basic hydraulic principles to set appropriate boundary conditions, and conduct model comparison and calibration against results from theoretical equations, other numerical models and laboratory measurements. The detailed analyses revealed flow features of the unsteady free‐surface flow in open channels under various boundary conditions. The impacts on water surface profile and flow velocities due to in‐channel hydraulic structures were discussed. The study demonstrates challenges of computational hydraulics in how students and researchers critically analyze three‐dimensional simulation results using basic one‐ and two‐dimensional hydraulic theories and principles.

Select this Article		Comparison of the Princeton Ocean Model and the Regional Ocean Modeling System Hindcasts in the Delaware River and Bay Richard A. Schmalz, Jr., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)280 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The National Oceanic and Atmospheric Administration is in the process of developing a nowcast/forecast system for Delaware River and Bay. The Delaware Bay Operational Forecast System (DBOFS) will extend from the head of tide at Trenton, NJ through the Bay entrance out onto the continental shelf and will supplement the Delaware Bay Physical Oceanographic Real Time System (PORTS), which was installed in 2003 to provide observed, real‐time water surface elevation, currents, temperature, salinity, and meteorological information. In conjunction with the DBOFS development effort, the Princeton Ocean Model (POM) and the Regional Ocean Modeling System (ROMS) have been applied with a common medium resolution grid in hindcast mode using common forcings to simulate two 15‐day periods in March (high river flow) and September (low river flow) 1984. Herein, we compare and contrast the hindcast simulation results versus the National Ocean Service Delaware River and Bay 1984 Circulation Survey measurements of water surface elevation, currents, salinity, and temperature. The effects of a spatially varying bottom friction, subtidal water level forcings at the Chesapeake and Delaware Canal boundary, navigation channel bathymetry, and upriver storage areas on water level, current, and salinity response are considered. In conclusion, plans for further DBOFS development with ROMS using a finer resolution grid are presented.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS II

Select this Article		A Process‐Based Unsteady Model for Wave‐Current‐Morphodynamic Changes in Two‐Dimensions S. N. Kuiry, Yan Ding, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)281 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A process‐based two‐dimensional model for simulating coastal wave, tide‐ and wave‐induced currents, and coastal morphodynamic change is presented. The integrated model includes three different submodels: (1) wave model, (2) wave‐induced current model and (3) sediment transport model. A phase‐averaged wave model based on linear wave theory is used to simulate wave transformation, deformation and to calculate radiation stresses. The current model is based on the solution of the conservative form of the nonlinear shallow water equations and effects of the Coriolis force, wind stress, bottom irregularities and short wave‐averaged radiation stresses are included. The forward Euler discretization is used for the unsteady term and the convective term is discretized using Godunov‐type shock capturing method on non‐uniform rectilinear grids. The hydrostatic flux is calculated using an equivalent water depth at each cell interface and the bed slope source term is treated in such a way that exact balance between hydrostatic flux and bed slope source terms is achieved under still water condition. The morphodynamic change is modeled by considering local sediment balance and anisotropic downstream gravitational effect. The three submodels are operated systematically and required parameter values are transferred to the respective submodels. This sequential computations are carried forward in a cyclic order till simulation time reaches to the end time. In order to test the applicability of the model, a severe storm attack on an ideal coast is simulated. The preliminary results show that the developed model can be applied to simulate wave‐current‐morphodynamic processes in coastal and estuarine zones.

Select this Article		Simulation of Multilayer Shallow Water Fluid Flow Using Lattice Boltzmann Modeling and High Performance Computing K. R. Tubbs and F. T. ‐C. Tsai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)282 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A lattice Boltzmann method (LBM) on high performance computing (HPC) environments for three‐dimensional shallow water flow fields is developed. Recently, the LBM has become an attractive numerical method to solve various fluid dynamics phenomena. However, LBM has not been extensively applied to shallow water equations. The shallow water equations have wide applications in ocean and hydraulic engineering which can benefit from the advantages of the LBM. The standard LBM for two dimensional shallow water flows is extended to three dimensional flows by solving the multilayer shallow water equations. LBM is an attractive method for solving the multilayered shallow water equations because the extension to a multilayer formulation is straight forward and all simplicities and advantages of the LBM are retained. The performance of the LBM for the multilayer shallow water equations is investigated and optimized in HPC environments. We numerically demonstrate the applicability of the LBM in three dimensional shallow water flows and the LBM performance using OpenMP.

Select this Article		Two Dimensional Hydraulic Modeling of the Lower Skokomish River Cassie Klumpp ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)283 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Bureau of Reclamation's Sedimentation and River Hydraulics Group SRH‐2D model was applied to the lower 10 miles of the Skokomish River, WA. This was in conjunction with a Geomorphic Study of the reach. The river is aggrading and is therefore limited in its ability to convey flood flows. The 2D model was used to identify channel capacity and areas within the reach where overbank flooding occurs. The model was applied to existing conditions in the reach, and may be used in the future for proposed changes to improve channel capacity.

Select this Article		Using Computational Model — ADH to Evaluate Relationship of Water Surface Elevation to Wing Dikes Renjie Xia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)284 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The use of hydraulic structures, such as wing dikes, to control flow, increase the channel capacity to carry sediment, and reduce periodic dredging requirements is an important management tool utilized on the Upper Mississippi River. Wing dikes concentrate flow in the navigation channel, control flow into secondary channels, and influence the location of channel erosion and sedimentation. This study modeled the lower portion of Pool 22 of the Mississippi River from river mile 301.2 to 304.2 using the ADaptive Hydraulics (ADH) Modeling System. Alternatives, including no dikes and dikes in the main channel, were compared to evaluate the relationship of water surface elevation to wing dikes for a range of flow conditions. This study showed that (1) construction of new wing dikes initially alters the water surface elevation, but the change is small; (2) for flow discharges less than 160,000 cfs, with decreasing the river flow, the change of water surface elevation due to wing dikes decreases; and (3) for flow discharges greater than 160,000 cfs, with increasing the river flow, the change of water surface elevation due to wing dikes decreases.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS III

Select this Article		ADH = Fast & Stable 2D Finite Element Model Thomas Gambucci ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)285 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract ADH (ADaptive Hydraulics) is the modern, multi‐dimensional hydraulic modeling program in development by the Coastal and Hydraulics Laboratory (CHL) of the Corps' Engineering and Research Development Center (ERDC). The model was publicly released in September 2007 but has been used by the Rock Island District (MVR) since January 2006. MVR and other Corps Districts have been successful using ADH for many 2D applications and have found the shallow‐water (2‐D) module of ADH to be very fast and stable compared to previously used 2D hydraulic programs (RMA2 and HiVel2D). As beta users of the software, MVR had the opportunity to provide feedback to ERDC to help shape the program towards user needs and has assisted in technology transfer to other Corps districts throughout the region by hosting training workshops. The Navigation and Ecosystem Restoration Program (NESP) is the implementation program for the recommendations contained within the Chief's Report for the Upper Mississippi River and Illinois Waterway System Navigation Study. This presentation will discuss the advantages of ADH and how it was used for the NESP Lock and Dam 22 project. A range of modeling applications were addressed, including: design of approach channel improvements, guardwall porting design for a newly proposed guardwall, design of a fish passage structure through the existing spillway, velocity field calculations during different stages of construction, and the overall effects of sedimentation due to the proposed work. Ongoing modeling activities are evaluating the effects of multiple projects constructed within a river reach to support objectives for both navigation and ecosystem restoration.

Select this Article		Evaluation of Methods to Reduce Backflows from the Chicago Waterway System to Lake Michigan Charles S. Melching, M. ASCE and Emre Alp ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)286 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A detailed study of seven historic backflow from the Chicago Waterway System (CWS) to Lake Michigan events (including the 2^nd and 4^th largest since 1965) was done to evaluate changes in waterway operation procedures to determine if backflows could be avoided or reduced in volume. The study applied a dynamic‐wave simulation model to the CWS at a 15‐minute time step combining measured inflows for the major tributaries, combined sewer overflow (CSO) pump stations, and water reclamation plants with simulated gravity CSO flows computed by the U.S. Army Corps of Engineers. The simulated CSO inflows were confirmed against a detailed mass balance approach for four storms and the peak flows from the two approaches were found to be remarkably similar. It was found that the hydraulic capacity limitations of the Chicago Sanitary and Ship Canal (CSSC) prevented changes in operations at the Lockport Powerhouse and Controlling Works from substantially reducing backflows. The maximum discharge through the CSSC is around 19,500 cfs whereas inflows may peak at 40,000 to 50,000 cfs and flows cannot drain away fast enough to avoid having to allow backflows to Lake Michigan. These backflows cannot be avoided until the reservoirs of the Tunnel and Reservoir Plan (TARP) are completed.

Select this Article		Modeling the Evolution of Incised Streams in Hammar Mesopotomian Marsh with Emphasis on the Contribution of Tidal Flow in the Filling Requirements A. H. Alkaabi, A. Ramamurthy, H. A. Al‐Thamiry, and A. A. Ali ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)287 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Tidal flow may contribute significantly in the amount of water to be considered in the restoration of wetlands, particularly when these wetlands were subjected to a drying process and there are shortages in the availability of water coming from highlands. The Mesopotamian marshes (The Iraqi Wetlands) are Al‐Hammar Marsh, Al‐Huwaiza Marsh, and Central Marshes (Al‐Qurna). These marshes were subjected during the last two decades to a drying process for mostly political reasons. The present study concerned with the Al‐Hammar Marshes.

Select this Article		Numerical Simulations of Coastal Floods and Morphological Changes Due to Sea Level Rise and Hazardous Storm Yan Ding, Moustafa Elgohry, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)288 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a simulation approach for assessment of the impacts of sea level rise (SLR) on an estuary under complex hydrological conditions such as storm wave, tide, river flood, and sediment transport from rivers to estuary and coast. An integrated coastal/estuarine processes model is used to simulate hydrodynamic and morphodynamic responses to several scenarios of SLR and hazardous storms. Numerical results indicate that this model enables to simulate coastal flooding/inundation, shoreline retreat, and morphological change and respond correctly the interactive impacts of SLR and storms; it is therefore applicable to coastal/estuarine water planning and management for the purpose of flood prevention and erosion protection against the global mean SLR and hazardous storms.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS IV

Select this Article		Comparison of HEC‐RAS and InfoWorks RS a Case Study in Grand Prairie, Texas Thomas W. Mountz and Josha Crowley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)289 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Hydrologic Engineering Center's River Analysis System (HEC‐RAS) is a one‐dimensional computer model intended to perform hydraulic calculations for a network of open channels. This model is widely available, free of cost and is the most commonly used hydraulic model in the United States. Most HEC‐RAS models are steady state. Unsteady flow analysis in HEC‐RAS differs in many ways from the traditional steady state analysis. The largest difference involves the ability to input a full hydrograph to analyze the response of the river system to flows (and tailwater conditions) that vary with time. This is a case study on Lower Mountain Creek in Grand Prairie, Texas. The study area is between Mountain Creek Lake and the confluence with the West Fork Trinity River. This area offers many challenges to a traditional HEC‐RAS analysis, including relatively flat channel slope, a wide floodplain with split flows through multiple bridge openings, and considerable shallow overbank flooding. A comparison of the results using Steady HEC‐RAS, Unsteady HEC‐RAS and InfoWorks RS (IWRS) will be presented. The comparison will include not only differences in computational results, but differences in model structure, input requirements, and methodology.

Select this Article		Diversion of S‐4 Basin Drainage from Lake Okeechobee: Hydraulic Modeling of Alternatives Using HEC‐RAS Stephanie C. Otis and Gene L. Foster ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)290 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract One of the goals of the current Everglades restoration effort is to reduce the delivery of stormwater runoff to Lake Okeechobee from the drainage basins located south of the lake. The S‐4 Basin is one of these drainage basins that has not yet been diverted. An analysis was performed to determine the feasibility of diverting S‐4 Basin drainage southward, away from Lake Okeechobee. Unsteady flow hydraulic models of the diversion alternatives were developed using the Corps of Engineers HEC‐RAS program. These models are relatively complex with the numerous canals, pump stations, gated culverts and other structures. This paper covers the project background, model setup and the challenges faced by the modelers as well as some of the results obtained through the modeling effort.

Select this Article		New Floodplain Delineation Capabilities in HEC‐RAS Cameron T. Ackerman, P.E., D.WRE, Mark R. Jensen, and Gary W. Brunner, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)291 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Hydrologic Engineering Center's River Analysis System (HEC‐RAS) is widely used for computing water surface elevations with results processed using GIS to determine inundation extent and flood depths. These floodplain boundary and flood depth results are used to establish flood insurance rate maps, analyze severe flood events, establish emergency action plans, estimate flood damage losses, and evaluate habitat restoration alternatives. New floodplain delineation tools in HEC‐RAS provide the capability to develop inundation maps utilizing water surface profile results and a model of the ground surface. This delineation capability allow the modeler to visualize the resulting floodplain directly within HEC‐RAS, providing a more efficient environment for hydraulic model refinement than processing results in GIS. The resulting floodplain boundary and flood depths may then be used in other modeling software to evaluate floodplain impacts.

Select this Article		Transitioning NWS Operational Hydraulics Models from FLDWAV to HEC‐RAS Fekadu Moreda, Angelica Gutierrez, Seann Reed, and Cecile Aschwanden ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)292 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The NOAA National Weather Service (NWS) Office of Hydrologic Development (OHD) is investigating two approaches to transition NWS operational hydraulic models from FLDWAV to HEC‐RAS: (1) transform existing FLDWAV and DWOPER models into HEC‐RAS and (2) modify and calibrate existing HEC‐RAS models created for a purpose other than real‐time forecasting. We evaluated these two approaches in the lower part of the Tar River, NC, and the lower Columbia River, OR. We also developed procedures and utility programs to assist with model conversions. The results are mixed. For the relatively simple Tar River, direct duplication of FLDWAV cross‐sections and Manning's roughness specifications within HEC‐RAS resulted in similar simulations. Also, a model built with more detailed cross‐sections but the same roughness parameters from FLDWAV model could produce comparable simulation with some simple Manning's n adjustments. For the lower Columbia, approximate duplication of geometry requires more Manning's n adjustments, but still offers a viable pathway toward model conversion. Further work on the lower Columbia model is needed to see whether more precise representation of storage areas will improve results.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS V

Select this Article		Numerical Simulation of Dissolved Oxygen Concentration in the Downstream of Three Gorges Dam Xiangju Cheng, Xuewei Chen, and Yongcan Chen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)293 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Strong colliding between the flow discharged from spillway and the water‐body in the stilling basin will produce a lot of air bubbles in the downstream of the Three Gorges Dam. Bubble mass transfer will be dominant and can cause total dissolved gas (TDG) supersaturation. Elevated TDG levels can have an adverse effect on aquatic organisms in the form of gas bubble trauma (GBT). TDG concentration is changed with distance from the spillway crest and depending on hydraulic and operating conditions. Dissolved oxygen (DO) transport model is developed in this paper and used to simulate the physical processes of gas transfer coupled with the air‐water two‐phase mixture flow model. Supersaturated DO concentration in the water‐body downstream along with distance is successfully calculated during spillage when the water level is 139m in the Three Gorges reservoir.

Select this Article		On a Two‐Dimensional Temperature Model: Development and Verification Yong G. Lai and David Mooney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)294 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Government regulators on many rivers have specified acceptable temperatures based upon habitat and biological criteria. These temperature thresholds impose constraints on reservoir operations and can limit water deliveries and power generation. Existing tools based on low‐order modeling simplify a river to a simple line with limited spatial distribution of inputs and poorly represent physics of the river processes. The limited spatial extents restrict the usefulness of low‐order modeling for such features as agricultural returns, gravel pits, groundwater upwelling, side channel activation, and streamside vegetation. It also imposes limitation on fish habitat assessment and reoperation outside the range of the calibration datasets. This study develops a two‐dimensional (2D) temperature module for an existing 2D hydraulic model, SRH‐2D version 2. The 2D model incorporates data with both lateral and longitudinal geographic extents rather than lumping results into a point‐to‐point or uni‐directional representation. The objective was to improve the representation of spatial features where low‐order models resort to empiricism for a lumped treatment. Better representation of processes leads to increased accuracy and higher confidence. The SRH‐2D temperature model utilizes meterological data as inputs (solar radiation, cloud cover, air temperature, dewpoint temperature and wind speed). Physical processes modeled include solar radiation, terrain and vegetation shade, atmospheric radiation, water back radiation, heat exchange between water and river bed, water surface evaporative and conductive losses. The model formulation, along with governing and process equations, is discussed first. The model is then tested and verified with simple cases having analytical solutions. The model is finally verified by applying to flows on the McKay Creek downstream of the McKay Dam.

Select this Article		Simulations of Aquaculture Dissolved Waste Transport and Mixing in Near‐Coastal Waters S. K. Venayagamoorthy, O. B. Fringer, J. R. Koseff, and R. L. Naylor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)295 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The present study focuses on understanding the transport and fate of dissolved waste from aquaculture pens in near‐coastal environments using the hydrodynamic code SUNTANS, which employs unstructured grids to compute flows at very high resolution. We perform simulations of the dissolved waste field and study the effects of different flow conditions (tides and currents) on the evolution of the waste plume. The fish pen causes partial blockage of the flow, leading to the deceleration of the approaching flow and the formation of a downstream wake. Results of the concentration field for an oscillatory flow condition superimposed on a mean current are presented and compared with the concentration resulting from a unidirectional flow field. The simulation results highlight the complex (and different) circulation patterns that occur around a submerged fish pen under oscillatory flow conditions and provide an understanding of the impact of aquaculture fish pens on coastal water quality.

Select this Article		The Importance of In‐Stream Hydraulics in River Water Quality Models: Lessons from the Blackstone River Jeffrey D. Walker, Paula Sturdevant Rees, and Thomas K. Walsh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)296 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water quality models of rivers often include three fundamental components: inflows and pollutant loads from point sources and watershed runoff, in‐stream hydraulics, and in‐stream water quality processes. In many cases, model development focuses mainly on the first and third components, while less attention is given to the in‐stream hydraulics. An existing hydrologic model was used as a basis to develop a water quality model of the Blackstone River. Although the original model was calibrated to daily streamflow records, the hydraulics of the model proved to underestimate the travel time of the river. Initial attempts to calibrate the water quality model were unsuccessful since many of the parameter values governing in‐stream processes were forced outside of acceptable ranges to compensate for the underestimated travel times. In order to develop a more robust water quality model, the mainstem of the river was resegmented into a greater number of reaches such that each reach represented a uniform hydraulic profile. The resegmented model resulted in a longer travel time more representative of the actual conditions of the river. Subsequent calibration of the water quality model yielded realistic parameters values, which were within an acceptable range and similar to those used for other rivers in the region. This work illustrates the importance of developing a good hydraulic, and not just hydrologic, representation of a river as the foundation for a water quality model.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS VI

Select this Article		Inundation Mapping Using Hydraulic Models and GIS: Case Studies of Steady and Unsteady Models on the Tar River, NC Cécile Aschwanden, Seann Reed, and Keren Cepero ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)297 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The National Weather Service (NWS) recently began providing static inundation maps at selected river forecast points through the Advanced Hydrologic Prediction Service (AHPS) web pages. Positive feedback has motivated efforts to expand the forecast mapping program. In order to expand this mapping program efficiently and effectively, we need a more objective basis for determining where static forecast mapping is acceptable and where real‐time, dynamic forecast mapping is required. With the current static forecast mapping approach, we do not have quantitative guidance specifying how far away from forecast points the maps are valid. This pre‐print describes a methodology to develop this type of guidance and better understand sources of forecast mapping uncertainty. For this pre‐print, we present limited results from an example case study on the Tar River, NC, comparing water surface profiles generated from steady and unsteady flow hydraulic models. Results that are more comprehensive will be presented at the conference.

Select this Article		Performance Evaluation of Articulated Contrete Matting (ACM) Spillway at Lake Odessa, Iowa Thomas Gambucci ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)298 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Use of Articulated Concrete Matting (ACM) for overflow spillways has great ability to resist high overflow velocities, yet use of ACM for this purpose is rare at the Corps of Engineers. This presentation draws attention to the importance of ACM spillway design to the HH&C community and how it performed at Lake Odessa, Iowa during the Flood of 2008. Many Environmental Management Projects are protected from flooding by perimeter levees. Typically these levees offer 10‐year or 25‐year protection and are frequently overtopped causing major damage to levees that can be very expensive to repair following each flood. Levee breaches may also produce adverse impacts on the ecosystems that they are intended to protect. The addition of spillways on perimeter levees can drastically reduce or eliminate overtopping damage to levees. From experience in the Rock Island District, head differences of less than one foot between the exterior and interior water levels will result in insignificant levee damage during overtopping events. A simple but effective spreadsheet technique was used to size the spillways according to this design assumption. The final spillway design made use of articulated concrete matting (ACM) to resist anticipated shear forces versus the more conventional techniques of riprap or concrete spillways. Construction of the spillway was completed in the winter of 2006 by the Corps of Engineers, making the Lake Odessa spillway the first substantial ACM spillway project by the Corps of Engineers. The flood of 2008 overtopped the ACM spillway twice allowing Rock Island District and Resource Agency personnel to monitor water levels. This paper evaluates the performance of the ACM spillway at Lake Odessa and presents lessons learned from the Flood of 2008.

Select this Article		The Development of a Neural‐Based Biomarker Forecasting Tool for Classifying Recreational Water Quality Srinivas Motamarri and Dominic L. Boccelli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)299 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This study will develop a computational framework capable of rapidly classifying microbial surface water quality for the protection of public health. Three classification tools will be developed using multivariate linear regression (MLR), artificial neural networks (ANN), and linear vector quantization (LVQ). The MLR and ANN approaches first quantify the microbial concentration followed by classification, while the LVQ approach directly classifies the water quality. The algorithms will be applied to microbial and hydrologic data associated with the Charles River Basin using antecedent rainfall over the previous 24 and 168‐hrs and lag‐1 fecal coliform concentrations as explanatory variables. Preliminary results with the MLR algorithm illustrate very good classification when the observed data is below the appropriate water quality standard (true negative rates > 95%). Unfortunately, the MLR classification approach does not perform as well when the observed data is greater than the standard (true positive rates ∼ 50%). Additional studies will be focused on evaluating the architecture and performance of both the ANN and LVQ approaches for classifying the microbial water quality, and the best performing algorithm identified.

Select this Article		Use of Hydraulic Modeling to Develop a Small Dam for the Geum River Reach in Sejong City Sangman Jeong, Christabel Jane Rubio, Joo‐Heon Lee, Leehyung Kim, and Kwangseob Shin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)300 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Currently, building a small dam located 1.16km downstream from Geumnam Bridge is being considered in order to improve the riverine scenery of the site for Sejong City and to create a hydrophilic space. The purpose of this research is to present the appropriate dimensions of a small dam by reviewing the flood control reliability of the Geum River after the small dam is built. To establish this purpose, changes in the flood water level were compared and analyzed by changing the installation height of a small dam using HEC‐RAS and FESWMS models. HEC‐RAS and FESWMS models were applied to perform the hydraulic analysis of the reach. The results showed that flood control reliability was guaranteed when the installation heights of the small dam were 7 meters and 5 meters using HEC‐RAS and FESWMS models respectively. From the FESWMS model, a more accurate result can be developed because the model could provide a two dimensional hydraulic analysis. The results can be used to determine the appropriate dimensions of a small dam for Sejong City.

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COMPUTATIONAL HYDRAULICS AND HYDRODYNAMICS VII

Select this Article		An Efficient Solution for Water Supply Networks S. Engin Mendi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)301 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In a computer implementation, a water network model is represented by a set of network data (values of parameters) and a set of equations (physical operation of the model). The fundamental model is formulated using the laws of physics. Subsequently, different models can be derived by mathematical manipulation. For water network models three physical laws are employed: flow continuity, head‐loss continuity and component equations (head/flow law). Industry and academia have made a significant investment in the research and development of computer algorithms for the design, modelling and control of water supply networks. The industrial use of many of these algorithms is commonplace and they are complex procedures used to solve systems of equations. Therefore, powerful numerical algorithms used to solve the model equations are crucial in terms of their computational complexity i.e. requirement of average number of iterations for finding a solution with a required accuracy. Along with physically simplified networks representing certain aspects of reality, neglecting other aspects with a smaller number of components than the original network, effective solution methods for water supply networks become common practice. To do this, first we must form a mathematical model representing the physical system; second, we need to set up an efficient solution implementation which is specific to the equation systems and finally we must visaliuze and post‐process the results.

Select this Article		Comparison of Mean Flow and Turbulence around Experimental Spur Dike Jennifer G. Duan and Li He ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)302 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract An acoustic Doppler velocimeter was used to measure flow and turbulence around an experimental spur dike in a flat and a scoured bed. Differences of mean velocity, turbulent intensity and Reynolds stresses between these two flow fields were compared and analyzed. Upon the formation of scour hole, mean flow velocities in the downstream and lateral directions were reduced, but increased in the vertical direction. The turbulence intensities (u’ and v’) are much larger, and the vertical component (w’) is smaller than that in the flat bed. Bed shear stresses determined from near‐bed Reynolds stresses in the scoured bed were smaller than that in the flat bed. These results indicated that local scour has not only significantly reduced bed shear but also contributed to the increase of turbulence intensities in the scouring zone.

Select this Article		Measuring Discharge with ADCPs: Inferences from Synthetic Velocity Profiles Chris R. Rehmann, David S. Mueller, and Kevin A. Oberg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)303 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Synthetic velocity profiles are used to determine guidelines for sampling discharge with acoustic Doppler current profilers (ADCPs). The analysis allows the effects of instrument characteristics, sampling parameters, and properties of the flow to be studied systematically. For mid‐section measurements, the averaging time required for a single profile measurement always exceeded the 40 s usually recommended for velocity measurements, and it increased with increasing sample interval and increasing time scale of the large eddies. Similarly, simulations of transect measurements show that discharge error decreases as the number of large eddies sampled increases. The simulations allow sampling criteria that account for the physics of the flow to be developed.

Select this Article		Statistical Analysis of Water Distribution Networks Design Using Harmony Search Daniel Mora, Pedro L. Iglesias, F. Javier Martinez, and Vicente S. Fuertes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)304 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The meta‐heuristic techniques are optimization methods that allow the search beyond local minimums, which extends in many occasions the search field, and therefore, the capacity to obtain good solutions. The Harmony Search (HS) is a heuristic technique of optimization used for water distribution networks design. Initially, the work displays the results of the HS on a water network studied in the literature (network of Hanoi). The results show the kindness of the method. Also is made a statistical analysis of the obtained solutions. This analysis allows verifying the values of the harmony parameters more suitable for the proposed method. The second part analyzes the influence of harmony parameters in the velocity of the algorithm. The aim is to find the most suitable configuration of the problem, so that good solutions are obtained in the less time.

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DAM OPERATION, MANAGEMENT, AND SAFETY I

Select this Article		Alternatives Study of Willwood Diversion Dam Siltation Removal in Wyoming, USA Hui‐Ming Shih, Chih Ted Yang, Patrick F. Horn, and Lynn C. Stutzman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)305 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Willwood Dam was built in 1924 as a diversion dam for irrigation. It is a run‐of‐the river reservoir located at a developing point bar in Wyoming, U.S.A. Based on current operating criteria, the release flow is restricted by an allowable turbidity increase of 10 Nephelometric Turbidity Units (NTU) from upstream to downstream of the dam. Currently, two of the three sluice gates have been clogged by siltation. These limited sluicing capacities have increased the sedimentation within the reservoir and the irrigation canal network. In this study, de‐siltation alternatives combining dredging, sluicing, and flushing were recommended to achieve the dam's operation goals and restrict sediment accumulation. Three operation curves and three dredging alternatives were used to evaluate sediment flushing/sluicing performances by using GSTARS 3.01 models. This study presents an efficiency analysis of the de‐siltation alternatives, the expected operation life, and recommendations for this dam rehabilitation project.

Select this Article		Managing Reservoir Discharge through Accurate Flow Measurement Bryan J. Heiner and Steven L. Barfuss ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)306 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Reservoirs store water for many important purposes in today's world, including culinary, irrigation, recreation, and flood control. In order to ensure that this valuable resource is wisely utilized, the discharge from reservoirs must be managed through accurate flow measurement. Unfortunately many reservoirs do not have measurement structures that allow flows to be monitored or accurately managed. It is not uncommon to have reservoir discharge set by historical arbitrary methods, such as opening a valve a certain number of turns on a certain day or keeping downstream river banks or channels at a certain elevation. While historical methods are better than nothing, consistent releases in these cases usually depend on constant reservoir head or stable stream beds.

Select this Article		Numerical Modeling of Flushing Process in Dez Dam Reservoir by HR Wallingford Method Ali Khosronejad, Afshin Ashrafzadeh, and Majid Vazifedoust ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)307 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Dez dam is one of the key dams in Iran. It is 203 m high with a reservoir of 2.3 BCM volume. This double arch dam has been constructed in a narrow gorge in 1962, southern west of Iran. It has three irrigation outlets at level of 222.7 m asl, two power intakes at elevation of 270 m asl. No bottom outlet have been designed and installed for Dez dam and consequently the sediment‐entering reservoir cannot be evacuated easily. Considering an annual 15.8 million cubic meter sediment inflow into the reservoir, the bed level is increasing about 1.2 meter per year and therefore it is very necessary to take an appropriate measure saving dam reservoir. One of existing method to save dam reservoir is to flush the sediment out through existing bottom outlets. In this study, the feasibility and efficiency of pressure and free flow sediment flushing techniques have been studied and some good points are presented. The results of present study shows that the flushing method cannot resolve the sedimentation problem of Dez dam and it must be applied jointly by other methods to save the reservoir from being decommissioned.

Select this Article		Simulation Study for Minimizing Diurnal Variation of Flow in a Hydroelectric Project to Reduce Downstream Impact Maya R. Ray and Arup Kr. Sarma ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)308 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Hydro‐Electric project are generally operated as peaking plant. This induces diurnal variation of flow in the downstreams of the dam even in a run‐of‐the‐river scheme. Lower Subansiri Hydel project, proposed on the Subansiri River of Assam, India, is one of the major Hydel projects of India. Reservoir Simulation Model has been developed with a prime objective to assess extent of flow variation in the downstream of the dam. The simulation study has revealed that during lean period the discharge in the downstrem increases significantly during the peaking hour and the flow discharge become almost zero during the non‐operating period. While the high discharge may cause erosion and can create flood like situation, the low discharge may have several adverse impact like increase in pollutant concentration. Scope of adopting structural and non‐structural measures for minimizing deviation of flow from its normal condition has been investigated and encouraging result has been found.

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DAM OPERATION, MANAGEMENT, AND SAFETY II

Select this Article		Optimal Design and Operation of Fuse‐Gates Considering Water Loss due to Gates Tilting Abbas Afshar and Zeinab Takbiri ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)309 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Installation of fuse‐gates on free spillways might be a safe and reasonably simple solution to increase reservoir capacity compared with the expensive alternative of dam heightening. This research aims at optimum design of fusegates considering the flood routing process in the reservoir. Owing to the fairly complicated performance of fusegates in flooding condition, its optimum tilting control is a challenging task. The overall expected cost which includes expected cost of water loss and gates replacement as well as the initial gates installation cost is considered as the objective function of the optimization problem. Moreover, an efficient mixed Genetic Algorithm model is utilized to minimize the overall cost. Type of gates, their height and first tilting head are explicitly treated as decision variables. A case example is used to assess the applicability of the proposed optimization scheme. The results indicate that consideration of flood routing could have a significant effect on the optimum design of gates.

Select this Article		The Effect of Step Height on Energy Dissipation in Stepped Spillways S. L. Hunt, Ph.D. and E.I.T and K. C. Kadavy, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)310 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A two‐dimensional, physical model was constructed to evaluate the energy dissipation on a 4(H):1(V) slope spillway chute. Step heights of 38 mm (1.5 inches) and 76 mm (3.0 inches) were evaluated, and energy losses created by these steps were compared. Model unit discharges ranging from 0.11 m³/(s⋅m) (1.2 cfs/ft) to 0.82 m³/(s⋅m( (8.9 cfs/ft) were tested. Water surfaces, bed surfaces, velocities, and void fractions in the flow were measured during the tests. The findings from this research show that a relationship developed by Hubert Chanson can be used to determine the inception point for slopes as flat as 4(H):1(V). With increasing step height, the energy losses at similar locations within the spillway chute also increased. The results for energy losses for the 38 mm (1.5 inches) and 76 mm (3.0 inches) steps showed similar linear trends upstream of the inception point, with near zero percent energy loss at the spillway crest to approximately 30% at the inception point. Downstream of the inception point for the two smaller step heights, the results showed a more logarithmic trend from 30% at the inception point or when a normalized length, L/L_i∗, equals one to 73% when L/L_i∗ equals 3.5. This research is expected to assist engineers with the design of stepped spillways applied on relatively flat embankment dams and the associated stilling basin located at the toe of the spillway.

Select this Article		The Geneva Dam, IL Hydraulic Roller Problem: Design of a Temporary Steep Riprap Ramp Yu‐Chun Su, Ph.D., P.E., CPESC, CPSWQ, CFM, Loren Wobig, P.E., CFM, Brad Winters, P.E., CFM, Xin He, Ph.D., and David T. Williams, Ph.D., P.E., D.WRE, F. ASCE, P.H., CPESC ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)311 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Run of the river low head dams provide an attractive nuisance since the relatively placid areas downstream of the dam entice people to either swim or canoe/raft/kayak into these areas. To address this public safety issue, the Illinois Department of Natural Resources, Office of Water Resources (IDNR) had been tasked to develop a hydraulic analysis or methodology to define the hydraulic characteristics at the Geneva Dam (on the Fox River near Geneva, IL) spillway and to develop the sizing of a temporary rock ramp on the downstream side of the existing run‐of‐river dam ogee spillway. The rock ramp was to minimize the existing submerged hydraulic jump “roller” at the site for flow conditions up to a 5‐year frequency flow event. The rock ramp would also be stable for up to a 100‐year frequency flow condition with a 20‐year expected project life until a more permanent solution is developed and implemented. A temporary rock ramp was proposed and sized to accomplish these criteria for the downstream side of the Geneva dam spillway. Several riprap methods that were applicable to steep slopes were analyzed. To facilitate the computations and to make direct comparisons of the results, a spreadsheet was developed that contained all of the methods and included warnings for applicability of the methods. This paper describes the thought processes, the applicability of single and multi‐dimensional computational models for addressing the hydraulic roller problem, and the computations and the development of the steep ramp riprap design spreadsheet.

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ECO‐HYDRAULICS

Select this Article		Fish Passage and Abundance around Grade Control Structures on Incised Streams J. T. Thomas, A. N. Papanicolaou, C. L. Pierce, D. C. Dermisis, M. E. Litvan, and C. J. Larson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)312 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes research from separate studies of fish passage over weirs (Larson et al., 2004; Litvan, 2006; Litvan, et al., 2008a–c) and weir hydraulics (Papanicolaou and Dermisis, 2006; Papanicolaou and Dermisis, in press). Channel incision in the deep loess region of western Iowa has caused decreased biodiversity because streams have high sediment loads, altered flow regimes, lost habitat, and lost lateral connectivity with their former floodplains. In‐stream grade control structures (GCS) are built to prevent further erosion, protect infrastructure, and reduce sediment loads. However, GCS can have a detrimental impact on fisheries abundance and migration, biodiversity, and longitudinal connectivity. Fish mark‐recapture studies were performed on stretches of streams with and without GCS. GCS with vertical or 1:4 (rise/run) downstream slopes did not allow fish migration, but GCS with slopes ≤ 1:15 did. GCS sites were characterized by greater proportions of pool habitat, maximum depths, fish biomass, slightly higher index of biotic integrity (IBI) scores, and greater macroinvertebrate abundance and diversity than non‐GCS sites. After modification of three GCS, IBI scores increased and fish species exhibiting truncated distributions before were found throughout the study area. Another study examined the hydraulic performance of GCS to facilitate unimpeded fish passage by determining the mean and turbulent flow characteristics in the vicinity of the GCS via detailed, non‐intrusive field tests. Mean flow depth (Y) and velocity (V) atop the GCS were critical for evaluating GCS performance. Turbulent flow measurements illustrated that certain GCS designs cause sudden constrictions which form eddies large enough to disorient fish. GCS with slopes ≤ 1:15 best met the minimum requirements to allow catfish passage of a flow depth of ≥ 0.31 m and a mean flow velocity of ≤ 1.22 m/s.

Select this Article		Fish Passage can be Improved by Introducing Hydraulic Refuge. Can the Effects be Quantified? Matthew D. Hays, Suzanne K. Monk, Trevor P. Hawkes, Joseph R. Webb, Rollin H. Hotchkiss, Mark Belk, and Russell Rader ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)313 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Design methods that account for the ability of fish to swim upstream through culverts are based on tests describing how fast and for how long different fish species can swim. These methods are based on an average water velocity but fail to recognize that fish can take advantage of resting places and non‐uniform flow in culverts. Culverts that are designed using this average velocity are likely larger than is necessary. Current design methods could be greatly improved by accounting for the non‐uniform velocity distributions in culverts, especially those with roughness elements. In order to better quantify the benefits associated with in‐culvert hydraulic refuge, fish tests have been performed in a laboratory flume. This project has focused on one species of fish native to Utah—longnose dace—and the ability to ascend the flume with and without roughness elements—cylinders—in place. Results suggest that the cylinders did allow fish to navigate upstream more successfully than fish attempting to ascend the flume without cylinders at nearly identical average velocities. It is suggested that further testing be conducted by adapting this protocol to key variables affecting fish passage, producing probability distributions for fish performance applicable to culvert design.

Select this Article		Hydraulic Model Study of Canoe Chute and Fish Passage for the Chicago River North Branch Dam Jorge D. Abad, Andy Waratuke, Cristiana Barnas, and Marcelo H. Garcia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)314 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The hydrodynamics at two design discharges (85 and 15% exceedence on the flow duration curve) in the vicinity of the existing North Branch Dam are presented. A combination boat chute/fish passage is being designed for integration into the existing dam. The Dutch pool and orifice fishway has been selected for the fishway due to its relatively low flow requirement (on the order of 5 cfs for most operating heads), low velocities in the fishway, and relatively low turbulence in the fishway — all making it a reasonable option for passage of non‐anadromous fish in a low‐gradient waterway. The details of the hydrodynamics of this structure are being examined with a combination of a physical model study and through the performance Computational Fluid Dynamic (CFD) modeling.

Select this Article		Some Findings on Effective Discharge Determination for Gravel Bed Rivers Carmen E. Bernedo, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)315 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The variability in the effective discharge (Qeff) calculations was assessed and attributed to the flow frequency distribution (FFD) determination, the type of sediment data used in the analysis and the methodology used in the calculation. Improvements to the existing methods for Qeff determination included the use of a Log‐Pearson Type III model to represent the FFD in an analytical approach and the use of density frequency distributions to avoid dependence on the class size of histograms, and to replace the concept of frequency of discrete events by frequencies of a continuous variable. A sensitivity analysis by using the analytical approach demonstrate that the use of the suspended sediment load data to infer the bedload transport rates is inappropriate and that FFD with less skew in the data tend to have low values of effective discharge. Qeff for three gravel rivers (i.e., SF Salmon, SF Payette and Boise Rivers) were calculated. Methods used yield to similar results. Effective discharge is reached or exceeded about 6, 17 and 7 days per year for the SF Salmon, SF Payette and Boise River, respectively. The values of effective discharge and bankfull discharge are nearly identical for Boise and Payette River and the effective discharge is 1.2 times the bankfull discharge for Salmon River. This paper will emphasize understanding the basis of the formula or methodology for correct application. Numerical results are presented in comparative tables as well as conclusions.

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ECO‐HYDRAULICS MODELING

Select this Article		Expanded Method for Filtering Submerged Objects in Echosounder Data Tim D. Osting ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)316 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Methods for filtering raw bathymetric field data are useful when developing multi‐dimensional hydraulic models for river instream flow studies. Raw field data characterizing a submerged surface may include spikes or irregularities arising from instrument issues (e.g., signal loss, bubbles) or from actual objects (e.g., large woody debris) resting on or above the channel bottom. Identification and filtering of large woody debris (LWD) in single‐beam echosounder data has been investigated by others and these concepts can be extended to other submerged objects. An improved application of a median filter approach is presented here that includes a method for varying the filter half‐length to account for changes in boat speed. With improvements to the identification method, typical raw datasets can be used to more effectively locate submerged objects according to size class. When developing a hydraulic model, locating filtered objects aids in identifying areas of bathymetric complexity and calibrating roughness coefficients.

Select this Article		Numerical Simulation of Chemical Spills Using CCHE2D Model and Chemical Property Database Xiaobo Chao, Tingting Zhu, Munther Hammouri, and Yafei Jia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)317 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Chemical spills in surface waters often occur in modern societies, which cause significant impact on water quality, eco‐environment and drinking water safety. In this paper, chemical spill contamination in water resources is studied by using a depth‐integrated computational model, CCHE2D, modified for predicting fate and transport processes of chemical contaminants in surface waters. The processes of volatilization, photolysis, hydrolysis, adsorption, desorption, degradation, etc. were included, and the interaction between sediment bed and water column were also considered. To simulate the fates and transport processes of chemicals using the developed chemical spill module, many parameters of the chemical materials are needed. A database was developed to provide information for involved chemical processes. Hypothetical chemical spill cases were simulated using the CCHE2D model and the developed chemical property database.

Select this Article		One‐Dimensional Modeling of Water Quality and Aquatic Ecosystems in Streams Podjanee Inthasaro, Weiming Wu, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)318 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract CCHE1D is a one‐dimensional channel network model developed at the National Center for Computational Hydroscience and Engineering, the University of Mississippi. Recently, the CCHE1D has been enhanced to simulate water quality and aquatic ecosystems in streams. The numerical model computes stream water temperature by considering heat fluxes across the water surface. The aquatic ecosystem model considers a simple food‐chain model of phytoplankton, Zooplankton and fish. It simulates the changing concentrations of biotic organisms and couples with water quality parameters by considering processes of photosynthesis, respiration, mortality, decomposition and nutrient cycling. The integrated CCHE1D water quality and ecosystem model has been tested in the Tualatin River, Oregon. It well predicts the water temperature, phytoplankton biomass, Zooplankton biomass and other water quality parameters along the simulation domain.

