Jump to Content

Increase text size Decrease text size

Search Content Type

Search
Advanced Search

Proceedings

Search Issue | RSS Feeds

RSS

Examining the Confluence of Environmental and Water Concerns Proceedings of the World Environmental and Water Resources Congress 2006

May 21–25, 2006 Omaha, Nebraska, USA

Editor(s): Randall Graham

Buy this book

SECTION LISTING

Add

Add Items to Cart

View

View Items in Cart

SELECTED: Export Citations | Show Only | Show All | Show/HideHide Summaries | Add to MyArticles | Email

back to top

ADAPTIVE MANAGEMENT APPLICATIONS AND TECHNOLOGIES

Select this Article		Role of Information and Communication Technology in Adaptive Integrated Water Resources Management Tilak Raj Kapoor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)1 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract IWRM is well recognised globally and needs not much of introduction and recently adaptive management of water resources has gained popularity in tune with other fields where adaptive management has shown encouraging results. This paper gives an introduction of Integrated Water Resources Management in Adaptive Management context and focuses on Information and Communication Technology (ICT) Scenario that can be effectively used for Adaptive Integrated Water Resources Management. It also examines the practical issues that are involved in implementation of ICT for adaptive IWRM. The paper briefly discusses recent advancements that have made it possible to address rural areas and scattered locations that have major share of water consumers and tries to establish that most of the underlying problems in effective adaptive IWRM are due to inability to capture data from remote scattered locations over large geographical areas and also in effective implementation of communication that makes core of feedback and participation mechanism. Recent advancements in communication technology have made it possible to effectively use adaptive management practices for integrated water resources use.

Select this Article		Spatial Distribution of Groundwater Availability for Various Pumping Scenarios in Savannah Region Elcin Kentel and Mustafa M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)2 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Long‐term pumping from the Upper Floridan Aquifer (UFA) in the Savannah region, Georgia has lowered groundwater piezometric heads significantly. This resulted in salt water intrusion and brackish water contamination of the aquifer at Hilton Head Island, S.C. The aquifer is a primary source of drinking and industrial process water in the region, thus, various categories of users apply for groundwater withdrawal permits. The Georgia Environmental Protection Division (EPD) wants to develop a long term groundwater management plan which will protect the UFA from further salt water intrusion and also allow additional groundwater withdrawals from the aquifer. To achieve this goal, EPD first developed an “Interim Strategy for Managing Salt Water Intrusion in the Upper Floridan Aquifer of Southeast Georgia (EPD 1997)”. In this interim strategy, EPD has identified an area for enforced protection near the City of Savannah. Thus, since 1997, EPD has not issued permits for groundwater withdrawal from the UFA in the northern‐capped area unless such water is reallocated from a permit reduction elsewhere within the northern‐capped area (EPD 2004). EPD also initiated a program called Coastal Sound Science Initiative (CSSI) to generate data and information for developing a plan for managing salt water intrusion (EPD 2005). EPD's goal was to find answers for various questions related with the salt water intrusion problem in the region. Two of these questions were: (1) Can areas having minimal impact on salt water intrusion be identified and what amount of water can be obtained from them?, and (2) What are the other fresh water sources in coastal Georgia and what amount of water can be obtained from them? In this study, we proposed a coupled simulation‐optimization model to determine spatial distribution of additional groundwater availability within the Savannah region. We used this model to investigate spatial distribution of groundwater availability for various management scenarios, such as groundwater is withdrawn from the Lower Floridan Aquifer (LFA) from the UFA, or from the LFA and the UFA simultaneously (UFA+LFA). The results obtained from this analysis will be useful in answering the two questions posed by EPD and also will provide preliminary guidance in long term management and planning goals.

Select this Article		Adaptive Infrastructure Management for Environmental and Water Resources: A Conceptual Approach Wayne E. Woldt and Mohamed F. Dahab ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)3 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper outlines an approach to the development of adaptive management as a tool in the environmental and economic sustainability of community water supply systems by providing a framework to incorporate information into critical policy decisions. Adaptive management seeks to provide optimal management scenarios of water systems. The specific elements in the development of this approach rely on the deployment of a real‐time monitoring and predictive modeling framework using sensor networks, soft computing and information systems; the development of risk‐cost analysis methodology for water systems management under uncertainty; and the development of a conceptual approach for multi‐scale adaptive management of wastewater treatment facilities. The approach relies heavily on the definition of the role of emerging sensors and sensor networks, soft computing, uncertainty analysis, and advanced information systems.

back to top

SOCIO‐ECONOMICS IN ADAPTIVE MANAGEMENT

Select this Article		Tracing Factors Affecting the Adoption of Water Markets — Some Australian Experiences Henning Bjornlund ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)4 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper examines evidence of the factors affecting the adoption of water markets within Australia's largest irrigation district, the Goulbum‐Murray Irrigation District in Northern Victoria. The district is unique for the purpose of this analysis for a number of reasons: (1) irrigators are supplied by two main systems with very different supply reliability, (2) parts of the district have a high proportion of land suffering from soil degradation and salinity with low value production while other areas have better soils and higher value production, (3) market restrictions have been eased over time and varies across the district, (4) the district has experienced severe drought over the last six years, and (5) there are two different types of irrigators within the district, those supplied by the district infrastructure and those pumping their own water directly from the rivers with slightly different entitlements. The paper uses the trading and entitlement registers to analyze the trading behavior of all farm businesses during the first 13 years of trading both in the market for water entitlements and water allocations. Originally markets were adopted most extensively in the area with the largest potential financial tradeoffs between high and low value water users and irrigators with poor and good soils, while in the other parts of the district the main driver of market participation has been scarcity and policy changes.

Select this Article		Planing Different Construction Strategies to a Proposed Protection to Reduce the Cost and Improve the Shoreline Shape M. I. Balah and S. El‐Serafy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)5 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, the effect of the construction strategy on the final cost (of a shoreline protection system) and the shoreline shape, was investigated. A protection measure, which was designed to protect Sama El‐Arish village, along the Mediterranean Sea at El‐Arish, Egypt, was considered. This system is a 3‐graded length permeable rubble groins spaced at different distances supplied with nourishment at the down‐drift, at the East, Balah and El‐Serafy. Different strategies were planned. Each strategy was simulated. The simulation modeled the construction phases of each strategy. Based on the modeled construction phases, the strategies were economically evaluated and compared to the originally proposed designed system. Also, the effects of the different construction strategies on the shoreline shape were evaluated and compared to the originally proposed designed system. The comparison showed the effect of the construction strategy on the final cost of the structure and the shoreline shape.

back to top

STORMWATER I

Select this Article		An Update on Draft ASCE Monitoring Guidelines for Monitoring Stormwater Gross Solids Betty Rushton, Ph.D. and Gordon England, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)6 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Historically, evaluations of stormwater Best Management Practices, (BMPs), have focused on dissolved and suspended pollutants because the sampling methods were adapted from people's experience with wastewater treatment plants. Therefore, pollutants were sampled in the influent and effluent water column using grab samples or autosamplers, and flow measurements were made using velocity or weir measurements. But, stormwater pollutants differ from wastewater by being intermittent in nature and often having high volumes of gross pollutants in the storm runoff that can not be measured using autosamplers and standard techniques. New methods are being developed that measure gross pollutants in addition to the pollutants in the water column.

Select this Article		Development of Urban Storm Sewer Optimal Layout Design Model Considering Risk Sukhwan Jang, Larry. A. Roesner, Ph.D., P.E., F. ASCE, and Daeryong Park ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)7 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Rapid expansion of urban area since 1970's in Korea has caused the difficulties to discharge the flood in urban area watershed. Building the rational and optimal urban sewer network in urban area is very important to overcome the flood disaster. Sewer network installation needs two important requisites; the first is runoff analysis including design discharge and the second network layout design optimized economically. Many researches for runoff analysis as well as efforts to attenuate peak flows in urban watershed have been doing well. But layout design technology, relatively, has less devoted to develop network system or assessment methodology. What is interested in sewer layout design nowadays is not only how to discharge peak flow but also how to set up economic layout condition with results of simulated design discharge. This study aims at developing simulation model which might come up with the optimal condition of pipe capacity, slope, water depth and return cost in terms of least cost optimization in urban sewer layout design according to design discharge. In order to evaluate the risk at each state, first order second moment approximation was adopted to uncertainty analysis in the risk‐reliability relationship, which would be able to calculate the risk cost of the element. And DDDP (Discrete Differential Dynamic Programming) which is application of DP (Dynamic Programming) is used as an optimization technique in the sewer layout design. C‐language was used to code the model and analyzed node‐link structure for manhole‐sewer pipe. This model was applied to a newly developed resident area in Ulsan, Korea to assess the installed sewer network layout. As a result, the method in this study could suggest the more optimal condition to about 9% attenuation in terms of return cost considering risk.

back to top

STORMWATER II

Select this Article		Propagation of Surcharge Conditions in Flowing Sewers Jose G. Vasconcelos and Steven J. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)8 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Previous experimental investigations on the issue of flow regime transition from free surface to pressurized flow in stormwater sewers have introduced extreme conditions to generate pipe‐filling bore fronts. These conditions include the admission of large inflow into still water conditions and sudden flow blockage in a pipeline. It is unclear whether the results of these experiments are representative for flow regime transition events in actual flowing sewers. This paper summarizes an experimental investigation in which pipe‐filling bore fronts were generated by introducing large inflows in sewers initially in flowing conditions with drawdown profiles due to a free overfall at the downstream end. This condition is perceived as a more representative scenario in which flow regime transition events would occur. Pressure and velocity measurements were performed and the results compared well with predictions from a flow regime transition model.

Select this Article		Mechanisms for Air Pocket Entrapment in Stormwater Storage Tunnels Jose G. Vasconcelos and Steven J. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)9 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The behavior of stormwater systems can be greatly altered by the presence of air pockets within the pressurized portion of the flow. While rapid filling conditions in stormwater storage tunnels can result in air pocket entrapment, the mechanisms for this phenomenon have not been studied systematically to date. This paper summarizes an investigation conducted at the University of Michigan on an experimental setup that reproduces the essential features of a below grade storage tunnel. Various filling scenarios were tested in which the filling rate, initial water depth and ventilation configurations were varied. Different and previously unreported mechanisms for air pocket entrapment were identified. For the conditions investigated in the experiments, the formation of air pockets was relatively common.

Select this Article		Conveyance Analysis of Chicago's ‘Deep Tunnel’ System Nils Oberg, Corrie E. Bondar, Matthew A. Hoy, A. M. ASCE, and Arthur R. Schmidt, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)10 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Tunnel and Reservoir Plan (TARP) is a system of 175 kilometers of deep underground tunnels and large reservoirs designed to capture and store combined‐sewer overflows of greater Chicago. Conveyance studies in sewer systems often discretize the sewer into reaches delimited by manholes or junctions, effectively ignoring the water‐surface profile within a pipe. Another approach is to performing backwater calculations, on small spatial steps, for every flow condition in the system. This is not unreasonable for problems such as flood‐plain studies, where only a few flows are considered. However, a much larger range of flows is possible when considering operational decisions for a sewer system. Previous research demonstrated the effective use of the hydraulic performance graph (HPG) for open‐channel capacity determination. The HPG stores the results of backwater calculations for a reach so that these calculations do not need to be repeated. The HPG has been extended from that for open‐channels to also describe pressurized flow in sewers. This paper describes a procedure that uses the HPGS for each reach of a sewer system, along with a description of the junction losses, to describe the conveyance of any bottlenecks in a system of sewers or tunnels for free‐fsurface, pressurized, or mixed flow conditions. This method has been integrated into a geographic information system (GIS). The GIS stores the topology and geometric description of a pipe network, the HPGs for all reaches in the system, and coefficients needed to estimate junction losses. This allows for visualization of bottleneck locations and flow conditions throughout the system for any flow configurations and operation plan.

back to top

STORMWATER III

Select this Article		Development of Fuzzy Rules Based System for Rainfall‐Runoff Modeling Ivan Rivas and Larry A. Roesner, Ph.D., P.E., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)11 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The rainfall runoff process is one of the most complex and non‐linear real world problems in water resources and hydrology. The same amount of precipitation could generate different runoff over the same watershed depending on, for example, soil humidity conditions. An attempt was made in this paper to develop a fuzzy rule‐based routine. The main objective was to develop a fuzzy rule‐based system to forecast the peak flow rate (Q_max) over a watershed for six different storm events. The developed fuzzy rule system was applied to a drainage basin in North Carolina, in which SWMM (EPA Storm Water Management Model) simulations provided training sets to develop the fuzzy rule system. Geographic Information Systems (GIS) were employed to get the information on watershed characteristics. The resulting fuzzy‐rule system was assessed by comparing its responses with the modeling results in EPA‐SWMM 5.

Select this Article		GIS‐Based Support System for Modeling Chicago's “Deep Tunnel” System Corrie E. Bondar, Matthew A. Hoy, A. M. ASCE, and Arthur R. Schmidt, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)12 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Tunnel and Reservoir Plan (TARP) is a system of 175 kilometers of deep underground tunnels and large reservoirs designed to capture and store combined sewer overflows of greater Chicago. Construction of the system began in the 1970's and currently, the tunnels are nearing completion and excavation of the reservoirs is underway. The hydraulic behavior of the system is inadequately understood, particularly the transition from gravity to surcharged flows. Because of the potential to form hydraulic transients under these conditions, an improved description of the hydraulic behavior of the system is a prerequisite to determining operational rules that better utilize the capacity of the system. In order to gain a better understanding of the hydraulic behavior in the tunnels, models are currently under development to model steady flow, unsteady flow, and hydraulic transients in the as‐built system. A geographic information system (GIS) has been developed to provide a framework that facilitates managing the data, visualizing the output, and integrating the different modeling tools needed to describe this system. Of particular interest in this work is use of the GIS to store model results describing the steady‐flow hydraulics of the system for the range of possible flow conditions. These stored descriptions of the hydraulics are used by more sophisticated models of the hydrodynamics of the system, thereby eliminating repetitive calculations that otherwise would be necessary for every time step in the unsteady‐flow models. In addition, the GIS makes the modeling process more efficient by allowing multiple models to obtain necessary information, such as geometry and hydraulic coefficients, about the entire network from a single database. This allows changes made to the database to be quickly reflected in the models. Finally, the GIS provides an effective means of storing and displaying the model output clearly and concisely so that an assessment of the system performance can quickly be made.

Select this Article		Unsteady Flow Routing in Sewers Using Hydraulic and Volumetric Performance Graphs Matthew A. Hoy, A. M. ASCE and Arthur R. Schmidt, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)13 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The hydraulic performance graph (HPG), which consolidates all the backwater profiles of a channel reach into a family of delivery curves, provides a summary of the momentum of flow for the entire range of conditions. Earlier research by Gonzalez‐Castro (2000) demonstrated that the approximation to the momentum of flow provided by the HPG can be coupled with an implicit finite‐difference solution of the continuity equation to route unsteady flows through simple, unbranched channel reaches with accuracies approaching those of dynamic wave models. The model described in this paper adds to the earlier work by introducing the volumetric performance graph (VPG), which describes the volumetric water storage in the reach for the range of flow conditions computed in the HPG. The VPG provides a summary of the conservation of mass in the reach, replacing the finite‐difference solution used in the earlier work. Instead of numerically solving the Saint‐Venant equations in a coupled manner, as is typically done in unsteady flow‐routing, the momentum equation is solved a priori and summarized in the HPGs, which are then used to describe the momentum at each time step. The description of momentum from the HPGs is coupled with the description of continuity from the VPGs to simulate the routing in a stepwise‐steady manner. Benefits of this type of modeling include: (1) computation time — the momentum equation is solved for a range of conditions and summarized, as opposed to solving at each time step, and (2) precision — momentum is solved at fine resolution, but summarized to a coarser spatial resolution.

back to top

WASTEWATER I

Select this Article		Rapid Determination of Wastewater Sludge Dewatering Performance Using Capillary Suction Timer Jianpeng Zhou, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)14 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The handling of wastewater sludge is a significant challenge, because the amount of wastewater sludge is large, the handling, processing and final disposal of sludge are difficult and expensive, which could count for 40% of total operational costs of a wastewater treatment facility. It is important to determine rapidly the performance of sludge dewatering (solids recovery and sludge cake dryness) and to optimize timely the dosing of the conditioning chemical, so the operational cost can be reduced. This paper reports findings from a recent study that investigated the feasibility of using capillary suction timer (CST) as a tool to determine the performance of sludge dewatering. This laboratory research studied sludge samples taken from three different sludge treatment processes: mesophilic aerobic, mesophilic anaerobic, and thermophilic aerobic digestion. Two polymers, carrying high and low cationic charges, were used to condition a thermophilic aerobically digested sludge sample. Conditioned sludge was centrifuged at 2,000 rpm for 20 minutes. Experimental results revealed that when unconditioned sludge samples of various sources are compared, CST was not an appropriate indicator to predict quantitatively dewatering performance of sludge samples; when conditioned sludge samples (dosed by polymer at various rates) from a single source are considered, quantitative relationship exists between the solids concentration in the supernatant of the centrifuged sludge and CST of the uncentrifuged samples. Findings from this study suggest that CST can be used as an efficient tool to assist wastewater operators to assess rapidly the performance of dewatering process and make prompt decision for efficient and cost‐effective operation of the dewatering process, which would help to reduce the costs of wastewater treatment facility operation.

Select this Article		Potential Utilization of Sugar Industry Waste for Removal of Color from Textile Industry Effluent P. Aadhar, J. Vishal, and M. Mausumi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)15 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The aim of this research was to study the utilization of bagasse (sugar industry waste) as adsorbents for removal of red and violet dyes. The dyes namely red C4G and violet 5BN used in textile industry for polyester and silk coloring respectively. The sorption of these dyes to bagasse and the characterization of the adsorptive property of the biomass for color removal were investigated by batch experiment. The influence of operating conditions like time, initial dye concentration and pH on process performance was also evaluated. Dye removal by bagasse was influenced by the pH of the solution, initial dye concentration, and time. Kinetic studies showed that the concentrations of C4G decreased very rapidly initially and remained nearly constant after 80 minutes but for 5BN rate of reaction was comparatively slow and after 240 minutes the concentration reached constant value. The maximum removal of C4G and 5BN on low‐cost bagasse adsorbent was at pH 5.5 and pH 2 respectively. Maximum C4G and 5BN removal capacity of the bagasse was found 3.24 mg / g and 0.51 mg / g at 200 mg / l initial dye concentration. Kinetic experiment was conducted and validated for Lagrange's pseudo‐first and second order system. It was observed that for C4G dye the reaction follows pseudo‐second order rate constant and for 5BN dye reaction follows pseudo‐first order rate constant. The Langmuir and Freundlich adsorption isotherm model were used to describe the equilibrium behavior of the system. The efficiency of the sorption was 99% and 76% for C4G and 5BN respectively.

Select this Article		Evaluation of Bench Scale SBR for Removal of Nutrients from Domestic Wastewater Sudevi Basu and B. Manoj Kumar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)16 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Wastewater contains organic matter, nutrients like nitrogen and phosphorus, pathogens and other pollutants and its discharge in water bodies causes environmental problems like eutrophication, fish kills and odours. Research has been carried out over the years to find effective biological treatment methods to remove nutrients and in this direction the sequencing batch reactor (SBR) has demonstrated good potential for complete removal of phosphorus and nitrogen from domestic wastewater. Bench scale studies on SBR were carried out to assess its ability to develop phosphorus accumulating organisms (PAOs) in short period of time with seed material taken from sludge of septic tank and feed used was synthetic wastewater. Various researchers had reported that several months were taken to develop enhanced biological phosphorus removal (EBPR) sludge whereas in this study it was found that in a short duration of 21 days, the COD removal was 73.4% in anaerobic phase while the phosphorus removal yield (PRY) was 92%, which indicated that PAOs were grown in sufficient numbers. After enrichment, the SBR was fed with raw domestic wastewater which contained COD (260 mg/l), ammonia nitrogen (59 mg/l) and phosphorus (15.3 mg/l). The effluent at the end of the SBR cycle contained less than 15 mg/l of COD, ammonia nitrogen of less than 1 mg/l, nitrate nitrogen in the range of 10 to 11 mg/l and phosphorus in the range of 0 to 1.5 mg/l. The denitrification observed was 100% in the anaerobic phase. To remove nitrate nitrogen completely, an anoxic batch reactor was started and the final effluent contained COD of less than 20 mg/l, nitrate nitrogen less than 1 mg/l, phosphorus concentration less than 2.2 mg/l and ammonia nitrogen concentration of less than 2 mg/l. Kinetic study was done to determine the rate at which microbes treat wastewater to remove nutrients and it was observed that COD uptake was 0.058 mg COD/mg VSS within one hour from the start of anaerobic phase and corresponding phosphorus release was 3.49∗10⁻⁴ mg phosphorus/ mg VSS. The denitrification rate observed was 3.40∗⁻⁴ mg nitrate nitrogen/ mg VSS. The kinetic study also showed the phosphorus uptake was 5.04∗10⁻³ mg phosphorus/ mg VSS and the nitrification was 3.33∗10⁻³ mg ammonia nitrogen/ mg VSS in the first one hour of aerobic phase.

Select this Article		Bench‐Scale Digestion Studies R. O. Mines, Jr., L. W. Lackey, and A. J. Butler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)17 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Four, 1‐L bench‐scale digesters were operated for 25 days to evaluate the effectiveness of oxygen and ozone on sludge stabilization. Each digester contained waste activated sludge generated from the Rocky Creek Wastewater Treatment Plant (WWTP) in Macon, Georgia. Two of the digesters were sparged with air and the remaining two digesters were sparged with ozone. The following parameters were measured frequently during the bench‐scale study: pH, total and soluble chemical oxygen demand (COD), temperature, total and volatile solids, and total suspended and volatile suspended solids. The kinetics of volatile suspended solids (VSS) reduction was determined and average first order degradation constants (K_D) for the aerobic and ozonated digesters were 0.0824 days⁻¹ and 0.108 days⁻¹ respectively, indicating that ozone was more effective at destroying VSS than oxygen. Total chemical oxygen demand (COD) removals averaged 37% and 64%, respectively for the aerobic versus ozonated digesters. Soluble COD (SCOD) concentrations in the digesters increased from 0 to 15.5 mg/L in the aerobic digesters and from 0 to 293.5 mg/L in the ozonated digesters due to solubilization of the biological sludge solids. Approximately 1.82 mg of oxygen was required per mg of total volatile solids (TVS) destroyed. Average ozone dosages observed in this study were 2.6 and 2.8 mg of O₃ per mg of total solids (TS) destroyed for ozonated digesters 1 and 2, respectively.

back to top

WASTEWATER II

Select this Article		Experimental Research on Treatment of Housing Estate Wastewater by Non‐Residual Sludge Hydrolytic Acidification Process Hong‐jun Han, Wen‐cheng Ma, and Dan Zhong ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)18 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract With the increasing of the sewage delivery of housing estate, the quantity of residual sludge was increasing at the same time. The proportion of investment and operation cost used for treatment of residual sludge was higher in total cost. That brought many difficulties in treatment of housing estate sewage. In this paper, the non‐residual sludge hydrolytic acidification process was taken to treat housing estate sewage. This internal cycle system was composed of medium‐temperature anaerobic acidification reactor, hydrolytic acidification tank and contacting oxidation tank. Aerobic and anaerobic microorganism died and can be degraded continuously through a variable anaerobic‐aerobic process. In this way, residual sludge produced in aerobic process could be digested thoroughly. Test showed that operation of acidification reactor had better effect under condition of temperature 34 degrees C, HRT 1.5 day, PH 5.5∼6.0 and residual sludge can be decreased or zero emission. In this paper design and effective control of acidification reactor are also discussed.

Select this Article		An Innovative Geocentric Decision Support Solution to Comprehensive Planning, Design, Operation, and Management of Urban Drainage Systems Paul F. Boulos, Misgana K. Muleta, Chun‐Hou Orr, and Jun Je Ro ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)19 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Geographic Information System (GIS) is quickly becoming a critical component to develop and sustain asset management for today's wastewater utilities as most of their data is geographically referenced. This technology offers sophisticated data management and spatial analysis capabilities that can greatly improve and facilitate urban drainage infrastructure modeling and analysis applications. This paper presents a comprehensive GIS‐based decision support system that integrates several technologies for use in the effective management of urban stormwater collection systems. It explicitly integrates ESRI ArcGIS geospatial model with advanced hydrologic, hydraulic, and water quality simulation algorithms, nature‐based global optimization techniques including genetic algorithms for design and calibration of stormwater management models, automated dry weather flow generation and allocation, and automated subcatchment delineation and parameter extraction tools to address every facet of urban drainage infrastructure management. The geocentric interface allows seamless communication among the various modules. The resulting decision support system effortlessly reads GIS datasets, extracts necessary modeling information, and automatically constructs, loads, designs, calibrates, analyzes and optimizes a representative urban drainage model considering hydrologic and hydraulic performance requirements. It also makes it easy to run, simulate and compare various modeling scenarios,' identify system deficiencies, and determine cost‐effective physical and operational improvements to achieve optimum performance and regulatory compliance. These combined capabilities provide favorable geospatial environment to assist wastewater utilities in planning, designing, and operating reliable systems and in optimizing their capital improvement programs.

Select this Article		A Framework for the Removal of Bacterial Contamination from UASBR Effluent Anju Pant and Atul K. Mittal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)20 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sewage in India is treated to primary or secondary level of treatment. Recently, standards for the indicator micro‐organisms for the effluents from the sewage treatment plants (STPs) have been proposed. Selection of appropriate technology for the augmentation of the existing STPs is under consideration. Many of these plants are based on the Upflow Anaerobic Sludge Blanket Reactor (UASBR) technology. The fecal coliform count in UASBR effluent was found to be of the order of log cycles of six, which exceeds the WHO guidelines by an order of 3. The evaluation study of pilot plants had been carried out at two different UASBR based sewage treatment plants in India. One of the pilot plants is based on chlorination (2 MLD), and other is based on fixed film aerobic process (1 MLD, biotower). Evaluation study consisted of onsite monitoring of the COD and fecal coliform over a period of 3 months. Samples were collected from the inlet and outlet of the plant. It is contemplated to select an appropriate disinfection technology for the treatment of the effluents from UASBR based sewage treatment plants so as to meet the biological quality standards. The results show that the fecal coliform removal is up to 98.2 and 100% for biotower and chlorination respectively. Removal of COD has also been determined.