Select this Article		Use of Artificial Neural Networks for Habitat Unit Composition Modeling Jian‐Ping Suen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)319 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Understanding the fish assemblage composition and assessing habitat preferences is an important requirement for ecological engineering practices for river restoration. This study collects fish and habitat data in the Tsengwen River Basin and Kaoping River Basin to provide criteria for fish habitat restoration projects. Fish samples were collected used prepositioned areal electrofishing devices designed for repeated grid sampling. The electrofishing data were used to identify habitat preferences and develop fish community‐habitat models. A fuzzy rule‐based model was used to characterize habitat units as deep pool, deep riffle, shallow riffle, and shallow pool based on measured depth and current velocity. The artificial neural networks then is used to model the connection between the autecology matrix analysis values and surveyed habitat unit compositions. The utility of the model was furthered using historical fisheries data in addition to the data collected as part of the study. The fish community‐habitat model results provide a reference condition that can be used to guide stream restoration and ecological engineering decisions aimed at maintaining the natural ecological integrity and diversity of Taiwanese rivers.

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ECO‐HYDROLOGY

Select this Article		Considering River‐Scale Ecological Improvements within Flood Management Planning: The Lower Menomonee River Watercourse Status Report Michael Schwar and Tom Chapman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)320 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Between 2000 and 2012, nearly $180M in flood management and ecological improvements will be made in the lower seven miles of the Menomonee River and Underwood Creek in Milwaukee and Wauwatosa Wisconsin. When complete, these improvements will alter areas along at least one bank over nearly 70 percent of the river, resulting in more than 130 acres of riparian land conversion in that highly urban reach. These improvements were and will be undertaken by multiple parties for a variety of land development, flood management, and ecological restoration purposes. To identify opportunities for providing multiple benefits from planned projects, the Milwaukee Metropolitan Sewerage District (MMSD) developed the Lower Menomonee River Watercourse Status Report. This report characterized the existing hydrologic, physical and ecological conditions of the river and its riparian area as it passes through a highly urbanized corridor. It summarized improvements made in the last seven years and identified remaining ecological and flood management concerns to be addressed by future projects. Additional projects are currently in various states of planning, and there is interest among various stakeholders to develop these projects in ways that provide additional environmental benefits beyond their primary flood management objectives.

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ECO-HYDROLOGY

Select this Article		Developing Linkages between Biological Impairment and Stream Siltation: A Case Study in the Northern Great Plains Ecoregion John S. Schwartz, Ph.D., P.E., Andrew Simon, Ph.D., and Lauren Klimetz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)321 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Loss of biological integrity in streams due to excessive suspended sediment is a major cause of water quality impairment in the United States today. States monitor and assess streams for biotic integrity, and list streams as “impaired” according to §303(d) of the Clean Water Act for those that do not meet biological criteria. Biological criteria are set by states based on benthic macroinvertebrates or fish community metrics, developed as indices of biotic integrity (IBI) per Level IV ecoregions. In many cases, causes for biological impairment are not clear, and commonly states list causes as “siltation” and/or habitat alteration without strong evidence. A critical need exists to improve analytical tools to link loss of biological integrity with “siltation”, and to estimate total maximum daily loads (TMDLs) for these impaired streams. This study tested an idea using autecological fish data and USGS suspended sediment concentration (SSC) data to better link causes of biological impairment to SSC metrics. The study was located in Northern Great Plains Level III Ecoregion, in which 77 USGS gauging stations with flow and suspended sediment data were co-located with fish data from federal and state agencies. Autecological data was summarized by fish species found in this ecoregion, including attributes on mesohabitat preferences, water quality tolerance, trophic structure, and feeding, diet, and spawning behaviors. An autecological data matrix was created using the species autecological information and site fish presence/ absence data, forming a matrix that included, per site, the number of occurrences an autecological attribute occurred for fish species present. Ecological analysis found significant differences for several autecological attributes between stable and unstable channels. Fish located at unstable sites tended to: 1) prefer open-water mesohabitat, 2) be dominated by herbivores with algae diet, and 3) exhibit non-guarding spawning behavior. Use of fish autecological data and the protocols applied in this study were found useful to improve “strength of evidence” approaches to link biological impairment to excessive SSC.

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ECO‐HYDROLOGY

Select this Article		The Effect of Natural Hydrological Disturbances (Defined from HSPF Simulated Hydrographs) on Trout Populations in Ungaged Streams of the Great Smoky Mountain National Park Keil J. Neff, Joseph Parker, John Schwartz, Matt Kulp, Steve Moore, and Meijun Cai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)322 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Hydrological processes impact the functioning of ecosystems and influence fish population dynamics. In the Great Smoky Mountains National Park (GRSM), native brook trout (Salvelinus fontinalis) and rainbow trout (Oncorhynchus mykiss) populations have declined in some watersheds over the past two decades. Since 1986, 69 streams (369 sites) are routinely sampled by GRSM fisheries biologists, in which detailed data have been collected on fish condition (length, weight), abundance, year class strength, and biomass. To evaluate the impact of floods and droughts on trout, indicators of hydrologic alteration (IHA) were computed for 127 fish sampling sites between 1990 and 2007. The Hydrological Simulation Program — FORTRAN was used to model flows at each ungaged fish‐sampling stream site. Outlets were defined for each site, and flow was calculated for the period of record. The model was calibrated by adjusting parameters including storage, infiltration, runoff, and ground water for three elevation classes (low < 800 m ≤ medium < 1200 m ≤ high) to fit flow output from model with two USGS gaging stations and one NPS gaging station. The ecohydrologic regimes, characterized using the IHA method, were compared with trout abundance and biomass at each site. Results indicated the abundance of young‐of‐the‐year brook and rainbow trout significantly declined after extreme floods and droughts. In particular, low‐flows during droughts significantly reduced recruitment for both brook and rainbow trout, which is likely due to decreased spawning habitat. Brook trout populations in larger low‐elevation streams showed more stability compared to smaller headwater streams.

Select this Article		Upper Mississippi River Basin Envirohydrologic Observatory Jeremy Bril, J. V. Loperfido, Craig Just, and Nathan Young ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)323 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The University of Iowa's IIHR — Hydroscience & Engineering is creating an envirohydrologic observatory on Pool 16 of the Upper Mississippi River. Centered at the Lucille A. Carver Mississippi Riverside Environmental Research Station (LACMRERS), the observatory's sensor network will collect highly time resolved data to support modeling efforts for water quality and watershed process studies. Coupling sensor data with models will enable testing of existing hypotheses and will generate new hypotheses focused on water quality, nutrient, and sediment fluxes as they relate to food webs containing freshwater mussels and microbes. One hypothesis currently under investigation is that intense deposition of particulate organic matter from extreme flooding alters these food webs through physical and chemical means.

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HYDRAULIC STRUCTURE

Select this Article		A Comparison of Formed Suction Inlets for Flood Control Applications David Werth, Mark Allen, and Brent W. Nicholas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)324 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Formed suction inlets (FSI) are commonly used with large vertical pumps in flood control applications. The US Army Corps of Engineers Type 10 FSI is used extensively throughout the southeastern United States. However, variations of this inlet have been utilized with increasing frequency for a variety of reasons including cost, flexibility of use in existing intakes and smaller foot prints. Type 10 formed suction inlets have a proven record of success in a wide variety of approach flow conditions including high cross flow applications and with less than ideal vertical or horizontal transitions. Published guidelines and extensive field experience provide reliable design guidance for this type of inlet. While design guidance has been published on alternative inlets there is very little information or data available providing a direct comparison of effectiveness between a Type 10 with an alternative FSI. This paper presents the results of a physical model study which was conducted with the specific goal of comparing the Army Corps of Engineer Type 10 FSI with an alternative “shoe box” version. The model was used to identify surface vortex activity for both types of inlets as well as a comparison of flow straightening and vortex suppression abilities. A side by side comparison of the two different formed suction inlet designs is presented which is useful when evaluating various station and equipment alternatives in flood control applications.

Select this Article		Case Study: Impact of Varying Mitered Suction Elbows on Large Wastewater Pumps David Werth and Ted Stolinski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)325 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Mitered elbows are commonly used for suction inlets on large vertical raw waste water pumps. While information exists regarding the appropriate number of miters or maximum angles to prevent flow separation, little information is available in regards to the impacts on the approach flow conditions into the impeller when used in pump suction piping. Pump manufacturers commonly use mitered elbows in dry‐pit and occasionally in wet pit pump applications. Each manufacturer has a “typical” design with a specific number of miters that is used across a wide range of elbow sizes and turning radii. Experience has shown that in some applications, an insufficient miter design can lead to severe instability of the approach flow into the impeller. Limited design guidance is available to evaluate the impact of mitered elbow design for varying flow rates and suction sizes. The Hydraulic Institute Standard does not address mitered suction elbows mounted directly on a pump suction. This paper presents the results of a physical model study which was conducted to evaluate an existing raw wastewater pumps station housing five large (40,000 gpm) pumps. The existing station has exhibited a number of issues over the years and when a sixth pump was added, a model study was conducted to evaluate the approach flow conditions. Testing indicated that the mitered suction inlets were causing excessive flow separation and significant velocity variations at the pump inlet. Test results are presented which outline the impact of varying the miter design on pump inlet conditions.

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IN‐STREAM STRUCTURES FOR HABITAT RESTORATION

Select this Article		Culvert Retrofit and Fish Passage: An Update Joseph R. Webb and Rollin H. Hotchkiss ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)326 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Culverts throughout the country are approaching or are past their original design lives. These ‘baby boomer’ culverts will need to be repaired, rehabilitated, or replaced. Because entire culvert replacement is so expensive and intrusive, alternate measures to extend the culvert project life are growing increasingly popular. One such method is slip lining, where a ‘sleeve’ is installed within an existing culvert barrel and stabilized. Plastic pipe sleeves are very popular for slip lining primarily because the plastic material's lower Manning's roughness values allow for the culvert capacity to be maintained despite a reduction in culvert size. Unfortunately, the reduced friction within the barrel can create a barrier to fish passage due to increased water velocities. The increased velocities also cause greater outlet scour which can result in further obstacles to fish passage. These new fish barriers can greatly affect aquatic ecosystems by limiting the access that fish have to smaller tributaries used for spawning and rearing—access that is critical to the life‐cycles of many fish, including stream salmonid populations.

Select this Article		Field Evaluation of Engineered Large Woody Debris for Structure Performance and Habitat Value Kendra Russell and Elaina Holburn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)327 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Engineered large woody debris (LWD) structures are frequently used for habitat restoration and enhancement, bank protection and stabilization, and to alter flow within a channel. This paper discusses current LWD guidelines as well as ongoing field investigations on constructed LWD structures in the Middle Fork John Day River near John Day, OR. Low altitude balloon photogrammetry was completed for seventeen structures on the Middle Fork John Day to complete a stability and effectiveness assessment of the LWD structures. A habitat evaluation of the structures was also completed. The structures have experienced just over a 2‐year peak discharge since constructed and are still in place. Preliminary findings show that the structures are generally acting as intended by altering channel morphology through locally narrowing the channel, adding pools, forming bars, and providing cover for fish habitat. The next step for the field analysis is to look at the stability of each LWD structure and perform quantitative comparisons.

Select this Article		Numerical Analysis of the Performance of Rock Weirs: Effects of Structure Configuration on Local Hydraulics Christopher L. Holmquist‐Johnson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)328 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract River spanning rock structures are being constructed for water delivery as well as to enable fish passage at barriers and provide or improve the aquatic habitat for endangered fish species. Current design methods are based upon anecdotal information applicable to a narrow range of channel conditions. The complex flow patterns and performance of rock weirs is not well understood. Without accurate understanding of their hydraulics, designers cannot address the failure mechanisms of these structures. Flow characteristics such as jets, near bed velocities, recirculation, eddies, and plunging flow govern scour pool development. These detailed flow patterns can be replicated using a 3D numerical model. Numerical studies inexpensively simulate a large number of cases resulting in an increased range of applicability in order to develop design tools and predictive capability for analysis and design. The analysis and results of the numerical modeling, laboratory modeling, and field data provide a process‐based method for understanding how structure geometry affects flow characteristics, scour development, fish passage, water delivery, and overall structure stability. Results of the numerical modeling allow designers to utilize results of the analysis to determine the appropriate geometry for generating desirable flow parameters. The end product of this research will develop tools and guidelines for more robust structure design or retrofits based upon predictable engineering and hydraulic performance criteria.

Select this Article		Quantitative Evaluation of Rock Weir Field Performance David Varyu, Kendra Russell, and Elaina Holburn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)329 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract River spanning loose‐rock structures are used in channels for a variety of purposes ranging from grade control to habitat complexity. Despite the use of in‐channel rock weirs for a myriad of purposes, there is a lack of widely applicable guidelines for the design of the structures. Integration of field, laboratory, and numerical data sets will provide a scientific basis for predicting structure performance under various river conditions and for developing the most‐effective design criteria. Investigation of surveyed structures in the field identified several important relationships between structure parameters and the degree of failure. The most notable include the relationships with throat width, open angle of the structure, profile arm angle, and distance to next upstream or downstream rock structure. In general, structures with wider throats relative to the channel width failed less frequently than those with smaller throats. Structures characterized by wider open angles and greater arm slopes tended to fail more frequently than those with narrower open angles and milder slopes. Structures placed in close sequence tended to fail less frequently than those with wide distances between structures. Additional field data continues to be collected and their inclusion in the field data set will further refine observable trends between structure parameters and degree of failure. The quantitative analysis performed in this study must be coupled with the results from the laboratory and numerical modeling components to best understand the relationships between geometric variables of the structure and structure stability.

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LARGE RIVER HABITATS

Select this Article		A Digital Floc Camera for Nonintrusive Measurement of Floc Parameters Remya G. Kumar, Ariel Ruiz, and Kyle B. Strom ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)330 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper discusses the use of a digital camera setup developed for the in‐situ measurement of floc size distributions as a function of time in a turbulent field. The camera assembly consists of a CCD camera fitted with a 2X objective lens coupled with an LED spotlight and a strobe controller. The setup allows for the measurement of a wide spectrum of particle sizes, ranging in size from 5 micron to a few millimeters, in a single image. The system was tested for accuracy using suspensions of known particle sizes (Coulter Counter standard particles) and compared to. The camera system is then used to measure floc particle size distributions of kaolin clay in fresh and salt water suspensions.

Select this Article		Multi‐Criteria Assessment of Pallid Sturgeon Habitat Restoration for the Missouri River John Stansbury, Ph.D., P.E., M. ASCE, Jennifer Gitt, E.l., S. M. ASCE, and Istvan Bogardi, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)331 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The U.S. Army Corps of Engineers (USACE) in cooperation with other agencies such as the U.S. Fish and Wildlife Service is currently planning, designing, and constructing projects designed to restore habitat for the endangered pallid sturgeon (Scaphirhynchus Albus) and associated species in and along the Missouri River. Management and restoration of habitat is a complex process with many and often conflicting priorities, and habitat restoration success is difficult to measure, in part because there is often a significant lag time between the restoration activity and the biological response by the target species. This project develops a multi‐criteria assessment tool to help the USACE and cooperators assess the status and the progress of the habitat restoration efforts on the Missouri River. The multi‐criteria assessment method uses composite programming which assesses the overall condition of the habitat based on multiple indicators (e.g., water velocity, depth, substrate). Indicator values were determined at different locations and times, and weights were assigned to the indicators to represent their relative importance. The result obtained from the assessment is a river bend‐scale value that characterizes the overall quality and quantity of habitat at different points in time for that bend. Conversely, the method can be used to characterize conditions before and after a habitat restoration project or to compare the effectiveness of different habitat restoration methods on different bends within the river reach. The assessment method will also be used to identify data gaps and deficient habitat components that require further restoration.

Select this Article		River Bed Sediment Classification Using ADCP F. Douglas Shields, Jr. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)332 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Description of physical aquatic habitat often includes data describing distributions of water depth, velocity and bed material type. Water depth and velocity in streams deeper than about 1 m may be continuously mapped using an acoustic Doppler current profiler from a moving boat. Herein we examine the potential of using the echo signal strength from the bed as an indicator of bed material type. Mean signal strength from soft, muddy beds was consistently 10 to 20 dB lower than mean signal strength from noncohesive (gravel or sand) beds. Sand beds tended to have complex signatures with large variances.

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LARGE RIVER RESTORATION

Select this Article		Environmental Aspects of Dredging: What about Air Quality? Mark J. Anderson and Brian D. Barkdoll, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)333 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Dredging has historically been important for keeping the nation's waterways navigable, mining, and more recently for the removal of contaminants and restoring natural habitat. The placement of dredged material, re‐suspension of sediments, and contaminated dredged material could all result in adverse environmental impacts. These impacts have all been, and are being, studied extensively. What has not been investigated, however, are the air emissions resulting from dredging operations. The incorporation of air emissions into management decisions such as the selection of dredging technology is needed and would allow decisions based on environmental impacts and not solely on cost. This analysis lends itself to a limited life cycle and ecoefficiency analysis.

Select this Article		Integrating Fluvial Geomorphology and Two‐Dimensional Hydraulic and Sediment Transport Modeling to Support Sustainable Design of Large River and Floodplain Improvements: The Trinity River Corridor Project, Dallas, Texas, USA Mark R. Tompkins, P.E., Ph.D., Greg Ajemian, P.E., Gregory Welch, P.E., Anthony Falzone, Kyle Winslow, P.E., Ph.D., Paul Frank, P.E., Beatriz Dongell, and Denny Mengel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)334 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Trinity River Corridor Project in Dallas, Texas will realign and naturalize eight miles of the Trinity River channel and create a wide variety of recreational and habitat features on the floodplain within the boundaries of the Dallas floodway. Major flood control projects in the 1920s and 1950s relocated, straightened, and channelized the river, and regular mowing on the floodplain has maintained homogenous conditions with limited habitat value. Primary river naturalization elements of the project include restoration of channel meanders, creation of more natural channel geometry, integration of natural geologic controls into the channel profile, and creation of an oxbow lake. Floodplain improvements include creation of wetlands, lakes, recreational features such as trails and playing fields, and establishment of more natural vegetation assemblages. This suite of channel and floodplain improvements will create more complex hydraulics and sediment transport characteristics that will strongly influence the operation and maintenance of the Project area, and therefore the overall sustainability of the Project. Therefore, the design of channel and floodplain features has been guided by detailed analysis of historical geomorphology of the Project site and the region, and two‐dimensional hydraulic and sediment transport modeling of the proposed channel and floodplain design. We present results from the integrated fluvial geomorphology and two‐dimensional hydraulic and sediment transport modeling based design process introduced in Tompkins et al (2008) and describe how these results, which included velocity and shear stress distribution and sediment deposition patterns, were used to develop and refine channel alignment, geometry, and bank treatment designs as well as configuration and design of floodplain features.

Select this Article		Rehabilitation of the Middle Rio Grande near Bernalillo, New Mexico Drew C. Baird and Carolyn Donnelly ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)335 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Along the Middle Rio Grande near Bernalillo, New Mexico, sediment loads and flood peaks have been reduced, and the river channel is incising and has converted from a low flow braided sand‐bedded channel to a single thread gravel‐controlled bed channel (often bi‐modal sediment transport conditions), with a slightly sinuous planform. As a result, the river has migrated laterally, and before the project, was closer to the levee that provides flood protection for the adjacent developed areas. A project has been implemented to prevent levee failure, safely pass peak flows, re‐establish some measure of floodplain connectivity, and improve habitat conditions for two endangered species. Project features include a new channel relocated away from the levee, bendway weirs, a low floodplain surface along the outside of the new river bend, a secondary channel, rootwads, and native vegetation plantings. The new low floodplain surface is intended to provide a new riparian zone near the existing riparian zone that has become decadent as a result of channel incision and reduced flood peaks. Data include post project cross sections showing the re‐connected floodplain and the initial riparian zone re‐establishment, and main channel and near bank vertical velocity profiles. Initial channel response is qualitatively evaluated.

Select this Article		USACE River Ecosystem Restoration Planning: Lessons Learned from the Illinois River Study Michael Schwar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)336 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Planning undertaken by the U.S. Army Corps of Engineers for the Illinois River (IL) Basin Restoration Study utilized formulation techniques that could be adapted for other river ecosystem restoration planning efforts. The USACE planning process requires quantification of benefits in order to evaluate the relative merit of alternative approaches. Historically, these benefits have often been quantified in terms of “acres of habitat created or improved”. However, when altered abiotic processes or biotic interactions limit ecosystem function to a larger degree than habitat limitation it is necessary to incorporate both spatial and functional considerations to develop meaningful measures of restoration benefit. In the Illinois River system, ecosystem function is generally considered to be limited by a combination of abiotic processes (including sediment transport, water level and water quality), biotic interactions (including lost connectivity and exotic species), and habitat limitation (including deep waters, connected backwaters and floodplains). for the Illinois River Basin Restoration study, developed by the USACE in partnership with the State of Illinois seven overall restoration goals were developed, each addressing one of the identified limiting factors. Each objective was quantified using individually specific criteria, such as tons of sediment delivered to the river, degree of water level fluctuation, miles of connected tributary mainstem and acres of connected backwater multiplied by a depth distribution function. Alternatives were then developed based on differential attainment of the various criteria relative to the level necessary to reach full functionality.

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MODELING DAM BREACH

Select this Article		A Depth‐Averaged 2‐D Model of Non‐Cohesive Dam/Levee Breach Processes Weiming Wu, Zhiguo He, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)337 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A depth‐averaged 2‐D model has been developed to simulate the breach processes of non‐cohesive dams and levees caused by overtopping flows. It solves the 2‐D flow and sediment transport equations using an explicit finite volume method on a rectangular grid, with the HLL approximate Riemann solver to handle the mixed‐regime flows near the breach. It considers interactions among transient flow, strong sediment transport and rapid bed change by including bed change and variable flow density in the continuity and momentum equations of flow. The model adopts the non‐equilibrium approach for total‐load sediment transport, and specifies different repose angles for the sediments below and above the water surface when handling the non‐cohesive embankment slope avalanching. It uses a varying time step length that satisfies both the CFL condition and the limitation that the bed change is less than about ten percent of the local flow depth at each time step. The test using laboratory experiments shows the developed model predicts well the breach dimensions and flow characteristics.

Select this Article		A Lattice Boltzmann Model for Dam Break Flows H. Liu, J. G. Zhou, R. Burrows, and Y. Peng ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)338 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A two‐dimensional lattice Boltzmann model (LBM) for dam break flows is developed. Shallow water equations coupled with the large eddy simulation model is numerically simulated by the lattice Boltzmann method, so that the turbulence can be taken into account and modeled efficiently. The model is verified and applied to two cases: (a) partial dam break flow; (b) circular dam break flow. The objectives of this study are to validate the two‐dimensional LBM in transient flow simulation and analyze the detailed transient processes in open channel flows.

Select this Article		Comparison of Dam Breach Parameter Estimators D. Michael Gee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)339 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Analytical techniques for the estimation of dam breach parameters were evaluated and compared. The development of potential flooding from a dam failure requires several elements; the hydrologic scenario, the possible dam failure modes, breach parameters that are associated with the failure modes, and the routing and mapping of the consequent discharge hydrograph. This paper presents recent research into the use and application of several dam breach parameter estimators to describe the physical characteristics of a dam breach, use of those parameters within the unsteady flow routing model HEC‐RAS, and the computation and display of the resulting downstream impacts. The breach parameter estimators that were used include both empirical and embankment erosion process models.

Select this Article		Representation of Linear Terrain Features in a 2D Flood Model with Regular Cartesian Mesh Mustafa Altinakar, Marcus McGrath, Yavuz Ozeren, and Edie Miglio ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)340 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Highly transient floods resulting from the failure of dams and levees can lead to loss of life and property damage. Two‐dimensional (2D) numerical simulations that use modern shock‐capturing schemes are particularly suited to simulate these mixed‐regime floods for flood mapping, consequence analysis and emergency management planning. The Digital Elevation Models (DEM) are often used as a regular computational mesh. Unfortunately, linear terrain features, such as road and railroad embankments and dikes, which may influence flood patterns, are not adequately captured in DEMs. This study describes a two‐sided cut‐cell boundary method for representing linear terrain features on a regular Cartesian mesh. The proposed method is briefly described and some test simulations are presented.

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RISK UNCERTAINTY

Select this Article		Flood Risk Assessment of Complex Riverine Systems Christopher N. Dunn, P.E. and Michael K. Deering, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)341 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract For over two decades, the U.S. Army Corps of Engineers (USACE) has required that all of their planning processes address the Nation's water resources needs in a systems context. Corps policy also requires that all flood damage reduction studies adopt risk analysis. While the USACE has these requirements, there is little guidance and few tools to support them. For this reason, the USACE Institute for Water Resources (IWR) sponsored investigations into the development of a new tool to analyze complex riverine systems while implementing the current flood risk analysis and systems requirements. This new tool, currently called HEC‐FRM or Flood Risk Management, is the next generation of the Hydrologic Engineering Center's Flood Damage Analysis (HEC‐FDA) model. This paper will present the model development for this tool which will be used for levee certification and assessment, planning and design studies, and advance the Corps modeling approach for risk analysis.

Select this Article		Optimal Design of Water Diversion System: A Case Study Mohammad Karamouz, Siyamak Doroudi, Azadeh Ahmadi, and Ali Moridi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)342 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Study of uncertainties in the design of dam diversion is of great importance due to its high economic impact on the construction cost. It is important to study the carrying capacity of the diversion systems, considering the hydrologic uncertainties due to climate change phenomenon and its impacts in decision making. In order to consider these uncertainties, the historical rainfall data of the nearest gauge stations have been analyzed, then the rainfall variations in the future have been predicted using down‐scaling of the GCM (general circulation model) data. The runoff of the basin is simulated using rainfall runoff modeling. The results of uncertainties evaluation have been incorporated in an optimization model. In this paper, a GA‐based optimization model for determining the optimal sizing of a dam diversion system is developed. The proposed model minimizes the flood damages and costs based on the optimal size of the dam diversion system in a probabilistic framework. The proposed algorithm considers risk in the decision making about diversion dam height and diversion tunnel characteristics. In this model, the hydrological uncertainties and the climate change impacts in design of dam diversion system are considered in the objective function of the optimization model. The proposed methodology is applied to the Karoun‐4 Dam in the south‐western part of Iran. The results show the significance value of considering flood risk and climate change impact on the design of dam diversion systems.

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RIVER STABILIZATION

Select this Article		Kansas River Bank Stabilization and Post‐Project Conditions John Blancett, P.E., M. ASCE and Pete Jarchow, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)343 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In addition to the original design and construction information from the 2003 EWRI publication, this paper also includes follow‐up regarding the Kansas River bank stabilization project condition. The Kansas River is a major Missouri River tributary. The project site is 43 miles (70 kilometers) upstream from their confluence, with a drainage area of 58,610 square miles (151,800 square kilometers). The channel ranges from 590 to 1180 feet (180 to 360 meters) wide in an 8860‐foot (2,700‐meter) floodplain. The project area was a channel bulge along the left bank of the river, at an inflection point where the channel meanders from the north (left) side of the floodplain to the south side of the floodplain. A bridge is located downstream, in the middle of an east‐west reach; downstream of the bridge, another meander returns the channel to the north. The sandy channel banks ranged from 20 to 30 feet (6 to 9 meters) tall, stood at slopes from 1.0 horizontal to 1.0 vertical, to nearly vertical, and tended to collapse into the channel thalweg and washed away whenever water levels receded.

Select this Article		Adverse Affects of Flood Flow at Skewed Railroad Crossings William Yord, A.M., Jerry R. Richardson, M., D.WRE, and Vincent J. Zink, S.M. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)344 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This poster presents a case study documenting the hydraulic issues relating to skewed bridge crossings. Although Hydraulic Engineering Circular Number 20 (HEC‐20) discusses these adverse affects, the illustrations and discussions of the issues relating to skewed bridges are brief. This is not a failing of HEC‐20 but an acknowledgement that, given the extensive scope of the subject matter contained in HEC‐20, this document can only provide a very broad treatment of the methods and process for evaluating and designing bridges in a variable morphological environment. This study presents the hydrologic investigation of a flood event from historic, eye witness, and post flood investigation. Analysis of this data clearly indicates that due to embankment skew, the water levels on the approach embankment were as much as 1.5 m (5 ft) higher than at the bridge opening. The consequences of this are graphically illustrated by photos taken during the flood, and analysis of post‐flood hydrographic survey data.

Select this Article		Physical Modeling of River Spanning Rock Structures: Evaluating Interstitial Flow, Local Hydraulics, Downstream Scour Development, and Structure Stability Kent L. Collins, Christopher I. Thornton, Brent Mefford, and Christopher L. Holmquist‐Johnson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)345 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Rock weir and ramp structures uniquely serve a necessary role in river management: to meet water deliveries in an ecologically sound manner. Uses include functioning as low head diversion dams, permitting fish passage, creating habitat diversity, and stabilizing stream banks and profiles. Existing information on design and performance of in‐stream rock structures does not provide the guidance necessary to implement repeatable and sustainable construction and retrofit techniques. As widespread use of rock structures increases, the need for reliable design methods with a broad range of applicability at individual sites grows as well. Rigorous laboratory testing programs were implemented at the U.S. Bureau of Reclamation (Reclamation) and at Colorado State University (CSU) as part of a multifaceted research project focused on expanding the current knowledge base and developing design methods to improve the success rate of river spanning rock structures in meeting project goals. Physical modeling at Reclamation is being used to measure, predict, and reduce interstitial flow through rock ramps. CSU is using physical testing to quantify and predict scour development downstream of rock weirs and its impact on the stability of rock structures.

Select this Article		Redesign and Rehabilitation of Railroad Bridges with Advanced Adverse Lateral Migration William Yord, A.M., Jerry R. Richardson, M., D.WRE, and Vincent J. Zink, S.M. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)346 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Much of the railroad infrastructure in the United States was initially built over a century ago, whereas the highway infrastructure is roughly half as old. Consequently, the existing railroad infrastructure presents more cases with advanced stream stability issues. These include advanced lateral and vertical migration which must be addressed when assessing, mitigating, or redesigning railroad bridges for stream stability and scour. Bridge 433.3 on the Union Pacific Railroad near Chickasha, Oklahoma is used as a case study to illustrate the problems with redesigning a railroad bridge crossing which has experienced advanced long‐term lateral stability issues, and to demonstrate how mitigating for stream stability and scour at railroads differs from similar work within the National Highway System.

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SEDIMENT TRANSPORT MODELING I

Select this Article		A Direct Method for Determining Riprap Size for Erosion Protection in Rivers Yongliang Jin and Brian D. Barkdoll, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)347 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In cases where an open channel needs bed and bank protection riprap is a common lining material, of which riprap size is the main design parameter needing determination. The current solution procedure is a cumbersome iterative one. A direct solution (one not needing iteration) is proposed here that improves computation time by 98% and adds less than 8% error.

Select this Article		Modeling of Sediment Particle Deposition and Resuspension Processes Using a Stochastic Jump Diffusion Particle Tracking Model Jungsun Oh and Christina W. Tsai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)348 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Although river beds generally tend to reach an asymptotic equilibrium, it may be abruptly altered by occurrences of natural extreme flow events or establishment of man‐made structures. These causes lead to significant morphological changes in the bed profile through erosion and deposition processes. The change of river bed can be quantified for predicting the stability of a river channel. The status of a geomorphological equilibrium can be determined by two transport phases, i.e., water and sediment transport. In particular, the bed profile in sediment transport models can be employed as the initial condition, and the calculated movement of sediment can set a new bed profile. Herein, we propose to use the stochastic jump diffusion particle tracking model (SJD‐PTM) to simulate the movement of sediment and particle deposition and resuspension processes. The stochastic diffusion jump particle tracking model is a Lagrangian particle tracking model governed by stochastic equations. When simulating the particle trajectories from the mean drift, settling velocity, diffusivity and extreme events, we can calculate the probabilities of deposition/scouring of a sediment particle by comparing the particle shear stress with the critical shear stress. As the result, we can trace particles and obtain particle trajectories and their statistical characteristics such as the ensemble mean and variance. Furthermore, we will be able to simulate particle deposition and resuspension processes.

Select this Article		Numerical Model of Channel Meandering in the Middle Sacramento River Jianchun Huang, Ph.D., P.E., David R. Varyu, M.S., and Blair P. Greimann, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)349 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract SRH‐Meander was used to predict the channel migration in the Middle Sacramento River. SRH‐Meander is a model developed in the Technical Service Center, Bureau of Reclamation to simulate the bed topography, flow field, and bank erosion rate in a curved channel with an erodible bed. The study area extends 101 miles from Red Bluff (RM 243) to Colusa (RM 142). The model was first calibrated by comparing the simulated channel alignment to the actual channel alignments for the period from 1976 to 1999. The erosion coefficients and the cutoff ratio were adjusted during the calibration. The calibrated model was used to predict the channel alignment in 2019 starting from the channel alignment in 1999. The terrain elevation was updated by tracking the erosion or deposition in the channel and by exchanging information between the 1D channel and 2D terrain.

Select this Article		One‐ and Two‐Dimensional Modeling of Deep Gravel Mining in the Rio Salado Dong Chen and Mingfa Liu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)350 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Impact of deep sand and gravel mining pits (with a depth of 10 meters) on flood zone coverage and riverbed change of the Rio Salado, Salt River, Phoenix, Arizona were simulated using one‐ and two‐dimensional numerical models. Two commonly used models are applied in the study, i.e., HEC‐RAS and CCHE2D. HEC‐RAS is a one‐dimensional hydrodynamic and sediment transport model developed by the U.S. Army Corps of Engineers, while CCHE2D is a depth‐averaged two‐dimensional hydrodynamic and sediment transport model developed at the University of Mississippi. The bed material was treated as three layers on the channel bed with multiple grain‐sized sediment mixtures. Changes in bed elevation were calculated by solving the sediment mass conservation equation. The modeling results of CCHE2D were compared with the HEC‐RAS modeling results and field observations, which showed that the 2D model was more robust in simulating flood zone coverage, non‐uniform sediment sorting, and channel geomorphologic changes.

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SEDIMENT TRANSPORT MODELING II

Select this Article		Effects of Gas Ebullition on Cohesive Sediment Resuspension and Cap Stability Pinar Cakir Kavcar and Steven J. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)351 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sediment resuspension can significantly contribute to the mass transport of sediment‐bound contaminants into the overlying water column. This study considers the influence of gas ebullition (due to microbial activity) on resuspension rates as observations indicate that fine‐grained sediments may be lifted into the water column in the bubble wakes. Capping aims to minimize contaminant migration to the water column by reducing sediment resuspension rates. In addition to the influence of gas fluxes on resuspension rates for uncapped cohesive sediment beds, this experimental investigation considers the effectiveness of two types of caps, sand and AquaBlok®. The investigation involved experiments conducted on sediments (d₅₀ = 10 μm) collected from the Anacostia River in Washington DC. Gas ebullition fluxes were selected based on values reported in the literature. The experimental results for the zero gas flux case indicated that the resuspension increases as the square of the bed shear stress level above a threshold or critical shear stress required to initiate resuspension. With regards to the ebullition experiments, it was observed that air migration occurs as a series of discrete bubbling events through semi‐permanent channels in the sediment bed associated with a cyclical buildup and release of gas pressure within the sediment. A significant amount of sediment was carried in the wakes of released bubbles. When the same conditions were studied with sediment caps applied over the bed surface, no sediment resuspension was observed over the duration of the experiments with the sand cap. AquaBlok® cap heaved up and ruptured if the pressure head differential across the cap reached a level on the order of 20–25 cm.

Select this Article		Empirical Equation for Abrasion of Stilling Basin Caused by Impact of Sediment M. E. Banihabib and M. Elahi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)352 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This research studies empirical equation for abrasion of stilling basin caused by impact of the sediment. Review of previous papers shows that in previous researches, the mixture effects of erosion and impact are studied without determination of the share of impact in the mixture effect. Also in those researches, the sediment grain size is not as large as debris size in debris flow or experiments are done without tail water depth. Therefore, in this research, the impact of large grain size is determined on concrete stilling basin with tail water. One dimensional analysis is carried out. The experiment includes concrete samples with three different cement contents, five depth of tail water, three grain sizes. Abrasion of each grain impact is measured and recorded. Uni‐variable and multivariable regression analysis was employed to possible relation between abrasion ratio and the dimensionless parameter of the experiment. The empirical equations are judged using mean relative error of the equations. Later a multivariable power equation is proposed for abrasion determination of the sediment impacts. The equation shows the abrasion is a function of dimensionless energy of sediment grain and the ratio of the grain velocity on stilling basin to the grain velocity on water surface. The results of the present research are used in estimating the longevity of Diversion Dams and concrete check dams in contact with debris flood.

Select this Article		Investigation of Land‐Use Change and Hydrologic Forcing upon Streambank Erosion and In‐Stream Sediment Processes Using a Watershed Model and Sediment Tracers J. P. Russo, J. F. Fox, and D. Martin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)353 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In stream erosion represents a significant portion of the watershed sediment budget for lowland watersheds, but current modeling strategies do not often include accurate methods for estimating the yield from stream bank sources or accurate representation of the stream bank erosion process at the watershed scale. This research presents a method for estimating the yield from stream bank sources using sediment carbon and nitrogen isotopic tracer results coupled with a watershed scale erosion and sediment transport model. The coupled fingerprinting‐watershed modeling framework is presented in the following steps: 1) measure the sediment yield from the study watershed; 2) estimate fraction of sediment yield eroding from stream banks using sediment fingerprinting data and use this and other collected data for the watershed model calibration and verification; 3) create a conceptually simple, yet representative, model of bank erosion processes and integrate the subroutine into the watershed erosion and sediment transport model, calibrate, and verify. Land use and climate change sceneries will then be used with the calibrated model to predict the effect on the sediment transport budget.

Select this Article		Retrofitting Stormwater BMPs in a Supercritical Flow Regime: A Hydraulic Perspective I. J. Tye, CH2M HILL MIE Aust, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)354 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A computational hydraulic model toolkit was required to facilitate designs that would permit retrofitting stormwater Best Management Practices (BMPs) and flow diversion structures on covered and open channels. This paper outlines the development of the computational hydraulic model toolkit. The paper addresses: 1). The computational hydraulic modeling of the base case — pre installation of the BMP, 2). The use of a Diversion Channel to divert the treatable flow from the Main Channel to the BMP via a weir or gate, 3). The transitioning of the flow regime from supercritical to subcritical immediately upstream of the BMP and wholly within the Inlet Diversion Channel to optimize the settlement of sediments in the BMP and limit sediment drop out in the Inlet Diversion Channel, 4). The transitioning of the flow regime from subcritical to supercritical immediately downstream of the BMP and wholly within the Outlet Diversion Channel to minimize flow depths, 5). The strategic positioning of the hydraulic jump outside of the Main Channel to prevent overtopping and the likely flooding of adjacent residences, 6). The design of flood mitigation works and the mitigation of sediment drop out upstream of the weir in the Main Channel, and 7). Retaining Main Channel capacity.

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SEDIMENTATION I

Select this Article		Numerical Simulation of Sediment Transport and Morphological Change of JiJi Weir Reservoir Yaoxin Zhang, Yafei Jia, Keh‐Chia Yeh, Chung‐Ta Liao, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)355 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract JiJi Weir was built across a mountain river, Chuoshui Creek, Taiwan. Because of deep slope, abundant sediment supply and tropical Typhoon climate, channel changes are very fast and occur in Typhoon seasons. Since its normal operation in 2002, the shallow reservoir of the JiJi Weir had a serious sediment problem: it could be filled up in just one strong typhoon event. Sediment will be completely carried through the reservoir and the spillway of the Weir. In this paper, a computational model, CCHE2D, was used to simulate the sediment transport of the JiJi Weir Reservoir. Transport of both suspended load and bedload sediments with multiple grain‐sizes was simulated, and the geomorphology changes were studied within the reservoir during nine typhoon events. Simulation results were compared with the measurements of morphological change, and it shows that the CCHE2D model is capable of producing reasonable and realistic morphological changes.

Select this Article		One‐Dimensional Modeling of Sedimentation Processes on the Puyallup River Brian G. Wardman, P.E., Brad R. Hall, P.E., and Casey M. Kramer, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)356 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the results of a sedimentation study using the one‐dimensional sediment transport capabilities of HEC‐RAS 4.0 to quantify sedimentation processes in the lower Puyallup River, WA. The HEC‐RAS 4.0 model used in this study was calibrated using USGS measured sediment transport rates and verified by reproducing the observed deposition of the reach between 2001 and 2007. Historical USGS flow data observed on the lower Puyallup River was used to create average annual flow‐duration curves used as hydraulic input into the model, while averaged NOAA observed tidal elevations for the mean high tide, mean sea level, and mean low tide within Commencement Bay were used as downstream hydraulic boundary conditions. Depositional trends in the model results were compared with existing trends noted in historical cross‐section comparison and gage adjustments to a nearby USGS streamflow gage. Results of the model show the bed elevations are expected to increase by as much as 5 feet over the next 50 years. The overall trap efficiency of the reach is expected to decrease as tidal influences begin to control the sedimentation processes over time.

Select this Article		Physical Experimentation and CFD Modeling to Evaluate Sediment Scour in Catchbasin Sumps Humberto Avila and Robert Pitt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)357 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The sediment removal capacity in catchbasin sumps and other hydrodynamic separators does not necessarily imply the ability to prevent the sediment from being scoured, especially when the remaining sediment capacity volume of the device is small and the flow rates are high. The sediment removal ability of catchbasin sumps and hydrodynamic separators must be balanced with their ability to retain the captured material by preventing scour. Therefore, understanding and quantifying scour processes in catchbasin devices is an important need when considering these devices as part of a stormwater management plan. This study investigated the sediment scour from a conventional catchbasin sump for different particle sizes, sediment depths, and flow rates. Full‐scale physical experimentation and Computational Fluid Dynamics (CFD) modeling were conducted to determine a wide range of conditions at which different particles sizes are scoured.

Select this Article		Sedimentation Characteristics of the Lower Nakdong River Upstream of the Nakdong River Estuary Barrage Sang‐Kil Park, M. ASCE, Un Ji, Byungdal Kim, and Dohoon Kim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)358 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Nakdong River Estuary Barrage (NREB) was constructed in 1987 to prevent saltwater intrusion and to provide the sustainable water supply in the upstream channel of the NREB. The upstream channel of the NREB has experienced sedimentation problems requiring annual dredging operation after the construction. The main purpose of sediment dredging is to prevent flooding during late summer. According to the past records, the annual average dredging volume is about 524,170 m₃ in the upstream channel of the NREB. Fluvial changes and sedimentation problems have been continued due to urbanization and development in the watershed as well as construction and management (sediment dredging) of the NREB. However, the sufficient field monitoring and researches for sedimentation characteristics and bed changes have not been performed after construction of the NREB. Therefore, bed elevation changes for 14 years (1990–2003) after construction of the NREB were analyzed using the Hec‐6 model and relatively short term changes of bed elevation were simulated using RMA2 and SED2D programs with field data to review the superficial changes. Field survey before and after sediment dredging was conducted at various points of time to examine the natural flushing effect of sediment by moderate and high discharge before flood season (late July to early September) during low tide.

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SEDIMENTATION II

Select this Article		Experimental Results on the Stability of Non‐Cohesive Sediment Beds Subject to Vertical Pore Water Flux Pinar Cakir Kavcar and Steven J. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)359 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Due to conflicting conclusions in the literature, this study considers the influence of vertical pore water flux on the initiation of motion criterion for noncohesive bed sediments subject to an applied shear stress. A key issue with respect to interpretation of experimental results may be associated with the determination of bed shear stress, a quantity that cannot be measured directly and thus relies on indirect methods to estimate. Another issue is the determination of the key variable characterizing the bed seepage as many studies characterize seepage in terms of the velocity while others account for the piezometric head gradient. A modification of the traditional Shields' parameters to account for the effects of bed seepage was developed suggesting that the bed hydraulic gradient is the key parameter in characterizing initiation of sediment motion. Experiments were performed for three different sand sizes subject to both vertically upward and downward bed flow to test the validity of the formulation over a wide range on the Shields curve. Experimental results interpreted using the modified dimensionless shear stress are shown to be consistent with the conventional Shields curve.

Select this Article		Suspended Sediment Concentration Measurements of Muddy Sediments with an ADV M. Salehi and K. B. Strom ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)360 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a laboratory study which examines the relationship between suspended sediment concentration and the signal to noise ratio recorded by a Nortek Vectrino Doppler velocimeter for two velocimeter acoustic output power levels. Tests are conduced in a tank with tap water and Kaolin clay for the concentration range of 0.0008 – 2.8 g/L. Results indicated that the velocimeter signal to noise ratio saturates at approximately 10 mg/L for a High power level setting and at 100 mg/L for a Low+ level power setting. For concentrations less than the saturation condition, the signal to noise ratio was found to be proportional to the logarithm of concentration, indicating that the velocimeter is a useful tool for measuring synchronized velocity and suspended sediment concentration time series.

Select this Article		The Connectivity of Upland and Instream Processes Athanasios (Thanos) N. Papanicolaou and Philip Ellis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)361 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The transport dynamic and fate of sediments in rivers is closely interrelated to upland activities within a watershed. Commonly, much of the degradation of surface waters in rivers is linked to excessive fine sediment and sediment‐bound pollutants coming from the uplands. Phosphorus, some pesticides, most metals, and many organic compounds are transported to the stream primarily adsorbed to fine sediment. Different land use activities in a watershed contribute to the increased influx of fine sediments and pollutants into streams. This research seeks to provide a methodology to qualitatively describe the inputs from the uplands into a stream segment, i.e., to account for the connectivity of upland and instream processes. In order to link fate of sediment within the river with upland activities, this research aims to integrate two models, namely, WEPP an upland non‐point source pollution model with 3ST1D, an instream model that can handle inputs of silts and clays. The analysis is performed in the Clear Creek Watershed of Eastern Iowa using existing data for model calibration and verification.

Select this Article		Upstream Intrusion Effect of CSO Event in Bubbly Creek, IL Xiaofeng Liu, Sumit Sinha, Davide Motta, and Marcelo H. Garcia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)362 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bubbly Creek is a tributary of the Chicago River, IL. It is used mainly as a Combined Sewer Overflow (CSO) route to the Chicago River. The CSO events from the Bubbly Creek carry sewers into the main channel and have a great impact on the overall water quality downstream. The sewer water mixed with particles usually has a higher density than the ambient water in the main channel. Upstream intrusion of sewer water is possible during the CSO event. In this paper, the three‐dimensional environmental fluid dynamics code (EFDC) is used to simulate the CSO event in Bubbly Creek. The main purpose is to investigate the extent of the upstream intrusion and its implications for the water quality effects on the Chicago River. The results show that the front location is a function of the relative CSO flow and the CSO particle concentration.

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STREAM RESTORATION I

Select this Article		A Simple Analytical Design Method for Small Alluvial Channels Bruce M. McEnroe, John E. Shelley, and C. Bryan Young ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)363 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an analytical design method for realignment of small alluvial channels with non‐cohesive bed material. This method follows the general approach recommended by the U.S. Army Corps of Engineers and the Natural Resources Conservation Service. The realigned reach is designed to convey the same bankfull discharge and sediment load as a stable reach directly upstream. The length, slope, sinuosity and cross‐sectional dimensions of the realigned reach are obtained from an analytical solution to Manning's equation for flow resistance and a simplified version of the Meyer‐Peter and Muller equation for bed‐load transport. The bankfull width and meander wavelength are obtained from geomorphic relationships for stable natural streams. Consequently, the realigned reach should have stable geomorphic characteristics that are typical of a natural stream in a similar setting.

Select this Article		Bankfull Discharge for Kansas Natural Alluvial Channel Design J. Shelley, C. B. Young, and B. McEnroe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)364 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In this study we present an equation that predicts bankfull discharge for Kansas streams based on watershed characteristics. This equation can be used for natural channel design projects such as stream realignments and restorations. To develop this equation, we first determined that the recurrence intervals of bankfull flow on 46 natural streams in Kansas range between <1.0 and 1.7 years. The median and mean recurrence interval are both 1.2 years. We then derived a multivariate regression equation for the 1.2‐year discharge from a database of 72 small rural streams in Kansas, using ten different watershed characteristics as possible predictors. The regression analysis led to an equation that predicts the 1.2‐year discharge as a function of the drainage area, the mean annual precipitation, and the length of the longest flow path. This equation can be used for natural channel design in Kansas.

Select this Article		Sediment Load Based Single Thread Alluvial Channel Classification Gregory Wilkerson and Gary Parker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)365 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Past studies have demonstrated the relation between channel‐perimeter sediment type (i.e., the weighted mean percent silt‐clay in the channel and banks, M) and channel shape (i.e., the width‐depth ratio). Moreover, M was found to be an indicator of the predominant sediment transport mode. Motivated by the reasoning and results of this earlier work we propose a classification scheme for single thread rivers that relies on the median bed material grain size (D₅₀) to classify streams as predominantly transporting either a fine suspended load (D₅₀ < = 0.062 mm), coarse suspended load (0.062 mm < D₅₀ < = 0.50 mm), mixed load (0.50 mm < D₅₀ < = 25.0 mm), or bedload (D₅₀ > 25.0 mm). For classifying channels, we use Shields curve to define conditions of incipient sediment motion and the criterion u_∗ = w_s (u_∗ = shear velocity and w_s = sediment fall velocity) to define the onset of significant suspended load transport. This work is warranted because in most studies of rivers and canals the D₅₀, rather than M, is the only measure recorded for describing channel‐perimeter sediment type. Distinctive relationships between B_bf and Q_bf, and H_bf and Q_bf are noted for each of the stream classes we propose, that is, trendlines for these variable differ systematically between stream classes. In contrast, width‐to‐depth ratios for the stream classes are not distinctive; the width‐to‐depth ratios range from 3 to 100 across all stream types and values as large as 1,000 are common for coarse suspended‐load streams.

Select this Article		Using Watershed Scale Geomorphic Assessment to Improve Urban Stream Restoration Design Sue L. Niezgoda, Ph.D., P.E., Aff. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)366 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The initial phases of a stream restoration project typically include a watershed geomorphic assessment to classify, identify, and assess a variety of environmental problems that can occur over a fairly large geographic area. There are three phases of geomorphic assessment at the watershed‐scale, including the desktop phase, the qualitative field study phase, and the quantitative field study phase. Each phase successively offers more detailed information on system‐wide instability; however, each phase also successively requires more resources to implement. An evaluation of the methods involved with each phase of assessment is needed to offer the restoration community guidance on selecting a method or combination of methods that can be used to assess system‐wide stability based on time and funding constraints. This paper examines existing quantitative and qualitative assessment techniques, the strengths and weaknesses of those techniques, and their applicability to urban stream restoration design. In particular, those methods that are most beneficial to urban stream restoration are examined and how they can potentially be used to improve the stream restoration design effort by focusing on the watershed scale. An example of the selection and application of qualitative and quantitative assessment techniques to an urban stream restoration design in Bloomington, Indiana is also presented.

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STREAM RESTORATION II

Select this Article		Habitat Restoration on the Middle Fork John Day River E. R. Holburn, T. Turner, L. Piety, and R. E. Klinger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)367 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Multi‐disciplinary stream assessments are currently being conducted on tributaries to the Columbia River, including the Methow, Wenatchee, Entiat, and John Day River Basins. The primary objective of these studies is to develop an improved understanding of the physical processes acting on the watershed to identify river restoration opportunities that address limiting factors of ESA‐listed species. This objective is met through interpretation of the biological conditions, including the fisheries and vegetation ecosystems, the geologic setting, anthropogenic constraints, geomorphic processes, basin hydrology, and hydraulic and sediment transport processes. Local knowledge, compiled data and modeling results are synthesized to evaluate potential physical and biological response to restoration actions. In particular, hydraulic modeling, sediment transport analyses, and geomorphic studies help define the spatial and temporal scale of river processes and offer a predictive tool to assess proposed actions. This paper presents an example of how this objective is being accomplished along a 23‐mile reach of the Middle Fork John Day River located in northeastern Oregon. Results of these investigations assist other technical staff, resource managers, planners, and stakeholders in determining how and where to focus resources for implementation of identified restoration projects. In this paper, we also illustrate a scientific methodology for evaluating the linkages between fluvial processes and biological response to proposed habitat improvements and present results from a two‐dimensional hydraulic model to quantify potential increases in floodplain connectivity and channel complexity.

Select this Article		Hungry Canyons Alliance: Streambed Stabilization in Western Iowa J. T. Thomas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)368 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Hungry Canyons Alliance (HCA) was formed locally to provide financial and technical assistance for streambed stabilization projects in the 19 counties of the deep loess region in western Iowa. Stream straightening and land‐use changes, coupled with the erosive nature of loess, caused streams to downcut and widen, undermining bridges, farmland, and utility lines. The most efficient and affordable way to stop channel degradation has proven to be the construction of grade control structures (GCS). GCS allow a drop in stream elevation in a controlled setting, prevent further degradation, decrease sediment loads and turbidity, and increase water quality. With over 750 GCS of all types in western Iowa, western Iowa has been referred to as a “laboratory” for GCS design. The HCA has conducted research on GCS design and fish passage, the use of directional drilling to control gully erosion, the use of scrap tires in GCS, knickpoint migration, and aerial stream classification.

Select this Article		Rehabilitation of Mine Impaired Creek in Idaho Brian Murphy, P.E., PH, CFM, Moosub Eom, Ph.D., PE, Bill Adams, and Jeff Johnson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)369 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The stream rehabilitation design for Tributary Creek in the Coeur d'Alene National Forest, Shoshone County, Idaho, was performed using the following general design concepts: reference reach selection, stream geometry and slope modifications, evaluation of stream habitat features, and channel stability. The stream rehabilitation used undisturbed reference reaches and the Rosgen method to aid in stream rehabilitation design. An overview of the hydraulic modeling and U.S. Fish and Wildlife Service Habitat Suitability Index (HSI) models for the target species will be presented in addition to design plans.

Select this Article		The Value of Protecting Ozark Streams: An Economic Evaluation of Stream Bank Stability for Phosphorus Reduction E. Dove, K. Rodgers, and M. Keener ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)370 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract One of the many appealing features of the Ozarks is the quality and beauty of our lakes and streams. Frequent algae blooms in the James River arm of Table Rock Lake however threatened not only valuable tourism dollars but also the quality of Ozark life. A nutrient based TMDL focusing on phosphorus and nitrogen was adopted for the James River in 2002. As we move into implementation, the question of the most cost effective method to reduce phosphorus loads is paramount. This paper compares the local cost of phosphorus removal from point sources as well as non‐point sources. Specific Ozarks examples investigated included phosphorus reduction from a waste water treatment plant, stormwater BMP's, stream buffers and stream stabilization. The paper findings indicate Stream restoration is an excellent solution to preventing this phosphorus from being transferred to Ozark lakes and is cost efficient when compared to other non‐point source reduction strategies. This paper briefly introduces the audience to many other economic benefits to stream restoration such as flood attenuation, greenways trails, and home price increase.

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STREAM RESTORATION III

Select this Article		Developing Probability of Failure Estimates for Stream Restoration Design Components Timothy M. Sliwinski, S. M. ASCE, Sue L. Niezgoda, Ph.D., P.E., Aff. M. ASCE, and Michael DeVasher, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)371 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Stream restoration projects are proliferating in all regions of the country to provide improvements to streams disturbed by highway construction, urbanization, and channel modifications. The morphologically‐based natural channel design method is commonly used to design stream restoration projects; however, the design approach is often vague, qualitative, and lacking in guidance. This can lead to an increase in project uncertainty and costs. A two‐step method of incorporating uncertainty and risk in stream restoration design has been developed as a combination of Design Failure Modes and Effects Analysis (DFMEA) and risk quantification. The purpose of DFMEA is to prioritize failures in accordance with their risk. The definition of risk contains two components: (1) probability of failure and (2) consequence of failure. Probability of failure of stream restoration design components is often difficult to determine due to lack of published failure data. In the existing risk assessment method, the likelihood of occurrence ratings from the DFMEA are used to estimate the probability of failure. A set of tasks were carried out to improve the application of the two‐step risk assessment method by developing better estimates of probability of failure for stream restoration design components. A literature review was performed to compile potential failure modes, causes of failure, associated predictor variables, and uncertainty in the predictor variables for stream restoration design components. Following this, advanced probabilistic techniques, namely Logistic Regression Analysis (LRA) and Monte Carlo Simulation (MCS), were applied to develop improved failure probabilities for stream restoration design. MCS was used to incorporate the results of the literature review and to select values for the predictor variables for use in the LRA. The LRA provided a model that was used for prediction of the probability of occurrence of an event. The results were incorporated into the existing risk assessment method to create a better decision making tool for stream restoration design. The incorporation of the resulting risk assessment method in the design phase of stream restoration projects can be important to decision making and will improve the likelihood of success.

Select this Article		Bedload Composition and Development of 2D Stream Sediment Model for Stream Restoration Design Applications in Urbanizing Watersheds William R. Cantrell, E.I., John S. Schwartz, Ph.D, P.E, and William K. Barry, P.E., D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)372 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A central problem in the field of stream restoration is that of designing a stable channel that supports a healthy benthic population. Many stream restoration projects take place in urban or urbanizing watersheds. The relationship between changing watershed characteristics and local channel conditions within that watershed is poorly understood. This study is made up of two major components that address aspects of this problem: first, a physical study of bedload flux in watersheds representing rural, urban, and developing conditions and second, verification of results from the Computational Hydraulic Engineering Two‐Dimensional Sediment Model (CCHE2D) on the reach scale and correlation of CCHE2D results with Rapid Bioassessment Protocol III (RBP III) scores. Study sites were selected in Knox County, Tennessee including twelve sites for the bedload study and a single site for the CCHE2D model verification. The bedload flux portion of the study combines field collection of bedload via portable bedload traps and an estimate of energy slope from peak stage recorders. Information derived from the field collection will be combined with watershed data via geographic information system (GIS) analysis. Watershed metrics including percent impervious area, roadways adjacent to streams, and average watershed slope determined via GIS will be correlated with the measured bedload composition for each research site. The CCHE2D model verification will combine the study of bedload flux with a previous study correlating the surficial bed material composition with macroinvertebrate biotic integrity scores (RPB III) for 76 reaches in East Tennessee. The combination of this information will provide a valuable tool in stream restoration design in allowing practitioners to have an empirical metric with which to design/predict channel substrate composition as an indicator of physical habitat quality.

Select this Article		Two‐Dimensional BOD and DO Water Quality Model for Engineering Applications: The Case of Bubbly Creek in Chicago, Illinois Davide Motta, Jorge D. Abad, Xiaofeng Liu, and Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)373 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Bubbly Creek was historically used as a drainage channel for the waste resulting from Chicago's stockyards. Nowadays there is flow in the creek only during rainfall events resulting in Combined Sewer Overflows (CSO) and water quality is a very important issue, particularly during the summer months, when the dissolved oxygen levels are extremely low and sediment oxygen demand is expected to be large. Due to the particular flow regimes of the creek and the conditions of the benthic sediments in the bed, a special BOD‐DO (Biochemical Oxygen Demand ‐ Dissolved Oxygen) water quality module was developed and implemented into the two‐dimensional depth‐averaged numerical model STREMR‐HySedWq. The approach illustrated represents a substantial improvement to the state‐of‐the‐art of water quality modeling methodologies. The model was able to capture the key processes and provide useful preliminary results for the two following scenarios: [1] CSO events, for which the model was coupled to a one‐dimensional cross‐section‐averaged BOD‐DO water quality model, and [2] potential “purification” solutions, such as flow augmentation and supplemental aeration, with the goal of increasing the DO levels in the creek during dry weather periods.

Select this Article		Using HEC‐RAS Hydraulic Design Functions for Geomorphic Channel Design and Analysis John Shelley and A. David Parr ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)374 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Copeland method for designing geomorphologically stable channels has been included in the Army Corps of Engineers' Hydraulic Engineering Circular River Analysis System (HEC‐RAS). This method requires the bottom width, depth, and side slopes of a representative cross‐section from a stable, upstream reach as input. This assumes the upstream cross‐section can be approximated by a trapezoidal channel, but no instruction on how to derive this trapezoidal approximation is given in available literature. Additionally, the method requires a side‐slope Manning ‘n’ value, for which the available documentation provides only qualitative guidance. This paper presents a step‐by‐step design example for using the Copeland method, including approximating the upstream channel as a trapezoid and calculating the sidewall Manning ‘n’.

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STREAM RESTORATION IV

Select this Article		A Monitoring and Assessment Framework to Evaluate Stream Restoration Needs in Urbanizing Watersheds John S. Schwartz, Sue L. Niezgoda, Louise O. Slate, Donald D. Carpenter, William K. Annable, Tess M. Wynn, Christine Pomeroy, and Munsell McPhillips ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)375 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Urbanization has a significant impact on rivers and streams, modifying flows, sediment loads, channel morphology, water quality and nutrient processing, and aquatic biota. Because of these impacts, a majority of the streams in urban and urbanizing watersheds are reported on §303(d) state lists as impaired from siltation, habitat alteration, nutrients, bacteria, and other stressors. States are required to develop total maximum daily loads (TMDLs) under 40 CFR 130, and watershed‐scale implementation plans are produced to rehabilitate impaired streams by achieving target TMDL allocations. Stream restoration practices are commonly used as corrective measures to meet TMDLs, particularly for siltation and habitat alteration. However, urban stream restoration typically consists of reach‐scale projects that may not be well integrated into a watershed corrective plan. Rather, project scope and location are commonly determined by local perceptions of need and accessibility. Watershed planning is needed in urbanizing watersheds for various reasons. Most importantly, planning is needed because hydrology and sediment loads change as developments occur over time until ultimate build‐out, and future infrastructure constraints affect channel planform stability. These reasons underscore the critical need for restoration projects to be implemented based on a watershed plan, and a plan that integrates implementation of stormwater management best management practices (BMPs). The objective of this paper is to present a framework for monitoring and assessment protocols for urban and urbanizing watersheds, with the aim to better support planning of stream restoration projects and improve restoration outcomes. This is the product of a joint task committee by the Urban Stream Committee of the Urban Water Resources Research Council and the River Restoration Committee of the Hydraulics and Waterways Council.

Select this Article		Post Project Appraisal of Riparian, Wetland, and Aquatic Habitat Restoration at Best Slough, Beale Air Force Base, Marysville, CA M. R. Tompkins, D. Mengel, and T. Hamaker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)376 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Best Slough flows through Beale Air Force Base and used to come into contact with groundwater contaminated by trichloroethene (TCE) at Site 17 during low flow periods when it was a gaining stream. An interim remedial action was developed for Site 17 to halt further migration of the contaminated groundwater plume by surrounding it with a slurry wall and establishing a phytoremediation system on top of the site within the slurry wall. The portion of Best Slough in contact with the contaminated groundwater plume was realigned upgradient of the plume with more natural channel morphology and riparian vegetation as well as sufficient hydraulic capacity and channel stability to protect the remedial features on the site. Channel banks were designed with terraced slopes to provide additional acreage for riparian vegetation habitat. Side‐channel islands were included in the channel design to provide isolated riparian habitat for waterfowl as well as for aquatic reptiles and amphibians. A complex of deep‐water channels was incorporated into the design to provide rearing habitat and thermal refuge for warmwater fish. And all channel features were incorporated, where possible, into the overall erosion control and bank stability design for the channel. Project construction was completed in 2000, and periodic site visits have documented development of aquatic and riparian habitat features and performance of the channel realignment and restoration elements of the project with respect to their design objectives. We summarize observations of channel, riparian, and vegetation performance over the past eight years and present lessons learned from this complex, multi‐objective river restoration project.

Select this Article		Predicting Streambank Seepage Flows: Sensitivity to Soil Properties and Layering D. M. Heeren, G. A. Fox, M. L. Chu‐Agor, and G. V. Wilson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)377 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Streambank failures result in loss of land and increased stream sediment loads. Variably saturated flow models integrated with bank stability models are being used to predict bank failure; however, understanding of the level of soil characterization necessary to predict when seepage contributes to bank failure is needed. ROSETTA, a pedotransfer function, was used to estimate hydraulic parameters for various levels of soil data (from texture class to saturated hydraulic conductivity, K_s). A two‐dimensional groundwater flow code, SEEP/W, was used to model a hypothetical streambank and estimate seepage velocity. Results suggested that K_s and/or percent clay measurements are necessary to adequately predict seepage. A layered bank was also simulated with several combinations of soil types. Results indicated that only one order of magnitude difference in K_s (equivalent to a resistance ratio of 10) may be necessary to induce perching and seepage from the top layer. This research suggested that, if a field reconnaissance is performed to locate streambanks susceptible to perching, K_s and/or bulk density measurements are necessary to indicate the presence of a restrictive layer.

Select this Article		A Seepage Erosion Sediment Transport Function and Geometric Headcut Relationships for Predicting Seepage Erosion Undercutting M. L. Chu‐Agor, G. A. Fox, and G. V. Wilson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)378 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Seepage erosion is an important factor in hillslope instability and failure. However, predicting erosion by subsurface flow or seepage and incorporating its effects into stability models remain a challenge. Limitations exist with all existing seepage erosion sediment transport functions, including neglecting the three‐dimensional geometry of the seepage undercut. The objective was to develop a sediment transport model that can predict sediment mobilization (i.e., seepage erosion and undercutting) with time based on previously reported three‐dimensional soil block experiments covering a wide range of hydraulic, soil type, and packing (i.e., slope and bulk density) combinations. The transport function was represented by an excess velocity equation wherein the rate of erosion was related to the difference between the steady state velocity and the critical velocity (R² = 0.62). The critical velocity was derived from a critical head measured in the laboratory using the three‐dimensional soil block. The relationship between the eroded volume per bank face area and the amplitude of the headcut was also derived. Using a three‐dimensional Gaussian function, the geometric relationships between the lateral and vertical dimensions of the headcut were then estimated. Linear regression analysis between the predicted and observed time at which a given amount of headcut developed resulted in an R² of 0.86. The ground water velocity exfiltrating a hillslope can be used with the derived sediment transport function to predict the dimensions of the headcut and the geometry of the undercut which enables the prediction of the impact of seepage erosion undercutting on hillslope stability.

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IMPROVING HYDROLOGIC PREDICTION IN DEVELOPING COUNTRIES

Select this Article		A Blueprint for Advancing Hydrologic Predictability in Developing Countries: A Case Study for the Nile River Basin M. Gebremichael ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)379 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Lack of reliable hydrologic monitoring and prediction tool in the Nile River basin is hindering the planning and management of water resources in the region. This paper presents the broad outlines of an emerging approach for improving hydrologic monitoring and predictability in the Nile basin. The new approach embraces the space‐time heterogeneities of hydrologic processes, and the integrative observations‐modeling uncertainty in characterizing those processes. Instead of relying solely on sparse ground‐based measurements, it will take advantage of recent developments in satellite remote sensing technology to observe space‐time patterns of hydrologic variables. It will acknowledge the various observational and modeling error sources, and quantify the residual errors. Instead of using hydrologic models that have not been proven to work in the Nile basin, it will seek to identify the level of complexity needed maximize the performance of models driven by satellite datasets for the Nile basin. The defining feature of the new approach will be a sharp focus on the use of satellite data, hydro‐meteorological models of appropriate complexity, establishment of a ground validation site and implementation of field campaigns for error characterization. This new focus will advance hydrologic monitoring and predictability in the Nile basin, and improve the accuracy of water balance components that would feed directly into the making of more‐efficient, more‐equitable and better‐informed water management and planning decisions.

Select this Article		Distributed Hydrologic Model for Flood Prevention in the Yuna River Watershed, Dominican Republic H. J. Robinson, Z. Fang, and P. B. Bedient ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)380 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Yuna River basin, a watershed of about 5500 km² in the Dominican Republic (DR), is affected by both broad floods in the valley and flash flooding in the upper mountainous reaches. A better understanding of flood behavior and an assessment of flood control options is necessary in this watershed to protect human life and property, as highlighted by the particularly active 2008 hurricane season. Distributed hydrologic models using Vflo™ of both 250m and 500m cell resolution have been developed to provide flood prediction and flood control assessment in the basin. The Upper Yuna subwatershed is topographically diverse, with steep tributaries falling from 3,000m mountains into a main channel through a relatively flat valley. The Vflo software has great applicability for this watershed compared with more standard hydrologic models because it can model the challenging topography, provide flow outputs for any portion of the watershed, and handle variable‐detail GIS inputs of elevation data, soil, and land‐use maps. An analysis has been performed that compares influence of cell size and hydrologic detail on tributaries of varying steepness and flow output, which proves important for location selection of flood control options. A main goal of this work is to aid this flood‐prone community by getting a first model running that can provide inputs to flood timing prediction, basic floodplain mapping, and flood control assessment, but that can be quickly refined as more data of greater detail becomes available.

Select this Article		Evaluation of Land Use Land Cover Changes in Palleru (K‐11) Sub Basin of River Krishna Using GIS and NDVI M. V. S. S. Giridhar and G. K. Viswanadh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)381 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the present study, Palleru sub basin (K‐11) has been considered for the evaluation of land use land cover changes. Ten rain gauge stations were identified in and around the study area and accordingly the sub basin was divided into ten sub areas namely Palakurthy, Kodagandla, Torrur, Tungaturthy, Aravapally, Maripeda, Noothankal, Atmakur, Kushmanchi and Mothey based on Thiessen polygon network. The land use/land cover classification was made based on Normalized Difference Vegetation Index (NDVI) with two scenes in a year. The areal extent of bare soil was computed as 26.16 sq km and 372.03 sq km for the years 2000 and 2002 respectively in the Rabi season and 87.73 and 182.82 sq km for the years 2000 and 2002 respectively in the summer season. Bare soil increased by 345.87 sq km and 95.09 sq km in Rabi and summer seasons respectively. The areal extent of fallow lands with bushes decreased from the year 2000 to 2002 with respect to Rabi and summer seasons due to limited rainfall in the year 2002. However, the cropped area did not register much difference. The areal extent of water bodies in Rabi season was estimated as 198.83 sq km and 92.57 sq km for the years 2000 and 2002 respectively. The decrease in water spread area from the year 2000 to 2002 was due to corresponding decrease in rainfall in the study area from 920mm to 556 mm. Similarly, the areal extent of water bodies in summer season was estimated as 22.74 sq km and 18.27 sq km for the years 2000 and 2002 respectively.

Select this Article		On the Local-Scale Spatial Variability of Daily Rainfall in the Highlands of the Blue Nile: Observational Evidence Menberu M. Bitew, M. Gebremichael, F. A. Hirpa, Y. Michael, Y. Seleshi, and Y. Girma ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)382 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The HEXB (Hydrological EXperiment in Blue nile) experiment provided an opportunity, via dense network of rain gauges, to study the spatial variability of daily rainfall at a 5 km × 5 km scale in a tropical and mountainous part of the Blue Nile river basin, for the period of July 1 – August 9, 2008. The results of daily rainfall spatial analyses are shown in this paper. High intensity rainfall events have more absolute spatial variability (e.g., standard deviation) and less relative spatial variability (as measured by coefficient of variation), compared to lower intensity events. The coefficient of variation varies from 12% to 320%, with a median of 50%, indicating that there is a significantly large variability from one gauge observation to the other, and one gauge does not represent 5 km × 5 km grid-average daily values. A careful rain gauge layout design is critical to get accurate estimates at smaller number of rain gauges.

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INTERNATIONAL WATER RESOURCES PLANNING AND MANAGEMENT

Select this Article		Characteristics of Integrated Water Resource Management in the Zambezi River and Great Lakes Basins: A Comparison of Two Approaches Jonathan W. Bulkley, Imasiku Nyambe, and Christine J. Kirchhoff ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)383 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Integrated Water Resources Management (IWRM) is evolving as a contemporary means to address complex and critical issues associated with making the most effective and efficient use of water resources. Water resource challenges in the Zambezi River Basin include both quality and quantity issues including potential diversions from the basin to localities outside the basin and lack of an agreed upon institutional framework for the management of the Zambezi River system. In 1972, the United States and Canada signed the first Great Lakes Water Quality Agreement. This agreement committed the two countries who share the trans‐boundary waters of the Great Lakes to restore and enhance water quality in the Great Lakes System. Amendments in 1987 resulted in establishing the goal to virtually eliminate persistent toxic substances into the Great Lakes resulting from human activities. In 2008, the Great Lakes Compact was approved by all of the eight Great Lakes States plus the Provinces of Ontario and Quebec. This compact was subsequently approved by the Congress of the United States and signed by President Bush on October 3, 2008. Both the Zambezi River Basin and the Great Lakes Basin offer valuable insights into the application of IWRM to critical water resource planning and management challenges in their respective geographical locations.

Select this Article		Determining the Causes of Declining Upper Great Lakes Levels — Phase I of the International Upper Great Lakes Study by the St. Clair River Task Team Anthony J. Eberhardt and Syed M. A. Moin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)384 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of the International Upper Great Lakes Study (IUGLS) is to investigate improvements to the regulation of the outflow of Lake Superior given the impacts regulation may have on water levels, flows, and consequently affected resources throughout the upper Great Lakes system. It also is closely examining the physical processes driving current Great Lakes water level conditions, and possible ongoing changes in the St. Clair River and their impacts on river flow and Lakes Michigan and Huron levels (Phase I). The issues are being investigated by two Task Teams (TTs): the Lake Huron Outflow/ St. Clair River Task Team (SCR TT) and the Lake Superior Regulation Task Team (LSR TT). This paper describes the investigations being conducted by the SCR TT for Phase I of the Study which is scheduled for completion in October 2009. The entire Study will be completed in April 2012.

Select this Article		Economic Sustainability Evaluation of an Inter‐Basin Water Transfer Project Using GWP Statement Mohammad Karamouz, S. Ali Mojahedi, Asghar Elyasi, and Vahid Askarinejad ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)385 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract One of the strategic components of progress in societies is Water Resources Development Projects that have a key role for expanding regional infrastructures in safe and affordable water. These plans have direct and indirect economic impacts. In order to measure them, one needs to consider different parameters affected by regional conditions and project characteristics. Among the newest approaches to utilize water is to evaluate it as a “socio‐economic good”. Global Water Partnership (GWP) guideline has been developed using this point of view. It follows economic sustainability evaluation in water projects and considers two main terms of full cost and full value. The former consists of: Full Supply Cost, Opportunity Cost, Economic and Environmental Externalities, and the later includes: Economic Value and Intrinsic Value. This statement explains that economic sustainability will be attained when the full value is equal or greater than the full cost of the project. In this paper, evaluation of economic sustainability based on GWP guidelines has been applied for an Inter‐basin Water Transfer Project (IWTP) in Iran. The goal of this project is to supply water from the Karoon River in the South‐Western part to the central region in Iran for agricultural activities. For this purpose, different components of the project are identified, and then its full cost (such as capital investment, loss of revenue from hydropower generation and crop production and the cost of improving water quality in the basin of origin) and full value (such as benefit from agricultural production, aquifer restoration) are calculated by using a simulation model and an accounting method. The results show the value and cost of each component of the project as a basis for identifying the stable economic elements of the project. Finally, certain recommendations for improving the sustainability of the system are presented.

Select this Article		Recent Developments in Water Policy in the Americas Mark W. Killgore, P.E., D.WRE, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)386 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper reviews recent work by EWRI, AWRA, ANEAS, FECIC and other entities actively developing water policy statements in preparation for the Fifth World Water Forum, scheduled for Istanbul, Turkey, March 16 through 22, 2009. EWRI participated in many of the preparatory events including: 1) International Symposium on the 5th World Water Forum held in conjunction with the EWRI World Environmental & Water Resources Congress 2008 in Honolulu Hawaii in May 2008. 2) Fourth National Water Resources Policy Dialogue, September, 2008, Washington, DC (sponsors included AWRA, EWRI and NWF). 3) 22^nd Annual Convention of ANEAS and the North American Regional Water Forum, Guadalajara, Mexico, November, 2008. 4) Mexican Federation of Colegios (Sections) of Civil Engineers' (FECIC) 2^nd World Congress on Water and Climate Change, Merida, Yucatán, Mexico, November 2008. and 5) Water Forum of the Americas, Iguazu Falls, Paraná, Brazil, November 2008.

Select this Article		The Memorandum of Understanding (MOU) between the University of Zambia and the University of Michigan Conception and Subsequent Implementation Goals Jonathan W. Bulkley, Imasiku Nyambe, and Christine J. Kirchhoff ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)387 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In April 2008 the University of Michigan and the University of Zambia signed a Memorandum of Understanding (MOU) that approved a cooperative agreement to foster the development of a collaborative research and exchange program focused on concepts of integrated water resources management (IWRM) to be applied in the Zambezi River Basin in Southern Africa and the Great Lakes Basin in the U.S. The Zambezi River Basin, home to nearly 40 million people, is the largest river basin in Southern Africa covering 1.37 million square kilometers in eight countries. The Great Lakes Basin watershed is home to about 40 million people living in eight U.S. States and two Canadian Provinces and covers over 1/2 million square kilometers.

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RURAL WATER SUPPLY SYSTEMS IN DEVELOPING COUNTRIES

Select this Article		Environmental & Water Resources in Developing Countries: Development of Micro Irrigation Facility at Parsoda Village P. K. Agale, N. N. Wankhede, P. B. Bhave, and S. Y. Mhaske ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)388 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract India is developing country among the world. Most of the people in India depend on agricultural industry. Near about 70% population depends on agriculture. Hence, India's development mostly depends on development of agricultural sector. But it is very difficult to construct big dams across the rivers due to environmental damage and protest of farmers against acquisition of land. Also major or medium irrigation project cannot provide the irrigation benefit to every farmer. Due to scarcity of water for irrigation, one lac farmers did suicide in last ten years in India. If the micro irrigation facilities are provided then there will be considerable recharge of ground water aquifer take place. It will create agricultural reform without causing natural hazard. The present paper deals with development of micro irrigation facility at Parsoda village, district Aurangabad, Maharashtra State in India. In this project micro irrigation techniques like farm pond, earthen bunds are used for development of irrigation facility, near about 3500 acres of agricultural land is benefited due to micro irrigation technique with minimum expenditure.

Select this Article		Feasibility Study for Implementing Renewable Energy to Power a Groundwater Pump in Rural Guatemala Will Granich and Andrew Curtis Elmore ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)389 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Communities in rural Guatemala often struggle with obtaining adequate, clean drinking water. A deep groundwater well can provide a clean and sustainable water source for near‐by communities. To obtain the groundwater, an electric submersible pump must be installed in the well. Utility power in rural Guatemala can be unreliable and expensive, thus a study has been conducted to establish if using alternative energy is sustainable and economically viable for a groundwater pump for a rural Guatemalan community. The study focused on effectiveness, reliability and cost. A weather station was erected in Sacala las Lomas to collect baseline data for the feasibility study. Wind velocity, wind direction, solar radiation, temperature, precipitation and barometric pressure data were collected. The data were analyzed to determine the potential power generated with solar and wind power. Although the location was in a particularly superior location for sun and wind exposure, installing solar panels and/or a wind turbine would not be feasible for supplying the amount of energy required for a submersible groundwater pump that would meet the needs of the community.

Select this Article		Drinking Water Field Analyses for the Detection and Enumeration of Coliform Bacteria in Rural Guatemalan Highlands Jenna Tune and Andrew Curtis Elmore, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)390 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract An analysis of drinking water contaminant concentrations in the highlands of rural Guatemala evaluated the Coliscan EasyGel as a field method for the detection and enumeration of coliform bacteria in drinking water and found it adequate. In developing countries like Guatemala, many deaths among infants and young children may be due to dehydration, malnutrition, or other complications of waterborne bacterial infections. Students and engineers are challenged to find sustainable means to provide safe drinking water. A field applicable method of quantifying microbiological contamination is needed to improve the evaluation of engineering solutions. A pour plate method using the patented Coliscan EasyGel medium is commercially available and marketed for field use by Micrology Labs Incorporated. However, the validity of the field data is called into question when the results are compared qualitatively and quantitatively to duplicate Membrane Filtration (MF) analysis using M‐Endo medium, an ASTM accredited method. To evaluate comparability, this work splits subsets of the samples for duplicate MF analysis and non‐parametric statistical evaluation due to the non‐normal nature of data distribution.

Select this Article		Sustainability of Rural Water Supply Projects in Nicaragua Jairo Hernandez Alvarado ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)391 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Access to safe and freshwater service without sustainability is a critical issue for many developing countries. From the past decade, Nicaragua has been working on increasing access to water and sanitation services with sustainability in rural areas through the Emergency Social Investment Fund (Fondo de Inversion Social de Emergencia, FISE) which is the governmental agency in charge of investments in rural water and sanitation solutions. The experience with rural water and sanitation rural systems began in 1977 with the Rural Basic Sanitation National Plan (PLANSAR). PLANSAR was designed to increase coverage of water and sanitation services, using technical solutions of the urban sector. During the period 1977 through 2000 there was no community participation at all. In 2000, The World Bank conducted an evaluation of the social fund and found that half of the sampled systems supplied water on a regular basis, and half supplied water on average only three days per week. The low supply systems experienced operations and maintenance difficulties. In these sampled systems, the operations and maintenance was under the responsibility of the central and municipal agencies and community participation and training was virtually non‐existent.

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TRANSBOUNDARY WATER ISSUES

Select this Article		Framework for Improving Water Security in the Middle East John A. Kliem, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)392 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Middle Eastern water demands are going to exceed the supply by 2040 potentially exacerbating an already tense situation. Any lasting peace plan needs to address scarce water resource commodities. All stake holders need to play a role in determining the allocation of water to ensure water security needed for further economic development. The United States as part of an international coalition needs to guide the Jordan River riparian states in the development of a regional water governance body to provide the required transparency to fairly allocate water resources and to ensure that water does not become the flash point for future Middle Eastern conflicts.

Select this Article		A War for Water Jonah‐Jong M. Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)393 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract It is the most precious commodity on earth, and billions of people do not have adequate means of obtaining it. Water both for drinking and sanitation use is essential to human life. Yet in a world where we have come so far in technological advancement, we still live amongst 2 billion people who do not have access to modern sanitation facilities and 1 billion people without safe and drinkable supplies of water. We have failed to address a problem that should have spurred world interest long ago. There are countries with millions of people, including children, dying each year due to a lack of clean drinking water and poor sanitation services. With a continuous rise in population throughout the world and an ineffective distribution of water resources, there can be as many as 140 million water‐related deaths by 2025.

Select this Article		Water Resources in Jordan: Challenges and Accomplishments S. Merayyan, S. Mrayyan, and M. Mihyar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)394 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Hashemite Kingdom of Jordan, or simply Jordan, is a small county located in the Middle East. Jordan has borders with Saudi Arabia, Syria, Iraq, and Israel (see Figure 1). Jordan was established in 1921 and has very limited natural resources. Jordan's current (2008) population is estimated to be 6.5 million. The country has a total area of 750,000 km2, about one third (92,300 km2) of which is dry land while the other two thirds (329,000 km2) is irrigated land.

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WATER QUALITY AND AQUATIC ECOSYSTEMS IN DEVELOPING COUNTRIES

Select this Article		Impacts of Mining in the Upper Zambezi River Basin: An overview of the Zambian Copperbelt Imasiku A. Nyambe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)395 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Zambezi River Basin (ZRB) is the largest river basin in Southern Africa, covering some 1.37 million square kilometers across eight countries: Angola, Botswana, Malawi, Mozambique, Namibia, Tanzania, Zambia, and Zimbabwe. It is home to approximately 30 million people who rely on the river for drinking water, fisheries, irrigation, hydropower production, mining and industry, ecosystem maintenance, and other uses such as tourism at Victoria Falls and wildlife viewing along the river banks. Water management in the basin is especially difficult because there are multiple countries with multiple and competing interests; competing issues other than water that demand time, attention, and money; inadequate basin‐level institutional structures; institutional, legal, economic, and human resource constraints within each country; and poor data collection, poor communication, and inadequate training. However, Zambia has a lion's share of the basin with 105.2km³/ac of water resources covering 75% of the country of a total area of 752,614 sq. km.

Select this Article		Improving the Water Quality of One of the World's Great Lakes: Tai Lake Case Study of Environmental Responsibility in the Developing World D. P. Albers, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)396 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract China's Tai Lake is one of the world's great lakes. Located in eastern China near the city of Shanghai, over 30 million people live within the lake's watershed. In 2007 Tai Lake experienced a major algal bloom, which resulted in the suspension of water supplies to Wuxi City. In response, the Chinese central government tasked the China Development Bank (CDB) with creating an environmental loan program to assist in improving the lake's water quality. Ecology and Environment, Inc. (E & E) was hired by the CDB to assist in identifying loan opportunities that could be used to improved Tai Lake's water quality. A principle finding was the willingness of local authorities to fund large‐scale environmental projects. Another significant finding was the recognition within the watershed of the need to shift funding away from wastewater treatment plants and toward measures to intercept polluted runoff from non‐point sources. The approach presented in this paper provides a model for developing countries to create effective and comprehensive environmental loan programs and the supporting strategies needed to help ensure their success.

Select this Article		Investigating Aquatic Ecosystems of Small Lakes in Khorezm, Uzbekistan Laurel Saito, M. ASCE, Julian Scott, Michael Rosen, Bakhriddin Nishonov, Sudeep Chandra, John P. A. Lamers, Dilorom Fayzieva, and Margaret Shanafield ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)397 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Khorezm province of Uzbekistan, located in the Aral Sea Basin, suffers from severe environmental and human health problems due to decades of unsustainable land and water management. Agriculture is the dominant land use in Khorezm, and agricultural runoff water has impacted many small lakes. In this water‐scarce region, these lakes may provide a water source for irrigation or fish production. Samples have been collected from 13 of these lakes since 2006 to assess water quality, the aquatic food web, and possible limits to aquatic production. Lake salinity varied from 1 to >10 g/L both between and within lakes. Although hydrophobic contaminants concentrations were low (82–241 pg toxic equivalents/mL in June 2006, October 2006, and June 2007), aquatic species diversity and relative density were low in most lakes. Ongoing work is focused on 4 lakes with pelagic food webs to estimate fish production and assess anthropogenic impacts on the food web. Lake sediment cores are also being examined for organic contaminants, and hydrology is being assessed with stable isotopes.