Select this Article		Statistically Based Design of Wastewater Treatment Plants (WWTPs) Using Monte Carlo Simulation of Activated Sludge Model No.1 (ASM1) Jinsheng Huo, Yan Jiang, William L. Seaver, R. Bruce Robinson, and Chris D. Cox ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)21 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract To deal with uncertainties in wastewater treatment plants (WWTPs), high safety factors are commonly adopted in the traditional plant design procedure, which may lead to an over‐designed plant. In this paper, the Monte Carlo method is applied in both steady‐state and dynamic simulations of the activated sludge model No.1 (ASM1) to quantify the uncertainty of the plant performance. Statistical analysis of the plant effluent indicates that it has a wider distribution, which demonstrates the motivation for using conservative design assumptions in the first place. However, we suggest that a better design approach is proposed based on an acceptable risk of effluent violations. To support this design approach, we will present methodologies for estimating the frequency of occurrence effluent violation based on 7‐day and 30‐day average effluent permit levels. Armed with this type of information, engineers, regulators and the community can more realistically evaluate the trade‐off between risk and cost.

back to top

WASTEWATER III AND CONSTRUCTED WETLANDS

Select this Article		Evaluation of Constructed Wetland as Secondary Wastewater Treatment Source for Tertiary Wastewater Treatment and Reuse System Marwan Haddad ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)22 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes an investigation into the treatment effectiveness and feasibility of constructed wetland (CW) system as a secondary wastewater treatment system, as an economic agricultural producer, and as a pretreatment phase for an ultrafitration/reverse osmosis UF/RO tertiary treatment plant. The treatment system consists of one vertical-flow infiltration CW cell (150 m² in surface area, 112.5 m³ in volume) and two settling basins (one before and one after the CW); gravel, coastal sand, and almond shells were used as CW media. The CW was vegetated with various plants including spineless cactus. Samples were analyzed for total plate count, turbidity, total nitrogen, total phosphorus, total suspended solids, biochemical oxygen demand, chemical oxygen demand, temperature, conductivity, and pH. The CW operation indicated a significant reduction in influent water quality and proved to be of suitable for smooth operation of the UF/RO pilot plant. High biomass growth was observed on the spineless cactus and banana and little or negative growth was obtained on other planted crops.

Select this Article		Micro‐ and Macro‐Environmental Studies in Scirpus validus Rhizosphere: Engineering Significance Achintya N. Bezbaruah and Tian C. Zhang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)23 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The role of wetland plants in the treatment of wastewater was investigated. The research was carried out in the backdrop of conflicting reports about the role wetland plants play in wastewater treatment. The plants' ability to release oxygen through their roots in wastewater environment was investigated in subsurface flow wetlands. The research investigated the role of aerobic and anaerobic processes in constructed treatment wetlands. Oxygen release by the wetland plants has been reported by researchers. One of the most recent studies have reported quantification of wetland plant oxygen release through the use of microelectrodes. However, the microelectrode measurement method had its inherent drawback of possible under or over estimation of oxygen release by wetland plants. This research is an endeavor to model a field wetland based on the assumption that wetland plants do not release enough oxygen for use in biochemical oxygen demand (BOD) removal. The wetland was modeled as an aerobic‐anaerobic system. The model takes into account all the possible mechanisms of oxygen addition and consumption. These mechanisms include atmospheric reaeration, plant oxygen release, wastewater oxygen demand, and biomass oxygen demand. The modeling results indicated that ∼ 65% BOD removal occurs aerobically and rest is removed anaerobically.

Select this Article		Column Tests for Simulation of Phosphorus Fate and Transport and Evaluation of Life Expectancy of a Wastewater Land Treatment System Tian C. Zhang, Mohamed F. Dahab, Germana Nunes, and Rao Surampalli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)24 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Currently, a reliable method for predicting the remaining life expectancy (RLE) of a land treatment system is not available. Hu (2005) concluded column studies by intermittently loading columns with a high influent P concentration to simulate P adsorption capacity and the low hydraulic loading rate conditions in the field. The objectives of this study were to: (1) further verify Hu's methodology, (2) evaluate P fate and transport in these columns, and (3) improve the existing model for predicting the RLE. Column tests were conducted under different influent P concentrations (e.g., 3000, 1000, 500, and 100 mg‐P/L), and P breakthrough in each column was monitored. The results indicate that the predictions of the RLE of the Muskegon system were very similar for the three different influent P concentrations, but varied with soil types. Therefore, loading a short column packed with field soil intermittently with a high influent P concentration may be an efficient way to accelerate the process that might occur in the field and to predict the life expectancy of a wastewater land treatment system.

Select this Article		Modeling Biofilm Dynamics in a Constructed Wetland Wastewater Treatment System Wayne Woldt, Ram Marahatta, Dennis Schulte, and Mohamed Dahab ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)25 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A review of modeling approaches for simulation of wastewater treatment in vegetated subsurface bed (VSB) systems is presented. A multi‐scale biofilm‐based model that includes substrate utilization both in bulk liquid and the biofilm is formulated and described. The model accounts for transport of substrate in the liquid phase, and growth and decay of biomass in suspension and in the biofilm. Dynamic changes in porous media hydraulic flow, combined with attachment and detachment of biomass are considered. Natural precipitation and evapotranspiration are also considered. Field application of the model along with a survey of the parameters is presented and performance of the model for simulation of organic matter removal and clogging is assessed. The mechanistic model simulates the performance of a constructed wetland treating wastewater very well, and has potential for use in design of constructed wetland systems.

back to top

WATER DISTRIBUTION SYSTEMS

Select this Article		Minimizing Leakage Rates in Water Distribution Networks through Optimal Valves Settings H. A. Al‐Hemairi and R. H. Shakir, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)26 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this study, a model has been developed to optimize the operation of flow control valves according to variable demands under a selected water leakage percentage. A non‐linear optimization objective function is used to minimize the differences between the available nodal pressures and those required. This objective function is subject to constraints; represent assigned minimum and maximum limits for both valve settings and allowable head deviations, in addition to constraints represent the application of the continuity equation at each node and the application of energy conservation law at each loop of pipes. The objective function is further modified by adding penalty of the statistical coefficient of variation of nodal pressures. This model has been verified using a network example presented by previous researchers in the same field and then applied on a case study network in Iraq. The results of the case study indicate the capability of the system to obtain optimal valves settings for the selected input data.

Select this Article		Leakage Management for Water Distribution System in GIS Environment Abdollah Ardeshir, Mehdi Saraye, Farhad Sabour, and Kourosh Behzadian ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)27 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Leakage control is one of the most important issues in water networks. This paper presents leakage management and how to organize and analyze a water distribution system for leakage purposes. Also various aspects of management of water supply networks are depicted in order to provide integrated hydraulic model in (Geographical Information System) GIS. These consist on determination of required data structures and, how to supply and reintegrate the information in GIS. The specification and applicability of the hydraulic model, in GIS for leakage management in urban water system, is studied with practical project in Saveh city of Iran. These are accomplished using Arcview as GIS base and EPANET software for hydraulic modeling and link between the above programs is DC water extension. Based on the analyses carried out and using the relationship between hydraulic and physical characteristics of distribution system, leakage indices have been calculated. The results can provide valuable management guidelines to identify leakage location in the system. Also a flowchart of data management and analyzing hydraulic systems in GIS environment has been obtained that can be useful in any other process of such analysis.

Select this Article		A Comprehensive Water Audit of the San Antonio Water System Kelly Brumbelow, A. M. ASCE, Cheryl L. Linthicum, Sarah Meyer, S. M. ASCE, Kyle Murray, Dana Nichols, Gabriel Shelton, and Landon Yosko ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)28 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water accountability standards are increasing for many water utilities as supplies are progressively strained. Water demand for San Antonio, Texas, the eighth largest city in the United States, is expected to double by 2050. At this time, San Antonio is solely dependent upon groundwater, the majority of which comes from a capped withdrawal of the Edwards Aquifer. In addition to a full portfolio of water conservation policies, San Antonio Water System (SAWS) is undergoing a water audit using the standards and methodology of the International Water Association (IWA). This audit is being completed in anticipation of the Texas Water Development Board (TWDB) requiring audits of water purveyors starting in 2006. Successful application of the IWA method to SAWS infrastructure and management practices requires some adaptations to the audit procedure. Changes to the water audit methodology and new techniques for calculating audit components are presented.

Select this Article		Coupled Assessment of Water and Fire Systems Damages under Attack and Disaster Scenarios Elizabeth Bristow, S. M. ASCE, Lufthansa Kanta, S. M. ASCE, and Kelly Brumbelow, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)29 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water systems' vulnerability to natural disaster and terrorist attack has prompted extensive study of the probability and consequences of their potential failure. These systems are vital in their own right because they provide water for drinking, but they are also indispensable components of many cities' fire response plans. Water systems are also dependent on — or key inputs to — many of the other infrastructures that support daily life and efficient emergency response. Any risk assessment of water systems must therefore consider the importance of water systems' interdependence with fire response and other affected infrastructures. More investigation is needed on the effects of infrastructure interdependence on water systems' vulnerability. To highlight the importance of infrastructure interdependencies, a coupled model of water system performance and urban fire spread and suppression will be presented. The system's ability to suppress an urban fire under moderate damage to the water system will be modeled, and the consequences of this multi‐mode failure — disabled water system and urban fire spread — will be discussed. This coupled modeling approach allows diagnosis of water systems' potential vulnerabilities to multi‐mode attacks or failures (MMAFs) and development of possible mitigation strategies.

back to top

WATER TREATMENT I

Select this Article		Capability of Immobilized Mix Culture Technique as a Bio‐Eco Engineering for River Basin Management B. K. Pathak, F. Kazama, Y. Saiki, and T. Sumino ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)30 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Nitrogen removal capability of bio‐reactor systems were investigated in the laboratory in order to extend the treatment process for river basin management. Biomass from activated sludge was immobilized using gel and bio‐pellets were prepared. Three upflow bioreactors R1, R2 and R3 were packed with bio‐pellets, anaerobic granules, and mixture of bio‐pellets anaerobic granules and biodegradable plastic respectively. Comparing the performance of reactors, R1 demonstrated well at nitrification while R2 showed its capability in denitrification and R3 showed good performance in both nitrification and denitrification. Moreover, results showed that R3 removed 80% of incoming total nitrogen where as reactors R1 and R2 removed less than 60% of total nitrogen. Despite the effluent total organic carbon in all reactors was almost same, N removal process and rate in each reactor was different. It suggests that sources of biomass define the diversities of biomass in the reactors which ultimately guides the N removal process and rate as well. The developed system is wide applicable and has operational advantages in terms of efficiency, aeration cost, and biomass handling.

Select this Article		Chemically Induced Redox Reactions in Water Treatment: A Summary of Advanced and Direct Technologies George P. Anipsitakis and Dionysios D. Dionysiou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)31 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract It is impressive how lengthy the list of chemical technologies based on redox phenomena is and the treatment objectives one can achieve based solely on redox chemistry. This paper provides an overview of oxidation‐reduction processes used for the transformation and destruction of targeted water contaminants. The most important oxidation‐reduction reagents are further discussed here and classified in three general categories. Key characteristics of each technology are also underlined.

Select this Article		A Numerical Model for Petroleum Hydrocarbons Transported by Sediment Laden Flows in Open Channels Zhong Deyu, Yu Xuezhong, and Ding Yun ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)32 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Presented in this paper was a numerical model for the Petroleum hydrocarbons transported in sediment laden flows. The model was developed base on the basic equations of the two‐fluid model for sediment laden flows so that the fate and transport of either dissolved or particulate phase of PHs can be simulated without introducing partition coefficient. More important was that by invoking the two‐fluid model the model longer need the assumption that the particulate phase of PHs was under the same convection and diffusion effect as dissolved phase. Verifications by flume experiments were also presented in this paper. Comparisons between simulations and observations indicated that the model presented in this paper has a fairly good accuracy so far as the flume data were considered.

Select this Article		Continuous Flow Defluoridation Unit for Rural Water Supply Scheme of Fluoride Prone Areas H. S. Ramesh and M. Kamaraju ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)33 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract High level concentration of fluoride affects human health by causing incurable skeletal and dental fluorosis, non‐skeletal manifestation and combinations of above. Defluoridation techniques have been developed and implemented are not continuous and cost effective. At present there is an urgent need of having economically viable continuous flow defluoridation units for rural areas. This study evolves with a noval modification in the popular Nalgonda technique as a continuous flow economical defluoridation unit. Experiments on horizontal and vertical flow defluoridation filter baffles comprising of locally available materials like wood charcoal, medium coarse sand & brick jelly with Nalgonda chemicals revealed that the fluoride removal efficiency of 68% in the pH range of 7 to 8.5 for the maximum 4 mg/l of fluoride concentration has been observed. The economical analysis performed between the assumed extension of a particular comprehensive water supply scheme and the water supply scheme designed with the evolved continuous flow defluoridation unit costs only 26% of the general comprehensive water supply scheme. The independent defluoridation unit costs only 13% of the total cost of the proposed water supply scheme.

back to top

WATER TREATMENT II

Select this Article		Interactions between Halide Ions and Ammonia in Water under UV Light from Low Pressure Mercury Lamps Yvette Beckles and Vasil Diyamandoglu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)34 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The impact of low pressure UV lamps on the oxidation of ammonia (NH₃) in the presence of individual halide ions (bromide (Br⁻), chloride (Cl⁻) and iodide (I⁻) was investigated and revealed that the ions have the potential to accelerate ammonia photo‐oxidation. The process was found to be dependent on solution pH, the type of halide ion and the concentrations of halide ion and aqueous ammonia. Protons are released during the reaction while the halide ion concentrations remain unchanged. Nitrite (NO₂⁻) and nitrate (NO₃⁻) are produced as final stable nitrogen species, with the yield being dependent on the initial pH of the irradiated solution. NH₃ oxidation occurred with Br⁻ and Cl⁻ at all pH levels, but in the presence of I⁻ it proceeded only at basic pH. Sulfur hexafluoride (SF₆) was used as an electron (e⁻) scavenger to demonstrate that ammonia oxidation generates e⁻ in solutions containing halide ions. The process was confirmed with the formation of fluoride (F⁻) and sulfate (SO₄²⁻) ions.

Select this Article		An Efficient Numerical Scheme for Modeling Two‐Phase Bubbly Homogeneous Air‐Water Mixtures Arturo S. León, Mohamed S. Ghidaoui, Arthur R. Schmidt, and Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)35 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper focuses on the formulation and assessment of a second‐order accurate Finite Volume (FV) shock‐capturing scheme for modeling two‐phase water hammer flows using the single‐equivalent fluid approximation. The FV formulation of the proposed scheme ensures that mass and momentum are conserved. For achieving a second‐order rate of convergence for smooth transients (i.e., flows that do not present discontinuities), a second‐order boundary condition is implemented using virtual cells and the theory of Riemann invariants, which is similar to that used for the Method of Characteristics (MOC). Since the two‐phase flow governing equations when using the single‐equivalent fluid approximation are the same as the one‐phase water hammer equations (with exception that the pressure‐wave celerity is constant in the latter case), and because analytical solutions are available for the latter case, the numerical efficiency of the proposed model is tested using the one‐phase water hammer equations with constant pressure‐wave celerity. The validity of the single‐equivalent fluid approximation and the proposed scheme herein are verified with laboratory experiments. For one‐phase transient flows, numerical tests were performed for smooth and strong transients. For smooth transients, the results show that the efficiency of the proposed scheme is highly superior to the fixed‐grid MOC scheme with space‐line interpolation and another second‐order FV scheme. For one‐phase strong transient flows, the results show that the efficiency of the proposed scheme is highly superior to the MOC scheme, and significantly superior to the other FV scheme for coarse grids. For fine grids, the accuracy of the proposed scheme converges to that of the other FV scheme. For two‐phase water hammer flows, the results show good agreement between experimental data and the results of numerical simulations.

Select this Article		Microbial As (III) Oxidation in a Continuously Stirred Tank Reactor Yi‐Tin Wang, Arthon Suttigarn, and Aniruddha Dastidar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)36 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Microbial As (III) oxidation was investigated for 204 days in a continuous stirred tank reactor (CSTR) with a pure culture of Alcaligenes faecalis strain O1201 under a range of hydraulic retention times (12.8, 25.6, 51.9, 67.4, and 90.7 hours) and influent As (III) concentrations (1,000, 2,000, 4,000, and 8,000 mg/L ). Air was supplied through a gas diffuser to maintain a minimum level of dissolved oxygen of 2 mg/L throughout the entire operation. NaOH was fed into the CSTR to neutralize hydrogen ions produced during As (III) oxidation and maintained pH at 7±0.1. Temperature was maintained at 30±2 degrees C using a heating tape equipped with a temperature controller. Nine steady‐state operation conditions were obtained with near‐complete oxidation of As (III) for each phase.

back to top

CLIMATE, METEOROLOGY, AND WATER RESOURCES I

Select this Article		Decadal Precipitation Variations and Inflows into Fort Cobb Reservoir, Oklahoma Jurgen D. Garbrecht, Jeanne M. Schneider, and Michael W. Van Liew ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)37 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Changes in annual reservoir inflow and flood release volumes due to persistent multi‐year dry or wet periods were investigated for the Fort Cobb Reservoir. A time‐series analysis of the 1940–2004 annual precipitation revealed three dry and one wet period, called decadal variations. Corresponding strong variations were found in the reservoir inflow and flood release records. The sensitivity of watershed response, reservoir inflow and flood release volume to decadal precipitation variations suggested that water resources and water quality assessments in central Oklahoma should account for decadal precipitation variations. Along the same lines investigations based on numerical model simulations need to consider such climatic variations in the calibration, validation and application phase.

Select this Article		Pacific Oceanic/Atmospheric Variability and the Wind River Range Glenn A. Tootle, Thad M. Hunter, and Thomas C. Piechota ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)38 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A study of the influence of interdecadal and interannual Pacific oceanic / atmospheric variability on the Wind River Range (WRR), Wyoming is presented. The WRR is an unbroken 160‐kilometer barrier that is host to 63 glaciers, the largest concentration of glaciers in the American Rocky Mountains. Glacial recession over the past half century has resulted in an increased interest in the region. Instrumental datasets were obtained for unimpaired streamflow and snow water equivalent for stations in the Green River Basin (GRB — west slope of WRR) and the Wind‐Bighorn River Basin (WBRB — east slope of WRR). The phases (cold or warm) of Pacific [El Niño‐Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO)] oceanic / atmospheric phenomena were identified. Statistical significance testing of the datasets, based on the interdecadal and interannual oceanic / atmospheric phase (warm or cold), was performed applying the parametric t‐test test. The results show that the interannual ENSO phase influences streamflow and snow variability in the WRR and the interdecadal PDO phase influences snow variability during La Niña events.

Select this Article		El Nino — La Nina Implications on Flood Hazard Mitigation Richard H. French and Julianne J. Miller ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)39 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The effects of El Nino and La Nina periods on the maximum daily winter period depths of precipitation are examined using records from five precipitation gages on the Nevada Test Site. The potential implications of these effects are discussed.

back to top

CLIMATE, METEOROLOGY, AND WATER RESOURCES II

Select this Article		Does Downscaling in Space and Time Degrade the Dependability of Seasonal Climate Forecasts? J. M. Schneider and J. D. Garbrecht ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)40 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center issues total precipitation and average temperature forecasts for 3‐month periods for relatively large areas (forecast divisions are about 9 × 10⁴ km²). Incorporation of the climate forecasts into farm level decision support systems necessitates downscaling the forecasts to local and daily time scales. Since any measure of the skill of seasonal climate forecasts is expected to depend on scale (specifically, more skillful for larger areas and longer time periods), there is concern that downscaling will dilute current forecast skill, possibly to the point of non‐utility. As an initial exploration, this study will determine any change in die dependability of precipitation and average temperature forecasts downscaled to local and monthly time scales for several locations in Oklahoma. Dependability is a skill measure that assesses only those forecasts that are discernibly different from climatology. Downscaling to daily time scales is done in two steps, first to monthly forecasts, and then to generated ensembles of daily forecasts. This initial study will examine only the first step, the monthly downscaling. In order to assess the relative impact of downscaling in space versus time, forecasts will be downscaled separately in each, and then downscaled in both. Current forecast dependability for Oklahoma at the larger scales is limited compared to regions of the US that experience stronger ENSO impacts, so any degradation from downscaling to monthly forecasts and specific locations should be readily apparent.

Select this Article		Responding to Concerns about Flexibility in Agricultural Water Management in the Western U.S.: A Climate of Uncertainty John D. Wiener ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)41 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper for the Proceedings is due well before we will have results of workshops on problems which may arise from new forms of water transfer, so the paper describes the larger context and the new forms. These materials focus on Colorado, but applications are not limited to Colorado. The presentation will report on later progress; both will be available on a website to be established. The organization of the paper is (1): Abstract of the Presentation, (2) Changing Demands for Water — Additional Context, (3) Under‐represented Interests, (4) New Forms of Transfer Under Discussion, (5) Potential Benefits of Better Management: The Big Vision, and (6) Getting There. The desirability of increased flexibility in agricultural water management in the Western U.S. has been long established. The pressures of changing demands for water interact with very fast urban and peri‐urban population growth to threaten transfer of irrigation water away from rural areas and traditional uses with minimal benefit to the areas of origin, and with significant threat to environmental and recreational interests. In a thin, disorganized water market, transfers have been generally large, carried high adverse impacts, and been arranged in secretive fashion. Leasing, water banking, and other flexible management techniques have increased in recent years, partly in response to high interest in the preservation of agriculture and its landscapes. Improved flexibility in management includes increasing opportunity to respond to climate information. Work on barriers to use of climate information applications led to envisioning use of water transfers to create means for non‐market interests to enter water rights markets and to stimulate improvements in agriculture and rural viability. This paper includes a concise presentation of the author's formulation of three kinds of transfers needed, and principles important for water transfers.

Select this Article		Optimizing Management Efforts for Sustainable Long‐Range Water Supply Planning Viktoria Zoltay Titcomb, Paul H. Kirshen, and Richard M. Vogel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)42 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Complex watershed models with decision support systems (DSS) have been developed to aid in integrated water resources management (IWRM) and sustainable water supply planning. Detailed simulation models are important in determining operations policy but there is also a need for screening models that can compare a full range of management options before developing detailed site specific IWRM models. This study is an initial effort to develop a generic, optimization model and DSS that considers a comprehensive set of options for managing the quantity, quality, routing and use of water throughout the watershed including traditional water sources, direct and indirect water reuse, groundwater banking, demand management and land use management. The model is developed in accessible, familiar software with a user interface to facilitate the application of the model. A DSS is integrated in the interface to provide extensive output analysis to aid in recognizing and understanding relationships and tradeoffs, thereby supporting informed decision making.

Select this Article		Artificial Neural Network Approach for Streamflow Forecasting in India Using ENSO and EQUINOO Rajib Maity and D. Nagesh Kumar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)43 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract It is well recognized that hydrologic time series, like rainfall, streamflow etc. are modulated by various large‐scale atmospheric circulation patterns, like El Niño Southern Oscillation (ENSO) etc., throughout the globe by climatic teleconnection. Indian summer monsoon rainfall (ISMR) is proved to be significantly influenced by ENSO. Recently, it is established that relationship between ISMR and ENSO is modulated by the influence of atmospheric circulation pattern over Indian Ocean region, like, Equatorial Indian Ocean Oscillation (EQUINOO). Thus, for Indian subcontinent, hydrologic time series are significantly influenced by ENSO along with EQUINOO. Though influence of these large‐scale atmospheric circulations on rainfall is investigated, their influence on streamflow is yet to be investigated. In this paper, information of ENSO from tropical Pacific Ocean and EQUINOO from tropical Indian Ocean are used in terms of their corresponding indices for streamflow forecasting. To model the nonlinear, time‐varying and dynamic relationship between streamflow and such large‐scale atmospheric circulation information, Artificial Neural Network (ANN) methodology has been opted for the present study. Efficient optimization of ANN architecture is obtained by using evolutionary optimizer based on genetic algorithm. This study concludes that use of such large‐scale atmospheric circulation information potentially improves the performance of streamflow prediction which, in turn, helps in better management of water resources.

back to top

CLIMATE, METEOROLOGY, AND WATER RESOURCES III

Select this Article		Is Climate Change Evident in U.S. Streamflow? Ajay Kalra, Thomas C. Piechota, Rob Davies, and Glenn A. Tootle ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)44 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The study presented here focuses on the changes/trends in U.S. streamflow from 639 unimpaired stations for the period 1951 – 2002. This is particularly relevant since the issue of climate change is of interest to many and studies have also indicated an abrupt change in climate around the year 1976/77. Trends in U.S. streamflow were evaluated using three statistical tests: Spearman's Rho, Mann‐Kendall, and Linear Regression. Step changes in the streamflow data were evaluated using the Rank Sum and Student t test. The multiple tests provide robust results in which areas of the U.S. have experienced significant changes in streamflow data. The number of stations experiencing an increasing or decreasing trend/step change in any given water year were evaluated at a 95% confidence level. Results indicated that the Upper and Middle Mississippi River basin has an increasing trend in streamflow quantity. For the Pacific Northwest and some stations in Florida, the streamflow quantity is decreasing.

Select this Article		Support Vector Machine Approach to Downscale Precipitation in Climate Change Scenarios Shivam Tripathi, V. V. Srinivas, and Ravi S. Nanjundiah ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)45 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Concern over changes in global climate has increased in recent years with improvement in understanding of atmospheric dynamics and growth in evidence of climate link to long‐term variability in hydrologic records. Climate impact studies rely on climate change information at fine spatial resolution. Towards this, the past decade has witnessed significant progress in development of downscaling models to cascade the climate information provided by General Circulation Models (GCMs) at coarse spatial resolution to the scale relevant for hydrologic studies. While a plethora of downscaling models have been applied successfully to mid‐latitude regions, a few studies are available on tropical regions where the atmosphere is known to have more complex behavior. In this paper, a support vector machine (SVM) approach is proposed for statistical downscaling to interpret climate change signals provided by GCMs over tropical regions of India. Climate variables affecting spatio‐temporal variation of precipitation at each meteorological sub‐division of India are identified. Following this, cluster analysis is applied on climate data to identify the wet and dry seasons in each year. The data pertaining to climate variables and precipitation of each meteorological sub‐division is then used to develop SVM based downscaling model for each season. Subsequently, the SVM based downscaling model is applied to future climate predictions from the second generation Coupled Global Climate Model (CGCM2) to assess the impact of climate change on hydrological inputs to the meteorological sub‐divisions. The results obtained from the SVM downscaling model are then analyzed to assess the impact of climate change on precipitation over India.

back to top

3‐D FREE SURFACE FLOW MODELING AND COASTAL MODELING

Select this Article		Three Dimensional Numerical Modeling of Cohesive Sediment Transport in a Shallow Oxbow Lake Xiaobo Chao, Yafei Jia, F. Douglas Shields, Jr., and Charlie Cooper ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)46 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the development and application of a three‐dimensional numerical model for simulating the cohesive sediment transport in water bodies where both currents and wind‐driven waves are important. The model was verified by a simple test case with an analytical solution (nonconservative tracer in a prismatic channel with uniform flow) and applied to Deep Hollow Lake, a small oxbow lake in Leflore County, Mississippi. The model produced predictions within 2% of the analytical solution. The bottom shear stresses induced by currents and waves were calculated, and the processes of resuspension, deposition and settling were considered. The primary forces associated with sediment transport were caused by wind‐induced currents and waves. Simulated sediment concentrations were compared with limited field observations available, with generally good agreement. Simulated concentrations for a scenario with wind‐driven waves were about one to three times greater than for a simulation without wind‐wave processes.