Select this Article		Prediction of Thermal Stratification in Proposed Bakhtyari Reservoir with CE‐QUAL‐W2 Mehrdad Nazariha, Erfan Danaei, Seyyed Hosein Hashemi, and Amir Hosein Izad Doustdar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)398 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Construction and operation of dams have two main effects on streams. At first it increases detention time and then leads to thermal stratification. Changing of water quality is the result of these effects and the outflow has different physical, chemical and biological characteristics from inflow. In this study thermal regime in proposed Bakhtyari reservoir was simulated with CE‐QUAL‐W2 model. The inputs are reservoir topography, hydrological and meteorological data. As there is no chance to calibrate or verify the model, they will be done in monitoring and operation period. Three different inflow scenarios were simulated based on dry, normal and wet year. Simulation results represent that in dry year stratification starts at April and remains up to September, but the results of normal year indicates that Stratification is between May and November. In wet year because of short detention time, thermal gradient variation is different from dry and normal year and temperature of middle layers imitate inflow water temperature. In all scenarios a stagnant layer could be seen in downward of outlet structure(700mASL). It is concluded that in dry years which dam has a major effect in inflow regime, turnover is mostly conform thermal stratification theories in reservoirs.

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CROP PRODUCTION AND WATER BALANCE

Select this Article		Physiological and Yield Response of Green Bell Pepper to Soil Moisture Sensor Controlled Drip Irrigation Lincoln Zotarelli and Michael D. Dukes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)399 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objectives of this study were to evaluate the physiological and yield response of pepper to different soil moisture thresholds using soil‐moisture‐sensor (SMS) irrigation control. Irrigation treatments were set at specific threshold of volumetric‐water‐content (VWC) which was allotted five irrigation windows/day and bypassed events if the VWC exceeded the established threshold. Treatments were: threshold of 4, 8, 12%VWC single irrigation‐drip at center of the bed (SS); threshold of 8, 12%VWC with double drip‐irrigation (SD); TIME_2h with fixed 2hr irrigation/day and TIME_4×24 with 4 fixed events of 30min/day. The use of SMS reduced irrigation water applied (81; 118; 138; 112; 201; 341 and 260mm for SS₄; SS₈; SS₁₂; SD₈; SD₁₀; TIME_2h and TIME_4×24, respectively). For the same order, the pepper yield was 26; 31; 35; 30; 42; 33; 41 Mg/ha. Water and NO₃–N captured in lysimeters were lower on SMS irrigation controlled compared to TIME based irrigation commonly used by producers.

Select this Article		Water Production Functions for High Plains Crops Thomas Trout, Gerald Buchleiter, and Walter Bausch ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)400 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Declining water supplies is the critical resource issue for irrigated agriculture in the High Plains and much of the western U.S. Farmers need to maximize production per unit water consumed to remain economically viable and sustain irrigated agriculture. The Agricultural Research Service (ARS) Water Management Research Unit is developing water production functions for High Plains crops that can help farmers make decisions for allocating limited water supplies among crops. The Unit has developed an irrigated research farm to measure total water balance for a 4 crop rotation (wheat, corn, sunflower, dry beans). The goal is to develop water production functions based on consumptive use, relate yields to soil water deficits and plant stress indicators, and improve existing plant growth models to more accurately reflect water stress effects. Results for the first year corn crop show both grain and total biomass yields nearly proportional to water consumptive use with water use efficiencies of 2.4 and 3.9 kg/m³, respectively.

Select this Article		Water Retention and Hydraulic Conductivity of Different Media Used for Containerized Agriculture Systems Vivek Kumar, M. Reza Savabi, Felipe M. Guerrero, and Berrin Tansel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)401 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Containerized plant production represents an extremely intensive agricultural practice and a large amount of water and chemical fertilizer is applied. Hydo‐physical characteristics such as water infiltration, texture and structure, particle size distribution affect the quality of the media used in containerized agricultural systems and the water availability to plants. Water retention characteristics depend on particle size distribution as well as the composition of the media used. Materials with coarser particles allow faster percolation of water and also retain relatively higher amounts moisture per unit weight due to higher porosity But drain faster due to less surface area.. Faster drainage can result into air flow through coarser materials causing the media to dry. As the media desaturates, hydraulic conductivity is reduced. The objective of this study was to analyze the different media used by nurseries to characterize the physical properties which would explain the soil‐water interactions. In this study we measured soil's hydraulic conductivity in the laboratory using three methods, constant head permeability test, falling head permeability test and tension Infiltrometer. The results were compared in relation to particle size distribution characteristics of samples. The results of the study indicate that the four common media being used in nurseries in South Florida have distinct hydro‐physical properties. The result of this should assist the land managers while selecting the Best Management Practices.

Select this Article		Water Use and Evapotranspiration Coefficients for Camelina Sativa D. J. Hunsaker, A. N French, T. R. Clarke, and D. M. El‐Sheikha ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)402 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The water use characteristics of Camelina sativa, an oilseed crop, were evaluated in an irrigation experiment in Maricopa, Arizona. Camelina (cv. Robinson) was grown between November 2006 and April 2007 in plots, each 10 by 17 m. Thirty‐two of the field plots were replicated in a randomized block design consisting of irrigation treatments of four levels of soil water depletion: 40, 50, 65, and 75%. Six supplemental plots evaluated water stress at 85% soil water depletion. Weekly soil water content measurements were obtained over a soil profile of 1.9 m for all plots using neutron probes. In January 2007, following initial irrigations uniformly applied to all treatments, treatments received one to four additional surface irrigations. The camelina extracted soil water to a depth of 1.5 m. The seasonal evapotranspiration, calculated from soil water balance data, varied from 285 mm for the water stress plots to 371 mm for the 40% treatment. Excluding the water stress plots, seed yields for treatments varied from 950 to 1130 kg ha⁻¹, though differences were not significant. Mid‐season camelina crop coefficients were on the order of 1.13 to 1.20. A camelina crop coefficient curve is presented as a function of days after planting.

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CURRENT IRRIGATION SCHEDULING ADVISORY SYSTEMS 1

Select this Article		Irrigation Scheduling for Deficit Irrigation Norman L. Klocke, P.E., Loyd R. Stone, and Dale A. Bolton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)403 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Many irrigators face the prospect that they will not be able to fully irrigate their crops. In these cases, they still need to schedule their water applications to make the best economic use of available water. Major scheduling questions for deficit irrigation include: (1) will preseason irrigation be beneficial; and (2) when should irrigation be started and stopped during the growing season. Traditional irrigation scheduling has been developed for irrigation systems that can supply the full irrigation requirements of the crop and produce maximum crop yields. Irrigation schedules are based on current crop water requirements and predict irrigation needs in the immediate future. Irrigators practicing deficit irrigation need to predict irrigation schedules in advance of the growing season and make appropriate adjustments based on potential crop yields and economic returns. A computerized decision tool, the Crop Yield Predictor (CYP) has been developed to predict yields from alternative irrigation schedules. The user determines soil water status before or during the cropping season and formulates a potential schedule of irrigation dates and amounts. Soil water holding capacity and irrigation system water delivery capacity are constraints on the ability to supply water to the crop. CYP uses a daily soil water balance coupled with computations of effective evapotranspiration (ETe) to predict crop yields from regional yield‐ET relationships. Multiple executions of CYP with alternative irrigation schedules lead to the schedules that project optimum net economic returns from the management scenarios.

Select this Article		The Arkansas Irrigation Scheduler Earl Vories, Phil Tacker, and Steve Hall ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)404 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the US Mid‐South, annual rainfall is generally sufficient for limited crop production, but periods of drought during the growing season make irrigation essential for optimum yields. However, factors such as cloudy weather, rainfall, and temperature swings caused by the movement of weather fronts all complicate irrigation scheduling. The Arkansas Irrigation Scheduler has been in use for over twenty years in Arkansas and surrounding states, with the current version released in 2008. The current version retains most of the objectives of the earlier versions, with the exception of being field‐, rather than system‐based, allowing users to view the soil water status of more of their fields at one time and group the fields as they feel most appropriate. Other changes made the program easier to learn, allowed the user to take advantage of more extensive weather data if it is available, and made the program applicable to more areas than before. Crop coefficient functions developed in the region are needed, but are not currently available. Future versions of the program may be limited to the internet, but no internet version is currently available for public use. In addition to improving yields, using the program to properly schedule irrigation can save energy and therefore money by reducing unnecessary pumping, and help to alleviate water shortages being experienced in many agricultural areas.

Select this Article		The Next Generation of Irrigation Management Programs P. M. Robinson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)405 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A number of states have developed advisory software to assist farm managers with irrigation scheduling. The fundamental procedures for irrigation scheduling are relatively straightforward and simple, but the diversity of the programs that have recently been developed is remarkable and significant. The range of analytical options offered by these programs is increasing; some have evolved from simple irrigation scheduling programs into comprehensive and sophisticated irrigation planning and management programs, driven in part by the accelerating competition for water. The next generation of irrigation management software will need to address the challenge of optimizing irrigation management; i.e. maximizing net economic returns rather than maximizing yields. But the software to do that is inherently very complex, and development of such software is beyond the resources of most individual states or agencies. This paper provides an overview of existing and developing irrigation management programs in the U.S. and suggests some potential components of the next generation of irrigation management software.

Select this Article		Woodruff Irrigation Charts J. C. Henggeler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)406 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Woodruff Irrigation chart method of irrigation scheduling began as a graphical chart solution of when to irrigate for a specific crop, location, planting date, and soil in Missouri. It has been expanded to a web‐based chart maker that can be used for corn, cotton, and soybeans in Missouri and adjacent states. Survey data indicates that irrigators who use the Woodruff charts increase their yields over non‐schedulers by 14.0 bu/ac more corn, 104 lbs/ac more cotton, and 10.7 more bu/ac soybeans. In southeast Missouri approximately 16%, 6%, and 5% of corn, cotton, and soybean irrigators use the Woody method, while 12%, 17%, and 7% use the Arkansas Scheduler. Total impact since 2001 is estimated to be $54 M.

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CURRENT IRRIGATION SCHEDULING ADVISORY SYSTEMS 2

Select this Article		A Web‐Based Advisory Service for Optimum Irrigation Management Charles Hillyer, Marshall English, Carole Abourached, Chadi Sayde, Kent Hutchinson, and John Busch ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)407 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The optimum (profit maximizing) level of irrigation water use is usually less than the yield maximizing level, particularly when water has an associated opportunity cost. However, the amount of analysis required to implement a profit maximizing strategy is usually too time consuming to be practical for most farmers. Furthermore the practical operational constraints imposed on typical irrigation practices are usually too complicated to be fully encapsulated in software. Oregon State University and the NRCS have cooperatively developed a web‐based, user‐directed application for optimum irrigation management. This system has already completed two years of field trails and has a demonstrated capacity for delivering conventional irrigation schedules. The system is now entering a second phase of development where we are adding new analytical tools that enable easy generation of optimum irrigation schedules. This system, known as Irrigation Management Online (IMO), explicitly analyzes irrigation efficiency and yield reductions for deficit irrigation, performs simultaneous, conjunctive scheduling for all fields in the farm that share a limited water supply, and employs both ET and soil moisture measurements in a Bayesian decision analysis to enhance the accuracy of the irrigation schedules. To mitigate the complexities of irrigation constraints the system has been designed so that the user is an integral part of the irrigation optimization procedure.

Select this Article		Estimating Crop Coefficients from Fraction of Ground Cover and Height Richard G. Allen and Luis S. Pereira ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)408 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The crop coefficient is the ratio of actual ET to reference ET and is heavily controlled by the amount of vegetation present to transpire water. This relationship can be used to estimate values for the crop coefficient as functions of the amount of ground covered by vegetation. A method established in the FAO‐56 publication is expanded in this paper to estimate the crop coefficient from the fraction of ground cover and height of vegetation. In addition, when estimates of average background soil evaporation are made, then the ‘mean’ or single crop coefficient can be estimated. Estimates from the method are compared with measured crop coefficients reported for a number of vegetable crops during the crop development periods. Results are promising.

Select this Article		Manure Application to Soybeans in the Chesapeake Bay Watershed William F. Ritter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)409 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Corn and soybeans are major crops grown in the Chesapeake Bay watershed. The watershed has significant numbers of poultry, dairy and swine in certain areas. Land application of manure is a standard practice in the watershed. Over the years phosphorus concentrations have built up in manure applied soils because application rates have been based upon crop nitrogen requirements. In some cases research has shown manure application will increase soybean yields. One of the environmental concerns of applying manure to soybeans is the risk of increasing nitrate concentrations in the groundwater or tile drainage. Another concern is the buildup of phosphorus in the soil, which may cause phosphorus leaching on sandy soils or increase phosphorus loads in surface runoff.

Select this Article		On‐Line Irrigation Scheduling within the Belle Fourche Irrigation District Jared K. Oswald and Hal D. Werner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)410 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract On‐line irrigation scheduling consultant software is being developed for producers within the Belle Fourche Irrigation District (BFID). This project, which is funded for 3 years by a Conservation Innovation Grant (CIG) through the Natural Resources Conservation Service (NRCS), is entering its second irrigation season. The BFID is a gravity‐fed, canal‐based system located in western South Dakota. Recurring droughts often limit the amount of water available for irrigation in the BFID. The purpose of this project is to provide producers with a reliable, easy‐to‐use means to monitor and schedule irrigations that will conserve water and reduce the amount of sediment‐laden irrigation return flows that are discharged into the adjacent Belle Fourche River, historically listed as impaired for total suspended solids (TSS) by the South Dakota Department of Environment and Natural Resources (SD DENR).

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DRAINAGE INFRASTRUCTURE AND NONPOINT SOURCES

Select this Article		Agricultural Drainage Management Systems Task Force (ADMSTF) James L. Fouss and Michael Sullivan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)411 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Agricultural Drainage Management Systems (ADMS) Task Force was initiated during a charter meeting in the fall of 2002 by dedicated professional employees of Federal, State, and Local Government Agencies and Universities. The Agricultural Drainage Management (ADM) Coalition was established in 2003 by drainage industry officials, trade associations and non‐government organizations. These two groups formed a working partnership to promote and implement drainage water management systems that can significantly improve the quality of drainage water flows from agricultural cropland. Earlier research had shown that a large percentage of the nitrate‐nitrogen that migrates down the Ohio and Mississippi Rivers comes from surface and subsurface drainage discharge from agricultural cropland in the Midwest region. An initial primary goal of the partnership groups was to reduce the loss and transport of fertilizer nutrients, particularly nitrate‐nitrogen, from drained agricultural croplands in the Midwestern States on a farm‐by‐farm basis. They installed and conducted field demonstrations for farmers to promote and encourage them to install and implement drainage water management practices (controlled‐drainage) for both new drainage installations and by retrofitting their existing drainage systems with drainage outlet controls. Previous research that had been conducted at multiple locations to evaluate controlled‐drainage systems documented that the decrease in nitrate‐nitrogen loss in drainage discharge was almost directly proportion to the reduction in drainage outflow volume accomplished by installing control structures on the drainage outlets. A 50% reduction in drainage outflow and nitrate loss was a common research finding at most of these locations. The desired ultimate goal of the ADMSTF and ADMC partnership efforts was to implement drainage water management on a large enough scale (watershed‐by‐watershed) in the Midwest to decrease transport of excess nutrients through the Mississippi River drainage basin to the Gulf of Mexico. EPA and USGS had reported this source of nitrate‐nitrogen as one of the major sources contributing to the persistent formation of the large hypoxic zone (“dead zone”) in the Gulf of Mexico.

Select this Article		Denitrifying Bioreactors for Treatment of Tile Drainage Laura E. Christianson, Alok Bhandari, Matthew H. Helmers, and Martin St. Clair ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)412 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Much of the hypoxia in the Gulf of Mexico has been attributed to agricultural nonpoint pollution sources in the Midwestern states. There is, therefore, a critical need to develop practical and cost effective methods to reduce nitrate loadings from these areas. As the hypoxic zone is thought to be larger this year than ever before, the time is ripe for new technologies to reduce nutrient loads in the Mississippi River. Denitrifying drainage bioreactors can provide cost‐effective treatment of tile water at the field scale while requiring minimal system maintenance. These bioreactors consist of a trench filled with an available carbon source (usually woodchips) that is readily colonized by bacteria and fungi capable of utilizing nitrate as an electron acceptor. A handful of such bioreactors have been installed in the US Midwest and have shown good nitrate removal. This poster describes the design, field installation, and cost estimates of full‐scale denitrifying bioreactors.

Select this Article		Drainage Main Rehabilitation in Iowa M. J. Helmers, S. Melvin, and D. Lemke ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)413 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Subsurface drainage systems installed throughout much of north central region of Iowa have provided substantial crop production benefits. However, most of these systems were installed in the early 1900's and as such they are reaching their design life. With the aging infrastructure of these systems, better economic conditions, and the potential for more financial gains for better drainage; there will need to be significant rehabilitation that occurs in the future. This paper will discuss some of what is known about the existing infrastructure in this area, some potential opportunities for future redesign, and potential economic returns of drainage district redesign. The future redesign would need to include environmental as well as economic considerations and might include the integration of drainage and wetland systems. While this paper focuses on a specific location, the concepts should have relevance to many areas where existing drainage infrastructure is aging.

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ET IN WATER RIGHTS AND WATER TRANSFERS 1

Select this Article		Alfalfa Reference ET from a Weighing Lysimeter and Estimates from the ASCE Standardized Reference ET Equation in the Arkansas Valley of Colorado Allan Andales, Dale Straw, Thomas Ley, and Abdel Berrada ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)414 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The American Society of Civil Engineers (ASCE) standardized reference ET equation has been prescribed for use in the Arkansas Valley of Colorado for estimation of reference evapotranspiration (ET) and subsequent estimation of crop consumptive use. In 2006, a precision weighing lysimeter (mechanical lever scale — load cell combination) was installed at Rocky Ford, Colorado to verify the performance and predictive accuracy of the ASCE standardized ET equation for calculating alfalfa reference (tall reference) ET values. The undisturbed soil monolith is contained in a tank that is 3 m × 3 m in area and 2.4 m deep. The standard deviation of the weight measurements was less than 0.02%, based on calibration of the load cell with known weights. Alfalfa was established on the lysimeter and surrounding field (4 ha) in 2007. Instrumentation for micrometeorological measurements as well as soil temperature, soil heat flux, and soil moisture measurements were installed. Calculated ET from the ASCE standardized equation (ET_rs) and ET measured from the lysimeter (ET_r) were compared during periods in the 2008 season when the alfalfa crop on the lysimeter and surrounding field were considered to be in reference conditions. Calculated ET_rs agreed well with ET_r from the lysimeter when wind conditions were relatively calm and vapor pressure was relatively stable. However, ET_rs tended to be greater than ET_r under advective conditions. Also, calculated ET_rs was notably less than ET_r from the lysimeter on a number of days late in the growing season. The underlying causes of these differences need further investigation.

Select this Article		ASCE Standardized Penman‐Monteith Alfalfa Reference ET and Crop ET Estimates for Arkansas River Compact Compliance in Colorado Thomas W. Ley, P.E., M. ASCE, Dale E. Straw, P.E., and Robert W. Hill, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)415 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the fourth report in the case of Kansas v. Colorado (No. 105, Original, U.S. Supreme Court), regarding compliance with the Arkansas River Compact, the Special Master hearing the case recommended specific changes by which Arkansas River streamflow depletions at the Colorado‐Kansas Stateline are determined. One of the major changes was the recommendation to move away from the modified Blaney‐Criddle method and adopt a reference crop evapotranspiration‐mean crop coefficient approach to determine crop consumptive use estimates for input to the computer model used to determine compact compliance. This paper discusses some of the steps the State of Colorado has taken to comply with this recommendation.

Select this Article		Interstate Collaboration in the Arkansas River Compact Compliance Process: The “Nuts and Bolts” of Developing PET for Canal Service Areas for Input to the H‐I Model Mary Kay Brengosz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)416 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Hydrological‐Institutional (H‐I) Model is a computer model used to determine compliance with the Arkansas River Compact. The States of Kansas and Colorado complete an annual update of the model to compute the effects of well pumping on Stateline river flows. The annual update process requires the two States to agree on the crop mix, weather data and potential evaporation (PET) estimates for the canal service areas (among other things). The H‐I Model is highly sensitive to the crop evapotranspiration input, so the update of this input data set is given particular attention by both States. This paper describes the evolution of the PET estimates over time, and the steps involved in the annual update process, emphasizing the collaboration and cooperation that occur in order to reach a final PET data set.

Select this Article		Overview of Development and Use of Crop ET Estimates with Hydrological Models for Interstate Compacts Dale E. Book and Mary Kay Brengosz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)417 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Crop Evapotranspiration (ET) is an important element in hydrological modeling in river basins with significant irrigation. The State of Kansas currently participates in ongoing modeling in two river basins for the purpose of monitoring compliance with interstate compacts: the Arkansas River in Colorado and Kansas and the Republican River in Kansas, Nebraska and Colorado. The decree in Kansas v. Colorado (No. 105, Original, U.S. Supreme Court) provides for annual updates of the Arkansas River Hydrological‐Institutional Model (H‐I Model) to compute the effects of well pumping and offsets on Usable Stateline flows. The model was originally developed for the litigation, and has been modified for use in monitoring compact compliance. The Republican River Groundwater Model was developed through negotiation as part of a settlement in the case of Kansas v. Nebraska & Colorado (No. 126 Original, U. S. Supreme Court). The Republican River model is used each year to determine the Calculated Beneficial Consumptive Use attributed to groundwater pumping in the Republican River Basin in the States of Nebraska, Colorado and Kansas. The settlement stipulation requires that each state calculate the crop irrigation requirement by county and compare those estimates to the pumping. This paper discusses the development and function of crop ET in each setting.

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ET IN WATER RIGHTS AND WATER TRANSFERS 2

Select this Article		Adjusting Wind Speed Measured over Variable Height Alfalfa for Use in the ASCE Standardized Penman‐Monteith Equation Thomas W. Ley, P.E., M. ASCE, Richard G. Allen, M. ASCE, and Marvin E. Jensen, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)418 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The ASCE Standardized Reference Evapotranspiration Equation expects the weather station wind speed data to represent that occurring at a height of 2 m over and downwind of a smooth measurement surface such as clipped grass. The Task Committee on the Standardized Equation provided guidance for adjusting wind speed measured at height other than 2 m, or, for situations when the wind speed is measured over and downwind of 0.5 m alfalfa. The latter adjustment attempts to account for the effects of both grass and alfalfa crop characteristics (height, roughness) on the wind profile. A more physically representative approach to adjust wind speeds at various heights and various weather measurement surface conditions to equivalent wind speed at 2 m height over clipped grass is tested. Wind speeds were simultaneously measured during the 2008 growing season at 2‐m and 3‐m heights above ground surface over variable height alfalfa at two Colorado Agricultural Meteorological Network (CoAgMet) electronic weather stations and at the research alfalfa lysimeter installation at the Colorado State University Arkansas Valley Research Center. These wind speed measurements were adjusted to estimated wind speed at 2 m over grass, and compared.

Select this Article		Estimation of Evaporation and Evapotranspiration during Nongrowing Seasons Using a Dual Crop Coefficient Richard G. Allen and James L. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)419 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Evapotranspiration and net irrigation water requirement estimates were updated in 2007 by Allen and Robison (2007; Allen et al., 2007) for agricultural areas in Idaho. ET calculation procedures were employed that use an updated procedure to calculate crop coefficients that considers the impact of surface wetting by irrigation and precipitation on total evapotranspiration. ET was calculated for daily, monthly and annual timesteps for 123 weather station locations across Idaho for complete, available periods of record. ET estimates were made for all times during the calendar year including winter to provide design and operation information for managing land application of agriculture, food processing and other waste streams and to provide full‐calendar year estimates of E and ET for hydrologic studies and to estimate beginning of growing season soil water content.

Select this Article		Evapotranspiration and Net Irrigation Water Requirements for Nevada J. L. Huntington and R. G. Allen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)420 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Evapotranspiration (ET) of water is a primary component of the hydrologic cycle and is becoming more significant as increasing demands are placed on finite water supplies in Nevada and across the western U.S. Local, state, and federal water resource agencies have a great need for accurate estimates of net irrigation water requirements for evaluating irrigation development, transfers of irrigation water for municipal use, and litigation of water rights applications and protests. The major objective of this study is to update estimates of crop ET and net irrigation water requirements for Nevada. Estimates of ET and net irrigation water requirements are made for all major crops grown in Nevada at over 200 locations using National Weather Service weather stations located throughout the state. The methods for estimating ET follow the new ASCE‐EWRI Standardized Penman‐Monteith approach, while the net irrigation water requirement for crops is estimated using a dual crop coefficient and daily soil water balance approach. Results show that in central and northern parts of Nevada, the net irrigation water requirement for alfalfa, the primary crop grow in Nevada, is less than the typical permitted amount of irrigation water rights of 4 ac‐ft/ac, indicating that if irrigators wish to change or sell their water rights to more consumptive uses, they would not be able to transfer the entire water right. These revised estimates of ET and net irrigation water requirements for various crops will be used for updating basins water budgets and establish the amount of irrigation water that is available for water transfers in the future.

Select this Article		Integrated Water Management in an Ancestral Water Scheme in a Mountainous Area of Southern Spain G. Vivas, E. Gómez‐Landesa, L. Mateos, and J. V. Giráldez ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)421 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The snow pack of Sierra Nevada, Southern Spain, melts during spring and early summer feeding ancestral irrigation canals in the region called Alpujarra. This study compared the traditional supply, based on proportional division, with the actual supply, based on up‐downstream priority, in a representative watershed in the Alpujarra. A combination of three models was used for the analysis. Snow melt and runoff were simulated using the Snow Runoff Model and satellite images to determine snow cover. A second model (based on a water balance with capacity constraints) simulated the distribution of water either following proportional supply or up‐downstream priority. Crop irrigation requirements were simulated using the FAO approach. The equity inherent to the proportional supply did not diminish adequacy overall. Because of the reuse of return flows in the watershed, irrigation efficiency at the watershed scale was significantly greater than irrigation efficiency at the irrigation canal scale.

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ET MEASUREMENT AND CALCULATION

Select this Article		Comparison of Sensible Heat Flux Measurements by a Large Aperture Scintillometer and Eddy Correlation Methods Xinhua Jia, Xiaodong Zhang, and Dean D. Steele ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)422 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The eddy correlation (EC) method has been recommended as one of the standard methods for measuring actual evapotranspiration. One of the challenges in interpreting eddy correlation measurements is that the balance between various energy components measured and the total energy received can sometimes be off by up to 30%. An independent measurement of sensible heat flux by scintillometry is often used to resolve this energy balance closure problem. An EC system was set up at a 47 ha commercial corn field in southeastern North Dakota in 2008. Net radiation, latent heat flux, sensible heat flux, soil heat flux and other weather parameters were measured continuously at a 30‐min interval during the growing season. A Scintec Boundary Layer Scintillometer 900 (BLS900) was temporarily deployed for seven days when clear sky conditions were satisfied. During the synchronous experiment, both systems were adjusted to at least 1 m above the canopy and collected data at an increased frequency of every minute. The EC system was placed at approximately the midpoint of the scintillometer path. The comparison of sensible heat fluxes measured by the two methods showed good agreement. The results will be used to validate the eddy correlation system in an attempt to reconcile the closure of energy balance.

Select this Article		Mid‐Summer Deficit Irrigation of Alfalfa as a Strategy for Saving Water B. R. Hanson, K. M. Bali, S. B. Orloff, B. L. Sanden, and D. Putnam ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)423 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Evapotranspiration (ET) of fully‐irrigated and deficit‐irrigated (no irrigation in July, August, and September) was measured in five alfalfa fields at various locations throughout California. Seasonal ET ranged from 838 to 1,651 mm, which differed from historical seasonal ET. Deficit irrigation reduced ET, but the ET difference between fully‐irrigated and deficit‐irrigated alfalfa was site specific. Yields were reduced by deficit irrigation.

Select this Article		Recursive and Explicit Combination Methods for Calculating Reference Evapotranspiration C. H. Hay and S. Irmak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)424 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Efficient use of water in agroecosystems requires the accurate quantification of evapotranspiration (ET). Explicit combination method (ECM) equations (i.e., the Penman equation and its derivatives) have been widely used and tested. These equations rely on an assumption to remove the surface temperature from the calculation, and the validity of this assumption has been questioned as likely underestimating ET, particularly in semiarid and arid climates. Information on the validity of this assumption in subhumid regions is rare. Recursive combination methods (RCM), based on an equation proposed by Budyko, make no assumptions for the surface temperature, but they require iteration to arrive at a solution. The objective of this research was to compare daily ET calculated by the ECM and RCM and compare those values to Bowen ratio energy balance system (BREBS)‐measured ET for a well‐watered and maintained grassland near Central City, Nebraska. The results indicated that both equations were sensitive to the value chosen for the surface resistance (r_s). For equivalent values of r_s, ET predicted by the ECM was greater than ET predicted from the RCM. Using r_s values of 40 s m⁻¹ for the ECM and 20 s m⁻¹ for the RCM resulted in the best predictive performance for the two methods, and using these values, the ECM performed slightly better. While the RCM may potentially provide more accuracy under some conditions, it was no more accurate than the ECM under these experimental conditions.

Select this Article		Some Results of Evapotranspiration Measured by Three Weighing Lysimeters in La Mancha, Spain R. López‐Urrea, A. Montoro, P. López‐Fuster, and F. Martín de Santa Olalla ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)425 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In semiarid environments with a shortage of water resources and a risk of overexplotation, it is essential to improve the accuracy of the estimation of crop water requirements to reduce water use and increase water productivity. For this reason, in 1999 three weighing lysimeters were installed in the experimental farm “Las Tiesas” located in Albacete (Central Spain). The facility has a lysimeter for measuring the grass reference evapotranspiration (ET_o), a second for rotating annual crops and third installed in a perennial vineyard for measuring grape water use. Each of lysimeter is surrounded by a one hectare square buffer plot planted to the lysimeter crop. The lysimeters are weighed with a balance beam and load cell configuration, with most of the weight being eliminated using counterweight. The overall resolution of the systems are 250 g or 0.04 mm of water. The measurement frequency is one second, and a reading is registered by a datalogger every 15 min. During the period 2002–2003 the FAO‐56 Penman‐Monteith (FAO‐56 PM) and the ASCE “standardized” version of Penman‐Monteith (ASCE PM) hourly equations were evaluated by comparing them with reference lysimeter measurements. In 2003 we measured the water use (ETc) of broccoli as a double crop. Records of grapevine ET were collected from 2002 to 2008 and detailed canopy development information was obtained from 2004 to 2008 growing seasons. In this paper, we present results of grapevine ET measured by a weighing lysimeter during 2008 growing season.

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IRRIGATION AND DRAINAGE ISSUES

Select this Article		Application of SIRMOD to Evaluate Potential Tailwater Reduction from Improved Irrigation Management Byron Clark, Lindsay Hall, Grant Davids, Wynn Walker, and John Eckhardt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)426 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The SIRMOD surface irrigation simulation, evaluation, and design software developed at Utah State University was applied to evaluate potential increases to irrigation performance from improved irrigation management within the Imperial Irrigation District of Southern California (IID). This study was conducted as part of a planning effort to develop strategies to satisfy the Colorado River Quantification Settlement Agreement and Related Agreements (QSA), which call for IID to generate more than 300,000 acre‐feet annually through a combination of District and voluntary on‐farm efficiency conservation savings. Potential irrigation management performance increases were evaluated by calibrating the SIRMOD model for 34 selected border and furrow irrigation events for which delivery and tailwater hydrographs were measured. These events occurred at fields distributed throughout the Valley representing a range of crops, soils, run lengths, and tailwater production (surface runoff). For each event, simulations were conducted to identify potential reductions in tailwater resulting from different combinations of inflow rate and cutoff time. Simulations were constrained to minimize reductions in irrigation adequacy. Simulation results were detuned to represent practical, attainable performance based on an estimate of uncertainty in the soil moisture deficit prior to irrigation on the planning of an irrigation delivery.

Select this Article		Evaluation of Magnetic Meters for Irrigation Pipeline Measurement Stuart W. Styles and Bryan Busch ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)427 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Magnetic flow meters are used to measure the flow rate of a liquid in a closed pipeline. This type of meter is becoming increasingly popular for measurement with agriculture applications. Electromagnetic meters were tested by the Irrigation Training and Research Center in pipelines located less than the 10 diameters upstream of disturbances with good results. Results show that location guidelines for placing a magnetic meter can be decreased even for turbulent conditions. This paper will discuss how a magnetic flow meter works, advantages and disadvantages of this type of meter, test results, and new guidelines for field applications.

Select this Article		Increasing Field Work Productivity in Irrigation Evaluation Processes through the Use of Combined Irrigation Models Sergio Lecina, Christopher M. U. Neale, Gary P. Merkley, and Carlos A. C. dos Santos ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)428 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A surface irrigation evaluation process in an irrigation project requires expensive field work. Models that reproduce irrigation events help to analyse the data obtained, and evaluate different scenarios of improvement. The use of combined models that reproduce the interaction between irrigation water and the conveyance and drainage network, agricultural production, and the environment can increase the productivity of the field work. Their results surpass the analyses based only on application efficiency, and provide a wide range of irrigation, hydrological and economic indicators. The application of one of these models (Ador‐Simulation) in a study area of the Bear River irrigation project (UT) showed that an increase in irrigation efficiency from 56 to 77 % can be achieved optimizing current irrigation time. This results in a 27 % of water saving over the 2008 demand, and in a little increase in current low economic productivities.

Select this Article		Neighborhood Channel Is Redefined with Boulder Armoring Ted Niemann, P.E., D.WRE and John Loechle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)429 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A channel through a neighborhood in Jefferson County, Kentucky was eroding and accumulating complaints of property damage and flooding. The channel, carrying an intermittent stream, had been filled by the developer of this neighborhood to be a grass channel flowing through the backyards. Development upstream increased the flows through this area and caused erosion of the grass channel. Efforts to armor the channel with gabion baskets and rip rap, and in some cases landscape timbers did not stem the tide of damage. The length of channel being evaluated was approximately 1,800 feet. A solution for the entire length under review was desired. Armoring the banks with boulders was the preferred method to stabilize the stream banks. The SCS TR‐55 program was utilized to calculate flows to size the proposed channel. The channel width was chosen to allow the channel to achieve bank full depth. The bank full depth was determined by field observation of sections of the entire length of the existing stream. The proposed channel alignment was arranged to closely resemble the existing and to minimize disruption to existing utilities as well as uses by the adjacent property owners. Methodology of the hydraulic analysis and design of the stream bank armoring is discussed herein as a low tech solution for urban and suburban stream projects. Armoring the stream banks provided the protection needed while defining the stream and allowing movement of runoff through the project area without using a concrete channel. The use of boulders along the banks created a more “natural” channel appearance and satisfied the client (MSD) as well as the adjacent property owners.

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LANDSCAPE IRRIGATION SCHEDULING AND WATER MANAGEMENT

Select this Article		Evaluation of Irrigation Scheduling Efficiency and Adequacy by Various Control Technologies Compared to Theoretical Irrigation Requirement Mary McCready and Michael D. Dukes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)430 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A variety of commercially available technologies for reducing residential irrigation water use are available to homeowners. These technologies include soil moisture sensors, rain sensors and evapotranspiration (ET) based controllers. The purpose of this research was to evaluate the effectiveness of these various technologies comparing the adequacy and efficiency of the irrigation schedules for each control device with an irrigation schedule developed using a theoretical soil water balance. Testing was performed on a soil moisture sensor (SMS, LawnLogic) at a low and a medium soil moisture threshold setting. Mini‐Clik rain sensors (RS) comprised four treatments, with one treatment pre‐set for 3 mm of rainfall and an irrigation frequency of 7 d/wk. The other three RS treatments had sensors pre‐set to bypass irrigation for 6 mm of rainfall and irrigation schedules of either 1 or 2 d/wk. An ET controller was also tested, the Toro Intelli‐Sense controller (TORO). A time‐based treatment with irrigation 2 d/wk and no rain sensor (WOS) was established as a comparison. In general the irrigation schedule for all treatments was more adequate during the fall months of testing than the spring months. Efficiency decreased for most treatments in the fall months of testing. Adequacy values calculated for 30‐day running totals tended to vary greatly during a testing period. During the spring months of testing the average range in 30‐day adequacy ratings was 24% and during the fall months the average range was 21%. The range in adequacy was as high as 63% during testing for one treatment. Looking at only one 30‐day testing period may not fully capture the adequacy of an irrigation control device.

Select this Article		Irrigation Rain Sensors Accuracy B. Cardenas‐Lailhacar, M. D. Dukes, P.E., and L. Meaks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)431 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In recent years, an increasing number of municipalities throughout the country have implemented mandates, rebates and/or cost‐saving programs for the use of rain sensors (RSs). The objectives of this research were to evaluate two expanding disk RS types, Mini‐Click (MC) and Wireless Rain‐Click (WL), with respect to: a) the accuracy of their set point with respect to rainfall depth, b) the number of times in irrigation bypass mode, and c) the duration in irrigation bypass mode. For the MC treatments, rainfall set points of 3, 6, and 13 mm were established. Rain sensor models were monitored from 1 January 2006 to 31 July 2007, except for MC set at 6 mm which was monitored starting on 13 September 2006. The 576‐day experimental period had rainfall frequency and cumulative amount below a historical year. The number of times that replicate units within a treatment switched to bypass mode tended to behave the same through time, for treatments WL and 3‐MC, which ranged from 64 to 78 events and from 57 to 68 events, respectively. Treatment 6‐MC was the most consistent between replicates, where three units switched to bypass mode on 39 occasions, and one unit did it on 34 times. Replicates from treatment 13‐MC showed the most variable behavior, shutting off between 50 to 29 times. On average, treatment WL shut off after 2.8 mm of rain. Because this model does not have a specific set point, accuracy could not be calculated. Accuracies for the other treatments resulted in 73% for 3‐MC, 30% for 6‐MC, and 58% for 13‐MC. Treatments WL, 3‐MC, 6‐MC, and 13‐MC, remained in bypass mode 82, 80, 64, and 83% of the time, respectively, for less than 24 h.

Select this Article		Preliminary Results for Bench Testing of Evapotranspiration‐Based Irrigation Controllers in Florida Stacia L. Davis and Michael D. Dukes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)432 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Irrigation Association has developed a smart water application technologies (SWAT) testing protocol for ET controllers that describes a procedure for testing the efficacy of ET controllers. The test requirements include a minimum of thirty consecutive days with 63.5 mm of reference evapotranspiration (ET_o) and 10.2 mm of rainfall. The objectives of this study are to duplicate the soil water balance calculations specified by the SWAT test and recreate the SWAT bench test in a humid region using ET controllers previously tested under the SWAT protocol in an arid climate. Three brands of ET controllers previously tested under the SWAT protocol by CIT were installed at the Agricultural and Biological Engineering campus research facility (Gainesville, FL). The controllers are as follows: Weathermatic SL1600 with SLW20 weather monitor, Toro Intelli‐sense duplicates utilizing the WeatherTRAK ET Everywhere Service, and ETwater Smart Controller 100 duplicates. Duplicate controllers were distinguished by whether they utilized an additional Mini‐clik rain sensor denoted with a rain sensor (WRS) or without a rain sensor (WORS). The study period for each controller received less ET_o and rainfall compared to historical averages by 40% and 56%, respectively. The results found during the 2008 SWAT test showed that the ET controllers generally scored well in SWAT performance scores of scheduling efficiency and irrigation adequacy. However, the controllers resulted in lower scheduling efficiency scores than the original published results: 2.5% for the ETwater controllers, 14% by the Toro controllers, and 5.6% by the Weathermatic. It is likely that manufacturers would have opted to not publish these results as a SWAT score and restarted the test with minor adjustments. The SWAT test determines whether the controllers have accurate irrigation scheduling capabilities and does not rate the potential for a controller to conserve water. The SWAT testing protocol should be clearly outlined and detailed enough for results to be reproducible if it will continue to be used as an industry standard.

Select this Article		The Use of Soil‐Water Sensors in Turf Irrigation Control‐How Effective Are They? Garry L.Grabow, Michael Dukes, and Bir Thapa ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)433 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Soil‐Water sensor controllers have been used since the mid‐1990s to manage turf irrigation. While evapotranspriation (ET) based controllers have been more widely adopted for turf and landscape irrigation, soil‐water‐sensor based systems hold some distinct advantages, particularly in humid regions where rainfall contributes significantly to turf water requirements and is highly spatially variable. Some perceived disadvantages of soil‐water‐sensor based systems are representativeness of whole landscapes when only one sensor is used; sensor accuracy and repeatability, and proper setting of soil‐water setpoints. Several studies involving soil‐moisture sensors have been done in Florida, and one study in North Carolina is near completion. These studies have looked at soil‐water sensor based systems of various manufacturers in similar settings; have compared results between different moisture setting thresholds; have contrasted water usage with ET based controller systems; and have monitored root zone soil‐water status in plots irrigated by soil‐water based systems. Soil‐water data has also been collected for replicates of sensor‐based treatments in an effort to address the question of repeatability and sensor placement representativeness. Preliminary data from these studies have shown that there is wide variability between different sensor systems with respect to both applied water and turf quality. The data has also shown that soil water sensor based systems may in some cases apply less water than ET controllers. Consistent relationships between soil‐water‐content and controller settings has been found to be problematic. Analysis of soil‐water data indicates that while there are differences in soil‐water between replications of soil‐water‐based sensor treatments, soil‐water trends are generally consistent between replications and turf quality is generally not substantially different between replications.

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EVAPOTRANSPIRATION

Select this Article		Application of SVMs Algorithms for Prediction of Evaporation in Reservoirs Arun Goel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)434 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Assessment of water resource requires effective procedures for evaporation estimation involving measurable meteorological parameters and such approaches are rarely available in the literature. In the present work, the data of daily evaporation, temperature, solar radiation, relative humidity, wind speed are used to assess the potential and usefulness of SVM based modeling. The performance of the SVM algorithms (Rbf & Polynomial) is compared with the linear regression on the basis of performance parameters having different combinations of input parameters. The comparison of results showed that there is better agreement when more input parameters are considered for model building as compared to a single parameter. The outcome of study suggests that the SVM based modeling can be applied as an alternative approach for estimation of daily evaporation from the reservoirs.

Select this Article		Controlled Drainage Effects on Crop Yield and Water Use Efficiency under Semi‐Arid Condition of Iran Negar Sharifi Mood, Masoud Parsinejad, and Farhad Mirzaei ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)435 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Control of water table is one of the management processes in irrigation and drainage networks to reduce nitrogen, other salts and drainage water. Suitable depth of water table is decided upon based on the balance between effective root depth, capillary zone and upward flow. In addition sensitivity to water logging, soil water storage capacity, and electrical conductivity of irrigation water and soil stratification should also be taken into account. if saline irrigation water is used, as a result of water loss through evaporation a salt stratification will result with the soil surface being more saline because of gradual accumulation of salts. The main effect of soluble salts on plants is osmosis effect because the presence of salts, adequate water absorption would be difficult for plants. This study was conducted to examine the feasibility of implementing water table control technique (i.e., controlled drainage) in an arid and semi‐arid region (e.g., Iran) with particular attention to its salinity management. Two water table control treatments including: free drainage (FD) and controlled drainage (CD) with 40 cm controlled water table and three different irrigation water salinity namely: 0.75, 3.4 and 4.8 dS/m were considered. The experimental setup included 6 treatments and three replications. Treatments were applied in 18 lysimeters (90 cm height, 55 cm diameter). The crop cultivated in lysimeters was sorghum. The results indicated that CD method can be used in arid and semi arid regions. The evidence showed that yield of the CD treatment is 2.5 times higher than FD treatment.

Select this Article		Estimation of Regional Reference Evapotranspiration from Land Surface Temperature and Co‐Kriging Method at Tehran Province, Iran Mahdi Shahabifar, Maryam Chaichi, and Mahdi Kouchakzadeh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)436 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Evapotranspiration is the main factor of water cycle in nature and having the information of the amount of that is necessary to soil and water study. Estimation of this amount by using available equations indicates only the amount of evapotranspiration at the stations. Whereas in order to expansion water resources for irrigation and drainage, regional scale studied are required which geostatistical tools are used for achieving that. In this study reference evapotranspiration at 31 meteorology stations in Tehran province with Hargreaves‐Samani method in January (wet) and July (dry) were estimated. To supply reference evapotranspiration maps in province that capable to be used at regional study, Co‐Kriging was used. Land surface temperature was covariate in this method and has been determined by using image of NOAA14–16 at (1999–2003) and spilit window algorithms. Estimated temperature of images was compared with the temperature of 5cm depth of soil and Mean Absolute Error (MAE) was criterion for algorithms evaluation. Then land surface temperatures were determined from the network with 9200×7500m distance at area and were used for covariate of co‐Kriging method and the maps of monthly reference evapotranspiration were drawn.

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REMOTE SENSING OF ET 1

Select this Article		Comparison of Evapotranspiration Estimates from Remote Sensing (SEBAL), Water Balance, and Crop Coefficient Approaches Bryan Thoreson, Ph.D., P.E., M. ASCE, Byron Clark, P.E., M. ASCE, Richard Soppe, Ph.D., Andy Keller, Ph.D., P.E., M. ASCE, Wim Bastiaanssen, Ph.D., and John Eckhardt, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)437 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Three independent approaches were applied to estimate annual evapotranspiration (ET) for the Imperial Irrigation District of Southern California for the 1998 water year (October 1997 to September 1998). These approaches included remote sensing (Surface Energy Balance Algorithm for Land, SEBAL®), a district‐wide water balance with ET as the closure term, and a dual crop coefficient approach based on the procedures of FAO Irrigation and Drainage Paper No. 56 with refinements to account for field‐specific irrigation frequency. Differences between annual ET from each independent ET estimation approach are evaluated relative to estimated confidence intervals.

Select this Article		Independent Comparisons among Calibration and Output of Energy Balance Components Estimated by the METRIC Procedure J. H. Kjaersgaard, M. ASCE, P. H. Gowda, M. ASCE, R. G. Allen, M. ASCE, and T. A. Howell, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)438 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract An accurate estimation of evapotranspiration (ET) is an integral part of the hydrological cycle and is increasingly important in local and regional water resource management in central and western United States. Traditionally, estimation of ET included substantial uncertainties, but with the advent of algorithms applied to high resolution (30 m) satellite imagery, ET estimates from bare soil and vegetation can be obtained with greater accuracy. The METRIC image processing model estimates net radiation, soil heat flux and sensible heat flux through a series of steps before estimating ET as the residual from the energy balance. This paper describes a comparison of the METRIC surface energy balance model outputs produced by two different research groups when using the same two 2007 Landsat 5 images as input. One of the research groups is based at the USDA Conservation and Production Research Laboratory in Bushland, Texas where the images and ground‐based data were captured, and the other group is from the Kimberly Research Center, University of Idaho where METRIC was developed.

Select this Article		Measuring Soil Moisture in a Heterogeneous Field Chadi Sayde, John Selker, and Marshall English ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)439 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper explores the theoretical basis, preliminary experimental results and potential benefits of using fiber optic technology for distributed measurement of field soil moisture. This technology determines soil moisture content by measurement of soil thermal response to a heat pulse. With a resolution of 1 m along a fiber optic cable this technique is capable of literally hundreds of measurements along a single cable installed at a specific depth. The technology is still under development at the time of this writing, but the indications are that it can quantify soil water variability with relatively high accuracy at moderate cost.

Select this Article		Performance Evaluation of Soil Heat Flux Models in Great Plains R. K. Singh, A. Irmak, E. A. Walter‐Shea, and S. B. Verma ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)440 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Soil heat flux plays an important role in land surface energy dynamics by constraining the amount of available energy for partitioning between latent heat flux and sensible heat flux. Thus accurate quantification of the soil heat flux is of key importance in energy balance studies. In this study, the performances of four different methods have been evaluated for the soil heat flux estimation in maize and soybean fields under irrigated and dryland conditions. Statistical analysis of the model performance has shown a wide variation in the ability of these models from site to site and from year to year. The RMSE for irrigated maize ranged from 15.16 W m⁻² to 81.25 W m⁻², whereas the range for dryland maize was 14.99 W m⁻² to 55.81 W m⁻². The RMSE between predicted and measured soil heat flux for irrigated soybean was between 19.36 W m⁻² and 50.83 W m⁻². Relatively a narrow range (18.45–35.24 W m⁻²) of RMSE was found for dryland soybean. In view of wide range of RMSE and negative model efficiency, it is recommended that the local calibration of the model should be carried out for remote estimation of soil heat flux.

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REMOTE SENSING OF ET 2

Select this Article		Application of Remote Sensing Based Tillage Mapping Technique to Evaluate Water Quality Impacts of Tillage Management Decisions in Upper White River Basin Shashank Singh, Indrajeet Chaubey, and Prasanna H. Gowda ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)441 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Tillage practices directly impact runoff processes, erosion and water quality in agricultural watersheds. Consequently, environment models require tillage information for water quality modeling but often this information is not available at required spatial and temporal scales. Remote sensing approach facilitates tillage mapping at a larger scale than the conventional surveying methods. Models based on remote sensing can classify contrasting tillage practices with accuracy of 80% to 92%. The objectives of this study were to use reflectance based logistic regression models to classify contrasting tillage practices in agricultural watersheds using Landsat imagery. This study is conducted in the Upper White River Basin (7,000 km²) located in central Indiana, an agricultural watershed with corn‐soybean rotation. A single tillage practice can have different level of impact at different slope classes within the watershed therefore; the tillage system information is coupled with the slope classes within a watershed using geographic information system (GIS). This can identify the optimum slope class for a tillage system for minimum sediment loss. The tillage data derived are input in the Soil and Water Assessment Tool (SWAT) model to evaluate the distribution of tillage practices and their impacts on runoff, sediment, and pollutant losses.

Select this Article		Automated Selection of Anchor Pixels for Landsat Based Evapotranspiration Estimation J. H. Kjaersgaard, M. ASCE, R. G. Allen, M. ASCE, M. Garcia, W. Kramber, and R. Trezza ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)442 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract When managing local and regional water resources, the estimation of evapotranspiration is important and has generally been one of the components of the hydrological cycle that has the greatest uncertainty. With the development of suitable models and algorithms applied to high resolution (30 m) satellite imagery, evapotranspiration may be estimated with greater accuracy, and in a cost effective and time efficient manner. The METRIC image processing procedure calculates net radiation, soil heat flux and sensible heat flux through a number of steps before estimating evapotranspiration as the residual from the energy balance. Sensible heat flux is calibrated using the so‐called “cold” and “hot” anchor pixels. These pixels are selected by the user, which may introduce some operator dependency or human errors on the estimation of sensible heat flux and subsequently error in the final map of evapotranspiration. A procedure for automated selection of the anchor pixels is presented. The automated pixel selection procedure will reduce the user dependency of the estimations of sensible heat flux. Additionally, it may allow more novice users to obtain good results when applying METRIC.

Select this Article		Mapping ET at High Resolution in an Advective Semi‐Arid Environment with Airborne Multispectral Imagery J. L. Chávez, Ph.D., A. M. ASCE, P. H. Gowda, Ph.D., A. M. ASCE, T. A. Howell, Ph.D., F. ASCE, L. A. Garcia, Ph.D., A. M. ASCE, and K. S. Copeland ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)443 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Periodic and accurate estimates of spatially distributed evapotranspiration (ET) are essential for managing water in irrigated regions and in hydrologic modeling. In this study, METRIC (Mapping ET at high Resolutions with Internal Calibration), an energy balance algorithm originally developed for application with Landsat imagery at a regional scale, was applied to very high resolution aircraft imagery (0.5–2 m pixels) in the Texas High Plains. ET predictions were evaluated using data from four large precision weighing lysimeters located in the USDA‐ARS Conservation and Production Research Laboratory, Bushland, Texas. Statistical results indicated that METRIC worked better for crops with leaf area index greater than 2.5 m² m⁻². Potential limitations may have been the areal extent of the imagery, the surface roughness for the momentum transfer sub‐model, and the lack of a cold pixel with characteristics similar to the reference crop, i.e. alfalfa.

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LOCAL ISSUES—KANSAS CITY REGIONAL TOPICS

Select this Article		Brentwood Stream Restoration Project Lenexa, Kansas Anthony Hall, P.E. and Tom A. Jacobs, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)444 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Lenexa, Kansas (City) is a growing suburban community located in the Kansas City Metropolitan area. As with many growing communities, the City is regularly faced with various stormwater management challenges, including flooding, erosion, water quality impacts, regulatory requirements, and the ability to finance infrastructure improvements and new programs. To address these challenging issues, the City formed the Rain‐to‐Recreation Program. The Rain to Recreation program is a proactive, integrated, watershed based approach to address stormwater quantity and quality. The goals of the program are to reduce flooding, protect water quality and natural habitat, and provide recreational and education opportunities. With the implementation of new development regulations, the City has created greenways and trails while protecting the environment and preserving wildlife. The long‐term success of the program relies upon the support of individuals and businesses throughout the community. As such, the City builds community support through environmental education, and working together with local residents. Working together with the community, the program enhances the quality of the natural and built environments, ultimately conserving and even restoring our natural resources. One of the recent challenges addressed by the City involves the flooding and severe erosion problems along the Brentwood stream, which is located in a fully urbanized residential watershed. The following paragraphs describe the project background and challenges associated with this stream reach.

Select this Article		Golden Eagle — Brown County, Kansas Emergency Streambank Stabilization James M. Alexander ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)445 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Kickapoo Water Intake Structure on the Delaware River is located on the Kickapoo Reservation in southern Brown County, Kansas, approximately 6 miles west of Horton, Kansas, and 1/2 mile south of Kansas 20. It is in section 32 of Township 4 South, Range 16 East. This paper addresses bank instability problems in the vicinity of a water intake structure owned/operated/maintained by the Kickapoo Tribe of Kansas. Eroding left and right banks around the concrete weir structure have undergone previous attempts at stabilization. Previous repairs have not performed successfully. Erosion has continued, both in the area that had been protected by previous revetments immediately downstream of the weir, and along both banks for approximately 200 feet farther downstream. Bank erosion continues to threaten the stability of the structure, water supply lines, and the access road to the site. The purpose of this paper is to assess the instability problems, provide and compare conceptual alternatives with respect to feasibility, and make a recommendation as to the preferred alternative to accomplish the repairs.

Select this Article		Hutchinson, KS — 4^th and Carey Groundwater Remediation and Reverse Osmosis Water Treatment Facility Project Danita S. Boettner, P.E., Don Koci, P.G., Darren L. Brown, P.G., and Bruce Allman, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)446 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the early 1980s, the 4^th and Carey groundwater contamination site was discovered when the U.S. Environmental Protection Agency (EPA) began testing public water supply wells. A city of Hutchinson well located at the intersection of 4^th Avenue and Carey Street was found to be contaminated with volatile organic compounds (VOCs). The groundwater contamination findings issued as a result of EPA and Kansas Department of Health and Environment (KDHE) investigations led to the establishment of the 4^th and Carey Site. Strong proactive efforts by the city and local industry leaders prevented the site from being placed on EPA's National Priority List (NPL, or Superfund). The city signed a consent agreement with KDHE in 1994, assuming responsibility to clean up the site. At that time, the city contracted with CDM for remedial assistance. Impacts by high chloride levels in groundwater areas to be treated left the city faced with discharge restrictions due to total maximum daily load requirements for chloride in Cow Creek. The city evaluated alternatives that included beneficial reuse of contaminated water, including a regional solution that addressed the site's contamination, the high chloride waters, water appropriation issues, and other industrial groundwater contamination in the area. Implementation of the approved regional plan included the following activities: delineation of soil and groundwater contamination; installation of source area air sparge and soil vapor extraction systems; soil excavation; installation of a groundwater remediation well system for downgradient capture of regional contamination; water appropriations permitting; two Class I non‐hazardous underground injection control (UIC) wells; and construction of a fully automated 6‐million‐gallon‐per‐day (mgd) reverse osmosis (RO) water treatment facility. The facility blends treated water with 4 mgd of existing municipal water, producing 10 mgd of higher quality water for potable water use. The RO water treatment facility design and construction management was performed by Professional Engineering Consultants, P.A. (PEC).

Select this Article		Hutchinson, KS — 4^th and Carey Site Groundwater and Source Control Measures at Two Grain Elevators Darren L. Brown, P.G, Danita S. Boettner, P.E., and Don Koci, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)447 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The 4^th and Carey Site, U.S. Environmental Protection Agency (EPA) Identification Number KSD061608006, is located in Hutchinson, Kansas in Reno County. The site encompasses approximately 1,240 acres. Groundwater contamination at the site was discovered in the early 1980s when the EPA and Kansas Department of Health and Environment (KDHE) began testing public water supply wells. A city of Hutchinson well, located at the intersection of 4th Avenue and Carey Street, was found to be contaminated with volatile organic compounds (VOCs). The groundwater contamination findings conducted by EPA and the KDHE led to the establishment of the 4^th and Carey site in 1994 with the city of Hutchinson assuming the lead role in order to keep the site from being placed on EPA's National Priority List (Superfund). Agreements were reached with potential responsible parties (PRPs) for the contamination. Investigations at the site conducted by CDM for the city resulted in the identification of six carbon tetrachloride (CT) source areas; one trichloroethene (TCE) source area; one tetrachloroethene (PCE) and TCE source area; and two areas impacted by petroleum hydrocarbons. The TCE and PCE/TCE source areas are being addressed by the property owners under KDHE oversight. The areas impacted by petroleum hydrocarbons and one of the CT source areas are being monitored by the city. The remaining CT source areas required the implementation of source control measures for CT and its degradation products, primarily chloroform (CFM).

Select this Article		Impacts of Biota on Bioretention Cell Performance during Establishment in the Midwest A. M. Greene, S. L. Hutchinson, R. Christianson, and T. L. Moore ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)448 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract To understand the region‐specific effects of biota on function of bioretention cells, a lysimeter study was conducted at Kansas State University to determine how earthworms and native Kansas grasses impact runoff treatment and hydraulic function of a bioretention cell. This study also employed the Comprehensive Bioretention Cell (BRC) model to demonstrate how three seasons of growth could impact bioretention cell function. The model results of the first season of growth were then compared to field data. Results indicate that the interaction of plant roots and soil macrofauna over one growing season improved several aspects of bioretention cell function. The greatest increase in saturated hydraulic conductivity was in the treatment that included both plants and macrofauna. The presence of vegetation reduced ponding effects and increased water storage. Earthworm treatments had a lesser ability to store water. All treatments were effective in reducing the concentration of P in effluent. A large amount of N was released during all events from all treatments probably because of a high initial N content of the bioretention media. No treatment performed significantly better in improving water quality, indicating that macropore flow in the earthworm treatments did not induce a higher rate of pollutant transport.

Select this Article		Importance of Levees in the Kansas City Area David W. Renetzky, P.E., M. ASCE and John Grothaus ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)449 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Kansas City's deliberate location along the Missouri River at the confluence of the Kansas River played a key part in the city's rich history and prosperity. From the city's beginnings, the river was a way to link one part of the country to another through transportation and trade. It provided a means to westward expansion and free enterprise. From early on, though, the river demonstrated its power over those that settled along its banks. That brought rise to federal flood control which originated in the early 1900s as a coordinated attempt to provide flood protection. As flood control evolved, the Flood Control Acts of 1936 and 1944 allowed the construction of the existing protection system in Kansas City. The Kansas City metropolitan system of seven flood protection levee units protect vital infrastructure while the rivers continue to provide an important asset to the area. Major flood events in 1951 and 1993 proved the potential devastation to the areas along the Missouri and Kansas Rivers. The 1951 flood led to improvements on many of the levee units. An ongoing feasibility study as a result of the 1993 flood will determine what beneficial changes can be made for the future. Billions of dollars have been saved over the years through property damage prevention, along with an unknown number of lives. As the river continues to be an important part of Kansas City, so too does the flood protection system that surrounds it.

Select this Article		Kansas City, Missouri Wet Weather Solutions Program a Twelve Step Program Erin Ollig and Sheila Shockey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)450 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The measure of a successful public participation effort is not only sharing information, and gathering public input but also in changing behaviors on a larger scale. The Wet Weather Solutions Program was created by the City of Kansas City Missouri to reduce flooding, improve water quality and protect and restore the natural environment. To prepare the long‐rang plan, a large scale public participation process was employed. It resulted in an innovative plan but also drove significant changes to the culture of an entire city organization; and introduced and promoted sustainability throughout all aspects of the City. As a result of the public participation process, Kansas City is destined to be one of the greenest cities in the United States over the next 25 years. A unique perspective from inside the public participation process of a $4.0 billion public infrastructure project is outlined from the lead public participation consultants for the Program.

Select this Article		Kansas City, MO Overflow Control Program: Line Creek/Rock Creek Sanitary Sewer Study Jeffrey W. Davies, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)451 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Kansas City's Water Services Department (WSD) prepared a Long Term Control Plan (LTCP) to provide a roadmap to reduce the magnitude, frequency, and duration of combined sewer overflows (CSOs), and for the rehabilitation and improvement of the sanitary sewer system (SSS) to prevent sanitary sewer overflows (SSOs) and basement backups. The study area for this project includes the sanitary sewer system within the Line Creek, Rock Creek, Buckeye Creek, and Searcy Creek watersheds. The drainage area of these watersheds is approximately 25 square miles north of the Missouri River and contain 8‐in to 72‐in diameter sanitary sewers. A hydraulic model was developed using XP‐SWMM based on data collected from the City's Geographical Information System. Recommended improvements were evaluated to prevent SSOs, and preliminary cost estimates were developed.

Select this Article		Lake Winnebago Dam Relocation Project Jonathan L. Polak and Shannon W. Tyree ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)452 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Lake Winnebago, Missouri, is a tight‐knit community focused on providing residents with water‐based recreational opportunities on the existing 244‐acre lake. The original master plan for the community involved building two lakes; however, bankruptcy by the developer limited the community to one lake. Residents never lost their desire to complete the original lake plan and have partnered with South Winnebago Partners, LLC to complete the vision for the city. The project proposes to construct a new earthen filled dam downstream of the existing lake. The proposed dam is 65 feet tall and 1,440 feet long. Relocating the dam will expand the surface area of the lake from 244 acres to approximately 416 acres. The proposed project would result in placing fill material into jurisdictional waters of the United States, causing the unavoidable impact to 15,879 linear feet of stream and 16.57 acres of wetlands. Because this project is one of the largest regulated Corps of Engineers activities within the Kansas City metropolitan area, Olsson Associates was hired to complete Section 404 Permitting and mitigation planning.

Select this Article		Zona Rosa & Rush Creek Conservation Area — Applied Ecology in a Mixed‐Used Development J. J. Dremsa and D. M. Mensing ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)453 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In 2001, Applied Ecological Services, Inc. (AES) was asked to assist in the design and installation of restored native ecosystems and a restored stream and riparian corridor on the 200‐acre property proposed as the Zona Rosa mixed‐use development, located in Kansas City, Missouri. Following our analysis of over 1,950 linear feet of Rush Creek, a degraded stream within the property, AES designed restoration and bioengineering strategies for a variety of ecological zones, requiring various treatments. Design strategies were based on extensive hydrologic modeling and environmental engineering. Ecological restoration treatments along the Rush Creek Conservation Area (RCCA) included: native riparian buffer plantings, restoration of upland prairie, savanna and forest buffers, created in‐stream pools and riffles, and a variety of bank stabilization strategies using bioengineering techniques. These included brush layering, installation of live stakes and willow posts, and toe protection using biologs. Parking lot BMPs were selected to reduce runoff into the stream, and stormwater management treatments necessary to success of the project were also designed and constructed upstream of the site. Five‐year monitoring programs were developed to document water quality, vegetation success, erosion control, and stability of the stream system.

Select this Article		Modeling Impacts of Conventional and Low Impact Stormwater Controls on Receiving Streams Elise Ibendahl, P.E. and Dan Medina, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)454 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a methodology to measure the impact of stormwater controls on the receiving stream using a series of discrete events to represent the long‐term hydrologic regime as a simpler alternative to continuous simulation. Hydromodification impacts on channel morphology are best evaluated using flow and shear stress duration curves, which typically require continuous simulation. The methodology proposed herein allows the development of these duration curves using discrete events. The methodology was tested in a hypothetical development in the City of Columbia, Missouri. Design assumptions were made for a typical residential development and a typical stream. Various stormwater controls were designed for this site, including conventional detention, a water quality volume and channel protection volume basin, and bioretention. The outflow from each design scenario was analyzed to determine the effectiveness of different levels of stormwater controls. The objective was to compare the effect of each scenario using duration curves to measure its ability of mimic the original hydrology. The study indicates that LID most closely replicates the original regime and that detention provides some benefits when water quality and channel protection are included, although its effect does not reproduce the original hydrology. Detention criteria based on extreme events, such as the 100‐year storm event, are ineffective for this purpose.

Select this Article		Potable Water from a Superfund Site? Marc Schlebusch, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)456 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper will describe the beneficial use of contaminated groundwater after treatment to supplement a local potable water supply. Contaminated groundwater from Superfund sites is usually treated and discharged to a stream or storm sewer or conveyed to a wastewater treatment plant. Discharge of treated water is seen by many as a waste of resources, particularly in areas affected by drought. Beneficial reuse of this treated water as potable water is an attractive alternative, and can become a considerable asset, provided that community stakeholders are assured of the quality of the treated water and that treatment operations meet or exceed federal, state, and local requirements.

Select this Article		Riverside‐Quindaro Bend Levee (L‐385) on the Missouri River: The Essential Role of O&M and Documentation Gary W. Creason, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)457 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Riverside‐Quindaro Bend levee (L‐385 in the Missouri River levee system) was originally built as an agricultural levee in the 1920s, was authorized for study by the Flood Control Act of 1944, and drew heightened interest after 1993's major floods in the Midwest. Authorized for final design and construction in September 1997, construction was essentially completed in May 2005. Since then, there has been one high water event, and the levee performed as intended. The paper provides a brief history of the project, including organizational, legal, and regulatory requirements (including funding, floodplain management plan, operation and maintenance (O&M), flood fight planning, and recertification).

Select this Article		Protecting Infrastructure: Emergency Streambank Stabilization John Grothaus, Ken Markwell, P.E., Pete Jarchow, P.E., and John Blancett, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)458 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Emergency Streambank Stabilization program has been a vital part of protecting local infrastructure, including bridges and other utilities, from the dynamic rivers and streams in Missouri. The U.S. Army Corps of Engineers, Kansas City District has a long‐established emergency streambank stabilization program, carried out under Section 14 of the 1946 Flood Control Act. The program is cost shared 65 percent Federal, 35 percent local, and after construction, projects are turned over to the local partners, or “sponsors” for ownership and maintenance. In the region surrounding Kansas City, the program has consistently provided for projects which protect critical infrastructure such as roadways, bridges, and utilities, from severely eroding stream banks. Sponsors include counties, cities, Indian Tribes, and state departments of transportation. This paper presents two of ten projects built in the last ten years that have served two sponsors very well: the City of Parkville, Missouri and the Missouri Department of Transportation. Section 14 projects are developed and constructed in a multi‐stage process. This process includes evaluation of multiple stabilization techniques, including longitudinal peak stone toe protection (LPSTP), bank armoring, bendway weirs, dikes, jetties, sheet piling, bioengineering, and windrow revetments. The Section 14 program plays a key role in protecting rural and urban transportation and water infrastructure. It assists states and local governments in diligently monitoring and maintaining their infrastructure, supports economic health and development, and contributes to sustainable water resources in the community. Finally, Section 14 program is an example of a highly beneficial partnership between a Federal agency and state and local governments.

Select this Article		The Impact of Smaller Detention Basins on Flood Hazard Areas in Lenexa, Kansas Elangovan Karuppasamy, P.E., Natalie Postel, P.E., Christine A. Pomeroy, Ph.D., P.E., and Tom A. Jacobs, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)459 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In the early 1990s, the City of Lenexa, Kansas (City) adopted a flood control standard which required new developments to limit post‐construction 1‐percent‐annual‐chance flow rates to 2.79 cubic feet per second (cfs) per acre. In 2003, the City adopted new standards (American Public Works Association Specification 5600) that removed the 1‐percent‐annual‐chance requirement but included matching the 100‐percent‐annual‐chance and 10‐percent‐annual‐chance post‐development flow rates to pre‐development flow rates (Lenexa City Code, January 2008). As a result of these requirements, many detention basins have been constructed in the past two decades have not been included as part of a city‐wide flood hazard analysis. To remedy this omission, the City initiated the East Lenexa Detention Study (ELDS) to quantify the effect of the small detention basins on peak flow rates and water surface elevations. The purpose of this study was to evaluate the impacts of the smaller detention basins on flood hazard areas in Lenexa using HEC‐HMS and HEC‐RAS models. For the hydrologic analysis, HEC‐HMS models were used to simulate peak runoff from the 50 percent, 10 percent, and 1 percent annual chance storms. For the hydraulic analysis, HEC‐RAS models were used to estimate water surface elevations using the peak flow rates estimated by the HEC‐HMS model.

Select this Article		Water Quality of Streams in Johnson County, Kansas, 2002–07 T. J. Rasmussen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)460 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water quality of streams in Johnson County, Kansas was evaluated from October 2002 through December 2007 in a cooperative study between the U.S. Geological Survey and the Johnson County Stormwater Management Program. Water quality at 42 stream sites, representing urban and rural basins, was characterized by evaluating benthic macroinvertebrates, water (discrete and continuous data), and/or streambed sediment. Point and nonpoint sources and transport were described for water‐quality constituents including suspended sediment, dissolved solids and major ions, nutrients (nitrogen and phosphorus), indicator bacteria, pesticides, and organic wastewater and pharmaceutical compounds. The information obtained from this study is being used by city and county officials to develop effective management plans for protecting and improving stream quality. This fact sheet summarizes important results from three comprehensive reports published as part of the study and available on the World Wide Web at http://ks.water.usgs.gov/Kansas/studies/qw/joco/.

Select this Article		Water‐Quality Assessment of the Largely Urban Blue River Basin, Metropolitan Kansas City, USA, 1998 to 2007 Donald H. Wilkison, Daniel J. Armstrong, and Sarah A. Hampton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)461 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract From 1998 through 2007, over 750 surface‐water or bed‐sediment samples in the Blue River Basin — a largely urban basin in metropolitan Kansas City — were analyzed for more than 100 anthropogenic compounds. Compounds analyzed included nutrients, fecal‐indicator bacteria, suspended sediment, pharmaceuticals and personal care products. Non‐point source runoff, hydrologic alterations, and numerous waste‐water discharge points resulted in the routine detection of complex mixtures of anthropogenic compounds in samples from basin stream sites. Temporal and spatial variations in concentrations and loads of nutrients, pharmaceuticals, and organic wastewater compounds were observed, primarily related to a site's proximity to point‐source discharges and stream‐flow dynamics.

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PLANNING AND MANAGEMENT

Select this Article		A Bayesian Framework for Cost Effective Management of Sediment Reduction in the Minnesota River Basin Sarah K. Jacobi, Pearl Zheng, Benjamin F. Hobbs, and Peter R. Wilcock ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)462 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water quality impairments remain a pressing concern in the United States. Selecting appropriate management actions (i.e., best management practices) to improve water quality involves tradeoffs between cost and effectiveness, both of which are prone to uncertainty. In addition, significant uncertainties exist in the scientific understanding of the natural system. To address these concerns, we have developed a framework to identify the optimal set of actions to reduce turbidity and sedimentation in the Minnesota River Basin, while explicitly incorporating uncertainty. The framework combines Bayesian inference with multiobjective programming models to select the optimal combination of research actions, which improve our understanding of the natural system, and management actions, which reduce sediment contributions to the river basin. We also evaluate the value of information of each research action, to identify where further study is warranted. Our results communicate the general nature of the tradeoffs and complex interactions among sediment loadings, best management practices, and the possible research projects. More important, our results indicate that explicit consideration of uncertainty can lead to improved selection of management actions that most accurately address the complexity of the problem.

Select this Article		A Decentralized Optimization Algorithm for Multi‐Agent System Based Watershed Management Yi‐Chen E. Yang, Ximing Cai, and Dušan M. Stipanović ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)463 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A watershed can be considered a multi‐agent system (MAS) composed of water users (agents) spatially distributed in a distinct manner within a common defined environment from which they can all access a particular resource. The watershed system is characterized by distributed decision processes at the agent level and a coordination mechanism organizing the interactions among individual decision processes. This paper presents a decentralized optimization method known as constraint‐based reasoning, which allows individual agents in a multi‐agent system to optimize their behaviors. The method incorporates the optimization of all agents' objectives through a bargaining scheme, in which the i^th agent optimizes its objective with a selected priority for collaboration and sends the solution back to all agents that interact with it. This methodology allows agents to determine how important their own objectives are in comparison to the constraints, using a local interest factor (β_i). A large β_i value indicates a selfish agent who puts high priority on its own local benefit and ignores constraints. This analysis is applied to a hypothetical watershed with three offstream human agents (city and farms), one instream human agent (reservoir) and two ecological agents (fish habitat in the river). The proposed approach takes the objectives of individual agents into account and balances them through interactions among the agents. This bottom‐up problem‐solving approach mimics real‐world watershed management problems better than conventional “top‐down” optimization methods in which it is assumed that individual agents will completely comply with any recommendations that the coordinator makes.

Select this Article		A Decision Support System for Water Resources Planning and Management for the North Slope of Alaska Amy C. Tidwell, Kelly Brumbelow, Stephen F. Bourne, and William E. Schnabel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)464 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Alaska's North Slope hosts a phenomenal wealth of natural, cultural, and economic resources. It represents a complex system, not only in terms of the biophysical system and its global importance but also from the standpoint of its social dynamic. A major challenge at the forefront of domestic energy development on the North Slope is the need for best management practices that will ensure benefits for all stakeholders. To do so requires stakeholder cooperation that enables cost‐effective development strategies that fit within a broader context of long term cultural, economic, and environmental sustainability. Ice roads and ice pads provide a cost‐effective means of oil and gas exploration with minimal impact to the sensitive underlying tundra. Consequently, these ice structures have become integral to oil and gas exploration activities on the North Slope. Their widespread use represents a challenge to water resource managers, however, due to the large volume of water required to construct and maintain them. Crucial questions on water balance and ecosystem impact must be considered in the state regulatory process that permits construction of these ice structures. The North Slope Decision Support System (DSS) is currently under development as a technology in support of oil and gas exploration and development that explicitly considers optimal water use, direct and cumulative environmental impacts, and multiple objectives and values among stakeholders. Major modules of the DSS include information systems, natural system models, planning and management functions, and regulation workflow. Development of the DSS is a collaborative effort of academic and industry personnel with significant stakeholder involvement from multiple agencies of local, state, and federal government, private energy companies, and non‐governmental organizations.

Select this Article		A Framework for Determining the Possible Impacts of a Changing Climate on Water Supply Mark Summerton and Roland Schulze ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)465 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract For effective water resources management, all “stressors” that may impact on balancing future water supply and demand must be assessed. Hydrologists have recently begun making headway towards assessing a previously ignored “stressor”, viz. the impact of a changing climate. At Umgeni Water, a bulk water utility in South Africa, a process has been initiated to quantify potential impacts, initially on strategic catchments using daily physical‐conceptual hydrological modelling. Preliminary results indicate that streamflow could increase by up to 2.6 and 5.3 fold by the year 2065 and 2100 respectively, mostly in the currently dry winter months. Furthermore, inter‐annual variability could decrease. This could increase risks of flooding and compromise dam safety. Should additional streamflow improve water yields, climate change could potentially benefit cash flows by delaying capital expenditure on projects to improve assurance of supply. Regardless, it is imperative that the hydrological consequences of a changing climate be included in water development, disaster risk and system operating plans.

Select this Article		A GIS‐Based Decision‐Making Methodology for Evaluation of Environmental Justice Impacts of Community Infrastructure Projects James S. Cole, M. ASCE, Kathleen M. Trauth, Ph.D., P.E., M. ASCE, and Yingkui Li, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)466 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Advances in geospatial analysis technology have resulted in new data‐gathering techniques for environmental justice (EJ) assessments. Frequently investigated metrics relate to race and income due to relatively easy availability of census data. Geographic information systems (GIS) offer the ability to embed these data in maps in order to better recognize patterns that may designate discriminatory practices. Many other indicators of disproportionate negative effects exist and can be assessed using GIS. Map‐based analysis results can also provide data on proximity for various phenomena. However, expert human analysis is required to interpret images which may lead to arbitrary or subjective conclusions. Researchers at the University of Missouri have developed a GIS methodology to overcome the limitations of image‐based analyses for evaluating spatial relationships in community infrastructure by employing metrics such as travel time and distance to jobs, education, healthcare, and food markets in order to move beyond identification of those affected to quantification of the impacts on their lives. That is, to quantify the answers to the questions: How does daily life change as a result of infrastructure improvements? How do the impacts on these parameters compare to the impacts of alternative projects? Manifestations of these impacts have been transformed into quantifiable data that will offer planners greater decision‐making confidence. Mathematical representations in the form of indices have been developed to offer a consistent approach to infrastructure problems as they relate to EJ.

Select this Article		A Pragmatic Cycle for Ongoing Water Resources Research and Management Thomas L. Singleton, Stephen Bourne, P.E., and Jack Hampson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)467 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Organizations focused on managing water resources are recognizing the need to have tools for literature review, data integration, modeling, and decision support. Decision support systems (DSS) can help to meet these needs because they are aimed at integrating data and knowledge, evaluating management options in terms of organizational objectives and risk, and facilitating multiple‐stakeholder decision making where competing objectives and risk preferences must be reconciled. Using the internet, organizations can share the costs and benefits of existing and newly developed information, theories, and technologies among a broad, diverse user group. This paper discusses an approach, based on experience, to developing DSSs through a larger, iterative cycle of ongoing, collaborative environmental research and development. Multiple stakeholders with multiple conflicting objectives need insightful, often novel, models of environmental systems. The answers developed to new research questions contribute to requirements and specifications for new tools and technology, and the technology is then built to facilitate the collaborative management process. Information added at any point can influence the collaborative management‐research‐technology cycle in both directions.

Select this Article		A Spatio‐Temporal Drought Analysis for the Midwestern US Shih‐Chieh Kao, Rao S. Govindaraju, and Dev Niyogi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)468 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Droughts are prolonged abnormalities of moisture deficits that vary widely across temporal and spatial scales. Many hydrometeorologic variables are used to monitor the status of a drought. However, because of the dependence structure between all affecting variables under various temporal windows, an integrated spatio‐temporal analysis of droughts cannot be easily achieved. In this study, a copula‐based drought analysis was performed by using long‐term monthly precipitation dataset for the upper Midwest United States. The spatio‐temporal dependence relationships between various drought variables were investigated, and their joint probability distribution was constructed by combining drought marginals and the dependence structure. A copula‐based joint deficit index (JDI) was adopted for an objective (probability‐based) description of the overall drought status and compared to the Palmer drought severity index results. Results from the copula‐based JDI provide information for drought identification, and further allow a month‐by‐month assessment for future drought recovery.

Select this Article		Agent Based Models for Simulation of Watersharing in a River Basin S. Mohan, Professor and K. Santhosh Kumar, Graduate Student ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)469 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water‐sharing in a river basin by different users as well as between different stakeholders along the river basin has been a serious problem and becomes more complex when there is an acute shortage of supply in the river basin. Many negotiations and interactions take place between the farmers as well as between the watersupplier and the farmers before the actual water allocation takes place. This paper presents a novel approach of agent based modeling for solving the water allocation problem. Agent based modeling using a multi‐agent approach has been used to represent the various interactions between stakeholders during the process of water allocation. The spatial multi‐agent programming model has been used for assessing the performance of the water allocation strategies. It is found that the developed model could provide the various possible scenarios and their consequences to the decision makers. The developed model is very generic and consists of a group of farmers with different farm sizes and crops, and a water supplier who does the allocation. The water allocation rules are built into the functioning of the models and are used to evaluate the performance of the developed rules. The performance indicators adopted in this model include individual farmers view point where one could observe the water needs and water allocated per unit area, global viewpoint with the overall yield, and the ethical viewpoint with disparities in water allocation and yields. It is found that the developed model has been proved to be successful to evolve a compromise and effective solution for the water allocation problem, when the model was applied to a case‐study in Tamilnadu, India.

Select this Article		Analysis on Effect to EVW from Policy Intervention Ruan Ben‐qing, Zhang Chun‐ling, Wang Cheng‐li, and Xu Feng‐ran ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)470 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract High benefit utility of water is one of the main goals on water management activity. Calculational economic value of water (EVW) of industry by appropriate method can express the benefit of water use, which may be intervened by some policies, such as industry structure adjusting, water pricing, and product techniques innovating ect. The effects to EVW from the policies intervention in Beijing are discussed, which will be propitious to perfect policy on water use.

Select this Article		Application of Genetic Algorithms for Estimation of Flood Routing Model Parameters S. Mohan, Professor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)471 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Flood routing through rivers and channels is an essential activity in hydrological analysis and this is particularly important because of the increasing emphasis that has been placed on dam‐safety worldwide and due to the increasing urbanization near river channels. The routing of flood through river channels may be accomplished using two basic approaches namely hydrologic routing approach and hydraulic routing approach. There are different methods currently in usage and the Muskingum method is the most popular method and generally used by hydrologists and engineers. However, the reliability of this method is heavily depends upon the accuracy of the parameters namely K and x or C₀, C₁ and C₂ of the model. These parameters are usually estimated by trial and error procedure. Muskingum model together with the Model proposed by Loucks (1989) have been considered for the present study and the parameters of these models were estimated using genetic algorithms, new search procedures for function optimization that apply the mechanics of natural genetics and natural selection to explore a given search space. This paper presents the results of the study of application of genetic algorithm for optimal parameter estimation of both linear and non‐linear flood routing models to a case study. The sensitivity analysis of these estimated parameters was also carried out. The results had clearly depicted that the genetic algorithm is an efficient and robust means for estimation of flood routing model parameters.

Select this Article		Application of Multi‐Objective Differential Evolution Algorithm (MDEA) to Irrigation Planning Josiah Adeyemo and Fred Otieno ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)472 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Farmers in a water scarce environment have a problem of maximizing total income from farming. Irrigation planning is very important to prevent crop failures. DE, an evolutionary algorithm, which is a stochastic parallel direct search evolution algorithm known to be fast and robust in numerical optimization, is extended to multi‐objective problems in this study. The new algorithm named multi‐objective differential evolution algorithm (MDEA) adjusts the selection scheme of traditional DE to solve multi‐objective problems. The algorithm also modifies the domination criteria for the population. The offspring generated in subsequent generations are improved before domination check is performed on the population in the final generation. MDEA is tested on three benchmark problems and later applied to an irrigation planning. The algorithm achieves the two goals in multi‐objective optimization algorithm which are to discover solutions as close to the Pareto‐front as possible and to find solutions as diverse as possible in the obtained non‐dominated front.

Select this Article		Assessing Potential Implications of Climate Change for Long‐Term Water Resources Planning in the Lower Colorado River Basin Susan Butler, AICP, Armin Munevar, P.E., Ron Anderson, P.E., and Joseph Rippole, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)473 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Lower Colorado River Authority (LCRA) — San Antonio Water System (SAWS) Water Project is being studied to conserve water, develop conjunctive groundwater supplies, and capture excess and unused river flows to meet future water needs for two neighboring regions in Texas. Agricultural and other rural water needs would be met on a more reliable basis in the lower Colorado River basin through water conservation, surface water development and limited groundwater production. Surface water would be transferred to the San Antonio area to meet municipal needs in quantities still being evaluated. The project is in its sixth year of detailed studies addressing environmental, agricultural, socioeconomic, and engineering aspects of the project. Tools are being developed and used in project planning including instream flow criteria, water quality assessments, bay freshwater inflow criteria, surface water availability models and operating approaches, agricultural conservation measures, groundwater models, and economic models.

Select this Article		Asymptotic Variance of Regional Growth Curve for Generalized Logistic Distribution Hongjoon Shin, Woosung Nam, Younghun Jung, and Jun‐Haeng Heo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)474 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The index flood method was introduced by Dalrymple to overcome the difficulties to obtain reliable estimates of the quantiles from relatively short record length. However, the application of index flood method must account for the additional uncertainty due to estimation of index flood at site. One must account for the uncertainties of the quantile estimates and those associated with the index flood. In this study, the generalized logistic distribution is considered as a an appropriate model for regional frequency analysis in Korea based on the method of probability weighted moments under the assumption that the regional quantiles and the index flood at site are independent. An approximate formulation of the variance of the quantile is introduced to evaluate the uncertainty of the estimated growth curve.