Select this Article		Numerical Modeling of Morphological Processes around Coastal Structures Yan Ding, Yafei Jia, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)47 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Integrated numerical models are developed to simulate irregular wave deformations, wave‐induced currents, sediment transport, and morphodynamic changes around detached breakwaters in coasts. The models are capable of taking into account various wave deformations, e.g. diffraction, transmission through permeable structure, breaking, etc. The computed morphodynamic changes around a detached breakwater, including deposition/erosion behind the structure, local scours at tips of the structure, and bars in offshore, are in good agreement with the measurements.

Select this Article		Modeling Hydrodynamics and Storm Effect in the Altamaha River Sound Kijin Nam and Mustafa M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)48 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Altamaha River has the largest watershed among Georgia's rivers and the second largest one among the eastern United States. Despite its importance, die Altamaha River sound and its hydrodynamics are not studied extensively. This study is composed of two parts. In the first part we investigated hydrodynamics in the Altamaha River sound using a numerical model in order to understand the basic behavior of contaminant transport in this region. This numerical study is carried out using EFDC (Environmental Fluid Dynamics Code), which is a widely used 3‐D hydrodynamics and transport model. To simulate a realistic case, various data such as history of wind and river discharge is obtained and applied. Result shows that the tides are the major forcing factor in contaminant transport in the sound. A three‐dimensional structure of salinity, a salt wedge, is also observed to influence the transport process. The second part of this study deals with impacts of possible hurricanes in the region. A hypothetical long wave as a storm surge is assumed and its effects are simulated using the same techniques and tools used in the first part. No significant delay of wave is observed. The transport of contaminants released by this flooding is studied as well with drifting particles in the simulations. The movement of particles depends on where they are initially released and geographical configuration of the release point. Some particles settle on ground and others stay in bays several days before they are discharged into the ocean.

Select this Article		Numerical Modeling of Internal Flow Structure in Submerged Hydraulic Jumps John P. Raiford and Abdul A. Khan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)49 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This study compares experimental data taken from a submerged hydraulic jump to results from a k − ε and RNG numerical simulation. The internal flow structure of the jump is investigated by comparing longitudinal and vertical velocity profiles along a vertical direction as well as water surface profiles. The maximum turbulent kinetic energy and longitudinal velocity distribution along the length of the jump are also investigated. The characteristics of the recirculation eddy are investigated by locating the reverse flow in the longitudinal direction. Previous research done on hydraulic jumps has relied on assumptions about the turbulent flow field whereas in this study the turbulence is a part of the solution. The computational grid is based on the experimental set up. The CFD program FLOW‐3D was used to simulate the experimental conditions with k − ε and RNG turbulence closure schemes. The results showed that the RNG model performed better in the near bed regions. Also, mean flow conditions returned more quickly in the experiment than either model.

back to top

ADVANCES IN SIMULATION TECHNIQUES FOR HYDRAULIC STRUCTURES

Select this Article		Use of Computation Fluid Dynamic Modeling to Evaluate Pump Intake Performance and Develop Design Modifications Edward Wicklein, P.E. and Mizan Rashid, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)50 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The generating capacity of a power plant is being increased through the addition of another power block at the facility. The plant utilizes a once through cooling system with a large onsite pond for water storage. The new power block will require additional pumping capacity. A large intake structure containing eight 6.31 m³/s circulating water pump in separate bays is located on the pond. One proposed approach for supplying cooling water to the new power block was through the addition of six 3.15 m³/s pumps within the existing intake bays. This approach would reduce the construction schedule and the project cost. A commercial computation fluid dynamic (CFD) model was used to investigate the pump approach hydraulics, and evaluate the likelihood of traditional design modifications to improve the flow conditions approaching the pump intakes. Traditionally, physical hydraulic models have been used to evaluate pump intake design modifications. A CFD model was used for this study because it could demonstrate the feasibility of the project more quickly and at a lower cost than it would take for performing a physical model study. Results from the CFD model demonstrated that traditional intake design modifications could improve the intake hydraulics.

Select this Article		Numerical Modeling of Culvert Hydraulics: Modernization of Existing HY8 Software Brian. J. Rowley, Elizabeth A. Thiele, Rollin H. Hotchkiss, Ph.D., P.E., and E. James Nelson, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)51 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Several software programs have been developed to assist in the hydraulic design and analysis of culverts. Of the available programs, HY8 is the most widely used and distributed. The first version of HY8 was provided by the Federal Highway Administration (FHWA) for distribution in the 1980s. Since that time, understanding of culvert hydraulics has increased significantly and acceptable modeling techniques have been further developed. Computer capabilities have also advanced to facilitate better graphical displays and post processing options. As a result, modernization of HY8 is timely. This paper will provide a brief overview of the existing HY8 software in order to understand its capabilities and limitations. Further, the need for and status of an updated version of HY8 will be presented, including a comparison of the old and new HY8 interfaces.

Select this Article		Applied Mathematical Model for Turbulent Boundary Layers Junke Guo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)52 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We present a complete analytical model for mean velocity profile in turbulent boundary layers. The model integrates the conventional log‐wake law and the Barenblatt power (scaling) law in the intermediate region so that it includes the effects of the Reynolds number. Furthermore, it includes the effects of the wall and the boundary layer edge so that the model can describe the entire turbulent boundary layer mean velocity profile analytically. The model has been confirmed with recent laboratory experimental data of Osterlund.

back to top

APPLIED COMPUTATIONAL HYDRAULICS TO MEET ENVIRONMENTAL CHALLENGES

Select this Article		A 3D CFD Model Investigation of an Outfall Reservoir Hydraulics for Repowering a Power Plant Liaqat A. Khan, Edward A. Wicklein, and Mizan Rashid ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)53 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A three‐dimensional (3D) computational fluid dynamics (CFD) model of an outfall system, discharging cooling water to a reservoir through an existing outfall structure and a proposed diffuser, is presented in this paper. A repowering of the plant would increase the discharge from 55 m³/s to 76.5 m³/s. The CFD model used for the study consisted of over 1.3 million computational cells, with grid spacing varying from 0.05 m to 2.5 m. For the existing conditions, the model results indicated that a high velocity jet from the outfall structure was deflected southward and the jet impinged the southern embankment. To minimize potential erosion, the ports of the diffuser were designed to discharge water towards the water surface with a northward velocity component. With such a diffuser, model simulations indicated a significant reduction in velocities near the southern embankment. The 40 percent increase in the outfall discharge did not significantly increase the maximum near bed velocities in the reservoir.

Select this Article		Mathematical Modeling of Fate and Transport of Dissolved and Particulate Mercury in Riverine Systems Arash Massoudieh, Fabian A. Bombardelli, and Timothy R. Ginn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)54 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Mercury is a hazardous metal in the environment that in many cases is concentrated in riverine and estuarine bed sediments, from which mercury can be mobilized due to erosion of the top layer. In this research, a one‐dimensional flow and transport sub‐model representing the transport of mercury in the river is coupled with several one‐dimensional sub‐models incorporating diffusive transport, transformation and sorption of mercury species in the bed sediments. Transport of dissolved and particle‐associated mercury in the water, and thus the effect of erosion and resuspension of particles on the transport process, is taken into consideration. A set of one‐dimensional reactive transport sub‐models are utilized to represent the release, adsorption, and burial of mercury species to the bed sediments. This transport model is coupled with a detailed biochemical reaction network that includes main mercury species as well as major components which are effective in production of Methyl‐Mercury. The goal of this coupling is to quantify methylmercury production using basic principles. Model parameters are obtained using available literature data and by calibration of the one dimensional‐reactive transport model to available column and batch study data. The model can be used for simulating transport of mercury and production of methylmercury, examining various remediation scenarios, and evaluating the effect of anthropogenic activities on resuspension or burial of mercury species in water systems after doing appropriate calibrations.

Select this Article		Comprehensive Flow Analysis and Near‐Realtime Based Streamgauging Planning at Water Control Structures Tibebe Dessalegne, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)55 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract South Florida Water Management District (SFWMD) manages man‐made and natural systems including the Kissimmee River, Lake Okeechobee, constructed wetlands and the Everglades. Water within this complex hydrologic system is conveyed through a network of canals and controlled by over 200 major and 2000 smaller hydraulic structures (i.e., gated culverts, gated spillways and weirs) and about 25 pumping stations. Accurate estimate of the quantity of water passing from one component of the system to the other is inevitably vital for water resources planners as well as decision makers in meeting the SFWMD's main goals including flood protection, environmental restoration and water supply. As a result of this, the SFWMD continuously monitors water levels and operation settings (gate openings and pump engine speeds) at water control structures and subsequently computes flow employing appropriate flow equations derived from governing hydraulic principles. These flow equations, however, need to be calibrated in an attempt to generate optimal values of flow equation parameters that minimize the error between computed and measured flow. For successful calibration of flow equations, however, measurements need to spread over the entire range of operation settings of the hydraulic structures and should cover all possible flow types. Planning streamgauging to minimize data redundancy and in turn cut monitoring cost entails extracting near‐realtime water levels (head water and tail water) and operation conditions, identifying data gaps and determining the suitability of current conditions for taking measurements. In order to automate the flow analysis and streamgauging planning processes, a comprehensive computer tool is developed by integrating flow computation and data gap identification algorithms with flow measurement, near‐realtime, and structure information databases. The developed tool including a graphical user interface has the capability to calibrate flow ratings, compute flow, summarize flow types, visualize flow parameters, depict current flow condition and identify streamgauging opportunities. The developed tool was tested on hydraulic structures including pumps, gated spillways, and gated culverts. It has subsequently applied in planning regular streamgauging as well as emergency streamgauging during the hurricane season.

Select this Article		Use of EPA SWMM5 for Generation of BMP Effluent EMC Distribution Wayne C. Huber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)56 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Simulation of best management practice (BMP) and low‐impact development (LID) effects on stormwater quality is discussed with reference to the EPA Storm Water Management Model (SWMM), version 5. Many such treatment facilities demonstrate a lognormal distribution of effluent event mean concentrations (EMCs). Methods for use of SWMM5 to produce simulated EMCs with similar frequency characteristics are discussed in this paper. Model output was not available at the time of preparation of this paper and will be shown when the paper is presented.

back to top

FLOW AND MASS EXCHANGE PROCESSES AROUND HYUDRAULIC STRUCTURES USING EDDY RESOLVING NUMERICAL MODELS

Select this Article		Analysis of Mechanisms of Contaminant Removal from a Bottom River Cavity Kyoungsik Chang, George Constantinescu, and Seung‐O Park ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)57 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The mechanisms responsible for contaminant removal from a bottom rectangular cavity in a channel are investigated using fully three‐dimensional (3D) Large Eddy Simulation (LES) simulations. The aspect ratio (length/depth) of the 2D cavity is L/D=2 and the neutrally buoyant contaminant (passive scalar) is introduced instantaneously inside the cavity once the flow has developed. The flow upstream the cavity is fully turbulent. The large scale coherent structures in the shear layer region induce large scale pressure fluctuations at the trailing cavity edge and convection of patches of vorticity inside the cavity, parallel to the trailing edge. These patches modulate the intensity of the jet like flow that develops along the trailing edge and bottom cavity walls. It is shown that the eddies convected from upstream of the cavity can play an important role in accelerating the extraction of contaminant from inside the cavity. It is found that the contaminant ejection can be described using simple 1D dead‐zone theory models in which a single‐valued global mass exchange coefficient can be used to describe the contaminant mass decay inside the cavity over the whole extent of the ejection process.

Select this Article		Investigation of Flow Around a Bridge Abutment in a Flat Bed Channel Using Large Eddy Simulation Mete Koken and George Constantinescu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)58 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Large Eddy Simulation (LES) is used to numerically investigate the horseshoe vortex (HV) system around a vertical bridge abutment located on a flat bed in a straight channel with vertical lateral walls corresponding to conditions at the initiation of the scour process. The simulation is performed with upstream fully turbulent flow including the turbulent fluctuations obtained from a precalculated LES simulation. The dynamics of the instantaneous coherent structures associated with the HV system around the base of the abutment and the spectral content of the flow in this region are analyzed. Due to the flat bed conditions, for which the HV system is not stabilized by the presence of the scour hole, very large random variations in the structure, position, size and overall intensity of the turbulent HV system are observed. In particular, the HV system appears to oscillate between a zero‐flow mode in which the main HV is situated closer to the abutment and the near‐bed jet flow beneath it is weak and separates early, and a back‐flow mode in which the near‐bed jet flow is stronger and separates at a larger distance from the abutment, and the main HV eddy is larger. It is observed that the legs of the horseshoe vortices can interact, at times, with the eddies shed inside the detached shear layer (DSL). The distribution of the bed shear stress shows that the largest values are present in the strong acceleration region near the tip of the abutment, but high bed shear stress values are observed beneath the HV system. It is found that the bed shear stress fluctuations around the local mean values can be very high, especially in the region beneath the separated shear layer. The pressure fluctuations and resolved kinetic energy levels are found to be very high inside the HV region compared to the surrounding flow. These high values are produced primarily by the low‐frequency chaotic switching of the HV system between the zero‐flow mode and the back‐flow mode.

back to top

MODELING MORPHODYNAMIC PROCESSES WITH HYDRODYNAMIC AND SEDIMENT TRANSPORT MODELS I

Select this Article		Numerical Simulation of Local Scour with Free Surface and Automatic Mesh Deformation Xiaofeng Liu and Marcelo H. Garciá ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)59 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A numerical model for local scour with free surface and automatic mesh deformation is constructed and numerical simulation is carried out to compare with experimental results. The kappa‐epsilon model is used to simulate the turbulent flow field. Two interfaces (water and air, water and sediment) in the domain are captured with different approaches. The free surface of the flow is captured by Volume of Fluid (VOF) scheme which is a Eulerian approach. The water‐sediment interface (bed) is captured with moving mesh method which is a Lagrangian approach. The flow field is coupled with sediment transport using a quasi‐steady approach. Good results have been obtained using current model. The flow field is comparable with the experiment. Scour patterns are similar to the experimental data.

Select this Article		Numerical Simulation of the Morphodynamics in Rills J. Sanford and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)60 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this research project was to develop a 1‐dimensional hydrodynamic/ sediment transport model to simulate flows and sediment transport in rills. The present paper focuses on only the hydrodynamic component of this research. There are many challenging issues that need to be addressed regarding flow in rills. The most important issue is that flow under certain conditions can become transcritical. In this case, step and pool sequences become ubiquitous features of the geomorphology of a rill. In order to address this issue an enhanced TVD‐MacCormack scheme was employed. The sensitivity and validity of the code, named 3ST1D (steep stream sediment transport 1‐D), was tested for two cases. Because the emphasis here was on the hydrodynamic component of the model, the bed was fixed for the two test case scenario considered here. The model results satisfied the continuity equation for the stream reaches considered and provided and adequate mapping of the water surface profile and the depth averaged velocities.

Select this Article		Modeling Sediment‐Laden Gravity Currents Xinya Ying ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)61 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The gravity currents formed by instantaneous releases of a fixed volume of a suspension of fine sediment into a rectangular channel filled with tap water are studied numerically. The numerical model based on the filtered Navier‐Stokes equations and mass transport equation is used to model dynamics of the flow and sediment transport. The effects of subgrid eddies on flow and sediment transport were calculated based on the modified Smagorinsky model that takes into account the effect of buoyancy on turbulence. The sediment transport is computed by the dispersion model. The governing equations are solved based on the operator‐splitting algorithm and the third‐order CCS scheme, which employs the Crank‐Nicolson scheme for time advancing and the cubic spline to fit the spatial distributions of physical variables such as velocity components and concentration. Such a numerical scheme has been proven stable and almost free of numerical diffusion. The paper presents the comparisons between the numerical results and the experimental data such as propagation speed and areal sediment deposit. It is found that the numerical model is capable of correctly reproducing the flows and the associated sediment transport processes.

Select this Article		A Staggered‐Grid Scheme for the Advection‐Dispersion Equation Chuanjian Man and Christina W. Tsai, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)62 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A higher‐order accurate numerical scheme is developed to solve the advection‐dispersion equation. A staggered‐grid system is introduced with the first‐order spatial derivatives being approximated by the fourth‐order accurate finite‐difference scheme, thus keeping all truncation errors to a smaller order of magnitude than that of the dispersion term. The dispersion term, a second‐order spatial derivative, is discretized by the second‐order accurate finite‐difference scheme. For the time derivative, the fourth‐order accurate Adams predictor‐corrector method is used. The numerical method is validated against available analytical solutions for a one‐dimensional problem. The stability analysis is carried out using the Van Neumann method. It is shown that the proposed algorithm has a good stability property and there is no need to add a numerical dispersion term. As a result, the model can provide more accurate and stable results for long‐term simulation. The model is demonstrated to be a useful and accurate modeling tool for a wide range of transport problems.

back to top

MODELING MORPHODYNAMIC PROCESSES WITH HYDRODYNAMIC AND SEDIMENT TRANSPORT MODELS II

Select this Article		Modeling Channel Morphologic Change in the West Jordan River, Utah Dong Chen and Jennifer G. Duan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)63 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Many existing river morphological models are limited by their inability to account for erodible banks. In this study, the sediment continuity equation was solved to determine the rate of bed degradation and aggradation. The rate of bank erosion was calculated by determining bed degradation, lateral erosion, and bank failure. To be applicable to the West Jordan River, two layers in the bank surface were considered herein. This bank erosion mode distinguishes itself from other models by relating bank erosion rate with not only flow but also sediment transport near the bank. Additionally, bank height, slope, vegetation, and thickness of each layer in the bank surface were considered. For the purpose of long‐term simulation, decoupling technique is used among the flow, sediment transport, and bank erosion models. Furthermore, a new technique of computational mesh adjustment was also put forward. The developed model was then applied to simulate the processes of meandering migration in the study reach from 1981 to 1992. The reasonable agreements between simulated results and the available observations indicate the capability of this model in simulating channel morphologic change in the West Jordan River, Utah.

Select this Article		Numerical Simulation of Meandering Evolution Jennifer G. Duan, Ph.D., P.E. and Pierre Julien, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)64 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Evolution of meandering channels, a complex morpho‐dynamic process, has been the focus of research challenging geomorphologists and river engineers for decades. The evolution of meandering channel is a result of the complex interactions between flow, sediment transport, and bank erosion. A numerical model including a depth‐averaged two‐dimensional hydrodynamic flow model, a sediment transport model, and a bank erosion model was developed to simulate the evolution of a low sinuous meandering channel into a high sinuous one. The sediment transport model calculates both bed load and suspended load assuming equilibrium sediment transport. Bank erosion simulation consists of two interactive processes: basal erosion and bank failure. The mass conservation equation where sediment from basal erosion and bank failure is considered as a source term, was solved to obtain the rate of bank erosion. Then, this model was applied to simulate the evolution of free meandering channels in laboratory experimental settings. The model successfully replicated the evolution processes of meandering channel from downstream translation, lateral extension, and then follows by upstream and downstream rotation when sinuosity approaches 3.7. Plots of meandering planforms illustrate the capabilities of numerical model in simulating the evolutions of meandering planform (e.g. downstream translation, lateral extension, upstream and downstream rotation).

Select this Article		Three‐Dimensional Mean Flow and Turbulence around a Spur Dike Jennifer G. Duan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)65 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an experimental study conducted at the St. Anthony Falls Laboratory, University of Minnesota. Flow field at the neighborhood of a spur dike was measured by using a SonTek 10 MHz Acoustic Doppler Velocimeter (ADV). Time‐history of velocities in all three spatial dimensions was recorded at 650 nodes near the dike. The time‐averaged mean velocity and Reynolds stresses were calculated from the measurements. The results showed two counter‐rotating secondary flow cells formed immediately downstream of the dike. The secondary flow cell at one side of the channel having the dike grows gradually, while the other cell decades until separated flows rejoin. These measurements clearly demonstrated the spatial distributions of turbulent normal stresses and Reynolds stresses. Additionally, bed shear stresses were calculated by using mean flow and turbulence Reynolds stresses. Bed shear stresses calculated by using Reynolds' stresses are more accurate for approximating bed shear stresses field around the dike.

Select this Article		Prediction of Equilibrium Flow and Bed Load Transport in a Curved Bend Jie Zeng, George Constantinescu, and Larry Weber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)66 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A recently developed fully non‐hydrostatic model to predict flow, sediment transport and equilibrium bathymetry using RANS models without wall functions and with capabilities to account for bed roughness effects is used to predict the equilibrium flow and sediment transport in a 140° curved channel bend studied experimentally by Struiksma under incoming steady‐flow conditions. Additionally, a bed load transport module based on Engelund and Hansen total bed load formula is implemented and tested. In the experiment, the bed load was observed to be dominant, so the suspended sediment component is considered negligible in the simulations. The streamwise variation of the relative water depths at several representative sections are compared with the experimental data. It is found that the best agreement is obtained when the total load (which in the test case considered is equal to the bed load) is estimated using Engelund and Hansen formula with both k‐ω and Spalart‐Allmaras models. The k‐ω predictions, using the originally implemented non‐equilibrium bed load transport model based on van Rijn and Wu et al. methodology, are found to overpredict the water depths in the first half of the bend. The main reason for the underperformance of the van Rijn model is its inability to predict the experimentally measured bed load in the initial straight part of the channel.

back to top

MODELING OF DAM‐BREAK AND LEVEE‐BREACH FLOWS OVER FIXED AND MOVABLE BEDS

Select this Article		1‐D Numerical Simulation of Morphodynamic Processes under Dam Break and Overtopping Flows Weiming Wu and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)67 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A 1‐D finite‐volume model has been established to simulate the morphodynamic processes under dam‐break and overtopping flows over movable beds. The effects of sediment transport and bed change on the flow are considered in the flow continuity and momentum equations. An explicit algorithm is adopted to solve the governing equations. The model has been tested against an experiment on dam surface erosion due to overtopping flow and two experiments on dam‐break flow over movable beds. The model performs quite well in the case of overtopping flow, but significantly under‐predicts the bed erosion due to dam‐break flow. A modification has thus been made by considering the effects of sediment concentration on sediment settling and entrainment. The modified model predicts the bed erosion under dam‐break flow with much improved accuracy.

Select this Article		Two‐Dimensional Flood Simulation on Unstructured Grids Xinya Ying, Jeff Jorgeson, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)68 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A two‐dimensional flood simulation model using unstructured grids has been developed to study the hydrodynamics of flooding processes. The model employs the finite volume method to solve the conservative form of the shallow water equations. The HLL approximate Riemann solver is used for computing the intercell fluxes because of its robustness and easiness to implement. The momentum equation used in the model has only one source term representing the driving forces, so that numerical imbalance between source and flux terms can be easily eliminated. In addition to the model formulation, this paper presents the model verifications and validations against analytical solutions and experimental data for a partial dam‐break problem and an oblique hydraulic jump test case, respectively. The results show that the model can correctly account for the two‐dimensional shallow water flows which may have mixed flow regimes and dry bed problems. These features can allow the model to simulate complicated real‐life flooding problems.

back to top

MODELING OF DAM-BREAK AND LEVEE-BREACH FLOWS OVER FIXED AND MOVABLE BEDS

Select this Article		Dam Break Hydraulics in Natural Rivers Arup Kumar Sarma and Mimi Das Saikia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)69 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An investigation is carried out for numerical computations of dam break hydraulics in Natural Rivers with Explicit Finite Difference (EFD) Schemes. Although computational Dam Break Hydraulics is a topic of interest over more than 100 years, numerical simulations of dam break flow in relatively simple channels are found more often compared to real river flood simulations. Natural River channel with wide floodplains make the computation cumbersome as Natural River channels are highly non-prismatic with significant variations in River bed slope and friction. In this study, first order Diffusive Scheme, second order modified two-step Predictor Corrector scheme and Total Variations Diminishing (TVD) McCormack Predictor Corrector using Venn Leer Flux limiter are analyzed by solving unsteady flow equations in conservative and non conservative forms for simulating a hypothetical dam break situation in a Himalayan River in India. The height of the dam is 245 metres. Upstream length of the channel is 40,000 m and downstream is 64,000 m, the elevation of the bed of the channel changes from 545 m to 126.95 m, change in the channel width ranges from 300 m to 5650 m and Manning's roughness coefficient varies from 0.03 to 0.035 depending on the channel characteristic. The numerical solutions of the EFD are relatively tested for their performances giving special emphasis to some parameters such as the flood depth at different sections and inundated area at different time periods after the failure of the dam and travel time of the flood waves; which are most important for the practicing engineers for efficient flood management. The computational aspects of the numerical models i.e. the implementation efforts of the schemes, run time required are compared. The applicability of the complex numerical corrections such as TVD in the numerical model for refinement in the solutions of dam break hydraulics in Natural Rivers is also examined. The stability and accuracy of the numerical solutions for both conservative and non conservative formulations are analyzed, and it is observed that numerical simulation of flows for complex real River topography in conservative forms with simple EFD schemes are advantageous from practical point of view compared to the higher order Explicit or Implicit Finite Difference or Finite Element schemes which increase the run time significantly and make the implementation complex.

back to top

MODELING OF DAM‐BREAK AND LEVEE‐BREACH FLOWS OVER FIXED AND MOVABLE BEDS

Select this Article		Numerical Dynamic Analysis of Sonnateh Dam Body Located on an Active Fault H. Abbasi, Y. Hosseini Asli, and H. Jalaly ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)70 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The design of dam body for an earthfill dam is the most important analysis in dam study. The Sonnateh dam is located on an active fault with measured deflections. The dam body analyses are performed based on two methods in order to reach a suitable slope for upstream and downstream of dam body. The upstream and downstream slope of dam body is calculated based on optimal analyses of dam body in different load conditions with linear and nonlinear determination. The two dimensional analysis of dam body with MCL and MDL is performed by GEO‐SLOPE program. This analysis was a preliminary determination of dam body dimensions. The amount of safety factor and steady displacement of dam body is calculated during the earthquake. Also, the three dimensional analysis of fault movement is performed using ANSYS finite element based program. This analysis indicated the displacement of dam body which has to compare with allowable displacement of clay core. Based on this analysis, the safety factor of dam body is determined.

back to top

NUMERICAL MODELING AS A TOOL IN WETLAND RESTORATION

Select this Article		Application of Multi‐Criteria Tool in MIKE SHE Model Development and Testing M. H. Rubarenzya, A. M. ASCE, P. Willems, J. Berlamont, and J. Feyen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)71 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The water resources in the northern part of Belgium have been profoundly influenced by anthropogenic activities. Physical deterioration of rivers and their floodplains is common. In general, hydrometeorological disasters have grown to be the most significant natural disaster in terms of frequency, but also in terms of costs to human life and property damage. River valley rewetting is believed to influence the ecology positively, especially during the dry summer months. However, its hydrological influence on the catchment over the annual cycle remains unclear, especially with regard to the winter months. Thus, this research undertook to build an integrated catchment model for a part of northern Belgium in order to study the hydrological influence of rewetting. The paper details the development and testing processes of the model. It highlights the design of a multi‐criteria protocol that was used to develop and test the model, the process of determining recession constants corresponding to base flow, interflow, and overland flow components, and the paradox of homoscedascity. It describes WETSPRO, which is a tool for time series analysis which incorporates a recursive digital filter for exponential recessions to split total rainfall‐runoff discharges into three components namely, base flow, interflow, and overland flow. The paper presents the results of an implementation of WETSPRO in multi‐criteria model development and testing, during which the following plots were utilized: Modeled vs. observed discharge maxima during (nearly independent) quick‐flow hydrograph periods; Modeled vs. observed discharge minima during (nearly independent) base‐flow or slow‐flow hydrograph periods; Cumulative flow volumes; High flow extreme value statistics; Low flow extreme value statistics; and Discharge time series, with and without log‐scale for the discharge. Using the multi‐criteria protocol, a hydrological model was built. The flow recession constants were determined as approx. 12 hours for quick flow, and 2 months for slow flow. This model is being used to study the effects of anthropogenic changes on the catchment hydrology.