Select this Article		Balancing the Budget: A Limited Detail Approach to Flood Studies Andrew J. Bonner, P.E., CFM ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)475 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Floodplain or inundation mapping studies are performed for a variety of reasons, and are many times only one phase of a larger engineering or mapping project. As is often the case, many communities and agencies write their scope so that their project's flood studies are performed in accordance with FEMA guidelines, with the intention of incorporating those studies onto FEMA's flood maps in the future. More times than not, this results in the development of a project scope that would fit FEMA's definition of a “detailed study” — field survey, development of the 10‐, 50‐, 100‐, and 500‐year flood profiles, etc. However, in certain instances, it may be appropriate to apply a more “limited” detail approach to the study area, while still being able to meet project objectives. This paper will focus on the various floodplain study methodologies that have been accepted by FEMA (approximate, limited detail, and detailed), when and where each study type can be used, and the similarities and differences between the three. The limited detail approach will specifically be explained and highlighted as a potential solution to bridge the gap that often exists between budget and accuracy needs. Several case studies will be presented to show the difference in steady flow HEC‐RAS modeling and mapping results between the study types.

Select this Article		Climate Flow Forecast Model for the Brazilian Hydropower System Mario T. L. Barros, João E. G. Lopes, Renato C. Zambon, Alberto L. Francato, Paulo S. F. Barbosa, and Fabio R. Zanfelice ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)476 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Brazilian Hydropower System (SIN) is composed today by 107 hydropower plants with 81,036 MW of installed capacity. The system is completely connected due to the Brazilian heterogeneous hydrology. The flow forecast is a very important tool to operate SIN and to other decisions involved in the Brazilian electrical sector. This paper aims to present a model for SIN flow forecasting done in a climate basis, in a monthly basis considering rainfall forecasts for six months ahead. The rainfall forecasts are done by the Brazilian Center for Weather Forecast and Climate Studies (CPTEC). The CPTEC climate forecasting model covers the South America continent and produces forecasts in two grids, 200 by 200 Km and 40 by 40 Km. The flow forecast is done by two hydrological methods. One is the rainfall‐flow model SMAP (Soil Moisture Accounting Procedure) by and the other a stochastic linear model (MEL). The final forecasts are defined by a weigh function considering SMAP and MEL forecasts. The flow forecast model is called GERAVAZ and was design using a decision support system frame in order to be practical to users. GERAVAZ was applied to twenty basins covering the main Brazilian rivers. These twenty forecasts are the reference to produce the inflow forecasts to all SIN reservoirs. Preliminary results are quite promising and have great evidences of the potential application of this modeling tool.

Select this Article		Collaborative Groundwater Model Development David W. Barfield ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)477 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In our day of increasing conflicts for water resources, water management decisions require the understanding of the hydrologic nature of the interactions between water use and the water resources. In Kansas, conflicts for water resources occur at both the interstate and intrastate level, and have led to the development of groundwater models as tools for water management decision‐making. In the past, groundwater model construction has typically been the responsibility of a single entity, with limited technical input from agencies and/or interested constituents, and peer review generally at the end of the model construction process. This has led to models with limited buy‐in from the regulated community, limiting their usefulness in difficult and contested water management decisions. A robust, collaborative model development process was used in the development of the Republican River Compact Administration groundwater model by the states of Colorado, Kansas and Nebraska as part of their settlement of their compact litigation in 2002. More recently this model development process was used to build the Middle Arkansas River Basin groundwater model in south‐central Kansas. The model development process used allowed multiple experts to review model datasets and calibration targets, test modeling assumptions, explore various modeling approaches, and determine when model construction was complete. While the process requires greater commitment of total resources, in both cases the process led to good, practical, defendable models, which are being used as tools to guide important water management decisions.

Select this Article		Communicating Drought Severity and Re‐Evaluating Firm Yield — Cumberland County, Tennessee as a Case Study Lars Hanson and Stuart Stein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)478 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The 2007 drought in Cumberland County, Tennessee greatly strained the three reservoirs that provide the large majority of the county's water supply and prompted a new analysis of the reservoirs' firm yield. With the reservoirs lacking long term streamflow and operations records, traditional yield analysis could not be performed directly. A multi‐scale Standardized Precipitation Index (SPI) analysis was conducted, and the resulting multi‐scale SPI plot was found to be a highly effective tool for communicating the drought severity of the current drought relative to past droughts. A simple, continuous‐simulation HEC‐HMS model was used to generate a synthetic streamflow record, and determine the critical drought period for each reservoir using the traditional sequent peak algorithm. Using the sequent peak algorithm, storage‐yield relationships a multiple yield cumulative deficit plot were created as useful tools for explaining reservoir behavior. This is part of a County‐wide water supply plan being developed by the US Army Corps of Engineers, which includes projecting future water demand, evaluating potential conservation measures, and evaluating sources to meet the growing demand.

Select this Article		Computer Aided System for Managing, Controlling and Analyzing Data from Hydroelectric Plants Ieda G. Hidalgo, Darrell G. Fontane, Secundino Soares Filho, and Marcelo Augusto Cicogna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)479 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a computer aided system for managing, controlling and analyzing data from hydroelectric plants. The proposed system consists of three modules. The first is a relational database that organizes, standardizes and manages data from hydroelectric plants. The second module allows a user to build, store and manage advanced queries on this or certain other databases. The third is a simulator of the hydroelectric plants operation which can be used for planning the future operation or reproducing the past operation. The computational implementation of these modules uses the Object‐Oriented Paradigm, the C++ Programming Language and the Structured Query Language (SQL). The data manager, the queries builder and the simulator were tested with data from Brazilian hydroelectric plants and the results show the potential of this system for the analysis and consistency evaluation of data from hydroelectric plants.

Select this Article		Copula Approach for Reducing Uncertainty in Design Flood Estimates in Insufficient Data Situations Hemant Chowdhary and Vijay P. Singh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)480 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sufficiently long period of data is required for making sound flood estimates corresponding to the design return periods. Such long‐term and good quality flow data is often a difficult proposition, especially in developing and under‐developed countries. Most watersheds in these countries that are of immediate interest and concern are either completely ungauged or are insufficiently gauged. Flood estimates in situations of inadequate length of data invariably involve large amounts of uncertainties. There is a growing interest in investigating if these uncertainties in flow estimates can be reduced by supplementing the limited flow data with that available at adjoining river gauging station(s) on the same river or that in the adjoining river basins. It is expected that additional information can be derived from the dependence among flow characteristics at these adjoining flow stations when they are considered together. The maximum likelihood procedure, with likelihood function involving univariate and joint probabilities corresponding to exclusive and concurrent periods of data availability, is employed for estimating parameters of flood frequency distributions. Copula‐based bivariate distribution approach offers advantage over conventional functional forms by admitting arbitrary marginal types that are dictated by the nature of the flow regimes at these river stations under consideration. This paper presents a comparison of uncertainties in the estimated flood quantiles at a station with limited data, as obtained from the univariate consideration and that from the simultaneous consideration of additional flow data from a neighboring river gauging station. A significant reduction in uncertainty achieved by this approach indicates that substantial improvements in the accuracy of flood estimates can be made by multivariate consideration of flood frequency analysis that is facilitated by copula approach.

Select this Article		Deriving Rule Curve for Hydropower Reservoirs; Seymareh Experience F. Sharifi, M. R. Jalali, and R. Afzali ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)481 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A common method of design and operation of hydropower dams in Iran is based on peaking hours. In other words, monthly network demand (peak hours multiplied in install capacity) will be fully produced if the water level of reservoir in that month is between Minimum Operating Level (MOL) and Normal Water Level (NWL). If it is located under MOL or above NWL, the water level will be fixed on MOL or NWL and energy production will be lowered or increased, respectively. In order to take into account different monthly values of energy, implementing of an operating policy and rule curve is indispensable. The main goal of this study is to derive a set of monthly target storage elevation as a rule curve to operate the powerplant of Seymareh reservoir in West‐South of Iran. The main simulation model of Seymareh reservoir and powerplant is developed in Vensim Environment using System Dynamics (SD) approach. In this process, all the technical and practical details of this reservoir are taken into account. Relations between discharge and turbine efficiency and tail water, volume‐area‐elevation relations, reservoir evaporation, overload coefficient and maximum and minimum allowable head and turbine discharge are some of these details. Energy production will be occurred if the water elevation of a particular month of reservoir is located above the defined target elevation of that month. This process is performed on historical time series aiming to maximize mean annual value of generated energy. In the next part of this study, to avoid the trial and error process of target elevation selection of above discussed simulation model, a simple ACO algorithm with an embedded coded simulation model is implemented. Results show the ability of this algorithm in defining a rule curve for an absolutely practical case study.

Select this Article		Detection of Streamflow Trends and Variability in Karun River‐Iran as Parts of Climate Change and Climate Variability Alireza Farrokhi and Ahmad Abrishamchi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)482 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the application of statistical and spectral procedures that identifies trends and periodicity in streamflow time series. The results of Mann‐Kendall and seasonal Kendall tests (non‐parametric tests which are known as appropriate tools in detecting linear trends of hydrological time series) shows negative trends especially during low water months (August to November). This downward trend is more significant in October. But these methods can not interpret periodic behavior. Hence spectral procedures were applied on data series to investigate periodicities in streamflow data series. Fourier and Continuous Wavelet Transform (CWT) analyses produce evidence of interannual variability (3–4 and 5–6 years), especially in Karun River. These oscillations can be related to ENSO phenomenon. Also we observed near decadal, PDO‐related variability. However, the short length of the streamflow series can obscure such these results.

Select this Article		Developing Artificial Neural Networks to Represent Salinity Intrusions in the Delta Francis I. Chung and Sanjaya A. Seneviratne ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)483 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Impacts of 1 ft and 2ft sea level rise on Delta operations and salinity increases at export locations are quantified in this memo. California Department of Water Resources (DWR) uses many numerical models to study the Sacramento‐San Joaquin Delta operations. Delta Simulation Model (DSM2) was used to calculate the salinity at some key locations in the Delta and to train Artificial Neural Networks (ANN) for each of the sea level rise scenarios. ANNs generated here are flow salinity relationships that calculate electrical conductivity (EC) at a given location using Delta boundary flows. CalSim II (Central Valley Project and State Water Project operation model) was used to determine the extra cost of water to mitigate the sea level rise. In this study current operation rules specified in State Water Resources Control Board's (SWRCB) Water Right Decision 1641 (D 1641) were assumed unchanged.

Select this Article		Developing Best Practices for Computer Aided Dispute Resolution S. Langsdale and L. Bourget ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)484 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Computer aided dispute resolution (also known as collaborative modeling or shared vision planning) combines technical analysis and modeling with collaboration and traditional planning principles in order to address complexity, manage conflict, promote learning and understanding, and build relationships among stakeholders. The participatory process enhances model credibility, while the model supports the decision‐making process and promotes group learning. Computer aided dispute resolution is a relatively new field, and current practitioners generally have a unique mix of technical and process skills that enable them to conduct this groundbreaking work. To train the next generation of practitioners and to ensure high quality work, we must identify and communicate the necessary skills and practices that support successful processes. With this objective, in the fall of 2008, the Environmental and Water Resources Planning and Management Committee established a task committee to formulate and document best practices in this developing field. The task committee will deliberate and advise which elements of the case study context, team member skills, process design elements, and modeling approaches are critical for incorporating computer aided dispute resolution into water resources planning and management successfully. The products of this task committee will include a written monograph, dissemination of results at conferences, and an evaluation of next steps. In this presentation, we will share progress to date and invite audience feedback and participation.

Select this Article		Development of a Fuzzy Based Pipe Condition Assessment Model Using PROMETHEE Yi Zhou, Kala Vairavamoorthy, and Frank Grimshaw ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)485 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The deterioration of pipes in water distribution systems is a serious problem for water utilities. In order to rehabilitate the deteriorated pipes in a planned and proactive way, there is a need to have a better understanding of pipe condition assessment. Pipe condition assessment can be regarded as a multiple criteria decision making problem. A new model for pipe condition assessment is developed using fuzzy PROMETHEE II. The model processes four first‐level and seven second‐level pipe condition indicators and then generates a pipe condition index for each pipe in the system. The weight for each indicator is generated by using Analytic Hierarchy Process (AHP). The paper presents the application of the new method to some pipes in a water distribution system. This application demonstrates both the stability of the new method and its ability to generate results that will greatly assist decision makers in the development of their rehabilitation strategies.

Select this Article		Development of Regression Models to Estimate Flow Duration Statistics at Ungaged Streams in Oklahoma Using a Regional Approach Rachel A. Esralew ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)486 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Multiple‐regression analysis was used to develop equations for estimating annual and seasonal flow‐duration statistics at ungaged streams in and near Oklahoma that are not substantially affected by human alteration. Ordinary least‐squares and left‐censored (Tobit) multiple‐regression techniques were used to develop equations that relate these statistics, from continuous streamflow data at gaged locations with 10 or more years of record, to physical and climatic basin characteristics. Separate equations were developed to estimate these statistics for stations within similar hydrologic and geologic regions. Use of separate regressions by region substantially improved the accuracy of the estimate for streams in eastern and central Oklahoma when compared with estimating equations developed for the entire State, especially for regressions estimating lower flow duration values. For all regions, the equations were more reliable for estimating higher flow duration values. The accuracy of regressions for estimating flow duration statistics in western Oklahoma was very poor, especially for lower flow duration values.

Select this Article		Development of Sustainable Water Supply Scheme in Reservoir Operation: Case Study M. Karamouz, S. Nazif, and S. Mohammadi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)487 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The development of societies is dependent upon the sustainable water supply through sound management of resources. It is important to determine the sustainable capacity of the water resources if further development is needed. Reservoirs play an important role in water supply of basins in arid and semi‐arid regions. In this paper a methodology is proposed to find a sustainable water supply scheme in reservoir operation considering the impacts of climate change on inflow and water demand variations. Different approaches such as deterministic and chance constraint optimization models are utilized for this purpose in both monthly and annual time scales. The objective function of the optimization model is to maximize the minimum reservoir release. As extreme dry or wet years can highly affect the model results, their effects on the reliable water supply are also evaluated. The proposed method has been applied to the Sattarkhan Reservoir located in Ahar‐chay basin in northwest Iran. Through the probabilistic approach, the reservoir operation can be managed with different risk levels and potential hazards. The results show that the reservoir has been overdesigned and it could carry only 60% of its capacity. Furthermore, the potential water resources in the studied basin are decreasing.

Select this Article		Developments on Stochastic Analysis, Modeling, and Simulation (SAMS 2009) J. D. Salas, O. Sveinsson, T. S. Lee, W. Lane, and D. Frevert ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)488 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Stochastic Analysis Modeling and Simulation (SAMS) is a software where stochastic techniques are utilized for simulating synthetic water resources data such as monthly streamflows. The current version, SAMS 2007, includes alternative modeling approaches and data analysis features. The stochastic models included in SAMS 2007 are parametric models such as multivariate autoregressive and disaggregation linear models. SAMS 2009 is now available. Various alternatives and options have been added particularly nonparametric techniques. The main purpose of this paper is to summarize the capabilities of SAMS 2009.

Select this Article		Does Collaborative Modeling Lead to Better Management of Our Water Resources? S. Langsdale and W. Michaud ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)489 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Shared Vision Planning (also known as Collaborative Modeling or Computer Aided Dispute Resolution) is a relatively new but growing field. Advocates claim that the method increases the quality of decisions and policies in a way that is “cheaper, better, and faster” than traditional decision making or dispute resolution without computers. But can we prove this? In an attempt to find out, the Corps of Engineers' Institute for Water Resources and SRA International developed an array of performance measures to see if the benefits of shared learning and better policies are achieved, as well as to explore what factors (e.g., transparent model, trusted facilitator) are critical for producing the intended outcomes. The performance measures seek to characterize the quality of the participatory process, the quality of the resulting model, what impact the model had on the process and any policy recommendations, and if the process produced any longer‐term impacts such as building institutional capacity and social capital. Results of assessing case studies using the performance measures will be presented.

Select this Article		Flow Augmentation for Dissolved Oxygen Improvement in Chicago Waterways Emre Alp, Charles S. Melching, M. ASCE, and Richard Lanyon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)490 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Even though treatment plant (water reclamation plant [WRP]) effluent concentrations meet the applicable standards and most reaches of the Chicago Waterway System (CWS) meet applicable water quality standards, dissolved oxygen (DO) standards are not met in the CWS during some periods. DO deficiencies particularly result in reaches subject to periods of limited flow, such as the upper North Shore Channel (NSC). Thus, an Use Attainability Analysis was initiated to evaluate what water‐quality standards can be achieved in the CWS. Flow augmentation practices evaluated for the upper NSC included: i) a portion of the North Side WRP (NSWRP) effluent was transferred to the upstream end of the NSC, ii) the flow was transferred to and divided between two discharge points—one at the upstream end of the NSC and the other at 2.80 km upstream from the NSWRP. It was found that shifting the entire NSWRP effluent flow to the upstream end of the NSC could not achieve 100 percent compliance with a 4 mg/L DO criterion along the upper NSC. Another augmentation alternative was to add oxygen to the NSWRP effluent in the force main, and this transfer of oxygenated effluent was found to effectively improve DO in the upper NSC.

Select this Article		Examining the Flow Regime Alteration and Its Potential Impacts to Freshwater Ecosystems under Changing Climate Conditions Jian‐Ping Suen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)491 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper uses observed daily streamflow data to examine the flow regime alteration and how these changes might potentially affect freshwater ecosystems. The earth surface temperature has been observed gradually increase and associate with precipitation and atmospheric moisture changes over space and time. Climate induced flow regime changes are examined by Indicators of Hydrologic Alteration approach. The annual extreme water conditions (1‐, 3‐, 7‐, 30‐, 90‐ day annual minima or maxima) reveal larger alteration from analyzing twenty‐three gauging stations throughout Taiwan. More severe flood and drought events happen in the period of after 1991 than the period of 1961–1990. Frequency and duration of the flood and drought events also reveal high fluctuation. Flow regime is being altered and is going to continue into the foreseeable future. The aquatic organisms not only need to defend themselves from the anthropogenic damage to the river system but also are facing the on‐going threat from thermal and flow regime altering under changing climate. This paper tries to raise this issue to allow water resources managers taking some precautionary measures to reduce the cumulative effects from anthropogenic influence and changing climate.

Select this Article		FEMA Flood Map Accuracy David R. Maidment ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)492 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract FEMA is completing $1 billion 5‐year program to modernize its flood insurance rate maps and convert them to digital form. At the request of FEMA, the National Academies of Science and Engineering have established a Committee on FEMA Flood Maps to review the accuracy of these maps and to recommend cost‐effective improvements to them. The Committee's report “Mapping the Zone: Improving Flood Map Accuracy” was released in January 2009. The Committee examined the relative effects of accuracy of hydrologic, hydraulic and terrain information on riverine flood maps, the factors affecting the accuracy of coastal flood mapping, and the costs and benefits of various levels of detail of flood mapping and modeling, using case studies set in North Carolina. This paper focuses on the riverine flood map accuracy portion of the report, and concludes that accuracy of the terrain data is the most important factor influencing riverine flood map accuracy.

Select this Article		Generating Different Scenarios of BMP Designs in a Watershed Scale by Combining NSGA‐II with SWAT P. Kaini, K. Artita, and J. W. Nicklow ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)493 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A multi‐objective optimization technique, Non‐dominated Sorting Genetic Algorithm (NSGA‐II), is coupled with a semi‐distributed hydrological model, Soil and Water Assessment Tool (SWAT) with the objective of generating a set of non‐dominated solutions. The model is formulated to optimize two conflicting objectives: the cost of structural Best Management Practices (BMPs) and the treatment goal. The cost of the BMPs is the function of type, size, and location of BMPs; whereas, the treatment goal considered is the reduction in annual sediment load the watershed outlet. Structural BMPs included in the modeling include detention ponds, infiltration type detention ponds, parallel terraces, filter strips, and grade stabilization structures which are applicable in agricultural watersheds. The model is demonstrated on Silver Creek watershed, a sub watershed of Lower Kaskaskia in Illinois. SWAT delineates watershed into 159 subbasins and are considered as potential locations of BMPs. The model came up with a Pareto front, which comprises a set of non‐dominated solutions, a set of least cost solutions for different level of annual sediment load reduction.

Select this Article		Hardening a Great and Growing City's Water Supply Scott Knight, E.I.T., Engineer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)494 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Cities across the West face the threat of dwindling water supplies. Issues such as climate change, competing supplies, and litigation threaten water availability for municipal uses. In Colorado, where approximately 86 percent of water is used for agriculture (CFWE 2005) and the system of administration is prior appropriation, adequate water supply in an increasingly competitive market is no longer a certainty. Many municipalities whose systems are based on junior water rights have been forced to turn to innovative — and expensive — projects to develop the water supplies of the future. The City of Aurora, Colorado is a suburb to Denver and the third largest city in the state, with a 2008 population of nearly 312,000. For Aurora Water, meeting the increased thirst of a burgeoning city is a challenge. Continued growth and a possibly dwindling water supply have necessitated an evaluation of the city's water infrastructure and “out‐of‐the‐box” planning to ensure that a reliable water supply is available for the future. In 2002, low rainfall and runoff brought the system's vulnerability to attention. With seemingly no water available to increase storage levels, reservoir levels fell to 25 percent full in March 2003, well below the desired minimum level and an adequate supply for only six months of indoor use in the City. This situation made perfectly clear the need for guaranteed reliability in the face of continued pressure on available water supplies.

Select this Article		High Resolution Radar Precipitation Evaluation Dennis Miller, Shaorong Wu, David Kitzmiller, and Feng Ding ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)495 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A series of experiments were undertaken to determine if any operational benefit might be realized from an upgrade of WSR‐88D hourly precipitation products to the highest spatial resolution now possible, namely 0.5° × 250 m. The precipitation products are currently disseminated in arrays of 1.0° × 1000 m spacing. Reflectivity from the NCAR S‐Pol S‐band radar (a radar with similar characteristics to the WSR‐88D) in east‐central Florida during the summer of 1998 were converted into precipitation estimates and collated with 1‐hour gauge accumulations collected from several high‐density rain gauge networks that were deployed simultaneously in the region. Radar‐gauge correlations were calculated for several degrees of spatial aggregation, ranging from 1.0° × 150 m to 1.0° × 900 m. Correlations were estimated from over 8000 radar‐gauge pairs, for both single points and areal averages. It appears that the degree of spatial aggregation of the radar estimates has little effect on radar‐gauge correlations.

Select this Article		Hydrologic Modeling for Assessing Climate Change Impacts on the Water Resources of the Rio Conchos Basin Eusebio Ingol‐Blanco and Daene C. McKinney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)496 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a hydrologic modeling application to assess climate change impacts on the water resources of the Rio Conchos basin, especially for agriculture and domestic water uses. The study basin is located in the Mexican State of Chihuahua, with a drainage area around 67,862 km2. It is one of the most important Mexican tributaries of the binational Rio Grande basin and contributes major water deliveries (about 55%) to US through the 1944 treaty between Mexico and the US. However, during period of drought, for instance in the 1990s, there has been conflict and competition for the water resources in the basin, and as a consequence Mexico accumulated an important water debt to the US. In addition, the hydrological behavior of the basin has recurrent periods of water stress, problems with long drought periods, allocation and release, and water pollution. Under this reality, it is important to evaluate and predict the available water resources in the next 50 or 100 years taking account of possible climate change impacts in the basin as well as assessing the policies to be implemented in order to face drought periods and preserve the agreements treaty between Mexico and the US. For this purpose, the Water Evaluation and Planning (WEAP) model is used. The model was calibrated and validated comparing the simulated flows resulting from the input of climatic time series with naturalized flows. Monthly climate time series from 1980–1999 (20 years) were used and some soil parameters were adjusted for calibration. Also, comparisons between simulated and naturalized flows were performed for different stations. In addition to this, calibration considering all water management infrastructures, such as, reservoirs, operation rules, canals, and diversions, was also carried out. The results show good correlation between simulated and observed flows which indicates that the model reproduces the hydrologic behavior of the basin, including, natural and historical flows, storage in reservoirs, water supplies, and water demands for agriculture and urban activities.

Select this Article		Hydrological Feasibility of Environmental Flows in the Rio Grande/Bravo Basin Samuel Sandoval‐Solis and Daene C. McKinney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)497 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Due to high water demand, the scarcity of water resources, and the complexity of water allocation in the Rio Grande/Bravo basin, environmental flows have not been considered as an integral part of the water management in this basin. Important environmental habitats such as the Big Bend National Park in the US, the Northern Chihuahuan desert, the Maderas del Carmen and the Cañon de Santa Elena natural reserves in Mexico are ecologically threatened because of the lack of environmental water management policies in the basin. Several efforts have been undertaken by government agencies and non‐governmental organizations in order to determine the environmental flows requirements for the basin. Even though environmental flows in several locations along the basin have been determined (e.g., the Rio Conchos tributary), the quantification and availability of the water necessary to provide these environmental flows has not been determined. In this paper we evaluate the hydrological feasibility of environmental flows in the Rio Conchos tributary to the Rio Grande. This evaluation is done in a basin model constructed in the Water Evaluation and Planning system (WEAP) software. An analysis of the available water has been defined to determine the amount of water required to provide the environmental flows. The description and evaluation of the environmental flows are presented along with a comparison against the current water management policies.

Select this Article		Impacts of the Upstream Storage Reservoirs on Itaipu Hydropower Plant Operation Mario T. L. Barros, Renato C. Zambon, João Eduardo G. Lopes, Paulo S. F. Barbosa, Alberto L. Francato, and William W.‐G. Yeh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)498 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents some results related to the operation of the Itaipu hydropower plant. Itaipu is one of the largest hydropower plants in the world. It is a binational undertaking run by Brazil and Paraguay at the Paraná River on the border section between the two countries. Each country owns 50% of the installed capacity (14,000 MW). This study evaluates the impacts of the upstream storage reservoirs on the hydropower production of Itaipu. The analysis involves a system of 55 hydropower plants. Itaipu hydropower plant operates as a run‐of‐river reservoir and itself does not have storage capacity. However, there are many upstream storage reservoirs located in Brazil. The analysis is conducted using the HIDROTERM decision support system (DSS), which is basically an optimization model. HIDROTERM is designed for the management and operation of large hydrothermal systems. In its formulation the hydro plants are considered individually and the thermal plants are aggregated into subsystems. The optimization model is capable of handling different types of constraints, such as water transfers, multiple purposes and environmental requirements. Its objective function is to produce energy at a minimum cost. HIDROTERM integrates a database with basic information (hydrological and technical) to run the model and an interface to manage input and output data. The optimization model is written using the General Algebraic Modeling System (GAMS) package and so it can run with different nonlinear programming (NLP) routines. The results from the analysis show that the upstream reservoirs located in Brazil have significant impacts on the hydropower production of Itaipu.

Select this Article		Inflow Forecasting for Real‐Time Reservoir Operation Using Artificial Neural Network Taesoon Kim, Gian Choi, and Jun‐Haeng Heo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)499 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Artificial neural network (ANN) is used for inflow forecasting of reservoir up to the next 12 hours. Numerical weather forecasting information (RDAPS), recorded rainfall data, water level of upstream dam and stream gauge site, and inflow of the current time are employed as input layer's training values, and target value is +3, +6, +9, and +12 hours later inflow to Hwacheon reservoir in South Korea. Comparison result between ANN with RDAPS and without RDAPS shows that RDAPS information is useful for forecasting inflow of reservoir.

Select this Article		Integrated Management of a Finite Water Supply in the Desert Daniel Wendell, Steve Shultz, and Aditya Tyagi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)500 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Fort Irwin is located in California's Mojave Desert, adjacent to Death Valley, and receives about five inches of rain per year. Local water supply comes from three separate groundwater basins that have no significant natural recharge and therefore provide a finite supply of water. The base is an important Army training facility and extending the life of water supplies is of critical importance. This work was undertaken to maximize the “lifespan” of local water supplies, minimize costs, and avoid adverse impacts to the extent possible. To meet the needs of this project, the entire water cycle of the area was evaluated in an integrated and quantitative manner, including: modeling local groundwater supplies; evaluating potential development of remote water supplies and associated costs; conducting an end‐use water demand and conservation analysis; developing a recycled water irrigation program; implementing an indirect wastewater reuse (i.e., recharge) program; developing an operations program designed to mitigate adverse impacts such as land subsidence; and assessing cost, power consumption, and greenhouse gas emissions from the various alternatives.

Select this Article		Long‐Lead Forecasting of Monthly Rainfall Using Large Scale Climate Signals and Statistical Disaggregation Models Azadeh Ahmadi, Mohammad Karamouz, Sara Nazif, and Navideh Noori ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)501 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Monsoon, one of the most dynamic climate systems, controls rainfall variation in some countries in Asia such as India, Bangladesh, Pakistan, and Iran. It delivers the main component of annual rainfall in these regions. In this study, the relationship between Iran monsoon rainfalls and some large scale climate signals such as SLP (Sea Level Pressure) and SLP differences over certain effective regions have been examined. The correlation coefficient between various combinations of climate signals with the rainfall at different time lags demonstrates some significant correlations which are used to identify the predictors for the rainfall forecasting. In this paper, a fuzzy rule model has been developed to predict the six‐month rainfall in the southeastern part of Iran. Then the long‐lead forecasting rainfall is disaggregated to a monthly scale using statistical disaggregation models and by considering the historical share of each month from total 6 month precipitations. In real time, the predicted value of each month during the 6 month time horizon is modified once the observed precipitation in any of the prior months becomes available using the Bayesian Theory. This way the accuracy of prediction will be significantly increased as we approach the last 3 months of the forecast period. The proposed model makes adequate lead time for estimation of the water resources potential for mid‐term planning. Since the planning scale of water resources planning is usually monthly, disaggregated rainfall could increase the accuracy of operating schemes in the study area.

Select this Article		Looking for a Solution — Joint Front Range Climate Change Vulnerability Study Alfredo Rodriguez and Laurna Kaatz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)502 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes ongoing efforts by Colorado's Front Range water providers to assess changes in the timing and volume of hydrologic runoff that might be expected from selected climate change scenarios for the years 2040 and 2070. Many utilities across the United States believe that climate change poses a threat to their water supplies, and have a desire to evaluate potential impacts. This cooperative research will provide water utilities in the Rocky Mountain Front Range with the knowledge and methodology necessary to evaluate potential climate change impacts on their water supplies. Furthermore, this study will set the stage for future advances in procedures and technologies.

Select this Article		Managing Salinity in the Upper Santa Clara River System of California Nathan Brown, Brian Louie, Frank Guerrero, Terry Foreman, Sorab Panday, Vivek Bedekar, and Jagjit Kaur ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)503 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Santa Clara River in Southern California provides beneficial uses that include agricultural water supply, groundwater recharge, and rare and endangered species habitat. Significant urbanization has contributed to elevated chloride concentrations along portions of the river in the Santa Clarita Valley and downstream areas. The affected reaches of the Santa Clara River are included on California's list of impaired waters with respect to chloride. A total maximum daily load for chloride, which was originally adopted by the Los Angeles Regional Water Quality Control Board in 2002 and later amended in 2004 and 2006, required special studies to provide the technical basis for establishing appropriate chloride water quality objectives. As part of these studies, a fully integrated groundwater/surface‐water numerical model was developed to facilitate the implementation of the chloride total maximum daily load. Modeling results indicated that implementation of expensive water treatment alternatives at two water reclamation plants would not likely lead to consistent compliance with existing chloride objectives in local streams or underlying groundwater basins. Accordingly, the model was used to develop a cooperative alternative water resources management approach. Once implemented, this approach could protect beneficial uses, aid in managing salinity (specifically chloride concentrations) in the Santa Clara River system, improve salt exportation from the study area, and provide enhanced water‐supply benefits to water users in affected areas, while providing flexibility and more feasible chloride compliance solutions.

Select this Article		Modeling Techniques to Incorporate Low Impact Development Features into Detention Analyses Kristin White, P.E., CFM, LEED AP and Jennifer J. Walker, P.E., CFM ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)504 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Developments that include Low Impact Development (LID) features or integrated management practices (IMP)s can achieve both storm water quality and quantity benefits. The greatest quantity and quality benefits may be achieved when the site is designed with a holistic approach to LID from the beginning. To maximize the benefits of the LID features, it is often beneficial to integrate the volume and infiltration capacities into the detention analysis. This paper examines various modeling techniques to incorporate IMPs into detention analyses. Simplistic analysis as well as complex modeling techniques are included.

Select this Article		MOPSO in Multipurpose Operation of Single‐Reservoir System E. Fallah‐Mehdipour, O. Bozorg Haddad, and M. A. Mariño ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)505 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Complexity of engineering problems, especially in the field of water resources, makes traditional optimization tools less efficient and enhances the popularity of evolutionary algorithms. Traditional optimization methods present just a single point as the optimal solution even in multi‐objective problems. Thus, the main necessity to apply evolutionary algorithms is to present a set of nondominated solutions/Pareto‐fronts as the optimal/near‐optimal solutions, whereas most of problems in the field of water resources management are considered as a compromise between several objectives. In this paper, the Multi‐Objective Particle Swarm Optimization (MOPSO) is applied to the operation of a multipurpose reservoir system. The objectives are: (1) maximization of reliability; (2) minimization of vulnerability; and (3) minimization of resiliency of the reservoir system, satisfying the downstream demand. The proposed algorithm is compared to a traditional method (weighting method). Results show that the MOPSO algorithm is successful in finding near‐optimal, Pareto‐front solutions.

Select this Article		Multi‐Criteria Decision Making under Uncertainty in Rainfall‐Runoff Calibration: A Fuzzy Compromise Programming Approach Based on Alpha Level Sets M. Shafii and F. De Smedt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)506 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper involves a methodology developed for multi‐criteria decision making and to reduce the number of Pareto optimal solutions. The technique is a Fuzzy Compromise Programming (FCP) coupled to a Genetic Algorithm (GA) applied for a case study on multi‐objective rainfall‐runoff calibration. The uncertainty associated with probable preferences of decision‐makers has also been dealt with by the fuzzy extension principle and alpha‐cut levels (i.e. considering the importance of the criteria by triangular fuzzy weights). The problem, therefore, becomes to solve a set of non‐linear programming problems using GA, which results in ranking the alternatives based on a distance metrics. The obtained results show that the proposed hybrid FCP‐GA approach performs well as a means to sieve among the Pareto optimal parameter sets of the problem. It would also help to choose the most preferable solutions, especially in cases where one is obliged to give a limited number of best solutions.

Select this Article		Multiobjective Differential Evolution and Differential Evolution for Irrigation Planning Piyush Gupta, A. Vasan, and K. Srinivasa Raju ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)507 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The present paper discusses the applicability of Multiobjective Differential Evolution (MODE) and single objective Differential Evolution (DE) to a case study of Mahi Bajaj Sagar Project, Rajasthan, India. Three objectives, namely, net benefits, agricultural production and labour employment are analyzed in the multiobjective framework using MODE. Four variations (strategies) of Differential Evolution, namely, DE/rand/1/bin, DE/rand/1/exp, DE/best/1/bin and DE/best/1/exp are explored. Population size, crossover and mutation probabilities and number of generations are the parameters that are required as input to MODE. In order to have a better insight on the performance of the strategies, DE in single objective framework is also employed with the same four strategies for all the three objectives with the above settings. In addition, a comparative analysis is also made for all the four strategies in both single and multiobjective framework.

Select this Article		Multireservoir Simulation Using Multipurpose Constraints and Object‐Oriented Software Design Marcelo A. Cicogna, Darrell G. Fontane, Ieda G. Hidalgo, and João E. Lopes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)508 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The hydroelectric short term planning is quite challenging in order to respect all the operational restrictions concerned with hydropower generation. A detailed simulation model combining multipurpose constraints and object‐oriented software design is presented for short term decision support. The object‐oriented design permits a mathematical structure that divides the decisions tasks from the regular hydroelectric computation. The main operational policy allows users to validate a hydro generation schedule towards an inflow forecasting. In other words, the simulator can accept hydro generation as data input and convert it to water flow variables (turbines discharge and spillage), using the inflow forecast and the initial reservoirs storage. The water balance equation, hydro generation and efficiency calculation modules are synchronized with the state‐of‐the‐art of multireservoir operation. As an important result, this simulator can automatically correct the input data of the operational policy, saving substantially time into decision‐making process. A test problem on 94‐reservoir from Brazilian Integrated Hydropower Generation System was simulated over an hourly one‐week horizon with fine performance, evidencing the simulation model capabilities against large scale hydropower operation problem.

Select this Article		Nonlinear Dependence in Hydrologic Time Series H. S. Kim, B. Sivakumar, and E. T. Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)509 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Studies investigating the chaotic nature of hydrologic processes commonly employ the correlation dimension method. Although this method is generally reliable, it may also have some limitations, influenced by a host of factors. One such factor is the delay time for reconstruction of the phase‐space to represent the underlying dynamics. There is also an increasing realization that fixing the delay time window rather than just the delay time itself may be more appropriate. An attempt is made in this study to test the C‐C method towards fixing the delay time window and assessing the nonlinear and chaotic dynamic characteristics of hydrologic time series. Three data sets are studied: daily flow from St. Johns River, Florida; biweekly volume from the Great Salk Lake; and daily rainfall from Seoul. The results from this method are also compared with those obtained using the autocorrelation function method.

Select this Article		Paleo Pacific Ocean Sea Surface Temperature Variability and Upper Colorado River Basin Streamflow Oubeidillah A. Aziz and Glenn A. Tootle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)510 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A study of the influences of Paleo Pacific Ocean Sea Surface Temperature (SST) variability and water‐year Upper Colorado River Basin (UCRB) reconstructed streamflow is presented. Reconstructed streamflow data is available from several sources in the UCRB. The proxy records (streamflow) are derived from tree ring chronologies and these streamflow reconstructions provide an effective way to analyze patterns of variability (including drought) over a period of time extending beyond any instrumental record in UCRB. Yearly proxy and coral based Pacific Ocean SST reconstructions, consisting of five by five degree cells, are available from 1590 to 1990. The range selected for the study is from Latitude 20° South to 60° North and 120° East to 80° West and 40° West to 2° West. A “lag” analysis is performed such that the SST dataset is for the year prior to the streamflow dataset. Additionally, epochal variability of climate signals [e.g., El Niño‐Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO)] will be examined to determine if ENSO or PDO has strengthened (or weakened) over time. The Singular Value Decomposition (SVD) statistical method has been identified as the preferable statistical method to identify coupled relationships between two, spatial‐temporal fields. While SVD has been applied to SSTs and various hydrologic variables (e.g., Palmer Drought Severity Index — PDSI, precipitation, streamflow), this represents the first such application to reconstructed (paleo) datasets. The use of SVD with Pacific Ocean SSTs eliminates any spatial bias as to which SST region (or regions) may impact streamflow. This will assist in the identification of a SST region (or regions) that may not be represented in existing Pacific Ocean climate variability (e.g., ENSO, PDO) and could display the impacts of climate change.

Select this Article		Planning for Climate Change John A. Kliem, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)511 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Climate change is upon us. Models used to predict climate change lack the granularity to allow communities to be accurately predicting the impacts of climate change. Federal Funding of Climate change research can barely keep pace with inflation much less provide the research required for local communities to develop climate change plans. Local governments need to develop a strategy to resource the modeling of climate change for their community. Regions could band together to source the modeling or solicit help from their congressional representatives. Next, leaders need to develop an action plan that addresses possible impacts to the community's industrial base or other natural resources.

Select this Article		Probabilistic Streamflow Forecasts Based on Hydrologic Persistence in Central Texas Wenge Wei and David W. Watkins, Jr. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)512 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In many cases, streamflow persistence (month‐to‐month or season‐to‐season correlation) can be used in place of climate forecasts to provide useful forecast information to water managers. In this study, an ordinal polytomous logistic regression model is proposed to generate tercile probability stream flow forecasts (i.e., probability of low, medium, and high categories) based on persistence for the Lower Colorado River system in central Texas. Forecast performance is evaluated by cross‐validation using the Brier skill score (BSS) and the Ranked probability skill score (RPSS). The results show that stream flow persistence can provide significant forecast skill during the winter and spring seasons, when water allocation decisions are being made for the coming summer growing season.

Select this Article		Providing a Physical Basis for Statistical Homogeneity in Regional Frequency Analyses Fredline Ilorme and Veronica W. Griffis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)513 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract To estimate the magnitude and frequency of flood flows at ungauged sites, space is traded for time using a regional frequency analysis. This requires the delineation of homogeneous regions in which the flood regime is sufficiently similar to allow the spatial transfer of information to ungauged sites. However, the ability to do so with adequate precision is hindered by our limited knowledge of the physical properties and mechanisms that produce flood flows. In addition, the actual delineation of regions is highly dependent on the similarity measures and classification techniques employed. It is generally accepted that similarity in the flood regime is indicated by similarity in basin characteristics, and thus these basin characteristics can be used to delineate regions and to classify ungauged sites. However, recent evidence suggests this is not the case. The objective of this research is to evaluate whether or not regions which are statistically homogeneous are also physically homogeneous. Preliminary results using data for 480 sites in the Southeastern U.S. are presented in this paper. Multivariate statistical methods were employed to delineate regions based on physical basin characteristics and at‐site flood statistics. The delineated regions were then assessed from both a physical and statistical viewpoint.

Select this Article		Reducing Uncertainty of Continuous Streamflow Predictions in Ungauged Basins (PUB) Using Regional Constraints: Using Regional Constraints for PUB T. Wagener ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)514 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Our environment is changing rapidly in many regions of the world, with often‐significant implications for current and future water resources. Disturbances to the current environmental system include land cover change, and the increasing impacts of a changing climate. The potential of developing successful strategies to respond to these changes lies in our capacity to anticipate their impact. One important question in this context is the potential change to streamflow characteristics at the watershed scale. However, most watersheds in the US and elsewhere are ungauged, leading to large uncertainty in our hydrological predictions to establish benchmarks, which are often the basis for the development of water resources management strategies. How can we obtain a reliable and continuous spatio‐temporal picture of regional environmental status, trends and long‐term projections to identify information gaps — and thus monitoring needs — and likely hot spots and hot moments where for example critical ecosystem thresholds are exceeded or will be exceeded in the future? This paper presents a methodology to formalize regional information on streamflow characteristics using a Mixture of Gaussians approach, which provides constraints on continuous watershed simulations. US examples show how this approach leads to reduced uncertainty in continuous streamflow predictions for water management in ungauged basins and in terms of potential change impacts.

Select this Article		San Joaquin River Restoration Program Monitoring and Management Plans J. Payne and D. Mooney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)515 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The San Joaquin River is a prominent and important feature of California's Central Valley. Historically, spring runoff from Sierra streams would spread over a valley floor covered by marshes and seasonal wetlands. In 1942, Reclamation completed construction of Friant Dam, ceasing flow to some portions of the river and ultimately led to the extirpation of salmon runs in the San Joaquin. In 1988, a coalition of environmental groups challenged renewal of long‐term water service contracts to the CVP Friant Division contractors. On September 13, 2006, after more than 18 years of litigation, all litigants signed onto a Stipulation of Settlement. A significant challenge to the implementation of the Settlement will be creating an adaptive management plan for a river which has not provided a connected ecosystem in over fifty years. The monitoring plan discussed in this paper is being developed to assist in the adaptive management of the Settlement.

Select this Article		Selection of Overflow Control Strategies for the Austin Clean Water Program Joseph D. Smith and Eric D. Loucks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)516 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Austin Clean Water Program (ACWP or Program) was created in 2001 to assist the City of Austin in meeting the terms of a USEPA Administrative Order that required the City to address its overflow problems by 2009. With a database of more than two thousand defects and overflows, it was not immediately obvious how the City should proceed. The City and the Program were under significant time constraints with less than eight years available to establish a course of action and then design and build the needed improvements. This paper describes the decision making process used to identify the improvements included in the program. A flow down approach was employed to systematically identify the system deficiencies and associated remedies that were likely to accomplish the objectives of the Program. The final Program now consists of one hundred collection system rehabilitation, repair or replacement projects with a total cost of 350 million dollars.

Select this Article		Spatial Evolutionary Algorithms for Characterizing Large‐Scale Spatial Groundwater‐Vegetation Dynamics in Arid Region Jihua Wang, Ximing Cai, and Albert J. Valocchi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)517 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Vegetation in arid riparian zones heavily depends on groundwater, meanwhile the distribution of vegetation impacts the groundwater flow in the area. This study describes a methodology to characterize groundwater‐vegetation dynamics using a spatial evolutionary algorithm (SEA). It incorporates spatial knowledge of groundwater and vegetation to facilitate the optimal search of vegetation distribution compatible to groundwater flow. Unlike a regular EA for spatial models, the SEA employs a hierarchical tree structure to represent spatial variables in a more efficient way. Furthermore, special crossover and mutation operators are designed in accordance with the tree representation. In this paper, the SEA is applied to searching for the maximum vegetation coverage associated with a distributed groundwater system in an arid region. The results of computational experiments demonstrate the efficiency of SEA for large‐scale spatial optimization problems. Extension of the algorithm for other water resources management problems is discussed.

Select this Article		Study on the Water Value Conversion between Economy and Ecology and Countermeasures of Water Resources Distribution for Coordinated Development of Economy and Ecology Hongzhen Ni, Hao Wang, Bo Zhao, and Dangxian Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)518 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Taking Beijing as an example, the paper studies response mechanisms to water quantity and quality of economy and environment, calculates water value and studies the conversion law of water value, measuring the gains and losses of the water conversion between economy and ecology. On this basis of analysis, the paper tries to give some suggestions for water sustainable utilization. The example gives us some conclusions: (1) in Beijing 2000, the water value of economy is more than ecologic, and in the low level of life, the man could pay more attention to economic water use; (2)if 4.04 × 10⁹ m³ used by social economy in 2000 are reallocated between environment and economy, following utility maximum principle, 24.76 million m³ could be used by economy which is far less than actual, comprehensive water price is RMB 8.01/m³ which is more than actual price 2.81, present water price cannot promote water reasonable allocation and sustainable utilization.

Select this Article		The Implications of Discretizing Continuous Random Variables: An Example Using the U.S. Geological Survey Reporting Standards for Streamflow Data Stacey A. Archfield and Richard M. Vogel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)519 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract One of the most fundamental assumptions in statistical analysis is whether the random variable of interest is continuous or discrete. Natural processes such as streamflow are considered to be continuous random variables, able to take on an unlimited number of possible values. However, to reflect data accuracy, reported streamflow values are generally rounded. For example, the U.S. Geological Survey (USGS) reports mean daily streamflow values less than 1 cubic foot per second (ft³/s) to the nearest hundredth place (0.01), resulting in only 99 possible values for streamflows between 0 and 1 ft³/s available for statistical analyses. The limits of the data subsequently result in the discretization of a continuous variable; the effects of discretization on the statistical properties of the data could affect applications such as moment estimation, regional frequency analysis, and distribution fitting, particularly for low flows where rounding could substantially reduce the number of possible values. In an effort to determine the effects of discretization, large samples of independent data were generated from a generalized probability distribution to the sixteenth decimal place. The synthesized data was then rounded according to USGS streamflow‐reporting standards. Initial comparisons of the original synthesized data and the rounded data show that estimates of the sample mean and standard deviation only differed slightly. Additional experiments will explore the effects of rounded data in other statistical analyses as well as for autocorrelated data.

Select this Article		Uncertainty Analysis: You Need to Know What You Don't Know David T. Williams, Ph.D., P.E., CFM, D.WRE, F. ASCE, P.H. and Joseph D. Countryman, P.E., D.WRE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)520 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Many of the ideas presented in this paper have been around for numerous years. The main proponent of this approach for use in water resources subjects is the U.S. Army Corps of Engineers (COE) and it use is mandated for COE flood control projects. In the early 1990s, the COE and other entities re‐examined the concept of freeboard for their flood control projects and felt that the use of Risk and Uncertainty concepts would help quantify the additional required protection above the design elevation instead of adding a somewhat arbitrary value (NRC, 2000). This paper presents the concepts of Risk and Uncertainty Analysis (affectionately termed as RU) as applicable to floodplain management and issues. It also goes over some of the important aspects of RU analysis that should be understood by water resources engineers and floodplain managers. Within about 5 years, floodplain managers will be required to be knowledgeable on the subject of Risk and Uncertainty!

Select this Article		Uncertainty and Sensitivity Analysis for Models with Calibrated Parameters Seung Uk Lee and Jery R. Stedinger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)521 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Traditional measures of sensitivity in watershed modeling are based upon a framework wherein parameters are specified externally to a model, so one can independently investigate the impact of uncertainty in each parameter on model output. However, when parameter estimates results from a joint calibration to observed data, the resulting parameter estimators are interdependent and different procedures should be employed. For example, over some range, evaporation rates may be adjusted to correct for changes in a runoff coefficient, and vice versa. As a result, descriptions of the precision of such parameters may be very large individually, even though their joint response is well defined by the calibration data. These issues are illustrated with the simple abc rainfall‐runoff model. In fitting the abc model to data from the Pigeon River Watershed (North Carolina), our analysis explicitly accounts for rainfall measurement errors so as to adequately rpresent the likelihood function for the data given the major source of errors causing lack of fit.

Select this Article		Vulnerability of the Hydraulic Resources of the River Basin of the San Juan‐Brave River with the Global Climatic Change Rodríguez García José Luis and Cardoso Landa Guillermo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)522 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract All the countries are exposed the devastating consequences of the climatic change. For such reason it is necessary to implement political that not only they help to resist the phenomenon but that also help to adapt to the new climatic conditions and to diminish the vulnerability to extreme the climatic events such as droughts, floods, changes in precipitation regimes, among others. This global problem has local solutions. For the analysis and effects of this one phenomenon a region of the barren zone has been selected to the North of our country that is the river basin of the Bravo river, in where the pressures become more evident on the resource water due to different factors on the one hand from their shortage and on the other hand from the demand by the use of the water, situations that difficult the diverse uses of the water. Specifically the river basin of the San Juan‐Brave River was studied, that is a sub river basin of the river basin of the Bravo River.

Select this Article		Water Demand Forecasting for the City of the Future against the Uncertainties and the Global Change Pressures: Case of Birmingham K. B. Khatri and K. Vairavamoorthy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)523 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In order to ensure the adequate and sustainable water management for the city of the future, the impact of the global change pressures and sources of uncertainties should be analyzed appropriately. This paper presents a model for forecasting the future water demand addressing the uncertainties associated to the climate change, population and economic growth. It uses the historic time series records of water consumption for forecasting the future water demand, and applies the Monte Carlo sampling, Latin hypercube sampling and bootstrap methods to describe the associated uncertainties. The model was applied in Birmingham, UK to analyse the water demand for year 2035. Results showed that future water demand in Birmingham will be governed by the socio‐economic factors not by the climate change impact. There is a very high likely risk of not meeting the future water demand from the existing supply sources.

Select this Article		Water Quality Effects of Varying Crop, Fertilizer and Carbon Prices T. L. Ng, J. W. Eheart, and X. Cai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)524 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Crop and fertilizer prices have increased dramatically in the past few years. These prices, together with existing demand for carbon trading allowances, affect farmers' decisions. It is useful to assess the effect of varying crop, fertilizer and carbon prices on farmers' decisions, and in turn, the effect of these decisions on surface water quality, specifically the nitrate load from the watershed. To achieve the objectives of this study, a mixed integer optimization model incorporating a hydrologic model of a test site is developed. The Salt Creek watershed in East Central Illinois has been selected as the test site for this study. Simulation results indicate that there is a higher tendency for farmers to produce corn in 2007 and 2008 than in previous years. Consequently, the average fertilizer use in that period is relatively high, causing greater levels of nitrate runoff. Results also indicate that at current carbon prices, carbon trading is ineffective in reducing nitrate runoff.

Select this Article		Water Resources Planning under Non‐Stationary Hydroclimate in a Snow Dominant Watershed Francis I. Chung, Tariq N. Kadir, and Jefferey K. Galef ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)525 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Milly et al. in a recent article (Science, Vol319, 1February, 2008, pp573–574) declared that “stationarity is dead and should no longer serve as a central, default assumption in water‐resources risk assessment and planning.” They went on stating, “Finding a suitable successor is crucial for human adaptation to changing climate.” Noting that the fundamental cause of this climatic change is the warming temperature and further noting no apparent change in the runoff volume for the last century, the authors hypothesize that a temperature based hydrology can explain most of the non‐stationary behavior of the runoff in a snow dominant watershed like the Upper Feather Basin in California. The observation of the historical temperature data suggests that this region is warming consistent with the global trend. The projections of precipitation by various GCM's are wide spread and uncertainties on the wetness (or dryness) abound whereas the future temperature projections, through also widely spread, are unanimous in directional sense—going up or getting warmer over time. Noting this robust nature of the future temperature projections and also noting that the cause of the future precipitation changes between rain and snow is due to the rising temperature, the authors take an approach that the temperature, rather than the precipitation, should be the commencing point in the development of the changing future hydrology. We claim that the main cause of the “death” of the stationarity in a snow dominant watershed may be the warming temperature. Therefore, by commencing with the temperature in the hydrologic process, either the form of precipitation or the melting of the accumulated snow can be simulated and the non‐stationary aspects of the future hydrology can be captured for more adequate water resources planning and management. The USGS under a contract to the California Department of Water Resources completed development of the Precipitation‐Runoff Modeling System (PRMS) application for simulating daily streamflow for the Upper Feather River Basin. PRMS simulates all the major snowmelt/precipitation related physical processes including snowpack accumulation/melting, sublimation, evapotranspiration, surface runoff, subsurface flow, and ground water flow. The calibrated model simulates Water Years 1971–2001. This analysis perturbs the historical period daily minimum and maximum temperatures by 1°C, 2°C, 3°C, and 4°C, respectively, to determine the impact on snowmelt/runoff processes and ultimately streamflow at Oroville; all other parameters were unchanged from the historical simulation (Base Case). Precipitation spatial and temporal distribution was unchanged. Model output parameters studied include evapotranspiration, groundwater flow, groundwater recharge, interception evaporation, precipitation (rain/snow), runoff, snow cover percent, snow evaporation/sublimation, snowmelt, snowpack water equivalent, surface streamflow, subsurface flow, and subsurface recharge. For these varying degrees of warming, the outflows of the Basin were examined and compared to the base historical simulation. The timing of the center of the mass, the April through July runoff as a percent of the annual runoff, and the April snowpack water equivalent are shown to change appreciably with rising temperature.

Select this Article		Water Supply and Energy Generation L. K. Lampe, L. M. Adams, and D. G. Jensen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)526 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Energy and water resources are inextricably linked: the production of energy requires large volumes of water; and reciprocally, the treatment and distribution of water relies on available, affordable energy. This paper reviews technology trends, identifies regulatory and technical challenges to the electrical energy industry, provides case studies based on work by Black & Veatch that explores methods for the sustainable provision of energy and water to communities, and discusses the ongoing research and development efforts as related to utilities and regional stakeholders.

Select this Article		Watershed Management in the Indian Himalayan Region: Issues and Challenges Samagra Rana and Vaibhav Gupta ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)527 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Indian population constitutes about 15 % of the world's population, whereas its land area and water resources are about 2 % and 4 % of the world's total, respectively. In the last 50 years, the per capita availability of fresh water has been reduced by about 90 %, and the same trend is still going on with the increase in population, urbanization, and industrialization. At the national level, the irrigation alone consumes about 83 % of the available water resources. About 30 % of the total geographical area is drought prone due to erratic pattern of rainfall and out of about 148 million hectare cultivable land about 72 % is rain fed. The economy of the Himalayan region is predominantly agrarian. More than 4/5th of the working population is directly engaged in agriculture. Though Himalayan region gave birth to several perennial rivers and streams, the inhabitants face the problems of drinking water and irrigation. Even though only 12.5% of the total land area is under agriculture, only 11% of the cultivable area is irrigated, almost 64% of which is fed by natural springs. The topography of the region is steep; the average annual rainfall is high (1200–1600 mm) and the soils range from sandy to sandy loam causing very high percolation losses of rainwater from individual farmers' terraced fields. The soil does not hold water for long and consequently in the absence of available soil moisture, the crops suffer badly due to moisture stresses at different stages of crop growth during post‐monsoon period. About 60% population in hilly region depends on natural water springs to fulfill their day to day water needs for drinking, sanitation, irrigation etc. About half of the perennial springs have either dried‐up or have become seasonal due to ecological imbalance and environmental degradation during last two decades. Nearly 8000 villages mostly located in upper and mid hills have been facing acute shortage of drinking water.

Select this Article		Whatever It Takes from Water Availability Model to Cost of Water Alfredo Rodriguez ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)528 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes ongoing efforts by the Water Resources Division at Aurora Water to determine the cost of Raw Water for the City of Aurora. Aurora is currently developing, at a cost of approximately 700 million dollars, a new water supply and delivery system, the Prairie Waters Project (PWP). This project will act as an additional source of water supply. The project is designed to divert Aurora's reusable return flows from the lower South Platte River, pump them back to the City, and, after suitable treatment, reintroduce them into the City's potable water system. In addition, Aurora Water staff is diligently pursuing the acquisition of storage and agricultural water rights in the South Platte River north of the Denver Metropolitan Area. Purchased agricultural water will be transferred to municipal use to supplement reclaimed water in order to provide for future population growth. Using results from the water availability model, and established budgeting procedures, staff at Aurora Water is taking the necessary steps to determine the cost of raw water.

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STUDENT AUTHOR COMPETITION WINNERS

Select this Article		Current Water Management Practices and the Effects of Climate Change on the Colorado River Basin J. Brandon Klenzendorf, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)529 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Colorado River Basin (CRB) reservoir system is one of the most over‐allocated systems in the world. Due to recent drought conditions within the past decade, reservoir storage has been decreasing and shows no sign of increasing in the near future. The allocated demands from the system are greater than the average streamflow into the system. Furthermore, it is expected that climate change will only make the situation more severe in the near future. Various modeling techniques show that climate change will decrease precipitation in the CRB while increasing evaporation. This combination results in decreased runoff and streamflow which provides the majority of water in the CRB. However, the more significant problem is the over‐allocation of the river. The allocations and water usage can be controlled much easier and have a much greater impact on the reliability of the reservoir system than global climate change. This paper will highlight some of the major flaws in the water allocations utilized in the CRB and reasons for mistakes made in the past. Previous studies on the reliability of the CRB reservoir system are investigated, and the general impacts of climate change on the hydrologic cycle are briefly discussed.

Select this Article		Does Polymer Have an Effect on Bacterial Regrowth in Anaerobically Digested Biosolids? Jean M. Ryan, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)530 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Recently more attention is being given to the regrowth of bacteria in treated biosolids. It has been found that in many anaerobically treated biosolids, bacterial regrowth occurs between digestion and the point in which the biosolids are disposed of or used for land application. This experiment examines the possible effect of polymer usage on bacterial regrowth in anaerobically digested biosolids. In order to examine this possible effect, a control sample, a sample with newly‐reconstituted polymer, and a sample with pre‐constituted polymer (several days old) were compared for their effects on bacterial regrowth using an MPN test. Each sample was 300mL, and a weight ratio of 1mg: 185kg, assuming 2% solids, was used to add polymer to all of the samples, excluding the controls. These samples were then compared at 0, 1, and 2 days of incubation. As a whole, the MPN values increased with one and two days of incubation at room temperature. However it was also found that the control samples had a higher MPN than the samples treated with the old and new polymer after one and two days of incubation, which suggests that polymer does not have an effect on the increase of fecal coliforms in biosolids.

Select this Article		Effect of Acid Mine Drainage on Aluminum Release from Clay Minerals Oscar Vazquez, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)531 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Aluminum is an environmentally toxic material found in some acid mine drainage (AMD) locations. Data reported from over 150 different mine drainage samples across USA showed that over 30% of these locations presented minimum dissolved aluminum concentrations of 50 mg/L, elucidating that aluminum pollution must be taken seriously. Research underway at the University of Pittsburgh involves an AMD site where a former trout fishery stream has been ruined. The evolution of the aluminum in this AMD, released from a subsurface environment, suggested a first stage dominated by first order kinetics of exchange reactions on clay surfaces, followed by a second stage dominated by dissolution processes with lower rates that exist over a long term. Results from a batch experiment involving synthetic AMD and kaolin minerals were in concordance with this analysis.

Select this Article		Sensitivity Analysis of HEC‐HMS Hydrologic Model to the Number of Sub‐Basins: Case Study Osama Z. Al‐Hamdan, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)532 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a sensitivity analysis of the hydrologic model HEC‐HMS to the number of sub‐basins for the McDonald Creek watershed in Huntsville, Alabama. ArcGIS was used to estimate the parameters needed for the model. The sensitivity analysis of HEC‐HMS runoff results was evaluated for two cases, namely, Case 1 and Case 2. The number of sub‐basins of the watershed was 3 and 5 for Case 1 and 2, respectively. This study implements kinematic wave method to model the overland flow transform and Muskingum‐Cunge method for channel routing. The loss rate was estimated using both Green‐Ampt and SCS curve number methods. The results demonstrated that the number of sub‐basins did not significantly affect the discharge results. However, increasing the number of sub‐basins changed the discharge peak values. The results also showed that HEC‐HMS model was sensitive to the input slope parameter when the SCS method was used, while it was not in case of using the Green‐Ampt method.

Select this Article		Study of Low Dosage Pre‐Ozonation on Sand Filtration Efficiency Walter Lee Ellenburg, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)533 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The most traditional method for water filtration is the sand filter. Sand filters consist of sand, some type of activated carbon, and a more coarse aggregate such as gravel. Particles too large are then filtered out. Suspended particles too small for sand to catch are thus the problem, therefore different techniques are used to increase the efficiency of sand filters, these techniques are called pre‐filtration. The goal of pre treatment is to coagulate, or clump together; the small suspended solids so that they may be caught in the filter. Current water treatment plants use many different types of pre‐filtration: ferric, aluminum salts, or cationic polymers. One form of pre‐treatment is ozonation. By electrically charging oxygen and allowing a third molecule to join, ozone, (O₃), is created. Ozonation is the process of applying ozone to cause the small suspended particles in a given sample to coagulate. It has been studied and experimented for many years, proving a significant increase in coagulation and thus allowing the sand filtration to be more effective. As longer treatments of ozone are applied, the taste and odor may also be neutralized. In addition to the benefits previously stated, ozone may also be used as a disinfectant. In fact ozone oxidizes thousands times faster than that of chlorine. However, the production of ozone is somewhat energy intensive, and therefore an option that is sometimes over looked.

Select this Article		The Dubai Palms: Construction and Environmental Consequences Ethan Poole, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)534 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Virtually every western news agency and even the Discovery Chanel have produced ever growing pieces about the engineering accomplishments of the small Middle Eastern country of The United Arab Emirates (UAE). In an attempt to create tourism, Dubai, UAE, has created some impressive structures, but now, it is creating land itself. Five artificial islands are being reclaimed from the Persian Gulf — one of which, the Palm Jumeirah, takes the shape of a date palm, and will be the focus of this paper. Reaching several hundred meters into the gulf, and standing several above the water line, the Palm Jumeirah is so large it can be seen from space. While an impressive creation, a reclamation project of this size could easily have a negative effect on the environment. Upon researching the project, it became clear that the UAE was in such a rush to build the islands that the proper planning and environmental studies were not conducted, thus resulting in the destruction of the Persian Gulf's eco‐system. While most projects do tend to negatively effect the surrounding environment in some form, the islands, due to their shear size, have completely destroyed an already fragile eco‐system in a manner that may be irreversible. After introducing the reader to some basic information regarding the construction of Dubai's Palm Jumeirah, this paper will examine some of the major environmental effects that have occurred as a result of the Palm Jumeirah project.

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RETROFITTING STORMWATER BMPS

Select this Article		Developing Green Streets Prototypes to Reduce Combined Sewer Overflows for Cincinnati, Ohio Brian Marengo, Thomas Cahill, Daniel Wible, Courtney Marm, and Ralph Johnstone ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)535 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this study was to evaluate the feasibility of developing stormwater management retrofit demonstration projects for application in the public right‐of‐way (ROW) in form of “Green Streets.” This study responded a motion issued by the City Council of Cincinnati to create a plan for a Green Streets Pilot Project, targeting specific downtown streets for the implementation of methods to address stormwater runoff generated by the public right‐of‐way and to assess their feasibility to reduce combined sewer overflows. The study developed conceptual prototype stormwater controls to fit into common features in the public right‐of‐way and adjacent impervious features for four (4) street segments in the central business district of Cincinnati, Ohio. CH2M HILL's Low Impact Feasibility and Evaluation (LIFE) model was applied to evaluate each of the BMP concepts in terms of runoff reductions resulting from the planned level of storage, infiltration into the subsurface soils, and evapotranspiration. Cost estimates were developed to assess runoff reduction efficiency.

Select this Article		Implementation and Performance of Stormwater Best Management Practice Retrofits in Wilmington, NC J. D. Wright, W. F. Hunt, M. R. Burchell, II, C. A. Perrin, and E. R. McCoy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)536 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Burnt Mill Creek, located within downtown Wilmington, NC, is on the EPA's 303(d) list for impairment due in large part to urban stormwater runoff. The urban nature of the watershed presents challenges for restoration because of the varying land uses including single and multi‐family residential areas, recreational parks, and commercial and industrial areas. Restoration efforts are multiplying in Burnt Mill Creek as a result of passionate involvement from local community leaders, and partnerships with state organizations. The Watershed Education for Communities and Local Officials (WECO) coordinated a partnership, with NCSU BAE, the City of Wilmington, as well as several other key state and local organizations and citizens groups, to obtain an EPA 319 grant that addresses stormwater management in the watershed. Community involvement has led to several retrofit BMP opportunities, including pervious pavement and rain gardens at a local YMCA, two bioretention cells installed in the parking lot at Port City Java's corporate headquarters, a stormwater wetland in a city owned communal area, and several residential scale rain gardens in an urban low income community. Twelve rain gardens and twenty four rain barrels were installed at citizen's private residences in an urban neighborhood in downtown Wilmington. Although restoration takes time, momentum continues to build in the Burnt Mill Creek watershed as resources are devoted to thoughtful education and engagement with the public.

Select this Article		Modeling Stormwater Basins for Potential Retrofit Designs R. R. Headley and J. R. Wyrick ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)537 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Outflow structures for stormwater detention basins can vary widely within a single watershed. The designs are often left to the whim of the local engineer. Why should there be such differences? This research attempts to discern the performance and efficiency of various typical and atypical weir shapes. To accomplish this task, a scale model of a stormwater detention basin was constructed with removable outlet weirs. The physical model was calibrated using typical weir structures (e.g. rectangular, V‐notch, submerged orifice, etc.) in which accepted numerical models exist to calculate outflow discharge. Empirical stage‐discharge relationships were then calculated for the atypical weir structures (e.g. stepped notch, combinations of typical shapes, etc.). The atypical weirs simulated herein represent the range of outlet structure designs located in the Upper Mantua Creek watershed, Gloucester County, New Jersey. This area of New Jersey has experienced large urban growth in the past 40 years, and many of the existing basins were not designed for the current runoff volumes they experience. Within this 7.3 square mile watershed, there are currently 61 stormwater basins and more than 50 different outlet structure designs. The ability of each stormwater basin to pass or detain a given flow event can now be determined empirically. From these data, appropriate retrofit designs can be implemented.

Select this Article		Stormwater Infiltration Retrofits Experience Gained through Long Term Monitoring R. G. Traver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)538 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an overview of the experience gained through the design, construction and extended monitoring of multiple retrofit stormwater infiltration best management practices (BMP). Common design issues for retrofit infiltration BMPs include utilities, hydraulic inflow and outflow paths, and compacted urban soils. Assuming these constraints are addressed, the resulting project should work at least as well as any newly constructed BMP. The experience of long term monitoring of multiple BMPs allows the researcher to contrast performance and design features for both individual storms and seasons. Simply building new BMPs in a public setting introduces this concept to the professional community and the public. Findings from a suite of project reports, journal and conference proceedings, and student work is presented.

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STORMWATER RESEARCH I

Select this Article		A Tool for Determining Effectiveness and Whole Life Costs of BMPs C. C. Olson, L. A. Roesner, and B. R. Urbonas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)539 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the development of a tool that can be used to determine cost effective stormwater management strategies on a watershed scale, using various structural stormwater best management practices (BMPs). The tool is designed for application at the planning level and is simple enough to be used and understand by both technical and non‐technical personnel in the stormwater management field. With relatively few required user inputs, the tool estimates the following: 1) BMP effectiveness; reported in terms of the reduction of annual pollutant loading to the receiving water. 2) BMP whole life cycle costs; reported as the net present value of all costs incurred over the economic life of the BMP. and 3) BMP cost effectiveness, reported in terms of cost per mass of pollutant removed from the receiving water.

Select this Article		Controlled Full‐Scale Field Testing of an Up‐Flow Filtration Device Noboru Togawa and Robert Pitt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)540 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this research is to examine the removal capacities of a recently developed stormwater filtration device, in part developed by engineers at the University of Alabama through a Small Business Innovative Research (SBIR) grant from the U.S. Environmental Protection Agency. The UpFlo™ Filter is an efficient high‐rate stormwater filtration technology designed for the removal of trash, sediments, nutrients, metals and hydrocarbons from stormwater runoff. Compared with the traditional downflow filtration treatment, the upflow filtration method reduces clogging and was developed to remove a broad range of stormwater pollutants, especially those associated with particulates. The high flow rate capacities of the upflow filter are accomplished through controlled fluidization of the filtration media, while still capturing very small particulates through a flexible, but constraining, media container. The upflow filter also drains down between rain events which minimizes anaerobic conditions in the media and which also partially flushes captured particulates from the media to the storage sump, decreasing clogging and increasing run times between maintenance. Gross floatables are captured through the use of an angled screen before the media and a hood on the overflow siphon, while the sump captures bed load particulates.

Select this Article		The Observed Effects of Stormwater Infiltration on Groundwater M. D. Machusick and R. G. Traver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)541 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This research presents a case study of the impacts of stormwater infiltration on a shallow unconfined aquifer at a bioinfiltration BMP on the campus of Villanova University. The study site is a vegetated basin that with a 0.53 hectares drainage area consisting of parking areas and recreational fields with 35% directly connected impervious area. The study utilizes continuous monitoring of groundwater elevation, temperature and conductivity in conjunction with surface water hydrologic monitoring to assess the transport of conductivity and to examine the extent of groundwater mounding. Results indicate a direct impact on groundwater conductivity near the BMP, but also show significant attenuation compared to influent surface water. Following storms less than approximately 1.9 cm the upgradient control well presents larger increases in groundwater elevation, but for larger storms the well adjacent to the site displays increased mounding. Groundwater elevation monitoring indicates that the extent of groundwater mounding is related to infiltration rate and groundwater temperature. This study demonstrates the utility of groundwater monitoring for the purpose of BMP performance assessment. It is suggested that groundwater monitoring be considered for site monitoring plans and as a tool for BMP site selection.

Select this Article		Water Quality Assessed by Benthic Macro‐Invertebrates: Proposing the WQABI Method J. K. McNett and W. F. Hunt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)542 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Stormwater experts agree that the currently used percent removal methodology metric has many flaws, and some have suggested utilizing a BMP effluent concentration metric. This paper examines a new method that establishes effluent target concentrations for BMPs based on the health of macro‐invertebrates in the receiving water. 193 ambient water quality monitoring stations in North Carolina were paired with benthic macro‐invertebrate health ratings collected in very close proximity. Water quality for the sites ranged from Excellent to Poor and was divided into three distinct eco‐regions. Median NO₃ + NO₂, TKN, TN, and TP concentrations all increased with poorer benthic ratings; however, there was no such trend with respect to DO, TSS, and Fecal Coliforms. Overall, the new method was most effective in the Piedmont and Coastal eco‐regions; however with more data collection, the Mountain eco‐region may also benefit. For example, if regulators were to require “Good” water quality in the Piedmont eco‐region, designers would have to limit effluent concentrations of TN and TP would be 0.99 mg/L and 0.11 mg/L, respectively, per the method presented herein.

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STORMWATER RESEARCH II

Select this Article		A Robust and Fast Model for Simulating Street Flooding Arturo S. León, Leonardo S. Nanía, Arthur Schmidt, and Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)543 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This work is part of a long term project which aims to simulate (1) the hydrology, (2) street flows, (3) flow interception at inlets and (4) storm‐sewer flows in urban areas. The present work describes the application of the model using only the first two modules. The hydrologic model (first module) transforms rainfall to runoff using the kinematic wave approximation and simulating the infiltration process with the Green‐Ampt method. The street model (second module) is based on a finite volume‐shock capturing scheme that solves the full conservative Saint‐Venant equations and can be used to simulate subcritical and supercritical flows. The formulation of boundary conditions at the street crossings in the street model is general and can be used for any number of streets, any combination of inflowing and outflowing streets, and any flow type (e.g., supercritical flows). The model using the first two modules is fast and robust and it has several potential applications. Perhaps the most important one is that it can be used in new urban developments to identify critical zones of urban flooding (e.g., zones with high water depths and flow velocities) in order to take appropriate measures of drainage control (e.g., to increase capacity of inlets). This model can also be used in developed urban areas to locate the critical areas in case of inlet clogging. In order to illustrate the capabilities of the model (first two modules) it was applied to an urban catchment in the village of Dolton, a southern suburb of Chicago. The watershed of this village drains to the dropshaft CDS‐51 in the Calumet TARP (Tunel and Reservoir Plan) system which is operated by the Metropolitan Water Reclamation District of Greater Chicago. The fact that this model is fast makes suitable its application to large urban areas.

Select this Article		Evaluating the Mixing Mechanism of Outfall Discharges from Municipal Separate Storm Sewer Systems Michael H. Woo, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)544 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Under the National Pollutant Discharge Elimination System (NPDES) stormwater program, operators of large, medium, and regulated small municipal separate storm sewer systems (MS4s) require authorization to discharge pollutants under an NPDES permit. MS4s can be linear or complex, open, piped, manmade, natural, or a combination of all of the above. Some carry groundwater or piped streams, are tidally influenced, or have some other constant source of non‐stormwater discharge. An MS4 is not always just a system of underground pipes‐it can include roads with drainage systems, gutters, and ditches. Typically, an outfall from a MS4 discharges into a creek system and ultimately into a larger receiving water body which might or might not be tidally influenced. In order to evaluate the existing and expected water quality of the ultimate receiving water body, mathematical models are used to conduct flushing modeling and water quality modeling of the ambient waters. A hydrodynamic mixing zone model will be used to simulate steady or unsteady discharge from a single open channel outfall or a system of outfalls from municipal separate storm sewer systems (MS4s). This model is applicable for a wide range of hydrologic situations wherein flow and transport are governed by time‐dependent forcing functions. Permit requirements will consist of a Water Quality Monitoring Program to be implemented and samples collected according to permitting agencies' procedures for collection, control and preservation.

Select this Article		Physical Processes Resulting in Geyser Formation in Rapidly Filling Stormwater Tunnels Steven J. Wright, James W. Lewis, and Jose G. Vasconcelos ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)545 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A significant concern in the design of large, underground conduits for storm or combined sewer systems is the avoidance of geyser formation, a phenomenon which involves the explosive release of water through vertical shafts. Current practice for transient analyses of these systems involves application of numerical models to simulate the rapid filling processes. Since these models do not consider interactions between the inflows and air being displaced during the filling process, it is felt that these models cannot predict geyser formation. Data from a large diameter stormwater tunnel in Minneapolis, Minnesota has been analyzed to determine the events that led to a series of observed geyser events. Data include pressure and velocity measurements within the tunnel that can be correlated with a videotape of the geyser events themselves. The pressure records are inconsistent with hydrostatic pressure lifting water to the ground surface. Features of the pressure records can be interpreted to indicate the release of large air pockets through the dropshaft. A qualitative comparison of these results with smaller scale laboratory experiments indicates similarities in the pressure responses. These results suggest that the entrapment of large air pockets is an important component to the geysering process and that tunnel design procedures need to properly account for these effects.

Select this Article		The “Silver Bullet”: Proprietary BMPS and Metropolitan St. Louis Sewer District's Stormwater Program J. S. Hoskins and M. T. Buechter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)546 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In February 2006, as part of its Phase II Stormwater Quality Management Program, the Metropolitan St. Louis Sewer District (MSD) implemented rules that require post‐construction stormwater best management practices (BMPs) at development and redevelopment sites. MSD references the Maryland Department of the Environment's Stormwater Design Manual as a BMP design guide. However, this document does not specifically address proprietary BMP devices and currently there is not a national or Missouri state standard by which to evaluate them. For a proprietary BMP to be approved for use within MSD boundaries, the device's manufacturer must present it to MSD and request approval for one or more use levels. Possible use levels include General Use Level, Redevelopment Use Level, Highway Use Level, and/or Provisional Use Level. Submittal requirements and use level descriptions are provided in Proprietary Water Quality Products and the MSD's Stormwater Management Program (rev. Jan 2009), which can be downloaded from the MSD web site (www.stlmsd.com). Devices are approved for a particular use level based on (1) the treatment performance requirement for that use level and (2) the certified performance of the device. Performance certification testing must comply with the Technology Acceptance and Reciprocity Protocol (TARP) or the Technology Assessment Protocol‐Ecology (TAPE). When approved for use by MSD, each device is issued an approval letter that is posted on the MSD web site. Advantages of the process include (1) MSD recognition that the device is effective for its use, (2) manufacturers quickly ascertain whether their product can be approved, and (3) BMPs that meet requirements are approved in a reasonable time period.

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SECURITY ENHANCEMENTS IN WATER AND WASTEWATER UTILITIES 1

Select this Article		Survey of Water and Wastewater Utility Security Standards Dale Gabel, P.E., Yakir J. Hasit, Ph.D., P.E., and Yaron Ben Ari ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)547 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract A primary responsibility of water utilities is the protection of their water and wastewater infrastructure from significant threats created by natural disasters, malicious actions, and accidents. Following the events of September 11, 2001, water utilities placed additional emphasis on protecting their infrastructure from malicious threats, and security standards and guidelines were developed by various organizations across the world. A noteworthy set of guidelines was developed through the U.S. Environmental Protection Agency's (USEPA's) Water Infrastructure Security Enhancements (WISE) project, which was cooperatively executed by the American Society of Civil Engineers (ASCE), the American Water Works Association (AWWA), and the Water Environment Federation (WEF). In this project, both guidance documents that cover all aspects of water security (design, management, operations) and voluntary standards that cover physical security were developed. During the execution of this project a very thorough review of national and international guidances and standards was conducted. It was found that efforts by various organizations were at different stages of development and few, if any, had reached the stage of the WISE documents.

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SECURITY ENHANCEMENTS IN WATER AND WASTEWATER UTILITIES 2

Select this Article		Advances in Data Validation, Event Detection, and Communications Structures for a CWS: Case Study — Glendale, Arizona Kenneth A. Thompson, Rick Scott, Raja Kadiyala, Andreas Weingartner, and Joep van den Broeke ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)548 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Glendale, Arizona has been developing and implementing the various elements of a Contamination Warning System (CWS) since 2005. The purpose of the CWS is to provide multiple benefits to the utility through early identification of unusual water quality events, including those due to operational changes, occurring in the distribution system. The key to a successful CWS is the rapid analysis and evaluation of data from multiple sources to extract the relatively small amount of information related to the unusual occurrences in the distribution system. To effectively accomplish this, Event Detection System (EDS) software needs to have robust processes in place for both data validation and data analysis to enable accurate event detection. This paper provides an overview of the Glendale EDS and its capabilities for data validation and event detection.

Select this Article		Implementing a Contamination Warning System at a Department of Defense Facility: Case Study — Port Hueneme, California Kenneth A. Thompson, Steve Fann, Raja Kadiyala, Yakir J. Hasit, P.E., and Gary Jacobson, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)549 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The Naval Facilities Engineering Command, Engineering Service Center (NAVFAC ESC) in Port Hueneme, California is in the final stage of the development and implementation of a Contamination Warning System (CWS) Pilot Program, culminating a 3‐year effort. The purpose of the pilot program is to demonstrate the multiple benefits associated with a CWS, and it will serve as a model for other Department of Defense facilities. The CWS will include real‐time online water quality monitoring (OWQM) stations at multiple locations in the water distribution system. The OWQM stations will provide continuous data for pH, chlorine residual, turbidity, conductivity, total organic carbon, dissolved organic carbon, and ultraviolet/visual spectral imagery (200 to 700 nm). OWQM technologies that will be evaluated as part of the pilot program include the s∷can spectro∷lyzer™, s∷can ammo∷lyzer™, the Analytical Technologies (ATI) Water Quality Panel (for pH, free chlorine residual, conductivity, and turbidity), ATI mono‐chloramine analyzer, the Hach Q45WQ Water Quality Panel (also for pH, free chlorine residual, conductivity, and turbidity), and the Intelletect Intellisonde™ (pH, free chlorine, mono chlorine, turbidity, conductivity, color, pressure, temperature, and flow).

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CONCENTRATE MANAGEMENT IN DESALINATION I

Select this Article		Concentrate Management and Disposal Practices in Australia James H. Jensen, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)550 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarises the concentrate management and disposal methods currently used and proposed in studies in Australia based on publically available information. Concentrate disposal considerations for desalination facilities in Australia include the potential environmental impacts and regulatory permitting requirements, including concentrate water quality, receiving water quality, stakeholder perception and issues, costs of the disposal system and other site specific issues. The operating 143,000 m³/day Perth seawater desalination facility and the coastal facilities under development use ocean outfalls with diffuser systems for mixing the concentrate with the receiving waters for disposal. However, the inland desalination plants have limited options for concentrate disposal. The disposal methods are often further limited by locally endangered and/or fragile habitat. The most common methods of concentrate disposal for inland facilities include surface water discharge, mixing with process or wastewater and concentration/evaporation. There may be other disposal methods that are unique to a particular facility and situation.

Select this Article		Desalination of Brackish Groundwater and Deep Well Injection of Concentrate in El Paso, Texas William R. Hutchison, Ph.D., P.E., P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)551 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract El Paso has relied on the Hueco Bolson as a major water supply source since 1903. As a result of high pumping, groundwater levels in the Hueco have declined and brackish groundwater has intruded into areas that historically yielded fresh groundwater. El Paso Water Utilities (EPWU) began reducing its Hueco pumping in 1989 as a result of a variety of water management initiatives. The reduction in pumping resulted in stabilized groundwater levels in many areas. However, brackish groundwater intrusion remains an issue. A 27.5 mgd desalination plant has recently been completed that will result in reductions in brackish groundwater intrusion, and allow EPWU to better utilize its fresh groundwater wells during droughts. The location of the pumping wells will provide an opportunity to intercept the brackish groundwater before it intrudes into historically fresh groundwater areas. This approach is a component of EPWU's overall groundwater management of the Hueco Bolson.

Select this Article		Membrane Treatment of Rio Grande Water for Municipal Water Production during the Non‐Irrigation Season Anthony J. Tarquin, Michael P. Fahy, and John E. Balliew ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)552 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Using impaired waters to meet increasing municipal demands has become nearly mandatory in many locations. This pilot scale project was undertaken to determine the feasibility of using brackish irrigation return flows (that also contain a small percentage of treated wastewater) to satisfy part of El Paso's municipal water demand during the non‐irrigation season. The first step was to determine if a sufficient quantity of water is available during the non‐irrigation season to provide 10 MGD of potable water. Historical data obtained from the United States Geological Survey for the years 1936 through 2004 revealed that a flow of at least 20 MGD is available 89% of the time. A simple microfiltration system (MF) was installed ahead of the reverse osmosis (RO) and nanofiltration (NF) membranes for suspended solids removal. The desalting results showed that both the RO and NF systems performed very well, with salt rejections in the 98% range. The lowest cost blended water was $0.76 per thousand gallons, produced in the NF unit when operating at 170 psi with a flux of 25 gallons per square foot per day. This cost includes disposal of concentrate through re‐blending with available irrigation return flows for possible irrigation of onions, the major winter crop in El Paso County, Texas.

Select this Article		Synopsis of National Research Council's Report on Desalination Sandeep Sethi, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)553 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The National Academies' National Research Council (NRC) formed a committee on desalination that was tasked with performing a critical analysis of the desalination technology, barriers to its widespread implementation, and the development of a national strategic research agenda. A synopsis of the final committee report including the major conclusions and recommendations are presented in this paper.

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CONCENTRATE MANAGEMENT IN DESALINATION 2

Select this Article		Cost Comparison of Membrane Treatment and Concentrate Management Practices at Drinking Water Treatment Plants in Florida Berrin Tansel and Irina Sosnikhina ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)554 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Design improvements, operational simplicity, advancements in new membrane materials, and competition in membrane industry have reduced both capital and operating costs of nano filtration (NF) and reverse osmosis (RO) systems for drinking water treatment applications. In Florida, the use of membrane technologies has increased to about 200 MGD today in comparison to 60 MGD in 1994. Currently, there are 125 membrane treatment systems in Florida with design capacities ranging from 800 gallons per day (gpd) to 25 MGD. A survey of economics of membrane treatment (NF and RO) facilities for drinking water treatment and concentrate management options were conducted for facilities located in Florida. Cost comparisons were based on data from different planning documents and plant surveys (Bergman, 1995; LEC, 2000; and budget data provided by the facilities). Since the capital costs depend on land cost, loan interests, consulting fees, design cost, pilot tests, costs of permits and other site specific factors; for accuracy of comparison, only the construction costs were considered for capital costs.