Select this Article		The Use of Numerical Models for the Buena Vista Lagoon Restoration Feasibility Analyses Ying Poon, Sc.D., P.E. and Sherilyn Kimura, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)72 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A feasibility study was conducted for wetland restoration alternatives for the Buena Vista Lagoon Restoration Feasibility Study with three different hydrologic regimes — fresh water, salt water, and mixed water (combination of fresh and salt water). The alternatives were evaluated based on flood impacts, maintenance dredging requirements, and habitat distribution. A modeling approach was developed to help compare the three alternatives with the existing condition. Evaluation of each alternative was further complicated due to the different physical processes occurring within each alternative. Physical processes evaluated include watershed loadings (e.g., fresh water flows, fluvial sediments, and nutrient loadings), lagoon hydrodynamics, lagoon salinity, lagoon sedimentation, as well as coastal processes (e.g., tidal inlet/outlet stability and littoral sedimentation) for salt and mixed water configurations. Quantifications of these processes were conducted using a combination of numerical models and analytical methods enabling the linkages of multiple processes.

Select this Article		Water Budget and Hydrodynamic Modeling of the A.R.M. Loxahatchee Refuge Ehab A. Meselhe, Michael G. Waldon, Alonso G. Griborio, Jeanne C. Arceneaux, and Emad Habib ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)73 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Arthur R. Marshall Loxahatchee National Wildlife Refuge is the only remnant of the northern Everglades in Palm Beach County, Florida (USFWS, 2000). It includes 143,238 acres (58,000 ha) and is located seven miles west of the city of Boynton Beach. The U.S. Fish and Wildlife Service (USFWS) has indicated that changes in water quantity, timing and quality are introducing negative impacts to the Loxahatchee Refuge's ecosystem. According to the USFWS (2000) changes in hydroperiod and water depths' pattern affect wading birds feeding pattern, apple snail reproductive output, and alligator nesting, and also alter the distribution of aquatic vegetation and tree islands. In addition, high nutrient runoff causes proliferation of cattails, and other undesirable species that negatively affect the ecosystem's balance. It is a priority for the Loxahatchee Refuge to ensure an appropriate water regulation schedule that will produce maximum benefits for flood control, water supply, fish and wildlife; and also to better understand and minimize the impacts of the excessive nutrients' loading. This study presents the development of water budget and hydrodynamic models that are being used to provide a quantitative framework for management decisions related to inflow and outflow quantities, timing, and quality. The water budget model was developed as a double‐box model that predicts canal and marsh stages. This model was calibrated for the 5‐year period of record between January 1995 and December 1999, and validated with data for the 5‐year period of record between January 2000 and December 2004. Statistical analyses demonstrate the applicability of this model to predict temporal variation of water levels in both the marsh and the Refuge rim canal. A two‐dimensional hydrodynamic model was set up for the Refuge using the unstructured finite volume model FVCOM. This model is being used to predict spatial and temporal distribution of water inside the Refuge, and the results show very good agreement between observed and predicted stages at specific locations. Efforts are underway to model the transport of conservative tracer and the dynamics of total phosphorus in the Refuge.

Select this Article		Habitat Creation in Tidal Zones: Hydrologic Issues in West Coast Applications K. H. Price, P.E. and M. Martz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)74 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The creation of effective tidal marsh habitat can be streamlined using hydraulic design tools as well as through the proper identification of applicable reference sites. The frequency of inundation corresponding to vegetation zones observed at reference sites can be used to design the elevation zones of proposed tidal marshes. Seasonal fluctuations in salinity levels can affect the suitability of vegetation types in tidal zones. Project success also depends to a large extent on protection from wave action. This paper discusses issues encountered in designing habitat enhancement projects in tidal zones, including analysis of historical tidal records, application of various hydraulic modeling tools, identification of applicable reference sites, establishment of desired elevation zones for plant communities, and accounting for water quality fluctuations arising from freshet conditions. Tidal marsh habitat may be desired in areas previously outside of elevation zones suitable for vegetation establishment. In these cases, the configuration of the inlet channels and project site topography must account for the proper balance of sediment transport through tidal energy and freshwater inflow from landward sources in order to ensure a lasting project life with minimal maintenance.

back to top

NUMERICAL MODELING OF FLOW AND TRANSPORT PROCESSES AT HYDRAULIC DAMS AND FISH PASSAGE HYDRAULIC STRUCTURES

Select this Article		Three‐Dimensional Hydrodynamic Simulation of Flows for Fish Passage at the Dalles Dam Songheng Li, Larry J. Weber, and George Constantinescu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)75 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Dalles Dam is located at river Mile 192 on the Columbia River, USA. Fish passage is considered one of the important operational functions for the hydropower dams on the Columbia River. The U.S. Army Corps of Engineers, Portland District (CENWP) and the Regional Resource Agencies (Region) have been evaluating fish passage concepts to protect downstream migrating juvenile salmonids at The Dalles Dam. To assist in this evaluation, a three‐dimensional (3D) computational fluid dynamics (CFD) model, developed at IIHR‐Hydroscience & Engineering, was selected to conduct CFD simulations, providing hydrodynamic flow information for fish passage efficiency assessment. The CFD model solves the Reynolds Averaged Navier‐Stokes (RANS) equations closed with the standard k‐ε model with wall function. The Dalles Dam forebay CFD model covers approximately 2,134 m from the spillway face to its upstream boundary. GRIDGEN of Pointwise®, Inc. was used to generate the 3D multi‐block structured meshes. The model was validated using the ADCP stationary target field data, and then applied to prediction of scenarios corresponding to flow conditions which occurred during 2002 to 2004, referred as FY02, FY03, and FY04.

Select this Article		Numerical Modeling Study for Fish Screen at River Intake Channel Jungseok Ho, Leslie Hanna, Brent Mefford, and Julie Coonrod ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)76 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A numerical modeling study of hydraulic performances of an angled vertical fish screen at a river diversion intake channel that was developed using a porous media numerical scheme. Flow patterns in the intake channel induced by the fish screen were computed with a three‐dimensional fluid dynamics computation program solving the Reynolds‐averaged Navier‐Stokes equations. Screen flow head loss coefficient were simulated and compared with the physical model values converted from the test measurements for the porous media numerical scheme applicability test. For validation of the numerical model, fish screen velocity ratio profiles of sweeping and approach were compared with physical model measurements. Different types of screen face material and baffle installations for uniform approach flow distributions were simulated. The numerical model shows very good agreement with the velocity ratio measurements, and modeling capability for different screen material types and baffle installations by controlling of the numerical model of the porous opening directions and adjustment of baffle porosities respectively.

Select this Article		A Three‐Dimensional Thermal Model for McNary Dam Marcela Politano, Md. M. Haque, George S. Constantinescu, and Larry Weber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)77 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water temperature is an important water quality parameter in aquatic ecosystems, impacting dissolved oxygen, chemical and biological reaction rates, and plant and animal mortality. In particular, during summer months, high temperatures in the forebay, gatewells and juvenile fish collection channel at McNary Dam lead to increased stress on fish population. A 3D hydrodynamic and heat transport model was developed to predict the water temperature on McNary Dam. The flow field was solved using an incompressible RANS solver for buoyant flows. The Boussinesq approach and a standard kappa‐epsilon model with wall functions were employed. The thermal model takes into account the energy sources due to solar radiation and the convective heat transfer at the free surface, which is function of the air temperature and wind velocity. The equations of the proposed thermal model were implemented into the commercial code FLUENT. The unsteady energy sources, boundary conditions at the free surface and inflows were programmed. A calibration for a typical day was conducted using measured temperature profiles and weather conditions. Comparison shows that the model reproduced general observed trends and daily fluctuations. The multidimensional temperature and velocities fields are presented and discussed.

back to top

ENVIRONMENTAL AND WATER RESEARCH OPPORTUNITIES

Select this Article		Drinking Water Research Funding Opportunities—the Awwa Research Foundation Elizabeth Kawczynski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)78 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Awwa Research Foundation (AwwaRF) is a member‐supported, international, nonprofit organization that sponsors research to enable water utilities, public health agencies, and other professionals to provide safe and affordable drinking water to consumers. Mission: Advancing the science of water to improve the quality of life. AwwaRF works to achieve the mission in three ways: By sponsoring research. AwwaRF sponsors an anticipatory and scientifically credible research program that is responsive to the needs of the water supply community. By developing knowledge. AwwaRF identifies the practical benefits of research findings and delivers this knowledge to stakeholders throughout the water supply community. By promoting collaboration. AwwaRF cultivates partnerships with organizations around the world to leverage funding and share expertise. The Awwa Research Foundation was established in 1966 to provide a centralized, practical research program for the drinking water community. Its research program, which is highly respected as being one of the most scientifically credible and best‐coordinated in the world, focuses on four main goal areas: (1) High‐quality water, (2) Efficient and customer‐responsive organization, (3) Infrastructure reliability, and (4) Environmental leadership. Specific research projects focus on the following: (1) Treatment Technologies, (2) Distribution System Operations, (3) Water Resources, (4) Water Quality, (5) Infrastructure, (6) Management, and (7) Health Effects.

back to top

TECHNOLOGY TRANSFER

Select this Article		Stormwater Pollution Prevention Education Effectiveness John A. Chapman, P.E., M. ASCE and Mikael Isensee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)79 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract National Pollution Discharge Elimination System Phase II construction and Municipal Separate Storm Sewer Systems permits have resulted in the need for education programs. These education programs have many challenges in regards to content, reaching adult audiences, and effectiveness. This paper presents the different ways the University of Minnesota Erosion and Sediment Control Certification Program is evaluating the effectiveness of its storm water pollution prevention education program. Included in this paper are general descriptions of the course structure, audiences, and use of partnerships with other agencies and organizations. Evaluating the effectiveness of reaching the correct audience, getting the information to the class attendees, helping the class attendees retain the information, and increasing compliance with stormwater pollution regulations are all key components of an educational program. Each of these aspects is measured through different means and requires different degrees of effort. The University of Minnesota Erosion and Sediment Control program has attempted to evaluate these components through surveys, testing, and comparisons to compliance records. The attendee surveys, pre‐testing, and post‐testing have provided helpful information for improving the program and classes. Evaluation of compliance inspections and comparison to training records of construction personnel has possibly provided some insight to the effectiveness of training on regulatory compliance. Of more importance is the understanding of how inspection data collection could be adjusted to provide additional value and more insight to the effectiveness of training on regulatory compliance.

Select this Article		An Overview of U.S. EPA and USDA Drinking Water Treatment System Demonstrations in China Craig L. Patterson, Lucille M. Garner, Roy C. Haught, and James A. Goodrich ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)80 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Under an interagency agreement with the U.S. Department of Agriculture, U.S. EPA has coordinated support for several water treatment research demonstrations in China. EPA has demonstrated several treatment technologies to improve water quality in small communities and has installed an immersed membrane water reuse system for a small brewery in China. U.S. EPA has also provided a water quality monitoring buoy and an automated weather station for monitoring of flood conditions (rainfall events) in a remote watershed. The weather station has been designed and built with a remote telemetry system to collect and submit real‐time data on an hourly basis. This presentation will focus on interagency cooperation and cooperation between the U.S. and China during implementation and completion of these drinking water demonstrations.

back to top

UNDERGRADUATE EDUCATION

Select this Article		Implementation of an On‐Line Asynchronous Tools to Facilitate Problem‐Based Learning in Water Resources Engineering Arthur Schmidt, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)81 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Student feedback from past semesters for the courses Water Resources Engineering and Urban Hydrology and Hydraulics has indicated that out‐of‐class guidance or coaching from the instructor in solving problems related to the course content was the most effective tool for learning the material from these courses. However, this proved to be an inefficient teaching tool. While similar guidance was commonly repeated to different groups of students, because the student groups progressed through problems at different rates and often all students could not schedule simultaneous time with the instructor. Furthermore, out‐of‐class coaching is also an inefficient learning tool because the instructor often is not available at the times when the students are working on the problems. The tools described in this paper addressed these inefficiencies by providing asynchronous access to help and guidance on the difficulties that the students commonly encounter while working on out‐of‐class problems for these courses. The three tools that will be discussed are: (1) a bulletin board that allows students to respond to each other's queries and to see the instructor's responses to the posted queries, (2) a set of daily on‐line quizzes that provide feedback and suggestions to the student about their individual results and provide feedback to the instructor about problem areas, and (3) an on‐line, help library providing coaching for the most frequently asked questions. This library contains video clips of actual help sessions, and links to additional help tools. These additional tools include animations illustrating the calculations and procedures, reference materials, and solved example problems.

Select this Article		A Video Production for Undergraduate Recruitment and Retention John W. Nicklow, Lizette R. Chevalier, Bill T. Ray, and Lilly A. Boruszkowski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)82 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Departments of Civil and Environmental Engineering and Cinema and Photography at Southern Illinois University Carbondale (SIUC) have collaborated to produce a digital video that highlights careers and other professional opportunities in environmental and water resources engineering. The video is targeted toward high‐school students and first‐ or second‐year college undergraduates and, thus, serves as a recruitment and retention tool for related degree programs. The video includes a series of interviews that disseminate answers to questions such as: How much education is required to be an engineer? What is the importance of licensure? Where do environmental and water resources engineers work? What salary is expected? Is engineering difficult? And do I need to be good at mathematics to be an environmental or water resources engineer? Responses are provided by current undergraduate and graduate students at SIUC. The 20‐minute video also highlights a number of experiments conducted in the SIUC engineering laboratories. A corresponding website is under construction that will include the majority of interview responses as both text and video clips. Users will be able to click on thumbnail images to hear or see different responses to the same question. The overall project is being supported by a grant from the National Science Foundation, Division of Undergraduate Education that includes the development of a CD‐ROM and web‐based database of engineering images for classroom use.

Select this Article		Case Studies for Environmental and Water Resources Systems Analysis Education David Watkins, Eric Loucks, Emmanuel Nzewi, and Avi Ostfeld ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)83 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Case study use provides for active and discovery‐based learning experiences in which students may actively acquire information about an appropriate topic, collaborate with other individuals in problem definition, develop an investigation strategy, choose among alternative problem solving approaches, and negotiate or attempt to convince others of their conclusions. Case study use also potentially engages industry and government in the university educational experience, and may encourage more undergraduate students to pursue graduate degrees. With these educational goals in mind, a set of environmental and water resources systems engineering case studies are being developed for classroom use. For each case study, students are given background information pertinent to a current water or environmental management issue, including geographic, hydrogeological, and other natural resource information; as well as any social, economic, and political information that may be relevant. A series of exercises is provided related to each case study, consisting of additional research, team participation, and computer exercises. Through the computer exercises, students will gain familiarity with technologies commonly used in the profession, including simulation and optimization models, visualization tools, and geographic information systems. This paper provides an overview of some of the case studies developed through these efforts, along with a preliminary assessment of their impact based on student and faculty evaluations. Following case study use, evaluation, and revision, the cases will be made freely available for use in water resource and environmental engineering courses at universities worldwide.

back to top

EMERGING AND INNOVATIVE TECHNOLOGIES FOR MONITORING AND FIELD DATA COLLECTION

Select this Article		San Gorgonio River Monitoring — A Case Study Catherine M. C. Avila, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)84 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper will describe a case study of the installation of scour monitoring devices on the Interstate 10 (I‐10) Bridges crossing the San Gorgonio River east of the City of Banning in Riverside County, California. The California Department of Transportation (Caltrans) required that the project area be monitored for a potential headcut resulting from a levee break protecting a large and deep gravel operation that would damage the Interstate 10 bridges upstream. The plan consists of installing monitoring equipment to have three levels of monitoring to provide a high level of redundancy. They include (1) Monitoring the recently constructed engineered levee along the San Gorgonio River, (2) Monitoring cross sections of the San Gorgonio River itself for potential headcutting, and (3) Monitoring the I‐10 bridges for scour and water surface elevation. Background information, discussion about these three levels of monitoring, implementation approach, and proposed equipment, lessons learned and construction challenges will also be discussed in the paper.

Select this Article		Electronic Field Data Collection and Data Entry for Physical Habitat Assessment on the Cheyenne River, South Dakota Cory Foreman, Andrew Patceg, and Sol Brich ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)85 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A Phase I total maximum daily load (TMDL) assessment project for the Cheyenne River Watershed in western South Dakota was initiated in the spring of 2005. A key component of this project was a physical habitat assessment of 48 sites distributed throughout the watershed. The vast amount of field work associated with this project presented an opportunity to refine field data collection methods to work toward a goal of collecting all data electronically in the field in a spatially referenced format for use with a Geographic Information System (GIS). A survey grade Trimble Global Positioning System (GPS) receiver was integrated into the field sampling procedure for sites on the main stem of the Cheyenne River, where data collection is difficult due to the size of the river and the amount of visual obstructions. GPS equipment was used to survey all pertinent stream topography data; e.g., measurements for transect spacing and cross‐sectional and longitudinal profiles. This procedure for data collection required slightly less time for postprocessing of data, converting it into a format compatible with other habitat data measurements. Significant gains were made in overall accuracy of the data and the field collection quality assurance/quality control (QA/QC). Total manhours required for data collection and data processing were reduced by up to 50 percent of those required using tape measurers and surveying levels. Additional qualitative estimates were made in the field related to habitat and vegetation as part of the sampling protocols. An ongoing effort, which began at the initiation of this project, involves developing a GIS geodatabase, linked to data entry forms, where the remaining qualitative field data can be entered. This would increase QA/QC of data collection by reducing data entry mistakes while cutting down on time spent on data entry. Once developed, metric calculations will be programmed into the geodatabase allowing for the metrics to be viewed while on location. The current goal is to have this system in place by the 2007 sampling season.

Select this Article		Design of River a Water Quality Monitoring Network: An Entropy Based Approach Mohammad Karamouz, F. ASCE, Akbar Baghvand, Amir Khajehzadeh Nokhandan, and Reza Kerachian ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)86 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Design of monitoring networks is considered as the main part of the monitoring system design including selection of the water quality variables, location of sampling stations and determination of sampling frequencies. In this study an entropy‐based approach is presented for optimal river water quality network design. In this model, the number and location of sampling sites and sampling frequencies are determined so that “redundant information” is minimized. In this methodology, a water quality simulation model is also used to generate the time series of the concentration of the water quality variables at potential monitoring sites along the river. As several water quality variables are usually considered in designing of water quality monitoring networks, pair‐wise comparison is used to combine the spatial and temporal frequencies calculated for each water quality variable. The proposed model has been used to design a water quality monitoring network for the Karoon River in the southern part of Iran. The results show that the proposed model can be effectively used for optimal design of monitoring networks. It is also shown that the redundant information can significantly be reduced by using this approach.

back to top

FOOD FOR THOUGHT AND FURTHER RESEARCH

Select this Article		Water Allocation for Wetland Environmental Water Requirements: The Case of Shadegan Wetland, Jarrahi Catchment, Iran S. Sima and M. Tajrishy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)87 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Shadegan Wetland is a Ramsar‐listed wetland in the south‐west of Iran at the head of the Persian Gulf. It is the largest wetland of Iran covering about 400,000 hectares. The wetland plays a significant hydrological and ecological role in the natural functioning of the northern Gulf. It also supports a very diverse flora and fauna and is the most important site in the world for Marbled Teal. The water regime is threatened by upstream abstraction of water for irrigation and the saline discharge from sugar cane industries and irrigation schemes. This will result in an overall reduction in wetland water quantity and quality, leading to a change in plant community composition. This paper investigates how much water is required to maintain the wetland health and the best management options to fulfill this requirement. Considering the lack of field data, using remote sensing (NOAA_AVHRR images with 1.1 km resolution), wetland monthly water surface and biomass during the 15 years before dam construction were traced. Then using these data wetland environmental water requirements was determined in 3 levels. Also the best hydrological regime that could conserve minimum requirements of vegetation cover, Marbled Teal, and flooding conditions were set as the hydrological regime with exceedance probability of 60% that is equal to 2766 MCM/y (level 3).

Select this Article		Risk Based Conflict Resolution Model for River Water Quality Management Mohammad Karamouz, F. ASCE and Ali Moridi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)88 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this study, a methodology for conflict resolution for water quality management in a river system is presented. The proposed model maximizes an objective function which is based on the Nash product which includes different utility functions related to the water quality deviations from the standards. Simulation and optimization models are proposed to determine operating policies for river water quality management, based on evaluation of the system performance to derive the most appropriate diffusing strategy for different stakeholders. The proposed model includes an integrated GA‐based optimization and a water quality simulation model. Risk‐based measures of system performance, termed reliability, resiliency and vulnerability, are calculated for each water withdrawal sector, and are combined into a Nash product, as an objective function. The model is applied to the Karkheh River system in the southern part of Iran. The utility functions are based on the acceptable risk of the allocated water quality by different sectors, especially the environmental protection agency. The results of the proposed model shows that the waste load allocation policies can significantly reduce the number and duration of violations from the standards.

back to top

INNOVATIVE WATER TREATMENT TECHNOLOGIES

Select this Article		Evaluation of Ceramic Filtration for Drinking Water Treatment in Small Systems Rajib Sinha, P.E., E. Radha Krishnan, P.E., Nur Muhammad, Ph.D., P.E., Craig L. Patterson, P.E., and Roy C. Haught ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)89 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract There are approximately 50,000 small community systems and 140,000 non‐community systems serving over 25 million transient and non‐transient populations of 3,300 people or less. Several of these small systems are having difficulty complying with the ever increasing number of regulations and regulated contaminants and it is estimated that small systems contribute 74% of the Safe Drinking Water Act (SDWA) and its Amendments (SDWAA) violations annually. Nearly 90% of these are for Maximum Contaminant Level (MCL) violations. EPA conducts in‐house technology development and evaluation to support the small communities. As part of this research effort, EPA has been evaluating a ceramic filtration system for the production of drinking water. The system is being challenged with various turbidity levels, Cryptosporidium (using polystyrene latex beads as a surrogate) and Bacillus Subtilis (to evaluate bacteria removal). This paper presents the results of studies conducted to date on this system. Future research efforts will include testing the system for removal of total coliforms, MS2 bacteriophage and Cryptosporidium parvum.

back to top

INTERDISCIPLINARY MODELING FOR AQUATIC ECOSYSTEMS

Select this Article		Agent‐Based Approach Enhances Conventional Aquatic Habitat Description & Species Utilization Methods R. A. Goodwin, D. L. Smith, J. M. Nestler, J. J. Anderson, L. J. Weber, and R. L. Stockstill ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)90 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable water resource management requires a “first principles” based understanding of the relationship between environmental stimuli and habitat utilization by target aquatic biota. This understanding is the critical foundation upon which flow management tools are developed that accurately forecast how habitats (and ultimately the aquatic populations they support) change in response to alternative water resource management plans. Emerging methods provide highly resolved descriptions of the physicochemical regimes that influence individual animal movement to supplement methods to accurately track movements of individuals. Emerging methods can be integrated using a Eulerian‐Lagrangian‐agent method (ELAM) in which (1) the Eulerian framework is used to describe the physical, hydrodynamic, and water quality domains, (2) the Lagrangian framework is used to describe sensory perception and movement trajectories of individuals, and (3) the agent framework is used to describe the behavior decisions of individuals. We discuss a generalized conceptual foundation for describing environmental habitat and stimuli in a manner consistent with animal perception and compatible with ELAM models.

Select this Article		Managing Water Levels and Flows for Improved Economical, Environmental and Ecological Benefits in Lake Ontario and in the St. Lawrence River Daniel P. Loucks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)91 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A five‐year $20,000,000 study of how Lake Ontario and the St. Lawrence River can be better managed has just come to a conclusion. Three alternative operating policies that balance competing objectives in different ways have been presented to the International Joint Commission for their consideration. After due public discussion, the IJC will be selecting one (or none) of those three to implement, with the primary purpose of improving the environmental and ecological state or quality of the basin over what it is now. At the same time the policy has to meet other objectives such as those related to recreational and commercial boating and navigation, hydropower, shoreline protection, water supply reliability, and flood protection. This paper and talk summarizes the manner in which this joint Canadian and US study arrived at economic, environmental and ecological indicators whose values were functions of what can be managed, namely lake and river levels and river flows. Also of interest is the political process of plan selection and implementation, and the institutional impact of adapting a new policy for managing water in the basin.

back to top

HUNTER ROUSE 100TH ANNIVERSARY

Select this Article		Hunter Rouse, Hydraulician: An Overview of His Work R. Ettema ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)92 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hunter Rouse (1906–1996) is credited and admired as the exemplar researcher and educator who championed the application of fluid mechanics theory, and contemporary experimentation methods, to water flow processes in hydraulic engineering. This application, commonly called hydraulics, placed much of hydraulic engineering on a substantially more rational basis than had prevailed a century ago. This paper is an overview of Rouse's work.

Select this Article		Hunter Rouse's Historical Writings and the History of Hydraulics Rare Book Collection C. F. Mutel, D. L. Daly, and R. Ettema ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)93 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract As Hunter Rouse matured, he became increasingly involved in studies of the history of fluid mechanics and hydraulics. Rouse's interest led him to produce two books on the subject, many articles, numerous lectures, and an unusual collection of rare historic books. The collection holds over 500 volumes and spans approximately 500 years. Housed at the University of Iowa, the collection remains a valuable resource for historical research. This paper describes Rouse's history research and writing, as well as the History of Hydraulics Rare Book Collection that he created.

Select this Article		ASCE Manual of Practice 110—Sedimentation Engineering: Processes, Measurements, Modeling, and Practice Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)94 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract ASCE Manual 54 “Sedimentation Engineering,” edited by the late Professor Vito A.Vanoni, provides both qualitative and quantitative guidance to theoreticians and practitioners with respect to sediment issues and processes associated with the development, use and conservation of water and land resources. It describes the nature and scope of sedimentation problems, details methods of investigation, and presents practical approaches to solution and management. As a major contribution to the profession, Professor Vanoni organized, partially wrote, and edited the definitive Manual 54. As chairman of the special Task Committee, established in 1954 with the charge of writing the manual, Vanoni worked for two decades and set a high standard. Many of the sections of the original manuscript for the book were first published in the Journal of the Hydraulics Division ASCE and received considerable discussion, which was taken into account in the final manuscript. Manual 54 received worldwide recognition and widespread use in academia and practice, being recognized with the ASCE Karl Emil Hilgard Hydraulic Prize for best publication in 1976. Since the publication of Manual 54 in 1975, global awareness of sediment erosion, transport and deposition processes and of their impact on the use and development of water and land resources has greatly increased. Manual 54 remains an important reference on many aspects of sedimentation engineering, but in other aspects it has been outdated by advances in knowledge and techniques and by the emergence of new problems and issues.

back to top

PAST, PRESENT, AND FUTURE OF THE PICK‐SLOAN PROGRAM

Select this Article		History of the Pick‐Sloan Program Paul Johnston ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)95 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Congress passed the Flood Control Act of 1944, the Pick‐Sloan Plan. It was a marriage of two plans developed by Brig. Gen. Lewis A. Pick of the Army Corps of Engineers and W. Glenn Sloan of the Bureau of Reclamation. The Sloan plan called for irrigating millions of acres of land with water impounded behind dams on the Missouri and numerous tributary rivers, thereby providing construction and farming jobs to encourage people to return to the upper Midwest following years of drought and war. The Pick plan emphasized flood control, navigation, water supply and hydropower generation primarily from reservoirs on the main stem of the Missouri. Signed by President Roosevelt on December 22, 1944, the act authorized the construction of five large dams on the Missouri River to be built and operated by the Corps. In addition, there were numerous tributary structures and giant irrigation projects to be built and operated by the Bureau. In all, it authorized eight purposes: flood control, navigation, irrigation, hydropower, water supply, water quality, recreation and fish and wildlife.

Select this Article		Past, Present, and Future of the Pick‐Sloan Program for the Missouri River Basin: Operations of Dams under the Pick‐Sloan Program Larry J. Cieslik ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)96 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper/presentation covers the current operation of the six mainstem dams comprising the Missouri River Mainstem Reservoir System (System) to serve Congressionally authorized purposes. Congress authorized the construction of these dams for flood control, recreation, irrigation, water supply, water quality, navigation, hydropower, and fish and wildlife. The Endangered Species Act also added the requirement to provide special emphasis for Federally listed threatened and endangered species that may be affected by the operation of the System. The System Master Water Control Manual (Master Manual) describes the operation of the six dams as a system to serve the Congressionally authorized project purposes.

back to top

ENVIRONMENTAL PROCESSES I

Select this Article		Antibiotic Resistance Genes (ARG) as Emerging Environmental Contaminants Ruoting Pei, Heather Storteboom, and Amy Pruden ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)97 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We are investigating antibiotic resistance genes (ARG) as emerging contaminants in the environment. The spread of ARG is a growing concern considering the increasing microbial resistance to antibiotics that is being observed world‐wide. The development and spread of ARG responsible for imparting antibiotic resistance has been associated with the widespread use of antibiotics in livestock as well as humans. The purpose of this study was to quantify the occurrence of antibiotic resistance in the mixed‐landscape Cache La Poudre River watershed, which has previously been studied and shown to have high concentrations of antibiotics correlating with urban and agricultural activity. In order to detect and quantify ARG in various environmental compartments, molecular biological methods were developed and applied to the environmental samples. Polymerase chain reaction (PCR) detection assays were conducted for seven sulfonamide resistance gene families using newly designed primers and eight tetracycline resistance gene families using previously published primers. Sul(I), sul(IT), tet(W), and tet(O) gene families were further quantified by real‐time quantitative polymerase chain reaction (Q‐PCR). Resistance to four classes of antibiotics (tetracyclines, sulfonamides, ionophores, and macrolides) was also investigated using a culture‐based approach on antibiotic media. ARG were found to be present in river sediments, and their concentrations correlated to human and agricultural activity. The quantities of ARG normalized to the 16S rRNA gene copy number were statistically different between the sampling sites with different levels of human and agricultural input, and the pristine site being the lowest in all sampling events. These results suggest the need for increased involvement of environmental engineers to help understand the pathways of ARG in the environment and to develop treatment and mitigation strategies for minimizing the spread of ARG in the environment.

Select this Article		Natural Bank/Bed Filtration: Water Supply Schemes in Uttaranchal, India R. R. Dash, I. Mehrotra, and P. Kumar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)98 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Natural purification of water from rivers and lakes through bank and bed filtration has been shown to be quite effective in the state of Uttaranchal (Longitude 77° 34′ 27″ to 81° 02′ 22″ E and Latitude 28° 53′ 24″ to 31° 27′ 50″ N), India. The subsurface water under the direct influence of surface water is being tapped by (i) tube‐wells in Nainital, (ii) infiltration wells in Hardwar, and (iii) uttaranchal wells in adjoining hilly areas of Dehradun. This paper presents quality of surface and subsurface water at three sites. Cost effective water supply schemes have been developed on the basis of lake, bank filtration, river bank filtration and river bed filtration. At Nainital, five tube‐wells of different depths (22.6m – 33.35m) are in use to tap the subsurface water from the unconfined aquifer hydraulically connected to lake water. Lake water as such is not potable as it contains unacceptable levels of organic matter in terms of COD (∼ 31 mg/L), coliform (∼ 17 × 10⁴ MPN/100 mL) and nutrients. On the other hand coliform bacteria, organics and nutrients have not been detected in any of the well water samples over the years. Sixteen infiltration wells located on the bank of the river Ganga and Ganga Canal at Hardwar get water from the unconfined aquifer hydraulically connected to the river and canal. Distance of the infiltration wells from the river/canal varies from 4 to 90m at different locations. Up to 3 log turbidity reduction and 4 log fecal coliform removal (MPN) is achieved through natural bank filtration. The hilly streams normally have permeable strata just below their bed, saturated with water and having continuous sub‐surface flow by gravity. Uttaranchal Well is embedded below the stream bed to tap this continuous sub‐surface flow which is in direct connectivity with the surface water above it. It is being used successfully for more than 300 rural water supply schemes in different districts of Uttaranchal. Water quality analysis of samples taken from these wells and source water for Dehradun district is carried out in monsoon, the worst season to assess effectiveness of bank/bed filtration. Fecal coliform count and turbidity of water collected from Uttaranchal Wells is 30 times less than that of stream water. River/stream water is highly turbid particularly during rainy season while well waters are quite clear. These improvised‐innovation adapted are operative, almost maintenance free, economical, and sustainable.

Select this Article		Sedimentary Phosphorus and Arsenic Inactivation in an Alum‐Treated Lake Erica Scheckel and John L. Durant, Ph.D., P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)99 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract High fluxes of sedimentary phosphorus (P) in Spy Pond in Arlington, MA have increased the rate of eutrophication and diminished the recreational value of the pond. The pond sediments are also contaminated with arsenic, which was applied in the 1950s and 1960s to control macrophyte growth. Arsenic (As) is chemically similar to P and remobilizes from the sediments under the same conditions that give rise to P remobilization. The remobilization of P and As are controlled by redox conditions in the bottom waters of the pond: reducing conditions cause P and As adsorbed to sediments to desorb and enter the water column from late spring until fall. To control P remobilization, the pond was treated with alum in May 2004. The goal of our study was to determine whether alum was also effective for controlling As remobilization. Data was collected to monitor the change in average peak concentrations of P and As before and after treatment. The pond is separated into two basins, north and south, by an island and shallow sill. The two basins have unique water chemistry characteristics and the responses to the alum treatment differ. In the south basin, the P concentration ratio before and after treatment was 13:1, while the ratio for As was only 2:1. The ratios for P and As in the north basin were 5:1 and 3:1, respectively. Data collected from Spy Pond indicate As(III) was not significantly inactivated by alum. The effectiveness of the alum to control As remobilization is dependent on the As redox state and competition with P for adsorption sites.

back to top

ENVIRONMENTAL PROCESSES II

Select this Article		Environmental Management of the Three Gorges Project Jian Liu, Ph.D., M. ASCE, Zhiyu Sun, Ph.D., Yongbai Chen, and Peng Lou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)100 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The environmental management of the Three Gorges Project is discussed in this paper. The management experiences and methods during the periods of the feasibility study, construction, and partial operation are described in detail. The pollution control management in the reservoir area is described. The resettlement problems are discussed in brief. Some suggestions for the environmental management are presented from the viewpoint of sustainability management. People‐centered management should be promoted in the future operation. The environmental monitoring and investigations should be further made to fully understand the environmental realty related to the dam operation, the reservoir inflow and outflow, sedimentation and the resident's lives around the reservoir. The mitigation measures should be executed to reduce the negative impacts of the Three Gorges Project. The environmental management experiences can be used for other hydropower projects to heighten the management level of the hydropower industry.

Select this Article		Third‐Party Environmental Audit — A Tool for Industrial Environmental Compliance S. Rao Chitikela, Ph.D., P.E. and Suresh Chandran, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)101 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Industrial facilities environmental, health and safety (EH&S) audits are accomplished via either self and/or third‐party audit(s). The periodic third‐party environmental audit of industrial facilities is included to verify the facility compliance with various environmental requirements of a given geographical location, and evaluate facility's routine environmental control practices. The third‐party environmental auditor would be responsible for conducting a comprehensive review of facility's operations and confirming whether the facility is in environmental compliance. This paper included: pre‐audit communications and the review of facility environmental information; site environmental‐audit elements and audit conductance; and, the post‐audit review of facility operations information and preparation and submission of the final audit report. The environmental audit should include all applicable environmental regulatory and permitting requirements of state, federal, and local regulating agencies.

Select this Article		Air Permitting and Reporting for Public Landfills and POTWs F. Jason Martin, P.E., M. ASCE and Thomas A. Henning, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)102 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Landfills and publicly owned treatment works (POTW) emit pollutants to the air from many sources, most notably fugitive and combustion sources. Flares are commonly used at landfills and POTWs to burn landfill gas and digester gas generated at the plants. Many owners and operators of these facilities are unaware that operation of combustion equipment such as a flare can trigger state air permitting and annual emission reporting requirements. Flares generate a relatively large amount of carbon monoxide (CO), a regulated pollutant. CO is the pollutant that usually exceeds regulatory thresholds. To confuse the situation further, each state enforces different thresholds. Owners and operators of a landfill or POTW should calculate plant emissions and determine their regulatory obligations. Ironically emissions from wastewater treatment systems and solids handling operations at POTWs do not usually exceed regulatory thresholds, even though emissions from these operations are subject to the most public scrutiny. Combustion of digester gas is the activity that typically creates air quality permitting requirements. This paper presents several sources of air emissions common to landfills and POTWs along with typical regulatory considerations that would apply.

Select this Article		Upgrading a Small Wastewater Treatment Plant for the 21^st Century Thomas T. Satchell, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)103 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Fremont, Nebraska, is a city of approximately 25,000 people located in Eastern Nebraska. The city is served by a wastewater treatment plant (WWTP) originally constructed as a primary treatment plant in the 1960s and subsequently expanded to secondary treatment in the 1970s. Wastewater treatment plants are typically designed for a life of 20 – 25 years for process equipment while structures are expected to serve longer. In the early 1990s, the City of Fremont began planning for the future of wastewater treatment for their community. This planning effort was necessitated for the following reasons: (1) Regulatory agency discharge permit modifications, (2) Implementation of the Part 503 Regulations, (3) Treatment technology changes, (4) Aging of existing systems, and (5) Capacity issues for both liquid and solids stream. In 1991, the City of Fremont retained Jacobson Helgoth Consultants (JHC) to prepare a Facility Plan to address the long‐term needs of the City's Wastewater Treatment Plant (WWTP). Once the Facility Plan was completed and approved by the regulatory agency, design of new facilities began. The project was accomplished in phases to meet funding limitations and allow for an orderly flow of construction while still maintaining all treatment processes in operation. The construction was completed in 2002 at a cost of $18,000,000. The plant consistently meets its discharge permit limitations and the requirements for disposal of stabilized biosolids. All systems have been updated to reflect the latest in treatment and equipment technology and the city has treatment capacity to meet it needs for the foreseeable future. As a result of these upgrades and modifications, the City of Fremont has a wastewater treatment plant that will serve it well for the first two to three decades of the 21^st century.

back to top

ENVIRONMENTAL PROCESSES III

Select this Article		Aeration Performance of a Hydraulic Jump S. Kucukali and S. Cokgor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)104 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hydraulic jump is occurred at the transition from supercritical to subcritical flow which is characterized with energy dissipation due to highly turbulent flow, air entrainment, and macro‐scale vortices. In this study self‐aeration performance of a classical hydraulic jump beyond a sluice gate, has been investigated in a 0.5 m wide flume. Experiments were conducted for a range of upstream Froude numbers 2–6, and unit discharges 2×10⁻² – 5.3×10⁻² m³/sm. It was appeared that the aeration efficiency of a hydraulic jump was mostly dependent on head loss, and then to the unit discharge positively. Further, turbulence structure of the hydraulic jump, which ensures the entrainment of air into water, was highlighted by using an Acoustic Doppler velocimeter at low Froude numbers. An empirical formula predicting aeration efficiency for hydraulic jumps was developed by using non‐linear regression analysis. Good agreement between measured and predicted aeration efficiency values was obtained.

Select this Article		Impacts of Inundation of Houziyan Reservoir on Zang Nationality Blockhouse Group Relics along the Dadu River Shengwen Qi, Faquan Wu, Changgen Yan, and Zhuping Sheng ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)105 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Ancient blockhouses relics are representative culture of Zang nationality in China, which have attracted a great interest of archaeologists around world because of their unique historical, cultural and scientific values. However, the rising water level in Houziyan reservoir may pose threats to the stability of slope and in turn damages to the blockhouses located on the slope. In this paper, the authors characterize the origin of Suopo deposits, analyze structures and failure mechanisms of the blockhouses, and assess current status of slope stability and its change after inundation. Preliminary results indicate that Suopo slope is stable under current condition with localized non‐uniform deformation and variable submersion, which had caused collapse of some ancient blockhouses. At a normal pool water level (NPL) of 1852 m, the slope is stable as whole after inundation of Houziyan reservoir. However, some slumps and rock falls may occur near the edge of the rising water or at the toe of slope. With appropriate protection of the slope toe and prevention of slumps and rock falls, impacts of inundation of the reservoir can be minimized, and the blockhouses can be protected.

Select this Article		Dissolved Oxygen Modeling of Lake Ogallala: A Midwest Hydropower Tailwater Reservoir Using CE‐QUAL‐W2, Version 3 L. Kozimor, J. Stansbury, E. Dove, and D. Admiraal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)106 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Lake Ogallala hydropower tailwater reservoir is subjected to wide fluctuations of the inflow water quality and quantity. These alterations impact lake temperatures, water stage, dissolved oxygen (DO) and nutrients. A two dimensional continuous simulation, hydrodynamic and water quality model, CE‐QUAL‐W2, was used to simulate the lake's dissolved oxygen. The elements modeled include surges of low DO and temperatures; high chemical oxygen demands and dissolved nutrients; in‐lake algae, macrophytes, and epiphytes response; temperature and bathymetric induced circulation patterns; and weather impacts. The epiphyte routine was used to simulate macrophytes, and the model was able to emulate the diurnal DO and temperature fluctuations which ranged from 2 to 12 mg/L and 19.5 to 23 degrees C, respectively. The study found that the chemical demand resulted in an approximately 1.5 mg/L drop in DO across the lake but also found that macrophyte respiration causes approximately a 2 mg/L reduction in DO during dark respiration. Management alternatives were modeled based on controlling the inflow of DO and macrophyte harvesting.

back to top

ENVIRONMENTAL PROCESSES IV

Select this Article		Using Neural Network to Investigate the Environmental Impact of an Abandon Landfill S. A. Mryyan and Y. M. Najjar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)107 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Advances in technology are allowing scientists and engineers to perform their jobs in ways that are both more time‐efficient and cost‐effective. With the number of abandoned landfills increasing every year, it is essential that the cost of investigation and remediation of such sites remain as low as possible. To achieve this objective, many site investigator teams are choosing to employ the powerful function approximation feature of artificial neural networks (ANN). Once the desired ANN profiling system is trained on existing data, the system can be used to produce efficient predictions for the unexplored regions. Similar ANN profiling systems were utilized herein in the investigation of an abandoned landfill site in Kansas City, KS. The developed ANN systems were trained on existing data and then were used to predict the amounts and distribution of arsenic and lead contaminates within the landfill area. The site investigating team was able to capitalize on the information generated via the developed ANN systems in order to determine the strategic locations for further testing. Therefore, less money was spent since no further testing was needed in the relatively uncontaminated regions.

Select this Article		Wetland Treatment of MTBE Contaminated Groundwater at a Local Refinery M. Raynal, T. Sale, and A. Pruden ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)108 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this study was to explore the potential of wetlands for bioremediation of a methyl tert‐butyl ether (MTBE) spill at a Colorado refinery where other contaminants present at the site have potential to inhibit MTBE biodegradation. MTBE biodegradation has been observed to be inhibited by the presence of other contaminants that are common at refineries, such as Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX). MTBE biodegradation is also typically limited by availability of oxygen, and only rarely has been observed to degrade under anaerobic conditions. To test the feasibility of MTBE bioremediation, a bench‐scale study followed by a pilot‐scale study in the field were conducted. The bench‐scale studies were performed as batch tests in which two enrichment cultures were compared for their ability to degrade MTBE in the presence of BTEX. It was observed that culture MO (originally enriched only on MTBE) was superior to culture MB (originally enriched on MTBE and BTEX) in terms of its ability to degrade MTBE. However, both cultures showed inhibited degradation of MTBE in the presence of BTEX. Interestingly, when the MO culture was placed in a semi‐batch reactor, simultaneous MTBE and BTEX biodegradation was observed. This suggests that metabolic by‐products accumulated in the batch tests may inhibit the ability to degrade MTBE in the presence of BTEX. It was thus hypothesized that in a continuous‐flow system, such as a wetland, MTBE and BTEX will degrade simultaneously. In the second part of the study, pilot wetlands are now being tested at the refinery. The wetlands consist of 30‐gallon aquaria filled with sediments from the Sand Creek near Denver, CO. The feed water to the systems is taken directly from the pre‐treated water from an air‐stripper that is currently in operation at the refinery. Six different conditions are being tested in which the inoculum, Fe(III) availability are being tested. Molecular analysis will be used to gain insight into the effect of the microbial community and to assess bioremediation potential at the site. The results of the pilot‐scale study will thus serve to guide the design of the full‐scale wetland study. It is expected that the complex environment and flow‐through conditions of a wetland will promote simultaneous biodegradation of MTBE in the presence of multiple co‐contaminants.

Select this Article		Microbiology of Two Sulfate‐Reducing Field Bioreactors Used for the Remediation of Mining Influenced Water L. P. Pereyra, A. Pruden, S. R. Hiibel, L. Y. Inman, N. Kashani, K. F. Reardon, and D. J. Reisman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)109 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sulfate‐reducing permeable reactive zones (SR‐PRZs), such as anaerobic wetlands, sulfate‐reducing bioreactors, and permeable reactive barriers, rely on microbially‐mediated processes to treat mining influenced waters (MIWs) contaminated with heavy metals. The remediation is accomplished through the precipitation of metal cations with sulfide produced by sulfate‐reducing bacteria (SRB). The microbial communities in SR‐PRZs are very complex and include not only SRB but also cellulose degraders and fermenters that provide SRB with the substrates necessary for their growth. Even though microorganisms are the driving force in SR‐PRZs, little is known about the microbiology of these passive mine drainage treatment systems. We have recently developed a suite of molecular biology tools in our laboratory for characterizing the microbial communities present in SR‐PRZs. In this study our suite of tools is used to characterize two different field bioreactors: Peerless Jenny King and Luttrell, near Helena, MT. Both bioreactors employ a compost‐based substrate to promote the growth of SRB. The two bioreactors were sampled at multiple locations and depths in June, 2005, and Peerless Jenny King was sampled again in August, 2005. Cloning of polymerase chain reaction (PCR) amplified 16S rRNA genes followed by restriction digest screening and DNA sequencing provided insight regarding the overall composition of the microbial communities. To directly examine the SRB populations, two approaches were used. In the first approach, a gene specific to SRB, ApsA, was PCR‐amplified, cloned, and sequenced. This revealed that two main SRB groups are prevalent in both Luttrell and Peerless Jenny King, both of which are Desulfovibrio spp, and one of which is noted to be particularly aerotolerant. This analysis also revealed the presence of Thiobacillus denitrificans, an organism that oxidizes sulfides in the presence of nitrate or oxygen, which has been considered highly undesirable for bioreactor function. In the second approach, quantitative real‐time PCR (Q‐PCR) was used to quantify two specific groups of SRB, Desulfovibrio and Desulfobacter. These two SRB groups were found to vary in distribution between the two bioreactors and with depth. The results of this study indicate that two different SR‐PRZs also have two very different microbial communities. The ultimate goal will be to develop an improved understanding of the microbiology of SR‐PRZs in order to improve design and operation of these treatment systems.

back to top

COMPARISON AND ESTIMATED USAGE OF ASCE/EWRI MODEL WATER CODES

Select this Article		Comparing the Regulated Riparian and Appropriative Rights Model Water Codes Joseph W. Dellapenna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)110 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The American Society of Civil Engineers launched the Model Water Code Project in 1990 under the leadership of Ray Jay Davis. I took over direction of the project in 1995 after Professor Davis retired. We have now completed the Regulated Riparian Model Water Code, which is standard 40‐03 of the Society. The Appropriative Rights Model Water Code has been completed as a report of the Laws and Institutions Committee of Environmental and Water Resources Institute, with balloting on it as a standard about to begin. While efforts were made to make the provisions of the two model codes the same insofar as possible, the two model codes represent the two very different regulatory approaches to water management issues now prevalent in the United States. A close comparison of the two model codes thus serves as an introduction to the provisions of the codes and serves to introduce the major legal issues regarding water management and possible legal responses to those water management issues. This paper will be the first such comparison since the completion of the report version of the Appropriative Rights Model Water Code.

back to top

INTERNATIONAL INVOLVEMENT IN ASCE/EWRI COMPREHENSIVE WATER QUALITY STANDARD AND CRITERIA

Select this Article		Progress on Creating a Model Agreement on Transboundary Water Quality Mangement with Guidelines for the Development of Border Water Quality Standards, Management Plans and Effective Agreements Mark W. Killgore, P.E. and David Eaton, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)111 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Border International Water Quality Standards Committee of EWRI is developing a major document revision that will add two appendices to the previously published “Comprehensive Transboundary International Water Quality Management Agreement.” The new version is tentatively retitled “Comprehensive Transboundary Water Quality Management Model Agreement with Guidelines for the Development of Standards, a Management Plan, and Effective Agreements.” The document development follows the established process for ASCE standards, as discussed below. The purpose of the upcoming “Comprehensive Transboundary Water Quality Management Model Agreement (model agreement) with Guidelines for the Development of Standards, Management Plan, and Effective Agreements” is to provide a framework for bi‐ or multi‐lateral agreements that form the policy and regulatory structure for establishing a partnership between sovereign countries or nations (Parties) to provide comprehensive water quality management of shared water resources along or across intergovernmental boundaries. This model agreement and the appendices will provide a step‐by‐step approach to implementation of an agreement of this type is based on the concept of shared sovereignty. It is appropriate only for those situations in which the Parties are prepared to relinquish a significant degree of sovereignty over their portion of the shared water resource. Work describing the development of the model agreement was previously published.

back to top

EVOLUTIONARY COMPUTATION FOR MODEL CALIBRATION

Select this Article		Evolutionary Algorithms for Multi‐Objective, Automatic Calibration of a Semi‐Distributed Hydrologic Model Elias G. Bekele and John W. Nicklow, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)112 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Calibration of hydrologic models has traditionally been performed with respect to a single performance metric. This type of calibration, however, is often inadequate to properly evaluate the simulation of important characteristics of a hydrologic system. This paper presents a multi‐objective, automatic calibration model, which is developed using an evolutionary optimization technique known as Strength Pareto Evolutionary Algorithm 2 (SPEA2). SPEA2 is a multi‐objective search algorithm that employs the concept of Pareto dominance for selection of better solutions. The calibration model is integrated with the U.S. Department of Agriculture's Soil and Water Assessment Tool (SWAT). SWAT is a physically‐based, semi‐distributed hydrologic model that was developed to predict the long term impacts of land management practices on water, sediment and agricultural chemical yields in large complex watersheds with varying soils, land use, and management conditions. Being a semi‐distributed model, SWAT consists of a large number of parameters to capture the various physical characteristics of a hydrologic‐defined unit. In order to reduce the number of calibrable parameters to a manageable size, parameterization was performed. In this study, SWAT was calibrated for daily streamflow and sediment. The calibration process was formulated as a multi‐objective optimization problem, and it involves parameter specification, whereby sensitive model parameters are identified, and parameter estimation. The methodology is demonstrated using Big Creek watershed in southern Illinois. The model finds Pareto optimal solutions for the calibration problem, which are sets of model parameters. Application results show that model predictions are significantly improved and that the use of multiple calibration objectives results in better model performance.

Select this Article		Using Genetic Algorithms and Particle Swarm Optimization for Optimal Design and Calibration of Large and Complex Urban Stormwater Management Models Misgana K. Muleta, Paul F. Boulos, Chun‐Hou Orr, and Jun Je Ro ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)113 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Computer models are vital for the evaluation and management of urban drainage systems. Usefulness of these models, however, depends on how well they are calibrated. Properly calibrated models can be used to conceive, evaluate and compare various design improvement alternatives. Unfortunately, calibration and design of urban stormwater models, especially with the commonly used trial‐and‐error approach, are an expensive, time‐consuming process and normally represent the most painful step of a modeling exercise. Their success depends mainly on the engineering expertise of the modeler and budget availability. The effort is complicated by the fact that these models normally necessitate the evaluation of a large number of variables and parameters in order to adequately describe the complex relationships that exist between rainfall, runoff, watershed characteristics, and system hydraulics in an urban setting. The trial‐and‐error evaluation of all calibration and design/improvement options is therefore unlikely to be practically feasible or manageable, and even knowledgeable modelers often fail to obtain good results. In this paper, a rigorous optimal calibration and design methodology is presented, which eliminates the need of the traditional trial‐and‐error technique. The optimal calibration and design problems are cast as nonlinear optimization problems and solved using genetic algorithms (GA) optimization and particle swarm optimization (PSO). The EPA storm water management model (SWMM5) is employed to perform hydrologic and hydraulic analyses. The optimal calibration model determines the set of calibration parameters that best matches field observations of flow, depth or velocity to accurately mirror actual system performance. The optimal design model determines the set of design parameters that best meets desired system performance requirements at minimum cost. Design parameters can include any combination of pipe slope and size, storage, pumping, and new piping. System performance criteria include explicit constraints on the maximum allowable depth to diameter ratio, minimum and maximum pipe velocities, and maximum head loss for force mains. The proposed optimal calibration and design models are demonstrated by application to an example urban stormwater collection system. Enhancement of urban drainage system planning, design, operation and management is a principal benefit of the proposed methodology.