Select this Article		Desalination Concentrate: Bay vs. Ocean Patrick Treanor, P.E. and Val S. Frenkel, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)555 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sea and ocean Reverse Osmosis (RO) desalination plants are often designed to remove more than 90% of dissolved ingredients (organic and inorganic) from feed water, thus creating a permeate water that is potable. Typically 40–60% of the feed water is recovered as permeate water. The water not recovered as permeate becomes concentrated into a stream of RO concentrate (brine) because the salts rejected by RO remain in the unrecovered water. The RO concentrate is usually about 1.67 to 2.5 times the salt concentration of the source water, but can be as high as four times. RO concentrate discharged into a source water body is a major environmental consideration during the planning and design of bay or ocean desalination plants. Co‐location of desalination plants with wastewater treatment plants or power plants allows using a shared outfall to dilute the high salt concentration of RO concentrate. Diluting the RO concentrate in a shared effluent outfall mitigates the issue of high salinity around the outfall. This paper compares side by side two main classes of water bodies that receive concentrated brine discharge from Reverse Osmosis (RO) Desalination Plants: oceans (or open seas) and estuarine bays (under the influence of fresh water). These two classes of water bodies have inherent properties which drive not only the operation of RO plants, but also the physical and chemical reactions of outfall discharge. Major differences between oceans and estuarine bays are evident when comparing salinity levels, variability of salinity, and variability of the overall water quality. Furthermore, there are differences in terms of flora and fauna. Using a nuanced approach of comparing and contrasting oceans and estuarine bays as receiving waters for desalination plant concentrate, this paper brings to light the natural processes occurring offshore of potential desalination plant sites, and distinguishes what natural processes may be affected by brine entering the ecosystem.

Select this Article		Future Water Supply Desalination Technology: Forward Osmosis Co‐Located with Power Generation Tina Coop and Les Lampe, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)556 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Desalination — processes that remove excess salt and other minerals from water — is a critical technology in today's age of shrinking freshwater supplies. Currently Reverse Osmosis (RO) and thermal technologies, such as Multi‐Effect Distillation (MED) and Multi‐Stage Flash (MSF), dominate the desalination market. However, rising energy costs and government regulations on carbon emissions are likely to change the future of desalinating water. Seeking to identify and validate market attractiveness of emerging technologies to power and treat non‐freshwater sources, the authors evaluated whether the cutting‐edge membrane technology known as Forward Osmosis (FO) was a viable desalination method. Forward Osmosis (FO) uses highly concentrated carbon dioxide (CO₂) and ammonia (NH₃) to separate the freshwater from the brine. A thermal process is used to remove the CO₂ and NH₃ from the freshwater; the CO₂ and NH₃ are then recycled to be used again. The study concluded that even with its increased efficiency, FO alone will not resolve all of the world's desalination challenges. The study concluded that with its increased efficiency, FO can be successful under the proper circumstances.

Select this Article		New Strategies for Managing Desalination Concentrate with Zero Liquid Discharge from Two WRF Research Projects Rick Bond and Srinivas Veerapaneni ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)557 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The need for affordable inland desalination in the U.S. is urgent. Many utilities are struggling to meet growing water demands and manage increasing salinity levels in their fresh water sources. The greatest challenge faced by utilities wishing to desalinate inland water sources is concentrate management. Discharge of concentrate to surface waters or deep well injection raise environmental concerns and these alternatives are increasingly difficult to permit. Discharge to a wastewater treatment plant simply recycles salinity or passes it on to a downstream user. The alternative is zero liquid discharge (ZLD) treatment. In ZLD, concentrate is treated so that the water is recovered for beneficial use and there is no discharge of liquid waste from treatment. Desalination with zero liquid discharge is the subject of two recent AwwaRF research projects. The technical approach in both projects involves treating RO concentrate to reduce its membrane fouling potential prior to a second desalination step. The report for the first project, Zero Liquid Discharge for Inland Desalination, was published in 2007. The research involved computer modeling, bench‐scale testing and pilot‐scale testing. The research results were used to estimate cost and energy requirements for the proposed approach and compare them to those for the established ZLD approach using thermal desalination and evaporation ponds. It was estimated that treatment costs and energy consumption could be reduced by 50 to 70 percent with the proposed treatment approach.

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WATER. WASTEWATER, AND STORMWATER TOPICS

Select this Article		A Mobile Emergency Drinking Water System Powered by Renewable Energy Matthew Vitello, Andrew Curtis Elmore, and Mariesa Crow ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)558 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract To increase the mobility and wellbeing of U.S. Army units a relatively light‐weight, portable source of clean drinking water is needed to replace current practices of obtaining potable water. In addition to the need expressed by the Army, it has become apparent that delivering a reliable source of clean drinking water to municipalities during the aftermath of natural disasters such as Hurricane's Katrina and Ike is essential. Water supply and the associated transportation of potable water is a considerable burden on recovery efforts following a natural disaster. A low cost trailer mounted system, which uses an ultraviolet (UV) disinfection unit in conjunction with cartridge filters, can provide potable water from local surface water bodies until the infrastructure is renewed. The system is powered by a hybrid photovoltaic array and wind turbine system, which allows for the capability to pump and treat surface water when grid power is unavailable. In an effort to maintain low maintenance and increased storability associated with the system, relatively high‐maintenance lead acid batteries have been eliminated, which also helps to reduce the system weight. Tests have been conducted to assess the ease of use, effectiveness and feasibility of the system.

Select this Article		Adding Value to Sanitary Sewers — An Important Asset of Municipalities V. Firat Sever and Barton Bradshaw ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)559 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Sanitary sewer rehabilitation programs are generally triggered by the need for reducing infiltration and inflow and restoring structural integrity of a collection system. On the other hand, improving the condition of the components (essentially pipes and manholes) of a wastewater collection system may turn sanitary sewer rehabilitation into a financially beneficial practice in addition to maintaining desired level of service and regulatory compliance. This study discusses a sanitary sewer rehabilitation program being applied on Marco Island, Florida as a case study of proactive wastewater collection system management. The existing system was evaluated using closed‐circuit‐TV inspection of pipelines and visual inspection of manholes. Accordingly, a rehabilitation program was developed which is based on using trenchless technologies to maximum extent. Depreciation of the system was analyzed for the next 70 years without rehabilitation to estimate the rate of return of rehabilitation. The results indicated the rehabilitation cost is approximately 16 percent of the depreciation that would occur in 70 years in today's dollars.

Select this Article		Ecosystem Services Approach to Public Facility Planning A. Yap, G. Honan, and M. Kealy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)560 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract For the City of Damascus, Oregon incorporated in 2004, achieving sustainability includes balancing the preservation of natural capital and ecological services with provision of public facilities and services to support new development. This rural, forested and agricultural rich City is set among volcanic buttes and a network of perennial and ephemeral streams and riparian corridors tributary to the Clackamas River. Current residents value the diversity of the natural landscape for its scenic beauty as well as for its contributions to biodiversity, clean water, clean air, and the rural character of the area, as well as for the opportunities for income from use of their lands from timber sales and agricultural endeavors. These agricultural endeavors range from organic vegetable farms to Christmas tree lots. Inclusion of this area into the Urban Growth Boundary (UGB) in 2002 dramatically changed the land use regulations that had previously protected the forest and agricultural uses and opened the door to more intensive residential and commercial development. The focus of this paper is on the conceptual approach to identifying, assessing, and valuing ecosystem services; and on the development of approaches for managing natural capital to provide valued ecological services.

Select this Article		An Evaluation of Graywater Reuse Utilizing a Constructed Wetland Treatment System A. W. Jokerst, L. A. Roesner, and S. E. Sharvelle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)561 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Increasing demand for conservation of water resources has prompted the notion that the separation of graywater (all wastewater not including toilet and kitchen sources) from sewer effluents through the use of dual‐plumbed systems may enable graywater to be reused. Constructed wetland systems for conditioning combined wastewater effluents are widely used, and offer an efficient solution for onsite wastewater treatment of a variety of pollutants. However, limited long‐term research has been conducted to determine the effectiveness of such systems specifically on graywater. This paper aims to determine the viability and efficiency of constructed wetlands for graywater treatment, and assess the water quality produced from such systems. The experimental method involves monitoring of specific water quality constituents under varying operating conditions in a prototype constructed graywater wetland. Preliminary findings show the wetland significantly reduces many graywater contaminants including pathogens, biochemical oxygen demands, solids, and nitrogen and phosphorus species.

Select this Article		Application of Enhanced Methods of Phosphorus and Nitrogen Removal from Wastewater Mohammad Reza Fallahpour, Mojtaba Fazeli, and Seyed Ahmad Mirbagheri ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)562 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Compounds of nitrogen and phosphor in wastewater treatment plant effluents have caused serious and even dangerous problems including incidence of methemoglobinemia in new born babies as a result of consumption of water contaminated with nitrate and also nitrification in surface water. Various processes and methods at different scales have been used with the aim to remove effectively such compounds so as to prevent the potential of harmful and dangerous incidences mentioned above at its lowest level. One of these processes is the use of A²/O (Anaerobic, Anoxic, Oxic) in activated sludge process. The purpose of this process undertaken in a pilot system is removal of carbon and phosphor over 90 percent and also reduction of nitrogen density in effluent in MLSS.

Select this Article		Bench‐Scale Ozonation of Raw Industrial and Municipal Wastewater Richard O. Mines, Jr., Cary M. Oglesby, and Laura W. Lackey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)563 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This project involved the design, operation, and testing of a bench‐scale ozonation wastewater treatment system. Untreated municipal and industrial wastewater was collected from the influent chamber to the Rocky Creek Wastewater Treatment Plant (WWTP) in Macon, Georgia. The industrial wastewater consisted of paper mill effluent from the Graphic Packaging Plant adjacent to the Rocky Creek WWTP. The Rocky Creek WWTP treats wastewater in an extended aeration activated sludge process. To accomplish this research, a 10‐liter clear PVC, semi‐batch, bubble column was used to disperse ozone bubbles through a porous diffuser near the bottom of the column. Three 24‐hour runs were conducted on each type of wastewater. The ozone was administered at loading rates of 0.60, 4.70, and 9.92 mg O₃/min, respectively, to 6 liters of either raw municipal or industrial wastewater. The following parameters were measured frequently during each 24‐hour run: pH, chemical oxygen demand (COD), ammonia, nitrite, nitrate, phosphorus, conductivity, turbidity, total suspended solids (TSS), volatile suspended solids (VSS), total dissolved solids (TDS), and total volatile solids (TVS). Overall COD removal for the municipal and industrial wastewater averaged 82% and 84%, respectively, whereas, overall TSS removal averaged 83% and 81%, respectively. The ozonation degradation rate constant (K_D) based on TSS destruction ranged from 0.054 hr⁻¹ to 0.072 hr⁻¹ for the municipal wastewater and from 0.017 hr⁻¹ to 0.066 hr⁻¹ for the industrial wastewater.

Select this Article		Biological Nutrient Removal from On‐Site Wastewater Treatment Systems Using a Membrane Aerated Bioreactor Zhihua Liang and Zhiqiang Hu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)564 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This study aimed to develop a low cost bioreactor process to efficiently remove organic compounds and nutrients from on‐site wastewater treatment systems. A laboratory‐scale anaerobic membrane‐aerated biofilm bioreactor (ANMABR) using a gas‐permeable silicone tubing covered with non‐woven fabrics was constructed to evaluate the efficiency of chemical oxygen demand (COD) and nitrogen removal in the system. After 250 days of continuous reactor operation, the experiment results showed consistent COD and NH₄–N removal efficiencies at 89±6 and 82±5%, respectively. The total nitrogen (TN) removal efficiency was 64±8% with an effluent average total nitrogen concentration of 11 mg/L. From day 89 to day 120 the biofilm reactor experienced a shock load running with C/N ratio of 2:1 with influent NH₄–N increased to 150 mg/L. The COD removal efficiency was not affected after the shock load, but NH₄–N and TN removal efficiencies were decreased down to 44 and 22%, respectively. This study demonstrated that gas‐permeable tubing/membrane could be used to treat wastewater containing low organic and nitrogen loadings from on‐site wastewater treatment systems. Improvement is still needed under the shock loading conditions for on‐site wastewater treatment systems.

Select this Article		Boundary Conditions for Simulating Complex Storm‐Sewer Systems in Free Surface, Pressurized and Mixed Flow Conditions Arturo S. León, Xiaofeng Liu, Mohamed S. Ghidaoui, Arthur R. Schmidt, and Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)565 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes part of the work presented in León et al. (2009), which presents integrated boundary conditions (BCs) for simulating free surface, pressurized, and the simultaneous occurrence of free surface and pressurized flows (mixed flows) when the free surface region is modeled using the 1D Saint‐Venant equations and the pressurized region is modeled using the 1D compressible waterhammer equations. The present paper describes the results of the application of the integrated boundary conditions for modeling free surface, pressurized, and mixed transient flow conditions in two test cases. The first test case is a hypothetical test and the second is an experimental work in an oscillation tube performed by the authors of this paper. Computational Fluid Dynamics (CFD) modeling results were used as frame of comparison for the first test case and experimental results besides CFD results were used for the second one. The results show that the integrated boundary conditions can be used with good accuracy for simulating complex storm‐sewer systems in free surface, pressurized and mixed flow conditions. The integrated boundary conditions are general and they can be used to simulate point and storage junctions with any number of inflowing and outflowing pipes. The integrated boundary conditions were implemented in the Illinois Transient Model (ITM), which has been used to study hydraulic transients in the Calumet system of the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC). The results of the latter study are not presented in this paper.

Select this Article		City of St. Louis Permeable Pavement Alley Pilot Study Dave Yates, P.E. Author and Marjorie Melton, P.E. C.O. Author ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)566 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of St. Louis Board of Public Service (BPS) formed a partnership with the Missouri Department of Conservation (MDC), CH2M Hill, the Metropolitan St. Louis Sewer District (MSD), Southern Illinois University — Edwardsville (SIUE), and East‐West Gateway Council of Governments (EWG) in mid‐2007 to find ways to incorporate low impact development (LID) techniques into City of St. Louis projects. The team identified pervious paving as the first best management practice (BMP) to investigate due to the multiple benefits it provides and the ample opportunity to utilize the practice in City‐owned projects. This project is one of many initiatives in the City of St. Louis Climate Change Plan. Impervious surfaces, such as roads, rooftops and sidewalks within the City of St. Louis contribute to water quality and quantity problems as well as the urban heat island. Converting impervious surfaces to pervious paving, an Environmental Protection Agency (EPA) recognized best management practice (BMP), reduces stormwater runoff, captures peak flows, replenishes water tables and aquifers, minimizes flash flooding and standing water, prevents warm and polluted water from entering the streams, mitigates surface pollutants and reduces heat island effect. Pilot study data will be used to support a change in City of St. Louis policy to potentially require pervious paving in its alleys city wide. The data will also be used to promote change in private developments and other City paving projects where appropriate. The results will be used by MSD to determine if permeable pavements can be used as BMP either in junction with other BMPs or as a stand‐alone BMP.

Select this Article		Competing Risks and the Development of Adaptive Management Plans for Water Resources: Field Reconnaissance Investigation of Risks to Fishes and Other Aquatic Biota Exposed to Endocrine Disrupting Chemicals (EDCs) in Lake Mead, Nevada USA Greg Linder and Edward E. Little ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)567 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The analysis and characterization of competing risks for water resources rely on a wide spectrum of tools to evaluate hazards and risks associated with their management. For example, waters of the lower Colorado River stored in reservoirs such as Lake Mead present a wide range of competing risks related to water quantity and water quality. These risks are often interdependent and complicated by competing uses of source waters for sustaining biological resources and for supporting a range of agricultural, municipal, recreational, and industrial uses. USGS is currently conducting a series of interdisciplinary case‐studies on water quality of Lake Mead and its source waters. In this case‐study we examine selected constituents potentially entering the Lake Mead system, particularly endocrine disrupting chemicals (EDCs). Worldwide, a number of environmental EDCs have been identified that affect reproduction, development, and adaptive behaviors in a wide range of organisms. Many EDCs are minimally affected by current treatment technologies and occur in treated sewage effluents. Several EDCs have been detected in Lake Mead, and several substances have been identified that are of concern because of potential impacts to the aquatic biota, including the sport fishery of Lake Mead and endangered razorback suckers (Xyrauchen texanus) that occur in the Colorado River system. For example, altered biomarkers relevant to reproduction and thyroid function in fishes have been observed and may be predictive of impaired metabolism and development. Few studies, however, have addressed whether such EDC‐induced responses observed in the field have an ecologically significant effect on the reproductive success of fishes. To identify potential linkages between EDCs and species of management concern, the risk analysis and characterization in this reconnaissance study focused on effects (and attendant uncertainties) that might be expressed by exposed populations. In addition, risk reduction measures that may be of interest to resource managers are considered relative to emerging contaminants in treated effluents, interdependencies among biological resources at risk, and uses of reservoir waters derived from multiple inflows of widely varying qualities.

Select this Article		Construction of a Low‐Flow Channel in Barber Creek: Case Study in the Powder River Basin, Wyoming Robert W. Thoman, P.E. and J. J. Brown ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)568 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Design and construction of low‐flow channels to convey coalbed natural gas‐produced (CBNG‐produced) waters to higher‐order streams is a relatively new water management option being employed in the Powder River Basin (PRB) of northeast Wyoming. In this case study, a low‐flow channel was designed, constructed, and maintained on Barber Creek and South Prong Barber Creek in the PRB near Gillette, Wyoming. Engineering design challenges include large ephemeral flows, steep slopes, and cohesive soils. Initial design was based on aerial photography analysis, low‐level reconnaissance flights, and field exploration. Existing channels were surveyed to establish representative channel sinuosity, depth, slope, and stability of streams in close proximity to the study area. The final design includes approximately 1,370 m (4,500 ft) of channel reconstruction on South Prong Barber Creek and 1,800 m (5,900 ft) of channel reconstruction on Barber Creek. Clay soils hardened by severe drought conditions presented an unexpected challenge during construction, as did several significant rainfall events which occurred immediately following initial construction, damaging design elements already in place. Automatic streamflow gages located upstream and downstream of the study area recorded the subsequent flood events. Post construction design considerations include stabilization of the existing channel and installation of erosion mitigation measures. This study provides a full range of design criteria, construction procedures, and mitigation efforts for consideration in the design of stable low‐flow conveyance channels for CBNG‐produced waters.

Select this Article		Decentralized Anaerobic Treatment of Blackwater: A Sustainable Development Technology Concept for Urban Water Management N. T. Gallagher and S. Sharvelle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)569 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract As populations continue to increase, the demand for limited water resources has increased. Sustainable water technologies and management methods are critical to our meeting future water quantity and quality demands. Decentralized treatment of blackwater under anaerobic conditions is a wastewater treatment technology being explored for application in new developments. Decentralized anaerobic treatment of blackwater stands out in its ability to conserve available green water and energy resources and promote reuse of these resources at a local level. A pilot scale anaerobic reactor is under construction at the Colorado State University Foothills Campus to treat blackwater (toilet and kitchen sink wastewater) from a building occupied by laboratory and office space. This project is a demonstration study on the economic and technical feasibility of using anaerobic digestion for treatment of blackwater. Eventually, it is anticipated that biogas produced in digesters will be used as a green energy alternative to current energy sources and treated effluent water will be evaluated for reuse onsite for irrigation or other non‐potable uses. Treatment efficiencies of the anaerobic process under varying loading and environmental conditions will be monitored in addition to methane production. A decision analysis tool for cluster decentralized wastewater treatment (DWWT) will be developed to assist decision making entities in determining the applicability of DWWT.

Select this Article		Development of a National GIS Database for Municipal Water and Wastewater Pipe Infrastructure System Sunil Sinha, Randy Dymond, Rahul Vemulapally, Thomas Dickerson, and Seth Perry ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)570 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The problems posed by aging infrastructure are receiving increased attention in the United States, thanks to critical reports by the American Society of Civil Engineers, and in some cases, due to public outcry in the wake of infrastructure failures. The U.S. Environmental Protection Agency (EPA) has a special interest in the operations and management of public drinking water and sanitary sewer systems. Infrastructure utilities are facing increasing pressure to implement advanced asset management plans in order to improve the efficiency with which their systems are operated and maintained. As a result, most utility operators are actively working to develop GIS mapping and databases of their pipe networks. However, there is no standard data model for water or sewer systems, thus each utility has developed its own method for storing data; this has created complex problems associated with multi‐jurisdictional planning activities, research, and oversight.

Select this Article		Engineering Natural Filtration Systems to Remove Selenium, Nitrate, and Bacteria from Impaired Surface Waters — Foundational Studies Ken Susilo, P.E., CPSWQ, Eric Strecker, P.E., and Randy Sundberg, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)571 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Selenium is among the pollutants of concern in a growing number of areas within California. TMDLs proposed by USEPA (USEPA, 2002) for the San Diego Creek watershed in Orange County, California (and in Ballona Creek and Los Angeles River in Los Angeles County) calls for an in‐stream standard of 5 ppb total selenium. Selenium sources and treatment methods, however, are significantly different than those typically utilized as stormwater BMPs for metals such as copper, lead and zinc. Studies on the sources of selenium in the San Diego Creek Watershed indicated that a major potential source is groundwater seepage, particularly in areas where the groundwater table is shallow. Thus dry‐weather concentrations and loads are of the most interest. Within the San Diego Creek Watershed, flows appear to correspond to a location where historically, naturally occurring selenium became sequestered under anaerobic conditions in the peat soils within a swamp. Urbanization and draining of the swamp appears to have created aerobic conditions, releasing selenium from these sediments into groundwater in a soluble phase. Selenium concentrations in the surface water discharge have been observed in the 50 ppb range, and local groundwater selenium concentrations commonly exceed 100 ppb.

Select this Article		Extension of an LA‐QUAL Model for Evaluating a Proposed Wastewater Discharge to Realistic Receiving Water Temperature and Flow Conditions Chris Herrington, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)572 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Multiple steady‐state LA‐QUAL(version 8.0) models for varying temperature and flow conditions were evaluated and used to generate a time‐series prediction of water quality impacts from a proposed wastewater discharge to Bear Creek (Hays County, Texas) at the upstream boundary of the Barton Springs portion of the Edwards Aquifer Recharge Zone. LA‐QUAL predicted output is sensitive to dilution (amount of natural creek flow present) and temperature (removal rates are temperature‐dependent) (Herrington 2008). Although LA‐QUAL (or QUAL‐TX) models are commonly used by Texas Commission on Environmental Quality staff to evaluate potential dissolved oxygen degradation for new discharges (TCEQ 2003), typically only a single critical condition (low flow, high temperature) is considered. The use of multiple models is a more accurate representation of the temporal variability in flow and temperature. Using this approach, the proposed discharge is predicted to degrade the water quality of Bear Creek and the Edwards Aquifer. However, this analysis is still only a conservative approximation of the actual degradation potential and does not simulate more dynamic ecological responses such as nutrient spiraling or storm event driven sediment re‐suspension.

Select this Article		Gray Water and Treated Effluent Reuse Steven Roznowski, Kristofer Bruun, and Larry Roesner, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)573 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Graywater and treated effluent reuse is a concept that has been gaining favor in recent years. For reuse to be implemented, issues with water usage rights, health risks, and environmental impacts will need to be resolved. Even with the resolution of these issues, graywater reuse will not become prevalent until it has been shown to be cost effective. Cities looking to implement a city‐wide or community graywater or treated effluent reuse system would be particularly interested in knowing the cost savings created by water reuse. The reuse of graywater and treated effluent impacts demand for potable water supply as well as the loads placed on wastewater treatment facilities, therefore a fully integrated urban water system must be considered in any cost analysis. This report outlines a computer program developed to grapple with the problems of creating a fully‐integrated urban water model. This program is capable of calculating the cost of a wide array of scenarios ranging from no urban water reuse to complete reuse of graywater and/or wastewater effluent. It considers factors such as rainfall volumes, population data, residential water demand, industrial water demand, and of course water supply and redistribution costs. Furthermore, the program can perform analyses on a seasonal or annual basis to account for varying residential irrigation demands. Average household lawn area and lawn irrigation requirements can be changed and calculations are automatically updated based on mean temperature and rainfall frequency.

Select this Article		Green Alternatives to Channel Stabilization Richard E. Besancon, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)574 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of the project was to improve water quality, repair and stabilize eroding banks, and add wetlands to the project site. As mitigation for channel and wetland disturbance on a commercial and residential development in eastern Illinois, Burns & McDonnell performed channel restoration/stabilization using a combination of traditional and green techniques to repair severely eroded bank and construct additional wetlands adjacent to the creek. Canteen Creek is a highly eroded and degraded due to uncontrolled stormwater discharges into the creek upstream of the site. The existing stream has degraded and left vertical banks in many locations.

Select this Article		Hydraulic Modeling and Engineering Evaluation of Fort Myers Beach's Water Distribution System Jinsheng Huo, Ph.D., P.E., BCEE, Robert Garland, P.E., Doug Eckmann, P.E., BCEE, Jack Green, and Cathie Lewis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)575 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract This paper applies hydraulic modeling to evaluate the water distribution system of the Town of Fort Myers Beach, Florida. Fort Myers Beach is a small island town located in Southwest Florida. The Town does not have its own water treatment plant. Instead, the finished water is provided by Lee County. To meet fire protection and other emergency uses, the Town has two ground storages and three booster pumping stations to provide adequate water flow and residual pressure. Like other coastal communities in Florida, the number of residence and water demand patterns in the Town vary significantly by two seasons (wet and dry). Therefore, it is a challenging task to design and evaluate a water supply system to meet two dramatically different demand characteristics. In this paper, engineers evaluate flow and pressure in the water distribution system under both PDD + FF (Peak Day Demand + Fire Flow) and PHD (Peak Hour Demand) scenarios, and the existing storage and pumping capacities as compared to the national standards and local ordinances. Based on the simulation results, critical areas with potential low pressures, especially when fire flow is needed, are identified and recommendations of system upgrading are also provided. The feasibility study of building the Town's own water treatment plant is also recommended due to increasing water demand at the south end of the island and raising water fees per the annual and monthly water bill reports. Furthermore, the additional ground storage tank capacity is suggested to meet fire protections and other emergencies (for example, hurricane events).

Select this Article		Innovative Strategies Alleviate Water Stress in South East Queensland, Australia Hua Jiang, Scott Freeman, and Jonathan Bates ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)576 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Brisbane, located in South East Queensland, Australia, is one of the fastest growing major metropolitan areas in Australia and Queensland's state capital. In the past seven years, rapid population growth and unprecedented drought has placed tremendous pressure on Brisbane's drinking water supply. As a result, in July 2007, the combined dam levels fell to a historical low of 17 percent, or less than 16 months supply. Recycled water is one of several strategies that the Queensland Government has adopted as part of its efforts to secure the region's drinking water supplies and to support sustainable economic growth. The Bundamba Advanced Water Treatment Plant (BAWTP) is part of the AU$2.5 billion Western Corridor Recycled Water Project that will produce up to 232 megaliters of purified recycled water each day for use in power stations, industry, agriculture and, should the regional water storages fall below 40 percent, to supplement the Wivenhoe Dam.

Select this Article		Multi‐Objective Design of Transient Network Models Bong Seog Jung, Misgana Muleta, and Paul F. Boulos ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)577 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The optimal design of a water distribution system under transient conditions is formulated as a two‐objective optimization problem. The objectives are minimization of the total pipe costs and maximization of the hydraulic reliability for the transient network design model. Unlike most optimization models in which demands are set to their end‐of‐life levels, this approach assumes that the demand loadings vary throughout the design life of the system. Evolutionary algorithms are applied to support efficient search for Pareto optimal solutions to the dual‐objective optimization problem. An example application is presented and relevant conclusions are stated.

Select this Article		Municipal Water Systems in the Columbia River Basin: A Portfolio Management Approach for Multiple Benefits Mark A. Anderson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)578 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The City of Gresham, Oregon has a population of 100,000 people. On the eastern edge of the Portland metropolitan area, Gresham is located on the south shore of the Columbia River. Gresham's water supply is anticipated to be adequate until at least 2050 from surface and groundwater sources. Wastewater is collected for secondary treatment. Treated effluent is discharged directly to the Columbia River. This reach of the Columbia River is designated as a temperature‐limited stream under Section 303(d) of the Clean Water Act. A number of other potential nutrient and pollutant limits may affect permitted effluent discharge in the future. A draft Total Maximum Daily Load (TMDL) for temperature assigns a heat load allocation to Gresham that is projected to be exceeded by as early as 2020.

Select this Article		Reliability Based Design of Water Distribution Network (WDN) Considering the Reliability of Nodal Pressures N. Ghajarnia, O. Bozorg Haddad, and M. A. Mariño ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)579 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Optimization of water distribution networks (WDN) has been one of the main challenges of researchers for many years. By paying one‐dimensional attention to the minimization of WDN costs, one would ignore efficiency factors such as the reliability in delivering nodal demands with desired pressure. By considering the nodal pressure satisfaction as a rigid constraint, the maximum reliability will occur not reflecting the influence of a minor reliability reduction in the system cost. Hence, there is a need for designers and decision makers to have a landscape of the system performance, considering the flexible permissible nodal pressure and its effect on the system cost. In this paper, honey‐bee mating optimization (HBMO) is applied in a benchmark WDN (two‐loop) problem. The objective is minimization of cost with respect to different levels of reliability in the system during the operational period. Because in WDNs the decision variables are in a discrete domain, a minor decrease in the reliability of nodal pressure can yield a major cost reduction. Furthermore, by, considering different nodal pressure reliabilities, critical nodes of the network can be determined.

Select this Article		Removal of Selenium and Nitrate from Surface Waters Using a Subsurface Microbial Filter Stephen Lyon, Scott Lynch, Imad Feghali, and Randy Sundberg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)580 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Many surface waters throughout the United States exceed one or more common forms of regulated contaminants. This study describes a pilot&hyphen;scale facility that was designed to remove nitrate and selenium (selenate) from surface waters by microbial processes. In an oxygen‐free environment, nitrate is reduced to nitrogen gas and selenate is reduced to an insoluble salt that precipitates onto the biofilm. Based on the results from bench‐scale tests, a demonstration facility was designed and constructed adjacent to a creek in Irvine, CA. This paper describes the design, construction and lessons learned in the development of a gravel&hyphen;filled filter whose effluent will meet the current standards for nitrate and selenium in surface waters. The facility treated in approximately 194,000 gallons per day and was designed to run in a contaminant removal, recycling and back‐flush mode. The benefits of this system are the consistent removal of nitrate and selenium throughout the year with a low O&M cost and the possibility of multiple uses of the land that could include both the belowhyphen;grade filter and a parking lot or recreational area at the surface. This project is an example of a local water district assuming the role of environmental steward whose projects provides multiple benefits to the community and wildlife within the watershed.

Select this Article		Research and Application of Activated Sludge Models Jinsheng Huo, Ph.D., P.E., BCEE, Min Ji, and Yan Jiang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)581 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract With the growing demands on better effluent quality and higher cost‐effectiveness wastewater treatment systems, the traditional methods to design and manage the Wastewater Treatment Plant (WWTP) by experiences and current standards could not meet rapidly developing wastewater industry. As a result, it is an inevitable trend to develop mathematical models and corresponding simulating software for wastewater treatment processes to improve the performance and cost‐effectiveness of critical environmental protections. Based on International Water Association (IWA)'s activated sludge models (ASMs), an Activated Sludge Process Simulator — Carbon Oxidation (ASPS‐CO) program is developed to simulate and optimize the design, operation, and management of WWTPs. With the focus on the carbon oxidation only, the ASPS‐CO program models three typical biological processes: aerobic growth of heterotrophs, death and lysis of heterotrophs, and “hydrolysis” of particulate organics. This ASPS‐CO program also develops its own sub‐modules to calibrate model parameters, convert traditional measured data, and replace commonly missing data, etc. Therefore, it can simulate not only the water quality of influent and effluent in WWTPs, but also the operating conditions of series continuous stirred‐tank reactors (CSTRs): for example, concentration and composition of biomass, and quality and composition of the wastewater, etc. The simulations of the Tianjin Ji‐zhuang‐zi WWTP using the ASPS‐CO program indicate that the results closely match the measured data, which proves to be a reliable method to simulation other WWTPs. In conclusion, this method can provide a reliable theoretical foundation for engineers and researchers to design, operation, and management of wastewater treatment processes. Furthermore, it provides confidences in decision‐makers to use this method as an important reference to make critical decisions.

Select this Article		Risk Assessment to the Environment Due to Anionic Surfactants in Treated Sewages and Dried Sludges Arvind Kumar Mungray and Pradeep Kumar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)582 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Paper presents the outcome of a 21 month monitoring study on the anionic surfactants (AS) at the 70 ML/d UASB-PP (up-flow anaerobic sludge blanket - polishing ponds) based sewage treatment plant (STP). The average removal of AS was only around 30%. Appreciable concentration of AS was being discharged to the watercourse (average 3.60 mg/L; range 1.69–4.94 mg/L). Compare to this >92% removal was found in an 18 ML/d activated sludge process (ASP) based STP with an average 0.13 mg/L of AS is discharged to the surface waters. AS concentrations averaged 5909 and 810 mg/kg dry wt. in wet UASB and dried sludges respectively. Treated sewage from UASB-PP based STP when discharged to aquatic ecosystems are likely to generate substantial risk. Post-treatment using 1 day detention, anaerobic, non-algal polishing ponds was found ineffective. Need of utilizing an aerobic method of post-treatment of UASB effluent in place of an anaerobic one has been emphasized. Natural drying of UASB sludge on sludge drying beds (SDBs) under aerobic conditions results in reduction of adsorbed AS by around 86%. Application of UASB sludges on SDBs was found simple, economical and effective. While disposal of treated UASB-PP effluent may cause risk to aquatic ecosystems, use of dried UASB sludges is not likely to cause risk to terrestrial ecosystems.

Select this Article		Riverbank Filtration for Water Supply: Indian Experience Pradeep Kumar and Indu Mehrotra ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)583 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The efficiency of three RBF systems has been presented. At Haridwar dug wells are water abstraction devices and the source water is the River Ganga which is relatively less polluted. In non‐monsoon months, RBF reduced turbidity and coliform by 1 and 3 logs respectively. Removal in monsoon increased to more than 2 and 4 logs for turbidity and coliform respectively. Vertical tube‐wells in the vicinity of the Lake Nainital pump lakebank‐filtrate at Nainital. The well water when compared with lake water showed 5.2 log removal of total coliform, 4.2 log removal of fecal coliform, 1.4 log removal of turbidity and 1.6 log removal of COD. At Mathura, water is collected by a radial collector well placed in the bed of the River Yamuna, a polluted river. Reduction in DOC and UV absorbance was 0.3 log. Colour decreased by 0.4 log. Total and fecal coliform removals were 2.6 and 1.3 logs respectively.

Select this Article		Sustainable Design and Construction of Earthen‐Dam Reservoirs for Water Produced in Association with Coalbed Natural Gas in the Powder River Basin, Wyoming J. J. Brown and Robert W. Thoman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)584 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Surface impoundment of produced water from coalbed natural gas (CBNG) development is a water management option routinely employed by operators in Wyoming's Powder River Basin (PRB). A substantial increase in CBNG development in recent years has resulted in the need for documented guidance and standards regarding the sustainable design and construction of impoundment structures; specifically earthen‐dam reservoirs. Earthen‐dam reservoirs are a cost effective, relatively low‐impact management alternative for produced water, which also allows for a variety of secondary water management options such as evaporation, infiltration, local aquifer recharge, irrigation, and livestock and wildlife watering. Earthen dams are also high‐risk structures with the potential for extensive property damage and possible threat to public safety upon failure. A guidance document is beneficial to all stakeholders, from regulators and local governments to land and resource management agencies, ranchers, and landowners. Design elements and construction procedures presented in the guidance document are based on data collected during the design and construction of nearly 1,000 large reservoirs and more than 4,000 smaller stock reservoirs in the PRB over the past eight years. Soil conditions, subsurface and surface hydrology, topography, and geology specific to the PRB are considered, as are the regulatory requirements of the Wyoming State Engineer's Office and the Wyoming Oil and Gas Conservation Commission. While design considerations vary depending on intended beneficial use, landowner requirements, and pertinent regulations, sustainability and minimal disturbance are the governing objectives in all circumstances. Remediation and mitigation procedures for potential short and long‐term concerns such as differential settlement, piping, excess surface erosion, and seepage are derived from field trial observations. Design aspects specific to on‐ and off‐channel impoundments, planned long term use, and reclamation following short term use are provided.

Select this Article		Sustainable Development of Agriculture: Urban Waste Water a Viable Mean for Irrigation Chhedi Lal and Vaibhav Gupta ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)585 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract World Commission on Environment and Development in “Our Common Future” (Brundtland, 1987) defines the sustainable development as “a strategy that meets the needs of the present without compromising the ability of future generation to achieve their own requirements”. Developing countries have to face double challenge for sustainable agriculture, firstly to increase food production and secondly to maintain if not to improve resource and environmental quality. EI Bassam (1998) reported that per capita land required for food, oxygen and water security are 15–20 m², 6–10 m² and 3–6 m², respectively under controlled conditions. This could be achieved if innovative technical means and efficient material recycling systems are implemented. One of the biggest problems that agriculture will face in the years to come will be of availability of good quality water for irrigation purpose. The water available and the ultimate irrigation potential do not level up. Under ground water contributes to more than 70% of the total ultimate potential through minor irrigation. To cater to the depletion of good quality water alternate sources are being looked into.

Select this Article		Treatment Performance of Wastewater Lagoons in South Yungas Province of Bolivia Helen E. Muga, James R. Mihelcic, Nathan W. Reents, Santiago Morales, Gabriela Gemio, Meredith Ballard, Valerie J. Fuchs, Cara M. Hanson, Esther M. Johnson, and Alison M. Hoyt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)586 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract The operation of wastewater lagoons systems located in the South Yungas Province of Bolivia has been analyzed over a 2‐year period. Facultative and maturation lagoons were evaluated for their performance in removing total suspended solids (TSS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), nitrogen, phosphorus, and coliforms. Facultative lagoons operating in San Antonio were found to remove approximately 74% total suspended solids, 70–89% BOD, 62–85% COD, 53% nitrogen, 52% phosphorus and 97.8–99.9% coliforms. Maturation ponds were found to remove 74–93% total suspended solids, 22–62% BOD, 10–95% COD, 3% nitrogen, 20–95% phosphorus and 77.4–99.96% coliforms. Results from the 2‐year study indicate that these wastewater treatment systems are currently performing as expected; however regular maintenance, specifically removing algae every (2 weeks) is required. The removal percentages of the treatment systems (comparing influent to effluent) ranged from 74–97% TSS, 78–98% BOD, 70–99.7% COD, 58–77% nitrogen, 62–99.9% phosphorus, and 99.99% coliforms.

Select this Article		Understanding and Controlling Fouling in Membrane Bioreactors Roger Babcock, Jr. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)587 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Membrane bioreactors (MBRs) are an activated sludge process in which the conventional secondary clarifier is replaced by a membrane separation process (either microfiltration or ultrafiltration). As with other membrane systems, the most important characteristics are the membrane flux and the membrane permeability both of which are highly dependent upon temperature and degree of fouling. Like other membrane systems but to a greater degree, MBRs are susceptible to biofouling. Biofouling is not well understood but does increase operating pressure, reduce maximum flux, increase recovery cleaning requirements, and possibly reduce total membrane life. All of these effects of biofouling have adverse effects on either initial capital cost or ongoing operation and maintenance costs for MBRs. The overall goal of this research is to obtain a better understanding of biofouling in MBRs and methods to control said fouling in order to improve the economics of water recycling. The conclusions thus far from the pilot and bench‐scale studies are that SMP and EPS are very important relative to biofouling in MBRs and that several tools are useful to examine biofouling trends. These tools include the critical flux test, resistance in series component analysis, and measurement of different fractions of EPS and SMP.

Select this Article		Using Media Filters in a Distributed Wastewater System Serving an Ecotourism‐Oriented Development Kevin M. Sherman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)588 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Ecotourism developments are becoming popular worldwide. The term is being used by those who may not fully understand its implications, yet still wish to exploit the concept's popularity. One of the ways an ecotourism operator's true intent is revealed is through their choice of wastewater treatment. A historically important and ecologically unique island is being developed in Northwest Florida using ecotourism principles. Distributed wastewater clusters are being installed with fixed film treatment and drip irrigation. Central to these decisions was the preservation of the numerous palm trees found throughout the island. A pretreatment system using the recycled husks of coconuts was chosen to treat wastewater from 26 single‐family cottages, a restaurant, and bar. This paper provides information on the design concept and treatment train of this fixed film treatment system. The paper concludes with an update of the longevity of media from the longest continually operating coir fiber system in the United States.

Select this Article		Water Supply Industry Course Correction Required John A. Kliem, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)589 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract Water is an essential ingredient for life. Our current pricing system does not reflect the value of water nor account for its scarcity. Current water rates are inefficient and subject to government subsidies resulting in wasteful water usage practices. Additionally, the inefficiencies in the market place act to discourage competition and improved water practices. Policies to internalize the externalities inherent in our water rates would help make the market more efficient as well as changes to the tax code to allow for tax exempt status for private debt for domestic firms engaging in water supply projects. This improvement would improve domestic competition in the marketplace.

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DEBRIS FLOW HAZARD ANALYSIS AND MODELING

Select this Article		Associated Disasters to the Debris Flows Guillermo Cardoso‐Landa ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/41036(342)590 Online Publication Date: 22 July 2009 Full Text: \| Download PDF
	+ -	Show Abstract In this article some of the disasters associated to the presence of the debris flows are described briefly happened in some countries of the world in recent years, which have been observed and, in some occasions, measures its fundamental characteristics, for example: The United States, China, Japan, Italy, Taiwan, Central Asia, Germany, Switzerland, Russia, the Philippines, the Ukraine, Canada, Brazil, Ecuador and Venezuela. In the country of Mexico have appeared great amount of debris flows in the recent years, many of them in the Mexican trans‐volcanic axis and coastal mountain ranges, such as the happened ones in Popocatepetl volcano, the volcano Pico de Orizaba, the volcano Nevado de Toluca, mountains of Puebla, in Acapulco, Gro., in the city of Tijuana, B.C. and in the coastal mountain range of Chiapas and Oaxaca, to only mention those that have produced important disasters in recent times. In the article the characteristics of the disasters produced in different regions from Mexico are also described. To identify the mechanisms that they involve to the solid material within a liquid flow, it is necessary to analyze the roles played by the several operating forces in the genesis of the movement in a debris flow. The developed approaches to date are the following ones: model of stability of infinite slope, approach of Shields, approach of Takahashi and recent developments. In order to be able to apply the previous models it is necessary to have very great information of diverse points on the land, with which a calculation mesh forms, therefore is essential to develop a GIS in the analysis site. A model appears in the complete article to determine the characteristics in the zone of beginning of a debris flow, which includes the development of a SIG.

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Experimental Analyses of Sedimentation in the Slit Dam Reservoir

Mohammad Ebrahim Banihabib and Ehsan Bahram