Select this Article		Calibration of CAEDYM Using a Genetic Algorithm — the Lake Kinneret Case Study Avi Ostfeld, M. ASCE, Gideon Gal, and Elad Salomons ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)114 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a general mathematical calibration model for the parameterization of CAEDYM, and its implementation to Lake Kinneret as a case study. CAEDYM along with DYRESM form a 1D aquatic ecosystem model that can simulate the physical, biological and chemical processes of lakes and reservoirs. CAEDYM is the biological‐chemical model and describes primary production, secondary production, nutrient and metal cycling, oxygen dynamics, and the movement of sediments. Lake Kinneret (the Sea of Galilee) is the most important surface water resource in Israel providing approximately 35% of its annual drinking water, a proportion that is constantly increasing. The lake surface is approximately 212 m below the level of the Mediterranean Sea, its maximum volume is 4.3 Billion Cubic Meters (covering an area of about 167 km²), its maximum length (north to south), width (east to west), and depth, are 24 km, 16 km, and 44 m, respectively. The calibration model, entitled CalKin, couples a genetic algorithm with CAEDYM. The model performance has been shown to be robust and reliable achieving significant improvements over manual calibration.

Select this Article		Interactive Multi‐Objective Inverse Groundwater Modeling — Formulation and Addressing User Fatigue Abhishek Singh and Barbara Minsker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)115 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper builds on work done on using interactive multi‐objective genetic algorithms (IMOGA) to solve the groundwater inverse problem (Singh & Minsker, 2005) by searching for optimal hydraulic conductivity fields conditioned on field measurements of hydraulic heads and conductivities. The biggest challenge faced when using such interactive systems is that of user fatigue because the user is expected to evaluate many solutions during the search process. This paper discusses a two‐step approach to reduce user fatigue. First the user is shown only a fraction of the total population in every generation. To ensure minimum redundancy during evaluation, the solutions are clustered using unsupervised clustering and the expert is shown unique samples from distinct clusters. Next the unranked solutions are ranked using a surrogate model that ‘learns’ from the user preferences. This is implemented using a supervised classification algorithm to cluster the solutions based on the 2‐D images of hydraulic conductivity. We test ‘content‐based’ and ‘spectral’ algorithms for the clustering and classification as these have been shown to be similar to how humans process images. The work on applying and testing these algorithms is on‐going and this paper discusses some preliminary results. Complete results will be shown at the EWRI conference.

back to top

GROUNDWATER SYSTEMS APPLICATIONS

Select this Article		A Collaborative Interactive Genetic Algorithm Framework for Mixed‐Initiative Interaction with Human and Simulated Experts: A Case Study in Long‐Term Groundwater Monitoring Design Meghna Babbar and Barbara Minsker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)116 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Interactive Genetic Algorithm (IGA) allows water resources and environmental decision makers to become active online participants during the optimization process, and thus provides a method to include qualitative expert knowledge within the search criteria. However, various interfering human factors, especially human fatigue, can limit the extent of the decision maker's participation. In this paper, we propose a mixed‐initiative interaction technique for the IGA in which a simulated expert (created by using a machine learning model) can share the workload of interaction with the human expert, while constantly learning her/his preferences. This collaborative framework also allows the system to observe the learning behaviors of both the human and simulated expert, while utilizing their knowledge for search purposes. Many machine learning models can be utilized for creating the simulated experts, in our work we use fuzzy logic modeling that implements a rule based decision making criteria for modeling the human expert's preferences. These methodologies are tested on a field scale groundwater monitoring application to analyze their benefits.

Select this Article		Use of Surrogate Models for a Groundwater Pollutant Source Characterization Problem Emily M. Zechman, Baha Mirghani, Matthew Clayton, G. Mahinthakumar, and S. Ranji Ranjithan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)117 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper investigates a groundwater source identification problem in which concentrations at observation wells are used to reconstruct the pollution loading scenario. This inverse problem is solved using a simulation‐optimization approach using evolutionary algorithms to conduct the search. Varying levels of complexity may be modeled, leading to different levels of accuracy in predictions of source location, size, and concentration. More complex models will increase the computational effort needed to model pollutant transport as part of a search procedure. In addition, the amount of non‐uniqueness will typically increase as the complexity of the problem increases. This paper describes an investigation of surrogate modeling procedures and methods to generate very different solutions to characterize groundwater pollutant source under varying degrees of problem complexity.

Select this Article		An Algorithm for Groundwater Long‐Term Monitoring Spatial Optimization by Analogy to Ant Colony Optimization for TSP Yuanhai Li and Amy B. Chan Hilton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)118 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A methodology for optimizing groundwater long‐term monitoring (LTM) is presented. Groundwater LTM is required to assess the performance of groundwater remediation and human being health risk at post‐closure sites where groundwater contaminants are still present. Some monitoring wells in the existing LTM network may be redundant, making it possible to remove some of them without compromising data quality. An optimization algorithm based on the ant colony optimization (ACO) paradigm is developed to minimize the overall data loss by identifying a given number redundant sampling locations. The ACO method is inspired by the ability of ant colony to identify the shortest route between their nest and a food source. The algorithm searches for redundant wells from among sampling locations in the monitoring network and follows steps analogous to traveling salesman problem (TSP), which is a cardinal combinatorial problem successfully solved by ACO. Results from the developed ACO‐LTM algorithm show global optima or near‐optimal solutions were identified. A comparison of the ACO‐LTM results to those from complete enumeration indicates that the developed ACO‐LTM algorithm is efficient and effective.

back to top

METHODOLOGICAL ADVANCES AND THEORY

Select this Article		Efficient Strategies for Sampling Uncertain Parameters in a Genetic Algorithm‐Based Chance‐Constrained Watershed Water Quality Management Problem Kwisun Park Yu and Laura J. Harrell, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)119 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Chance‐constrained genetic algorithms (CCGAs) can identify efficient solutions to complex water resources and environmental problems that satisfy a criterion with a specified likelihood under uncertainty. However, because they require evaluation of potential solutions numerous times using realizations of uncertain parameters, the computational time requirements can be very large. This paper investigates the effectiveness and efficiency of various strategies for sampling uncertain parameters in a CCGA applied to a watershed management design problem. Various sample sizes, as well as strategies for sampling uncertain parameters in a CCGA, such as using a new set of realizations for each generation, using the same set of realizations for all generations, using a new set of realizations for each potential solution evaluation, and strategies that vary the sample size based on the genetic algorithm (GA) progress, are investigated for a chance‐constrained watershed management design problem. The resulting solution quality and computational requirements are compared, and recommendations are made for the most promising sampling strategies and sizes for GA‐based chance‐constrained watershed management.

Select this Article		Efficient Methods for Constraint‐Handling in Evolutionary Algorithm‐Based Management of Irrigation Canal Network Operations Talaat El Gamel and Laura J. Harrell, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)120 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Handling constraints in evolutionary algorithms (EAs) is a challenging issue, since an EA does not handle constraints directly. Thus, developing a heuristic that can guide the search toward feasible and good‐performing solutions has become a topic of considerable interest in the field of evolutionary computation in recent years. If a heuristic is applied that is not appropriate or properly fine‐tuned, the EA may converge on infeasible solutions, or on feasible solutions with poor objective function values. This paper presents a new constraint‐handling technique based on stochastic tournament selection (STS). The performance of this technique is compared to various other constraint‐handling techniques applied to a genetic algorithm‐ (GA‐) based irrigation canal management problem. The problem involves finding an efficient strategy of irrigation canal network operations that can minimize the total water consumed while preventing problems such as water shortage and flooding. The most common way to handle constraints in EAs is to incorporate penalty functions into the fitness criterion to degrade the fitness of solutions that violate one or more constraints. Alternative techniques have also been reported in the literature, including multiobjective optimization techniques that treat the constraints in single objective problems as additional objectives and stochastic techniques. This paper investigates the performance of five constraint‐handling techniques (four techniques from the literature, and the new proposed STS technique). Three scenarios of the case study, with different levels of difficulty and different numbers of constraints, are tested. A comparison of the performances is made to help provide guidelines for the most promising constraint‐handling techniques for EA‐based management of water supply and irrigation canal operations, based on the level of difficulty of the problem.

Select this Article		Optimal Reservoir Operation Considering the Water Quality Issues: Application of Adaptive Neuro‐Fuzzy Inference Systems (ANFIS) R. Kerachian, M. Karamouz, and F. Soltany ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)121 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this study, an algorithm combining an ANFIS‐based water quality simulation model and a GA‐based optimization technique is developed for determining optimal reservoir operating rules. In this paper, the Nash bargaining theory is used to resolve the existing conflict of interests as different decision‐makers and stakeholders are involved in the reservoir operation. The utility functions of the proposed models are developed based on the reliability of water supply to downstream demands, water storage, and the quality of the withdrawn water. A numerical water quality simulation model is also developed to simulate the thermal stratification cycle and the reservoir discharge quality through a selective withdrawal structure. As the water quality simulation model has a considerable run‐time, an ANFIS‐based simulation model is trained using the results of multiple simulation runs of the numerical water quality simulation model. Then the trained ANSIS model is linked with the Dynamic Genetic Algorithm (DGA). DGA can reduce the computational burden of the classical GAs and the ANFIS model reduces the simulation time. Therefore, total model run time is considerably reduced in the proposed model. The developed model is applied to the 15‐Khordad Reservoir in the central part of Iran. The results show that the model can reduce the salinity of the allocated water to different water demands as well as the salinity build‐up in the reservoir.

Select this Article		Parallelization Strategies for Evolutionary Multiobjective Optimization Yong Tang and Patrick M. Reed ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)122 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract There has been a modern confluence of environmental and water systems research towards a design paradigm that emphasizes multiple objectives for computationally intensive applications in areas including groundwater management, water distribution systems, and non‐point source pollution. To date there have been very few parallel evolutionary multiobjective applications world‐wide. This study seeks to explore new parallelization strategies for the Epsilon‐Dominance Nondominated Sorted Genetic Algorithm‐II that compare standard Master‐Slave and multiple population parallelization approaches. Our analysis focuses on enhancing the efficiency of evolutionary multiobjective optimization by (1) using convergence based dynamic topologies and (2) enhancing search progress using archive‐based migration strategies. The long‐term goal of this research is to develop parallelization strategies that minimize processor population sizes and communication times while maintaining a proper load balance to achieve optimal speedups. Detailed results of the analysis will be available at the time of the conference.

back to top

SURFACE WATER SYSTEMS APPLICATIONS

Select this Article		Optimized Pond Design for Water Quality Improvement in an Upland Agricultural Basin William E. Gillespie and John W. Nicklow, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)123 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The potential exists for structural best management practices (BMPs) to be improved by coupling simulation and optimization techniques. This project sought to improve the nutrient trapping ability of a retention pond design by linking a BMP simulation model with a heuristic search algorithm. Hydrologic data from a typical agricultural basin is used to run the Integrated Design and Evaluation Assessment of Loadings (IDEAL) model. The IDEAL model is linked with a genetic algorithm to find the principle outlet elevation and outlet diameter that provides the highest level of removal efficiency. The outlet elevation specified by the search algorithm should provide greater nutrient removal over conventional design methods. Various scenarios are run to test the ability of the approach. Results from those trials demonstrate the capablitiy of the model to improve BMP efficiency.

Select this Article		Improvement of Water Network Reliability: A Conflict Resolution Approach Mohammad Karamouz, F. ASCE, Ali Moridi, and Sara Nazif ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)124 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A water distribution system is an interconnected collection of storage tanks, pipes, and hydraulic control elements (e.g. pumps, valves, regulators) delivering water to the consumers in prescribed quantities and at desired pressures. Reliability analysis of a water distribution system is concerned with measuring its ability to meet consumers' demands in terms of quantity and quality, under normal and low flow conditions. This paper presents an approach to optimal operation of water networks in order to increase reliability by pressure management and adding pipes between nodes in the network. As the decision variables have several attributes, the utility of them could be used by the decision makers in form of Nash products. The developed methodology is used by combination of the Genetic Algorithms (GA) and the Artificial Neural Networks (ANN). Cost of piping, amount of leakage and water network reliability are considered in the objective function of the model. In the proposed methodology, the results of the EPANET hydraulic simulation model are used to train the ANNs based simulation model. This model is then linked to the GA based optimization model to develop the optimized piping extensions and pressure in each node. The proposed model is applied to a hypothetical water distribution network but it can be used in real world problems.

Select this Article		A Hybrid Model Tree (MT) — Genetic Algorithm (GA) Scheme for Toxic Cyanobacteria Predictions in Lake Kinneret Avi Ostfeld, M. ASCE, Ariel Tubaltzev, Meir Rom, and Lea Kronaveter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)125 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a hybrid model tree (MT) — genetic algorithm (GA) scheme for toxic Cyanobacteria predictions in Lake Kinneret. Lake Kinneret (the Sea of Galilee) is the most important surface water resource in Israel providing approximately 35% of its annual drinking water, a proportion that is constantly increasing. For more than 30 years there have been no major problems with respect to the water quality of the lake. However, the appearance of toxic Cyanobacteria blooms in 1994 suggests that the future water quality of the lake might be at risk. A full physical understanding of the reasons for the toxic Cyanobacteria blooms is lacking. This study suggests a data driven modeling approach, relying on the vast existing data base of the lake, to explore the possible major factors causing the toxic Cyanobacteria to bloom, and to predict their possible appearance.

Select this Article		Interactive Educational Module to Enhance Understanding of Genetic Algorithms in Surface Water Resources Systems Analysis Talaat El Gamel and Laura J. Harrell, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)126 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An educational module has been developed to introduce graduate‐level students to genetic algorithms and their applications in surface water systems analysis. The module includes a user‐friendly graphical user interface that is used to select genetic algorithm heuristics and parameters and explore their effect on the analysis of an irrigation canal network management problem. The simulation model for the canal network is an unsteady flow model that predicts the hydraulic response in the network to changes in boundary conditions and internal sluice gate operations, as well as the irrigation demands in the areas served by the network. This model is incorporated into a genetic algorithm‐based search framework to find efficient strategies for scheduling gate operations and boundary conditions that minimize the amount of water consumed while satisfying constraints throughout the network (related to flooding, water shortages, stability of gates, etc.) over a period of time. This module has been developed primarily for use in graduate level water resources systems analysis courses, and is intended to help students visualize and understand the effects of different GA operators, parameters and constraint‐handling techniques on the search process and the solution quality.

back to top

AQUIFER PARAMETERS AND INVERSE MODELING

Select this Article		Aquifer Heterogeneity Estimation and Uncertainty Analysis Using a Multi‐Parameterization Method Xiaobao Li and Frank T. C. Tsai, A. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)127 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Understanding of subsurface heterogeneity, e.g., hydraulic conductivity, is inherently difficult in that natural heterogeneity and processes are extremely complex and the available data are limited. Although the parameter structure error in groundwater modeling has been assessed with one parameterization method (zonation or interpolation), with limited information many parameterization methods may interpret the same data satisfactorily. To cope with the non‐uniqueness problem of parameterization, we develop a Bayesian multi‐parameterization (BMP) method to integrate multiple parameterization methods in a Bayesian geostatistical framework. Moreover, a generalized parameterization (GP) method is adopted to estimate the highly complex spatial distribution of parameter heterogeneity. In this study, we combine BMP and GP as a multi‐GP method to better represent the heterogeneity and reduce the model prediction uncertainty. The BMP with GP approach avoids overconfidence in one type of a single parameterization method. The proposed methodology is conducted in a numerical example where the spatially distributed hydraulic conductivity is estimated. The optimal weighting coefficients embedded in GP are identified through the maximum likelihood estimation (MLE) where the misfits between the observed and calculated groundwater heads are minimized. The conditional means and conditional variances of the estimated hydraulic conductivity distribution are obtained to assess the estimation uncertainty.

Select this Article		Geophysical Data Integration and Conditional Uncertainty Analysis on Hydraulic Conductivity Estimation Asheka Rahman, Frank T. C. Tsai, A. M. ASCE, Christopher D. White, Douglas A. Carlson, and Clinton S. Willson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)128 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Integration of various geophysical data is essential to better understand aquifer heterogeneity. However, data integration is challenging because there are different levels of support between primary and secondary data needed to be correlated in various ways. This study proposes a geostatistical method to integrate the hydraulic conductivity measurements and electrical resistivity data to better estimate the hydraulic conductivity (K) distribution. The K measurements are obtained from the pumping tests and represent the primary data (hard data). The borehole electrical resistivity data from electrical logs are regarded as the secondary data (soft data). The electrical resistivity data is used to infer hydraulic conductivity values through the Archie law and Kozeny‐Carman equation. A pseudo cross‐semivariogram is developed to cope with the resistivity data non‐collocation. Uncertainty in the auto‐semivariograms and pseudo cross‐semivariogram is quantified. The methodology is demonstrated by a real‐world case study where the hydraulic conductivity is estimated in the Upper Chicot aquifer of Southwestern Louisiana. The groundwater responses by the cokriging and cosimulation of hydraulic conductivity are compared using analysis of variance (ANOVA).

Select this Article		Using Hydrologic Tracers as a Risk Assessment Tool in a Karstic Watershed R. W. Gentry, J. McCarthy, A. Layton, L. McKay, and S. Koirala ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)129 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Watershed studies using a variety of observational parameters are being implemented to assess how pathogen indicators migrate through rural watersheds. The objectives of the research are to examine the presence and persistence of Bacteriodes and E. coli in several east Tennessee watersheds through observations made in the main channel. Evaluation of combined surface water and groundwater inputs should be evaluated when considering possible regulatory actions through establishment of total maximum daily loads. Further, correlations between hydrologic parameters, water quality, Bacteriodes, and E. coli. are being evaluated in order to examine watershed processes in the system and determine their behavioral response to watershed practices and hydrologic stresses. The experimental design includes a preliminary synoptic evaluation of the water chemistry and bacteria during baseflow conditions through repeated measurements. Streams are known to gain and lose flow throughout the watershed, with certain areas being in proximity to karst features. Definitive causation of bacteria at baseflow is speculative at this point. Sinkhole topography is hypothesized to play an important role in the occurrence of bacteria in the channel which may provide rapid hydrologic transport to and from the channel on a seasonal basis, although direct observation from sinkholes and springs have not been made at this point in the study. The study will provide a robust dataset for evaluating landuse input functions for hydrologic inputs to the watershed.

Select this Article		Parameter Estimation Using an Artificial Neural Network to Incorporate Multiple Types of Data L. E. Besaw, Donna M. Rizzo, and Paula J. Mouser ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)130 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We apply a modified counterpropagation artificial neural network (ANN) that uses multivariate data to several parameter estimation problems: (1) estimation of small scale Berea sandstone geophysical properties, (2) estimation of apparent conductivity at a leaking landfill using electromagnetic data and (3) estimation of hydraulic conductivity field at a landfill in New York State using pumping test and well log data. The counterpropagation algorithm has been enhanced in this research to allow for spatial interpolation that is comparable to traditional kriging methods. This enhanced ANN is data‐driven, can incorporate large amounts of multiple data types to produce parameter estimates in real‐time and does not require the computation of large covariance matrices associated with traditional geostatistical methods (kriging).

back to top

GROUNDWATER HYDROLOGY AND QUALITY MODELING

Select this Article		Development of Analytical Mass Transport Model for the Pollutant Migration in the Subsurface Environment M. Mahadevaswamy, M. Pavithra, and B. M. Sadashiva Murthy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)131 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract To facilitate the predictions of movement and behavior of chemicals, a one‐dimensional analytical model has been developed to predict the solute transport through the unsaturated soil zone. The characteristics feature of this model is that it takes into account the influence of various processes like adsorption, leaching, volatilization, degradation, and plant uptake simultaneously. This could be achieved by introducing a common rate constant term called as total elimination rate, which is the summation of rate constants derived from the degradation, leaching, volatilization and plant uptake processes. It is this feature of the model that sets it apart and excels from that of conventional model or process specific models or site‐specific models, which tends to be expensive, time consuming, and data exhaustive. The application of the developed model has been illustrated by considering the agricultural sub soil environment. The breakthrough curves for concentration versus time and depth were generated for nitrates and phosphates and used to determine the input parameters for the developed analytical transport model.

Select this Article		Transport of Selected Contaminants in Recycled Water through a Hawaii Soil S. K. Mohanty, M. Snehota, and C. Ray ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)132 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Leaching behavior of seven organic contaminants, including lindane, atrazine, N‐nitrosodimethylamine (NDMA), estrone, 17Beta‐estradiol, octylphenol, and nonylphenol, found in the wastewater of a treatment plant in Honolulu were evaluated for leaching in an Oxisoil (a red soil with high iron oxide content) of Oahu using both batch sorption and packed soil column experiments. Soils from two depths (0.6 m and 3.9 m) were used for the study. Two column leaching experiments were conducted using a solution of the contaminants in an artificially created ground water (deionized water with small concentrations of calcium chloride) and treated wastewater. The breakthrough curves obtained from the column experiments were used in inverse numerical modeling (HYDRUS 1D) to obtain the transport parameters for the column experiments. Sorption characteristics of each compound were obtained through batch sorption studies with different controlling parameters such as pH, ionic strength, and organic carbon content. The results of the experiments indicated that NDMA possessed the maximum potential to leach through the tested soil. Both atrazine and lindane showed moderate leaching properties. The estrogenic and the phenolic compounds were strongly adsorbed to the soil and were retained in the columns. Transport parameters obtained from the column study will be applied to the field setting to determine the arrival time and extent of contamination of ground water where widespread irrigation with wastewater over potable water aquifers to be practiced. Increases in leaching under different controlling parameters (pH, ionic strength, etc.) will also provide additional information about leaching potential.

Select this Article		A Stochastic Streamtube Model for NAPL Transport in Heterogeneous Media T. P. Chan and Rao S. Govindaraju ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)133 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Remediation schemes for contaminated sites are often evaluated to assess their potential for source zone reduction of mass, or treatment of the contaminant between the source and a control plane (CP) to achieve regulatory limits. In this study, we utilize a stochastic stream‐tube model to explain the behavior of breakthrough curves (BTCs) across a CP. At the local‐scale, mass dissolution at the source is combined with an advection model with first‐order decay for the dissolved plume. Field‐scale averaging is then employed to account for spatial variation in mass within the source zone, and variation in the velocity field. Under the assumption of instantaneous mass transfer from the source to the moving liquid, semi‐analytical expressions for the BTC and temporal moments are developed, followed by derivation of expressions for effective velocity, dispersion, and degradation coefficients using the method of moments. Modified definitions of effective parameters are presented for degrading solutes to account for the normalization constant (zero‐th moment) that keeps changing with time or distance to the CP. Implications of model results on estimating cleanup times and fulfillment of regulatory limits are discussed.

Select this Article		Fractured Modeling Approaches in Arbuckle‐Simpson Aquifer A. K. Tyagi, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)134 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents assessment of groundwater resources in Arbuckle‐Simpson aquifer located in Southern Oklahoma. This research paper evaluates the response of the aquifer to natural recharge, springs, and stream discharges, and withdrawal of groundwater from pumping wells in the aquifer. Currently, the aquifer is underutilized and the Oklahoma Legislature would like to assess the result of increased pumpage from this aquifer. The demand of groundwater from this aquifer is anticipated to increase over the next thirty years.

back to top

GROUNDWATER MANAGEMENT

Select this Article		Optimal Groundwater Management Using Empirical Orthogonal Functions James McPhee and William W.‐G. Yeh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)135 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This research investigates the applicability of model reduction, through empirical orthogonal functions (EOF's) and the Galerkin projection, to groundwater management. In the past, groundwater models have been coupled with optimization algorithms to solve parameter estimation and groundwater management problems. The solution of a groundwater management problem generally involves finding a set of pumping/recharge rates that maximizes some measure of the system performance while satisfying a set of constraints on groundwater heads, velocities or solute concentrations. Solution of the management problem with an optimization algorithm requires repeated calls to a numerical simulation model for objective function and gradient evaluations. In many practical applications the simulation model may include thousands of nodes, and extensive solution times required to run the simulation model may prohibit the applicability of simulation‐optimization schemes to large‐scale problems or to real‐time decision support. The use of a reduced model for simulation permits a dramatic decrease in running times when the EOF's have been computed in advance. As a result, when quick answers are required, fast execution of the reduced model makes it possible to apply simulation and optimization, such as real‐time group decision‐making and conflict resolution. Results from the proposed methodology are compared with results obtained with the original groundwater model, in order to assess the effect of the necessary loss of accuracy that stems from using the reduced model over the solution of the management problem for a real‐world case study.

Select this Article		Varied Solutions to Groundwater Problems: Four Case Histories Donald J. Novak, P.E., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)136 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The time has passed when witching, drilling a test hole and finding good formation is adequate to site a new well for a drinking water supply. Quality, quantity, and aquifer management must all be thoroughly evaluated when developing or expanding a groundwater supply. Four case histories are described that do just that. New appropriations for groundwater rights in the Garden City, Kansas area have been frozen for several years. A public‐private partnership between Wheatland Electric Cooperative and the City of Garden City was used to solve local problems with water rights and water quality. Wheatland converted existing industrial water rights and constructed a 6.5‐MGD reverse osmosis blended treatment plant to sell water to potential customers. Several customers are now being served and there has been interest by several industries in buying water. Economic development in the Garden City community is back on track because of the availability of good quality groundwater, properly managed. The water levels in the Equus Beds, a prolific groundwater supply providing the majority of water for Wichita, Kansas, have been dropping for several years. This drop in groundwater levels was causing saline water to be drawn into the aquifer from the north and southwest, causing deteriorating water quality. Several alternatives were evaluated, including aquifer storage and recovery (ASR). Several ASR alternatives were evaluated in this multi‐year demonstration project, to determine the best method to store excess flows from the Little Arkansas River. It is planned to store and recover both surface water from induced infiltration and treated surface water, thus blocking chlorides from local supplies. Wichita can continue to develop because of an adequate quantity of good quality groundwater, properly managed for the City and their neighbors. Lake Havasu City, Arizona has provided water to its citizens since it was incorporated in 1973. Their groundwater supply exceeded secondary drinking water standards for manganese, and the taps of water users often flowed black. Citizens voted to develop a new water treatment plant to remove manganese and arsenic, a constituent also found that exceeded drinking water standards. The nation's first manganese removal plant to use biological filtration was built and can provide up to 26‐MGD of good quality water. This City of 50,000 can continue their rapid growth partially because they now have good quality water with adequate quantity for many years. Union County, Arkansas had realized for many years that their groundwater supply, the Sparta Aquifer, was rapidly dewatering. A County Groundwater Conservation District was established and a means of financing formulated. The final master plan recommended using surface water from the nearby Ouachita River to supply local industrial users with process and cooling water, leaving the Sparta aquifer for municipal and domestic supply. A countywide sales tax, voted to sunset in seven years, helped pay for construction. Union County now owns and operates a river intake, pretreatment facility, pumping station, and many miles of large water lines. Management of their water resources has saved both Union County and the Sparta from extinction.

back to top

GROUNDWATER MANAGEMENT UNDER UNCERTAINTY

Select this Article		Optimizing Groundwater Remediation Designs under Uncertainty Using Dynamic Surrogate Models Shengquan Yan and Barbara Minsker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)137 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Computational cost is a critical issue for large‐scale water resource optimization problems that often involve time‐consuming simulation models. This issue is compounded when optimizing under uncertainty, since Monte Carlo simulations are often required to evaluate objective function values over multiple parameter realizations. In order to improve computational efficiency, we propose a dynamic surrogate modeling approach to approximate and replace the time‐consuming numerical models within a noisy genetic algorithm (GA) optimization framework. The surrogates are trained to predict the distribution of the objectives online, using Monte Carlo simulation results created during the GA run. The surrogates are then adaptively updated to improve their prediction performance and correct the GA's convergence as the search progresses. Latin Hypercube sampling method is used to efficiently sample parameters for the Monte Carlo simulation and the sampling results are archived so that the estimation of the objective function distributions is progressively improved. The GA is modified to incorporate hypothesis tests to produce reliable solutions. The method is applied to a hypothetical groundwater remediation design case study, where the primary source of uncertainty stems from hydraulic conductivity values in the aquifers. Our preliminary results show that the technique can lead to reliable and cost‐effective solutions with significantly less computational effort.

Select this Article		Impact of Conditioning on Robust Remediation Design Olufemi Adaramola and Teresa B. Culver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)138 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Uncertainties in input parameters, such as hydraulic conductivities may result in inconsistencies between simulated and observed groundwater flow and transport data. If a groundwater management model for aquifer remediation design is based upon incorrectly estimated flow and transport parameter data, non‐optimal remediation policies may result. To improve upon deterministic management, which is based on a single calibrated input parameter set, previous studies have developed robust optimization models for remediation design. Robust optimization searches for a remediation policy that is likely to perform well over the range of conditions that might be observed in the field. The range of conditions is simulated through generation of multiple realizations of unconditional random fields of the uncertain parameters. These robust optimization studies have explored the relative impact of the degree of uncertainty in various input parameters on the robust management decisions. This study expands upon previous work through incorporation of random fields conditioned on localized field observations. The importance of conditioning on both the final remediation design and on the conclusions about the overall impact of parameter uncertainty is explored by comparison to robust optimization using unconditional random fields and by varying the number of data points utilized for conditioning.

back to top

GROUNDWATER REMEDIATION

Select this Article		Effect of Heterogeneity Correlation Scale on Pump‐and‐Treat Remediation Design G. Güngör‐Demirci and A. Aksoy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)139 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Pump‐and‐treat (P&T) remediation is a commonly used technology for the cleanup of contaminated groundwater. The long remediation time, high capital and operational costs are the most important problems associated with these systems. One of the determinants that affect the remediation design and its outcome is the spatial heterogeneity in the hydraulic conductivity (K) field. In this study, the effect of correlation scale (length) (lambda) of the heterogeneous K‐field on P&T remediation design and costs was investigated. For this purpose, several synthetic K‐fields of similar means and variances (sigma²) but different lambdas were generated using a random field generator. Simulation‐optimization approach was used in order to conduct the study. For this purpose, BIO2D‐KE linked with a genetic algorithm library was used. Runs were conducted in order to determine the best pumping policies and costs for the heterogeneous fields. According to the initial results, lambda of the spatial variation in K impacted P&T remediation design and costs. The number of wells, pumping rates, and costs of remediation varied for different lambdas. This outcome was more pronounced for higher sigma² of the spatially variable K‐field.

Select this Article		In‐Situ Bioremediation of Contaminated Groundwater Using Artificial Neural Network Ram Kailash Prasad and Shashi Mathur ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)140 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A methodology has been developed in this study to optimize pumping (extraction/injection) rates in in‐situ bioremediation system design with the aid of Artificial Neural Network (ANN). The equation governing in‐situ bioremediation system consists of the flow equation and the equation of solute transport coupled with biodegradation kinetics, that results into a highly non linear system of equations. Consequently, the computational effort involved is a significant problem in the design of bioremediation systems. In this study, the computational burden is managed within practical time frame by replacing the BIOPLUME III simulation model with an ANN model. Artificial Neural Network has been considered to be a universal function approximator that generates fast solutions in real time. Besides this, the search for the optimal pumping pattern is directed by a simple genetic algorithm in this study. The results show that the costs involved in the proposed management solution is consistent with those resulting from other non traditional optimization techniques which use embedded bioremediation models. However, it has been observed that one can achieve considerable decrease in the number of simulations involved using the ANN approach.

Select this Article		Exact Analytical Solution to the One‐Dimensional Advective‐Dispersive Equation with a Decaying Source Term Gustavious Paul Williams, M. ASCE and David Tomasko ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)141 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an exact analytical solution of one‐dimensional transport of a contaminant undergoing advection, dispersion, sorption, and first‐order decay, subject to unique boundary conditions, a first‐order decaying contaminant concentration in time at the source with a constant concentration at infinity. This exact solution provides a method to study a new area of physical processes and to evaluate approximate methods and models that have been developed to analyze these problems. Recently two fields have developed interest in modeling physical processes that are best conceptualized using a decaying source boundary condition. These two fields are long‐term modeling of recalcitrant non‐aqueous phase liquid (NAPL) spills and radioactive waste disposal. Both of which can be approximated using a decaying source term. This paper briefly introduces some general field transport problems that can conceptually be described using a decaying source boundary condition. The paper then describes the governing equations, boundary and initial conditions, and the solution techniques used to develop the analytical solution. Next the analytic solution is provided and discussed along with some example cases. The results of the exact analytical solution are compared to another similar solution from the literature.

Select this Article		A Multi‐Objective Water Quality Wetland to Complement Phytoremediation of Contaminated Groundwater Charles Ikenberry, P.E., Joan Darling, Ph.D., Chris Talley, John Williams, Jeff McPeak, Steve Gilmore, Don Steck, Lorraine LaFreniere, Ph.D., and Tony Ruhge ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)142 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the planning and design of a constructed wetland that is part of a groundwater remediation project in Murdock, Nebraska. The wetland design attempts to optimize the carbon tetrachloride remediation process while protecting adjacent properties from flooding and channel instability, enhancing wildlife habitat, and creating recreational and educational opportunities for the citizens of Murdock. Features were incorporated into the wetland design that would encourage volatilization of carbon tetrachloride during the non‐growing season, as well as phytovolatilization and rhizodegradation during the growing season. As with any constructed wetland, control of the hydrologic regime was an important consideration for water quality improvement, habitat development, and maintenance. The water level is controlled by adjustable stop‐logs mounted in a concrete outlet structure. Although typical wetland restoration sites are designed to safely pass 25‐year storm events, this outlet structure was sized to safely pass a 100‐year storm event. The interpretive trail that winds around the wetland offers opportunities for recreational and educational activities. The wetland is also accessible for water quality monitoring and further scientific investigations. Lessons learned in the design and construction of this polishing wetland should provide valuable insights for future efforts to complement phytoremediation with constructed wetlands.

back to top

GROUNDWATER/SURFACE WATER INTERACTION

Select this Article		The Life Cycle of Vernal Pools: Hydrologic Principles Hugo A. Loáiciga ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)143 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper reviews the hydrologic principles governing the life or flooding‐drying cycle of vernal pools. A quantitative method for describing the ponding hydrograph in a vernal pool formed by rainfall or by artificial flooding is proposed. This method can be used for predicting the flooding‐drying phases of a vernal pool, and also to achieve desired ponding hydrograph in vernal‐pool restoration work.

Select this Article		Modeling of Soil Hydraulic Processes and Base Flow in Flanders M. H. Rubarenzya, A. M. ASCE, P. Willems, J. Feyen, and J. Berlamont ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)144 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents findings from an investigation into catchment hydrological response to changing stimuli, including land use change, climate change, and river valley rewetting. It outlines the central role of groundwater modeling in the development of a physically based, fully distributed catchment model, which role was as a consequence of the stream flow composition. The paper also examines the influence of the catchment's hydraulic characteristics on the discharge. The study area was the Grote Nete catchment, located in the northeast of Belgium. Numerical digital filtration established that base flow constitutes the dominant stream flow of the river network, accounting for over 60% of the flow, followed by interflow with 25%. It was thus, considered paramount that these flow components be modeled accurately. The paper also highlights two issues that were taken into consideration when characterizing the catchment model. Firstly, the experimental procedures for measuring the soil hydraulic characteristics are difficult and not very reliable. Secondly, the use of pedotransfer functions to derive the characteristics from more easily measurable characterizing properties of the soil is equally as unreliable. The Averjanov method was used for the model. This method contains an exponent, whose value had a direct influence on the percolation rate in the soil and thereby influenced the actual evaporation rate. The MIKE SHE model code was adopted to model the temporal and spatial variability of soils. In testing the model hypothesis, the research made use of discharge data. For implementing a multi‐criteria calibration protocol, a tool was sought that incorporates a recursive digital filter for exponential recessions to split total rainfall‐runoff discharges into its three component sub‐flows, and is able to determine the recession constants for each component. WETSPRO, a tool for time series analysis, was adopted. The catchment model is now being used to study trends of anthropogenic changes on catchment hydrology.

back to top

LONG‐TERM MONITORING

Select this Article		Bayesian Statistics‐Based Procedure for the Groundwater Long‐Term Monitoring Temporal Optimization Problem Yuanhai Li and Amy B. Chan Hilton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)145 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Groundwater long‐term monitoring (LTM) is required for groundwater remediation projects to assess compliance of active remedial systems and natural attenuation sites where groundwater contamination is still present. LTM can be costly given the large number of sampling locations, frequency of monitoring, and number of constituents monitored at given site. This study uses a Bayesian statistics‐based methodology to optimize the scheduling of groundwater long‐term monitoring. This method does not rely on pollutant simulated transport models. The technique combines information from different sets of observations over multiple sampling periods with spatial sampling optimization by ant colony optimization algorithm. Instead of binary results (0/1), this methodology will suggest future monitoring schedule of each individual monitoring well on fuzzy probabilistic scale (0–1) and thus facilitating its inclusion into risk assessment procedures.

Select this Article		Optimizing LTM Networks: Applying GTS at Tinker AFB Kirk Cameron ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)146 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper adds an important case study to the long‐term monitoring (LTM) optimization literature and discusses some of the advantages, as well as limitations, of the Geostatistical Temporal‐Spatial (GTS) algorithm and software. Application of GTS at Tinker AFB demonstrates that the basic optimization approach now built into GTS can offer substantial cost‐savings in LTM costs, and that the re‐designed algorithm offers flexibility in its applicability to challenging site environments, and greater simplicity for non‐expert users.

Select this Article		Computational Scaling Analysis of Multiobjective Evolutionary Algorithms in Long‐Term Groundwater Monitoring Applications Joshua B. Kollat and Patrick M. Reed ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)147 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This study contributes a detailed assessment of how increased problem sizes impact the computational complexity of using multiple objective evolutionary algorithms (MOEAs) for long‐term groundwater monitoring (LTM) applications. Problem size in this study is measured in terms of the number of design decision variables being considered. Computational complexity (or scaling) can be defined as a measure of how increased problem sizes impact the growth rate of the average number of design evaluations required by an MOEA to successfully solve an application. Building on a recent comparative analyses of MOEA effectiveness, this study characterizes the computational complexities of the Epsilon‐Dominance Non‐Dominated Sorted Genetic Algorithm II (ϵ‐NSGAII) developed by the authors. This algorithm has proved to be more efficient and reliable relative to other state‐of‐the‐art MOEAs. This study's computational scaling analysis is based on a suite of long‐term groundwater monitoring (LTM) test cases formulated to test a range of problem sizes. The purpose of this study is to provide guidance on the current computational complexity of MOEAs to clarify future research paths that will allow them to solve larger water resources applications efficiently and reliably.

back to top

PROBABILISTIC GROUNDWATER MODELING

Select this Article		Vertical Flow Aggregation in the Vadose Zone with Spatial‐ and Cross‐Correlated Hydraulic Properties Antonella Sciortino and Feike J. Leij ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)148 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Knowledge of hydrological data at or near the soil surface of “large” areas — a field, catchment or watershed — is of considerable interest for the management of surface and subsurface water resources and environmental research dealing with mass transfer at the earth‐atmosphere interface. The gap between the local scale for conceptual modeling and observations, and the much larger application and validation scale is bridged with aggregation procedures. Especially for the vadose zone, aggregation is subject to uncertainty due to cross‐ and auto‐correlation of hydraulic properties and nonlinear flow. This study compares a priori aggregation of hydraulic properties with a benchmark a posteriori aggregation of simulation results. Monte Carlo simulations of evaporation were conducted for a synthetic watershed. First, probability density functions (pdf's) and cross‐correlations of hydraulic parameters were established from a set of 126 retention curves and saturated hydraulic conductivities from the UNSODA database. Second, random fields of two hydraulic parameters were generated with imposed auto‐ and cross‐correlation. Third, evaporation was simulated using a stream tube model. Fourth, a posteriori and a priori aggregation were employed to estimate water content and moisture fluxes for different field scales and to quantify the behavior of field‐scale mean and variance. A posteriori aggregation yielded the correct mean and a realistic decrease in variance with increasing field scale. On the other hand, a priori aggregation resulted in erratic predictions of the mean and variance of the evaporation flux at the field scale. The cross‐correlation between hydraulic parameters enhanced clusters with low or high water contents and evaporation fluxes.

Select this Article		A Statistical Study of the Hydrological Character of the Edwards Aquifer Gustavious Paul Williams, M. ASCE and David Tomaskos ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)149 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Edwards Aquifer is located in south‐central Texas with a length of about 180 miles, and varying width from 5 to 40 miles. It is one of the most permeable and productive artesian limestone aquifers in the United States and supplies drinking water to more than 1.5 million people in San Antonio and the Austin‐San Antonio corridor. Water from the aquifer is vital to the agricultural and light industrial economy of the region. Discharge from the aquifer provides water to many springs in the area, including two large springs, San Marocs and Comal Springs. Flows from the these springs provide water for the tourist and recreation industry, critical habitat for several endangered species and appropriated water use downstream for the Gulf Coastal Plain and the San Antonio Bay ecosystem. A major storm occurred in south‐central Texas on October 17, 1998, through October 19, 1998 with most of the precipitation falling within the first 24 hours. The storm had two main centers of rainfall; one with 30 inches of rainfall and a second with about 22 inches of rainfall. This storm provided a unique stress on the Edwards Aquifer that allowed us to study the correlation between the surface water and groundwater systems and infer information about recharge, storage, and flow in the Aquifer. The study found that the initial response of river and stream flow to the precipitation event was very rapid and produced sharp peaks in flow with fast recession curves. Well and spring response was slower, with the well response times significantly longer than those of the springs. The data shows interesting correlations between the surface and ground water systems that are indicative of aquifer characteristics and help provide insight for future management decisions.

Select this Article		Kernel‐Based Sparse Bayesian Learning for Interpolating Spatial Data Shivam Tripathi and Rao S. Govindaraju ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)150 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Interpolation of spatial variables is of primary importance for hydrogeological applications. Various approaches have been considered in geostatistical literature to address this issue. However, most traditional interpolation methods, including inverse distance weighting, standard kriging and radial basis functions techniques have various limitations. Kernel‐based sparse bayesian learning, which has received much attention in the context of regression and classification, can provide a probabilistic framework for spatial interpolation. This study reports the use of the theory of relevance vector machine (RVM), a particular specialization of bayesian learning, for interpolating spatial variables at unknown locations. An important practical question dealing with the selection of the kernel function parameters in the design of RVMs is addressed here. The results indicate that the proposed method of selecting kernel parameters can translate into improved performance of RVMs.

back to top

TUTORIAL: FUNCTION APPROXIMATION OPTIMIZATION FOR UNCERTAINTY IN GROUNDWATER APPLICATIONS

Select this Article		Tutorial on Function Approximation Optimization for Computationally Expensive Nonlinear Models Including Applications to Uncertainty Analysis and to Groundwater Transport Christine A. Shoemaker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)151 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Optimization is useful in water resource and environmental analysis both for design of remediation plans and for calibration. Optimization is used in calibration for selecting the best parameters for models based on comparison of model results to historical data. The main types of nonlinear optimization in use are (1) derivative based algorithms for finding local optima and (2) heuristic methods like genetic algorithms or simulated annealing for global optimization. Function Approximation is a new approach that differs from both derivative based and heuristic evolutionary optimization. Function Approximation is designed for optimization of computationally expensive functions like simulation models for which it is not feasible to run the model a large number of times. In this tutorial we will discuss new methodology to solve problems involving computationally expensive functions, i.e. cases where the times involved in the model simulation prevent a large number (e.g. thousands) of simulations in order to find the best answer.

back to top

TUTORIAL: LONG‐TERM MONITORING

Select this Article		Long‐Term Monitoring Optimization Using MAROS Mindy Vanderford, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)152 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The AFCEE Monitoring and Remediation Optimization System (MAROS) Software is a Microsoft Access database application developed to assist users with groundwater data trend analysis and long term monitoring optimization at contaminated groundwater sites. MAROS is a collection of statistical and data visualization tools in one software package designed to aid stakeholders in evaluating and developing efficient long‐term groundwater monitoring programs. The MAROS methodology is designed to organize large quantities of site data and focus analysis to reveal underlying trends in the data. By reviewing several lines of evidence on plume stability and predictability, the user can optimize a groundwater monitoring network both temporally and spatially while maintaining adequate delineation of the plume. The MAROS software training presents an introduction to the MAROS methodology and software application. The tutorial program is intended to provide users with the basic skills to begin site analysis and to understand the application of the methodology to various regulatory contexts.

back to top

ACOUSTIC DOPPLER PROFILING APPLICATIONS

Select this Article		Recent Applications of Hydroacoustic‐Based Field Flow Measurements in Understanding the Hydraulics of Water Control Structures Matahel Ansar, Zhiming Chen, and Juan Gonzalez‐Castro ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)153 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hydroacoustic‐based field flow measurements have been applied at the South Florida Water Management District (SFWMD) for the last ten years for rating validation and calibration of water control structures, such as spillways, weirs, pumps and culverts. This paper summarizes recent applications of these types of measurements in calibrating flow rating equations at hydraulic structures maintained and operated by SFWMD for real‐time flow monitoring. Selected recent research findings on complex physical processes related to the hydraulics of flow through water control structures are then discussed. The findings include improved rating equations for free and submerged orifice flow at radial gate spillways.

Select this Article		Determining Hydraulic Conditions for Holding Areas of Large Predatory Fish within the Tracy Fish Collection Facility K. W. Frizell and R. Bark ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)154 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hydraulic conditions within Reclamation's Tracy Fish Collection Facility (TFCF) were measured using a Nortek BoogieDopp acoustic Doppler current profiler. This instrument is essentially a modified AquaDopp profiler, mounted on the underside of a boogie board, using wireless modem communication with a Pocket PC for control and data collection. These data were collected to support on‐going research to track and locate holding areas for large predatory fish (striped bass) within the confines of the facility. The velocity profile data at and near these locations help biologists and engineers better understand the types of flow fields that should be avoided within structures if the goal is to pass fish most expeditiously into a holding facility. The BoogieDopp collects velocity profiles in‐line with the axis of the profiler through the depth of the water column. When measured simultaneously with sonic locating of tagged fish, the researchers are given a clearer picture of the types of flow conditions that allow predatory species to hold and feed on other unsuspecting fish passing through the facility. The BoogieDopp's remote operation and ability to collect a velocity profile rather than just a point velocity promotes a much better understanding into the behavior of these predatory fish.

Select this Article		Characterizing a December 2005 Density Current Event in the Chicago River, Chicago, Illinois Carlos M. García, P. Ryan Jackson, Kevin A. Oberg, Kevin K. Johnson, and Marcelo H. García ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)155 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract During the winter months, the Chicago River in Chicago, Illinois is subject to bi‐directional flows, and density currents are thought to be responsible for these flow variations. This paper presents detailed field measurements using three acoustic Doppler current profiler instruments and simultaneous water‐quality measurements made during December 2005. Observations indicate that the formation of density currents within the Chicago River and density differences are mostly due to salinity differences between the North Branch and the main stem of the Chicago River, whereas temperature difference does not appreciably affect the creation of density currents. Sources of higher water temperature, conductivity, and salinity values should be addressed in future studies.

Select this Article		Hydraulic Capacity Assessment of a Tidally‐Affected Reach of the Loxahatchee River by Direct Hydroacoustic Flow Measurements Juan A. González‐Castro, Rodrigo Musalem, and Orlin Kellman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)156 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Loxahatchee River is a small stream that discharges into the Loxahatchee Estuary on the eastern side of South Florida. The river runs through an environmentally sensitive area where the combination of low flows and tidal influence has been subjecting the coastal ecosystem to harmful salinity concentrations. This paper summarizes the bankfull channel capacity analysis of a river reach subject to tidal influence, conducted in support to the development of the Loxahatchee River Restoration Plan (LRRDP). The analysis is based on direct measurements of discharge and stage at four stations between river mile 11.2 and river mile 14.5. The discharge measurements were made with a four‐transducer, 2400‐kHz Acoustic Doppler Current Profiler (ADCP) with Janus configuration during low flow and high tide amplitude conditions for about half a tidal cycle. Hydraulic analysis of the stage‐discharge relations developed from the data collected at each station during this period allowed us to establish that for low flows during high‐range tides, the tidal effect propagates upstream up to river mile 12. As a result, the bankfull channel capacity at all stations downstream from this river station is affected by both the tidal range and the base flow from inland. The field data collected at river mile 11.2 shows that, at high tide, the bankfull channel capacity at this station is about 15 percent less than that during low tide.

back to top

ACOUSTIC DOPPLER VELOCIMETRY APPLICATIONS

Select this Article		Turbulence Observations in Cobble‐Bed Rivers Mark C. Stone, Rollin H. Hotchkiss, and Ryan R. Morrison ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)157 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Improving descriptions of natural stream flow fields is a critical step in restoring aquatic ecosystems. Current methods used for evaluating aquatic habitat rely on simplified representations of the flow field. These methods can be improved by incorporating important spatial and temporal flow field variations and more advanced habitat metrics. However, knowledge of velocity and turbulence distributions in natural streams is limited to laboratory derived empirical equations. Further, only limited experiments have been conducted in natural streams. The objectives of this research were to evaluate the adequacy of existing empirical relationships for describing natural stream flow fields and to investigate spatial distributions of flow variables. In this research, acoustic Doppler velocimeter (ADV) measurements were conducted at the reach scale (approximately 5 stream widths) in two cobble‐bed streams. The measurements encompassed riffle, pool, and run stream units. The results showed that velocity distributions were adequately predicted with the log‐law for all stream units and transverse locations. However, empirical turbulence intensity and turbulent kinetic energy equations inadequately described measured values. This was likely due to turbulence generation from stream banks, bedforms, obstructions, and other stream features.

Select this Article		ADV Point Measurements within Rapids of the Colorado River in Grand Canyon Christopher S. Magirl, Peter G. Griffiths, and Robert H. Webb ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)158 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Rapids on the Colorado River in Grand Canyon attract over 20,000 white‐water enthusiasts a year and are considered one of the premiere collections of rapids in North America. While this collection of rapids is an important recreational resource, relatively little is known of the specific hydraulics of individual rapids. Flow measurements are occasionally made in the low‐velocity reaches between rapids, but the turbulent and dangerous nature of rapids makes in‐situ data collection challenging. The present study measured hydraulics within a small rapid in Grand Canyon as well as an alluvial reach of the Colorado River in Glen Canyon using a Sontek Argonaut acoustic Doppler velocimeter (ADV)². The ADV was mounted near the center‐front of a motor‐powered 19‐foot J‐snout boat; the instrument sample volume was located 80 cm below the surface. The quality of the measurements was best in the slower water above the rapid and in Glen Canyon. Waves, aeration, and high‐velocity water rendered specific measurements in the core of the rapid difficult as the ADV instrument could only measure velocities less than about 3.0 m/s. Nonetheless, velocity, bathymetry, and water‐surface maps were constructed for the rapid and the reach in Glen Canyon. The compiled data sets can be used for predicting the erosion potential of debris fans forming the rapid and the development of numerical models to better characterize rapids.

Select this Article		Turbulence Characteristics of Flow in a Culvert with Sloped‐Weir Baffles Ryan R. Morrison, David Thurman, Alex F. Compton, Rollin H. Hotchkiss, and Alex R. Horner‐Devine ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)159 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The problem of culverts that block fish from freely moving up and downstream is becoming a critical environmental issue. Agencies often retrofit culverts with baffles to aid in fish passage, but little is known about the detailed flow characteristics within a baffled culvert. During August and September, 2005, fine‐scaled measurements were taken at the Skookumchuck hatchery near Tenino, WA on the flow field inside a 6‐foot diameter corrugated metal culvert fitted with sloped‐weir baffles. The culvert was 40 feet long and set at a 1.14% slope, and the data were collected for flow rates 1.5, 2.0, 3.0, 4.0, and 8.0 cubic feet per second. Flow field measurements were collected using a Sontek acoustic Doppler velocimeter at 50 Hz. Preliminary data were used to understand the turbulence characteristics of flow within a culvert fitted with baffles, and to compare the flow field caused by sloped‐weir baffles to experiments of other baffle types recorded in literature. It has been found that the turbulent kinetic energy (TKE) dissipates as the flow moves downstream from a baffle. At flows less than 3.0 cfs, the sloped‐weir baffles cause higher TKE values on the left side of the flow (looking upstream) due to plunging flow. As the flow rate increases, the TKE becomes equal on both sides of the culvert, and are higher on the edges due to shear stress caused by the culvert boundary. The flow is also described using dimensionless discharge, and data from this experiment are compared to dimensionless discharge equations given by previous researchers. This research provides new information on the turbulence characteristics of flows within culverts retrofitted with sloped‐weir baffles, and will be useful in recognizing which areas of the flow field could be too turbulent for fish passage.

Select this Article		Hydrodynamics of Juvenile Salmon Passage in Sloped‐Baffle Culverts David R. Thurman, Alex R. Horner‐Devine, Ryan R. Morrison, Rollin H. Hotchkiss, and Alex F. Compton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)160 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Recent evidence suggests that, although their ultimate destination is the sea, juvenile salmonids also travel upstream to locate more desirable habitat and feeding areas. Since many culverts are impassible to juvenile salmonids, baffle systems are being evaluated that will facilitate greater upstream passage. A culvert test bed facility at Washington Department of Fish and Wildlife Skookumchuck Rearing Facility near Tenino, Washington was built to test fish passage success and study the hydrodynamic regimes induced by the baffles. The study involved installing baffles within a 40 foot long, 6 foot diameter corrugated culvert and recording 3‐D velocities using an Acoustic Doppler Velocimeter (ADV). The purpose of these tests is to describe the hydrodynamics of the baffle flow and to evaluate how different hydraulic conditions may benefit or hinder fish passage. Baffle generated flow structures such as a jet on the low side of the baffle or a roller wave are identified. Using the 3‐D velocity data and surface images, the flow structures are then characterized according to their intensity and size. A scaling equation is analyzed to relate the modification of flow features to the independent study parameters. This paper establishes hydraulic guidance that can help biologists and engineers to improve baffle design and configuration to aid juvenile salmon migration.

back to top

EVALUATION OF ACOUSTIC MEASUREMENT TECHNIQUES

Select this Article		Development of a Simple Loop Method for Correcting Acoustic Doppler Current Profiler Discharge Measurements Biased by Sediment Transport David S. Mueller and Chad R. Wagner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)161 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A negative bias in discharge measurements made with an acoustic Doppler current profiler (ADCP) is attributed to the movement of sediment near the streambed and is an issue widely acknowledged by the scientific community. The integration of a differentially corrected Global Positioning System (DGPS) to track the movement of the ADCP can be used to avoid the systematic bias associated with a moving bed. DGPS systems, however, cannot provide consistently accurate positions because of multipath errors and satellite signal reception problems on waterways with dense tree canopy along the banks, in deep valleys or canyons, and near bridges. An alternative method of correcting for the moving‐bed bias, based on the closure error resulting from a two‐way crossing of the river, is presented. The uncertainty in the mean moving‐bed velocity measured by the loop method is shown to be approximately 0.6 cm/s. Use of this method to correct the measured discharge is evaluated. For the 13 field measurements presented, the loop method resulted in corrected discharges that were within 5 percent of discharges measured utilizing DGPS to compensate for moving‐bed conditions.

Select this Article		Field Evaluation of Shallow‐Water Acoustic Doppler Current Profiler Discharge Measurements Michael S. Rehmel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)162 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In 2004, the U.S. Geological Survey (USGS) Office of Surface Water staff and USGS Water Science employees began testing the StreamPro, an acoustic Doppler current profiler (ADCP) for shallow‐water discharge measurements. Teledyne RD Instruments introduced the StreamPro in December of 2003. The StreamPro is designed to make a “moving boat” discharge measurement in streams with depths between 0.15 and 2 m. If the StreamPro works reliably in these conditions, it will allow for use of ADCPs in a greater number of streams than previously possible. Evaluation sites were chosen to test the StreamPro over a range of conditions. Simultaneous discharge measurements with mechanical and other acoustic meters, along with stable rating curves at established USGS streamflow‐gaging stations, were used for comparisons. The StreamPro measurements ranged in mean velocity from 0.076 to 1.04 m/s and in discharge from 0.083 m³/s to 43.4 m³/s. Tests indicate that discharges measured with the StreamPro compare favorably to the discharges measured with the other meters when the mean channel velocity is greater than 0.25 m/s. When the mean channel velocity is less than 0.25 m/s, the StreamPro discharge measurements for individual transects have greater variability than those StreamPro measurements where the mean channel velocity is greater than 0.25 m/s. Despite this greater variation in individual transects, there is no indication that the StreamPro measured discharges (the mean discharge for all transects) are biased, provided that enough transects are used to determine the mean discharge.

Select this Article		Uncertainties in Discharges Determined from Index‐Velocity Ratings Arthur Schmidt, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)163 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Time‐series data describing the rate of flow of water (discharge), along with a description of the uncertainty in the reported discharges, are essential for most water‐resources analyses, designs, and decision making. Direct measurement of discharge, however, is impractical; thus, most discharge records are developed using empirical ratings to estimate the discharge based on measured water stages. For many streams, however, the stage alone is insufficient to determine the discharge. Advances in hydroacoustics over the past decade have resulted in a family of rating methods that use the velocity measured for a subsection of the flow area (“index velocity”) as a second parameter to estimate the discharge. While different methods have been utilized to incorporate the velocity data into discharge ratings, the method that is becoming widely accepted is the “Index‐velocity method,” in which an empirical rating between the index velocity and the cross‐section mean velocity is developed. Index‐velocity methods are being widely adopted and a few studies have examined the uncertainties in the resulting discharges from a statistical perspective. However, the uncertainties in these ratings have generally been lumped into “goodness‐of‐fit” statistics such as the standard error of regression. This approach precludes estimating the portion of the discharge uncertainty from different sources (e.g., instrument precision, temporal variations in the flow, percentage of the cross section measured, etc.). Without identification of the sources of uncertainty and quantification of their effect on the discharges, selection of instrument precision, number of sampling points, frequency and duration of index‐velocity measurements, frequency and duration of rating measurements, etc. becomes a ‘seat‐of‐the‐pants’ exercise rather than a rational scientific design. This paper presents an overview of potential sources of uncertainty in index‐velocity ratings and demonstrates use of reliability‐analysis methods to synthesize these into an estimate of the uncertainty in the calculated discharges. An example applications to an index‐velocity gauging station illustrates the relative significance of different sources of uncertainty.

Select this Article		Near‐Transducer Errors in Acoustic Doppler Current Profiler Measurements M. Muste, D. Kim, J. Gonzalez‐Castro, A. Burkhardt, and Z. Brownson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)164 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Previous studies have shown that velocities measured near the Acoustic Doppler Current Profiler (ADCP) transducers are biased low. The error was associated with two causes: acoustic ringing and the flow disturbance created by the submerged part of the ADCP in its vicinity. Acoustic ringing defines the resonance of the transducer and the associated electronics occurring after the acoustic pulse is generated until the vibrations die out. The local flow disturbance is induced by the flow blockage and the drag acting on the ADCP and it is commensurate with the ADCP submergence and its geometry. Given that these errors contaminate the measured velocities in the bins close to the transducers, they are collectively addressed in this paper as the near‐transducer error. The paper presents results of a study conducted in a laboratory flume with an ADCP specifically designed for reducing the ringing effect (ZedHed produced by Teledyne RD Instruments). The measurements were conducted in shallow, low‐velocity flows (i.e., bulk flow velocities between 0.5 ft/s and 3 ft/s and flow depths between 1 ft and 3 ft) where the near‐transducer error becomes increasingly significant. The results show that by operating the ADCP with minimum blanking distance the error in the velocity estimates near the transducers can be up to 8.23% from the mean velocity in the undisturbed channel (for a flow depth of 2 ft and velocity of about 3 ft/s), and up to 27.5% when the flow is very shallow (for a flow depth of 1 ft and bulk velocity of about 1 ft/s). The results of the study also indicate that the major fraction of the near‐transducer bias error is due to the ADCP blockage and the drag acting on the submerged part of the ADCP, with ringing playing a secondary role.

back to top

HYDRAULIC MEASUREMENT TECHNIQUES FOR PHYSICAL MODELS

Select this Article		Flow and Sediment Laboratory Measurements over Unsubmerged Roughness Elements A. N. Papanicolaou and C. Kramer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)165 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The overarching objective of this investigation was to evaluate the role of relative submergence on the formation and evolution of cluster microforms in gravel bed streams and its implications to bedload transport. The methodological component of this study was founded on the recent research findings of Papanicolaou et al. and Strom et al. about cluster formation, disintegration, and the effects of cluster evolution on bedload transport. An enhancement of the methodology was attempted to account for the role of relative submergence on cluster microtopography, a very important feature in gravel‐bed rivers that few to none have researched in a systematic way. Specifically, the methodology and experimental design of this research was based on the premise that in natural gravel bed streams, where the height of clast‐obstacles is generally of the same order of magnitude with the flow depth, the processes between the interaction of the flow and clasts play a dominant role in eddy taxonomy and flow prevailing mechanisms.

Select this Article		The Use of LSPIV to Measure Large Streamwise Vortices J. F. Fox, M. ASCE, A. Patrick, and S. Wood ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)166 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The impact of large streamwise vortices or macroturbulence upon suspended sediment transport and mobility of aquatic species is well recognized. In order to advance the understanding of large streamwise vortices, it is increasingly important to map the turbulent structures on a large scale domain such as for a total river reach. Large Scale Particle Image Velocimetry (LSPIV) serves as a promising experimental tool to map large streamwise vortices due to its extrusive nature and the ability to capture the dynamics of free‐surface flows over large areas, potentially from airplanes, helicopters, and satellites. This work explored the ability of LSPIV to capture the characteristics of large streamwise vortices in a controlled experimental setting where a gravel‐bed river was modeled. Visualization and statistical techniques were used to measure the largest coherent turbulent scales from LSPIV data obtained for unobstructed flow in a laboratory flume. Results revealed that LSPIV has the ability to capture free surface motion including sweeping and upwelling or ejections which indicate the upstream and downstream extent of the large streamwise vortices. Length scales and frequencies agree with published field and laboratory data for large streamwise vortices. The large streamwise vortices show quasi‐stable behavior for the conditions tested.

Select this Article		Scale Effects in Movable Bed Models of Rivers with Dominant Suspended Load Md. Manjurul Haque, Gerrit J. Klaassen, and Hans Gustav Enggrob ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)167 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Movable bed physical models are often used as a tool for the prediction of the morphological behavior of rivers and estuaries. But as a tool they have limitations in their own in terms of so‐called scale effects defined as differences between prototype and model due to deviations from some of the scale conditions. The consequences of these scale effects are sometimes serious as some important phenomena might not be reproduced correctly. This paper discusses for scale models of rivers in which suspended load is dominant the derivation of some important scale conditions and their application for the assessment of scale effects in reproducing flow, sediment transport and bed topography. Several numerical simulations were performed for a full scale U‐shape prototype bend and five of virtual physical models based on three velocity and two bed material diameter scales using a depth‐averaged 2D morphological model (Mike‐21C). This allowed to quantify scale effects by comparing the prototype with the “virtual physical models” created in the mind only. The results show that (1) the selection of velocity scale is very important and (2) neither the Froude nor ideal velocity scale is a good choice for movable bed models for rivers with significant suspended load with respect to scale effects.

Select this Article		The Effects of Relative Submergence on Flow Patterns around Large Particles in a Gravel Bed River C. M. Kramer and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)168 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The flow patterns around large particles in mountain gravel bed streams were examined. An emphasis was placed on the effects of these flow patterns when the relative submergence exceeded 3. To provide an improved understanding of the flow structures around the clasts, an in depth analysis of mean flow measurements was performed. On average, the velocity profiles were characterized by an inner layer that reflected mostly grain/skin resistance and an outer layer that mostly reflected form resistance. With the knowledge gained from these experiments, a practical application is to use strategically placed clast particles in a stream to help trap or entrain incoming particles near spawning grounds, thus helping to make and sustain a cleaner habitat for fish and other aquatic organisms.

back to top

INNOVATIVE HYDRAULIC MEASUREMENT TECHNIQUES

Select this Article		A Storm Runoff Simulator to Evaluate Grass Filter Strips and Other Storm Water Management Systems T. G. Franti and D. P. Shelton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)169 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A storm runoff simulator is needed to evaluate flow hydraulics, sediment trapping and water quality benefits of grass filter strips, small hydraulic structures such as storm drains, other stormwater management practices and similar bioretention systems. Based on an engineering analysis using MUSLE and HEC2, it was determined that a simulator could be developed for a 1 × 9 m grass filter plot, with resource constraints of 7,580 L stored water, 7.3 L s⁻¹ peak water flow rate and 0.71 metric tons of soil, for field to buffer area ratios (BAR) greater than 30:1, the maximum design criteria specified for grass filter strips by the Natural Resources Conservation Service. A runoff simulator water output control device operating under gravity flow conditions and using a feedback control system between and a flow meter and an actuated valve was designed, built and tested. A time‐compressed 10yr‐2hr SCS design hydrograph with a 7.3 L s⁻¹ peak flow rate was used to calibrate the simulator for optimal performance with large changes in flow rate and for compatibility with a variety of hydrograph shapes. When reproducing the compressed SCS hydrograph, the simulator maintained comparable efficiencies among repetitions; with a 2% error between root means square error and the total flow range. Hydrographs with step changes in flow rate, flow rate plateaus, multiple peaks and flow rates up to 9.8 L s⁻¹ could be simulated with comparable efficiencies and 4 to 6% error.

Select this Article		Comparison between Dispersion Coefficients Estimated from a Tracer Study and ADCP Measurements Meredith L. Carr, Chris R. Rehmann, and Juan A. González ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)170 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We evaluate the use of river velocity and bathymetry data measured with an acoustic Doppler current profiler (ADCP) to estimate the longitudinal dispersion coefficient K. Whenever mixing is controlled by shear dispersion, the dispersion coefficient can be estimated from a theoretical formula that relies on velocity measurements in a cross section. The relative ease and detail with which ADCPs measure velocities allows the dispersion coefficient to be estimated with greater frequency and spatial coverage in U.S. rivers. We conducted simultaneous ADCP and tracer measurements in the Kissimmee River in South Florida under bankfull threshold conditions. The ADCP method underestimates the dispersion coefficient obtained from the tracer study by about 40%. Flow in side channels and over part of the river floodplains likely led to dispersion of the dye cloud that the shear dispersion mechanism does not take into account.

Select this Article		Real Time Estimation of ADCP Bedload Velocity Using a Kalman Filter C. D. Rennie and F. Rainville ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)171 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An estimate of apparent bedload velocity (ν) can be derived from the difference between Differential Global Positioning System (DGPS) and acoustic Doppler current profiler (aDcp) bottom track (BT) measurements when BT is biased by moving bottom. A Kalman filter has been developed to integrate GPS and bottom track data to improve estimation of boat velocity during ADCP measurements under moving bed conditions. The boat velocity estimated using the Kalman filter is superior to boat velocity from raw DGPS data. In this paper we assess the improvement in estimation of ν using the Kalman filter as opposed to raw DGPS data. Specifically, a synthetic moving bed bias was generated. The synthetic moving bed bias had mean, variance, and distribution across the section as typically observed during bedload transport conditions, and had the advantage that it was known explicitly. The errors in estimated apparent bedload velocity derived using either raw DGPS data or the Kalman filter boat velocity were compared. It was found that the improved boat velocity from the Kalman filter yielded significantly (alpha=0.05) better estimates of ν, because boat velocity errors were reduced.

Select this Article		Using an ADCP, Depth Sounder, and GPS for Bathymetric Surveys Tracy B. Vermeyen, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)172 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The river outlet works at Fontenelle Dam, part of the Seedskadee Project in southwest Wyoming, has a long history of concrete abrasion damage. Consequently, the project manager has requested assistance to identify the cause of the damage. Reclamation's Water Resources Research Laboratory will conduct a physical model study to determine the cause of the damage and to design necessary modifications to prevent the damage from reoccurring. As part of the preparation for the model study, bathymetry data for the river outlet works channel was needed to construct the topography in the physical model. The project manager also requested bathymetry data for the river outlet works structure to verify areas of abrasion damage and material accumulation identified during a recent underwater inspection. The bathymetric data were collected using an acoustic Doppler current profiler (ADCP), depth sounder and a hand‐held GPS receiver. This paper presents details on the bathymetric survey techniques, considerations regarding depth and positional uncertainty, and a comparison of the bathymetric data with design data.

back to top

BRIDGE PIER AND ABUTMENT SCOUR

Select this Article		A Review of Bridge Abutment Scour Countermeasures B. D. Barkdoll, B. W. Melville, and R. Ettema ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)173 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The ability to protect bridge piers and abutments from scour is critical to bridge safety. Excessive abutment scour can cause high maintenance costs or even bridge collapse resulting in the interruption of traffic and possibly death. Two approaches to scour mitigation have been taken. These are (1) bank‐hardening and (2) flow‐altering countermeasures. Bank‐hardening methods are composed, among others, of riprap, cable‐tied blocks, and geobags. Flow‐altering countermeasures include spur dikes, guidebanks, parallel walls, and collars. Selection of a countermeasure involves a life‐cycle cost assessment for the particular site in question as well as social and environmental issues. Three new countermeasures include parallel walls, spur dikes located locally to the abutment, and horizontal collar‐type plates attached to the abutment. All three of these new countermeasures have been proven successful in the laboratory. This work will be detailed in an upcoming report as part of the NCHRP 24‐18A project.

Select this Article		A Practical Approach to Estimating Scour Depths at Bridge Abutments R. Ettema, A. Yorozuya, T. Nakato, and M. Muste ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)174 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Observations of bridge‐abutment scour lead to a practical new approach for estimating realistic scour depths at bridge abutments. Prior design approaches usually lead to unrealistically deep estimates of abutment‐scour depth. The observations presented stem from flume experiments conducted with abutments with approach embankments subject to a range of erodibility conditions: fixed embankment on fixed floodplain; riprap‐protected erodible embankment on readily erodible floodplain; and, unprotected readily erodible embankment on readily erodible floodplain.

Select this Article		Riprap Sizing for Bridge Pier and Abutment Countermeasures L. W. Zevenbergen, M. ASCE, P. E. Clopper, M. ASCE, and P. F. Lagasse, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)175 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Many equations are available for sizing riprap protection for bridge piers and abutments. These design equations can give significantly different results for protecting the same installation. This paper provides an overview of a review of riprap sizing methods performed as part of the National Cooperative Highway Research Program (NCHRP) Project 24‐23, “Riprap Design Criteria, Specifications, and Quality Control.” The performance of twelve (12) pier riprap sizing equations was evaluated by comparing the predicted size against three laboratory data sets. Adjustment factors for pier shape were also evaluated because the laboratory data includes tests of square and round nose piers. Flow velocity is the primary variable for determining riprap size. One‐dimensional models often do not provide accurate estimates of flow velocity for bridge abutment areas located at the ends of embankments that encroach significantly into floodplains. Therefore, 2‐dimensional hydraulic modeling was performed to test methods for estimating flow velocity at abutments and guide banks and additional guidance was developed.

Select this Article		Local Scour at Complex Piers Bruce Melville, Stephen Coleman, and Stephen Priestley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)176 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A methodology to predict local scour depth at a complex pier is presented that recognises the relative scouring potentials of the components of complex piers, and the transition of scouring processes occurring for varying pile‐cap elevation. Scour depths are predicted over the entire range of possible pile‐cap elevations using a combination of existing expressions for scouring respectively at uniform piers, caisson‐founded piers, pile groups with debris rafts, and pile groups alone. The validity of the method is confirmed using measurements of local scour at complex piers, and a case study is used to highlight application of the methodology. For design purposes, the method highlights respective pile‐cap elevations that maximise (i.e. to be avoided over the pier life) and minimise local scour at complex piers. The method reinforces that where the pile‐cap elevation relative to the bed can vary with time at a bridge site, potential local‐scour depths need to be assessed over the range of possible pile‐cap elevations for the pier.

back to top

BRIDGE SCOUR ISSUES

Select this Article		Research Needs for Scour at Bridge Foundations — An Update P. F. Lagasse, L. A. Arneson, and L. W. Zevenbergen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)177 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In 1997, the National Cooperative Highway Research Program (NCHRP) developed a Strategic Plan for research on scour at bridge foundations. The Plan identified, prioritized, and developed problem statements for thirty‐five studies in seven topical areas to respond to the most critical research needs. This paper evaluates progress on the Strategic Plan by NCHRP, the Federal Highway Administration (FHWA), the U.S. Geological Survey (USGS), individual State highway agencies, and others. Based on a literature search and evaluation of research activities in stream stability and bridge scour in the 1995–2004 period and a survey of State DOTs, research needs for the next 5 – 10 years are identified.

Select this Article		Guidelines for Risk‐Based Management of Bridges with Unknown Foundations S. M. Stein and K. A. Sedmera ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)178 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Research is currently being funded by the National Cooperative Highway Research Program (NCHRP) to develop risk‐based guidelines to assist bridge owners in evaluating and prioritizing various courses of action for managing bridges with unknown foundations for scour failure. Currently, over 60,000 bridges over water have unknown foundations. Managing these bridges for failure risk is extremely difficult since a critical scour depth to cause failure cannot be determined in the absence of foundation information. The guidelines being developed under this research project focus on the following: (1) Estimating risk of failure as a function of estimated failure probability and associated economic losses, (2) Setting performance standards for various bridge classifications, (3) Recommending data collection activities (including nondestructive testing of foundations), (4) Recommending scour monitoring activities, and (5) Recommending scour countermeasures. The guidelines being developed will present a logical plan of action for bridges with unknown foundations. Given the large population of such bridges and the potential cost of management options, these guidelines will assist bridge owners in selecting and prioritizing management activities. Once the guidelines are developed, they will be applied to dozens of case studies for validation with real‐world examples. After the case studies are completed, the guidelines will be finalized and made available to bridge owners nationwide.

Select this Article		Pressure‐Flow Scour: A Re‐Examination of the HEC‐18 Equation D. A. Lyn ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)179 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Unsatisfactory features of the equation that is recommended in HEC‐18 (Richardson and Davis, 2001) for predicting pressure‐flow scour are pointed out. These are found to stem from the basic model of the regression analysis performed by Arneson (1997), and an unfortunate transformation resulting in the final form of the equation. Alternative approaches are examined.

back to top

CULVERTS AND BEAVER DAMS

Select this Article		Experimentally Determined Inlet Loss Coefficients for Buried‐Invert, Circular Culverts D. S. Anderson and B. P. Tullis, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)180 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In current practice, inlet loss coefficients for buried‐invert culverts are either ignored or approximated using traditional culvert design data due to a lack of data specific to fish passage culvert geometries. This study included the experimental determination of inlet loss coefficients for a circular culvert with an invert burial depth of 50%. Culvert inverts are buried when a simulated streambed is desired in the culvert for fish passage applications. This paper outlines the experimental methods used to determine inlet loss coefficients relative to fish passage culvert geometries and presents the data relevant to the hydraulic design and evaluation of these culverts.

Select this Article		Increased Roughness in Reinforced Concrete Box Culverts Adam S. Hill, Rollin H. Hotchkiss, Ph.D., P.E., Kayla M. Culmer, and Michael A. Miraglio, III ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)181 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents results of an experimental investigation to increase roughness within the barrel of a concrete box culvert using trapezoidal‐shaped corrugations with a shape similar to pavement underlay on bridge decks. Half‐scale corrugations were placed on the bottom and both sides of a tilting flume 21 meters long, 0.90 meters wide, and 0.53 meters deep in Albrook Hydraulics Laboratory at Washington State University. During the experiment, wood cut to the shape of bridge decking simulated the concrete forms expected to be used in the field. Experimental flow rates ranged from 24–144 L/s. Experimental slopes ranged from 0.3–10.1%. Depths were measured with a point gage in several points upstream of corrugations, within the corrugations, and downstream of corrugations. Depths were measured at both the crest and the trough within corrugations. Manning's n was found to be dependent on the submergence ratio in a power function. In a range of submergence ratios between 1.33 and 3.0, the Manning's n ranged from 0.03–0.05 after scaling to full size. This increase in Manning's n would lead to a 40–60% velocity reduction in full scale conditions.

Select this Article		Hydraulic Characteristics and Dynamics of Beaver Dams in a Midwestern U.S. Agricultural Watershed M. C. McCullough, D. E. Eisenhauer, M. G. Dosskey, and D. M. Admiraal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)182 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Populations of North American beaver (castor canadensis) have increased in the past decades throughout the Midwestern U.S., leading to an increase in the frequency of beaver dams in small streams. Beaver dams form ponds and slow water velocity. Multiple dams create a stair‐step effect on the water surface profile. The hydraulic and geomorphic influence of beaver dams on streams in the focus of this study. The study area, Little Muddy Creek watershed in eastern Nebraska, is predominantly in agricultural land use. Since the early 1900's, streams in the watershed have undergone deep incision, with new floodplains being established. The main reach of this 3^rd‐order watershed was surveyed for beaver dams from 2003 to 2005. Dam locations were documented with mapping grade GPS, integrity of dam structure was noted and upstream and downstream water surface elevations were measured. Failure of dam structure was documented following runoff‐producing storms. While some dams were repaired within weeks, others were abandoned and left to degrade, causing a significant and transient change in the water surface profile of the stream. Tests were conducted in the laboratory to determine discharge rating curves for a simulated beaver dam. The upstream and downstream slopes and height of the dam were based on field‐surveyed characteristics. Initial tests were run using a smoother surfaced dam, followed by tests with sticks attached to the smooth surface mimicking the roughness of a beaver dam. The rating curve of the beaver dam shifted to the right compared to the smooth dam, indicating that the roughness of the sticks significantly altered the stage‐discharge relationship. Field observations showed that the spatial arrangement and hydraulic condition of beaver dams were temporally dynamic in both short and long term scales. Field and laboratory results indicate that beaver dam structures were similar to and could be modeled as broad‐crested weirs.

back to top

FISH PASSAGE AND HABITAT DESIGNS

Select this Article		Fish Passage over Weirs in Midwestern Streams D. C. Dermisis and A. N. (Thanos) Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)183 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this investigation is to employ the state‐of‐the‐art large scale particle image velocimetry (LSPIV) technique for free surface flow measurements around and within the vicinity of hydraulic structures (e.g. weirs, ladders) used for fish passage in the loess region of Western Iowa, USA. Knowledge of the two dimensional (2‐D) free surface velocity allows engineers and biologists to determine the hydraulic performance of the above structures as it relates to fish passage. The magnitude of the velocity will provide unique information about the level of turbulence around and within the vicinity of the structures, the approach velocity magnitude, the dissipation rate and the forces acting on juvenile and adult fish passing through the structures. The LSPIV technique is founded on similar principles with those of the particle image velocimetry (PIV). LSPIV is a powerful and efficient technique for measuring river surface velocities especially in natural ‐large scale‐ systems which are of the primary interest of this research. It is a cheap method as it needs, basically, an inexpensive video equipment (camera) and a geodetic survey to describe the region of interest (ROI). The water velocity vector magnitude and direction are calculated by dividing the estimated displacement of the particles with the time interval between two sequential images. The LSPIV technique does not require calibration and it is well‐suited for measuring in very shallow flows quickly and accurately; also can be used to estimate the discharge in conjunction with bathymetry information and assumed velocity distribution over the depth. Validation of the LSPIV measurements will be attained with the use of a SonTek flow tracker.

Select this Article		Design and Assessment Techniques for Fish Passage at Culverts and Bridges Christopher M. Frei and Rollin H. Hotchkiss ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)184 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Research at Washington State University is bringing together state‐of‐the‐art and state‐of‐practice fish passage design criteria from across the nation — covering culvert and bridge installations or retrofits. A Federal Highways manual entitled Hydraulic Engineering Circular 26 “Design of Fish Passage at Bridge and Culverts” (HEC‐26) will be the amalgamation of a comprehensive literature review, input from state departments of transportation, non‐governmental organizations, and other interested parties. HEC‐26 will include a compilation and comparison of design methods, culvert and stream assessment techniques, case studies, and design examples. The manual will provide a set of guidelines to any party interested in the design or retrofit of culverts and bridges to meet fish passage requirements, and is intended to streamline the design process. This paper presents a summary and comparison of design, retrofit and field assessment techniques employed to evaluate the barrier status of existing culverts. A number of alternatives have been developed for the design of fish‐crossings, and although the exact specifications of each method vary from state to state, the overarching concepts remain the same. General methodologies fall into two categories, which meet the needs of most crossing structures: Stream Simulation and Hydraulic Design. The appropriateness of the design method is dictated by the level of stream‐reach connectivity required and project budget. Fish passage assessment is essential to prioritize culvert improvement projects, and shows many similarities across the nation. The results presented within this paper will be used to shape the discussion of design procedure and culvert assessment techniques within HEC‐26.

Select this Article		A Study of the Free Surface Flow on Brownlee Dam Cagri Turan, Brady McDaniel, Marcela S. Politano, Pablo M. Carrica, and Larry Weber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)185 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Many spillway designs form surface jets that discharge in relatively large reservoirs. It has been often observed that strong liquid entrainment is caused by these surface jets. This water entrainment can have important environmental and ecological impacts. Because of this entrainment the Total Dissolved Gas (TDG) produced in the spillway is diluted with low TDG water coming from the powerhouse. In addition, low Dissolved Oxygen (DO) waters from the powerhouse are rapidly oxygenated by mixing with the aerated spillway discharge. A numerical and experimental study of the tailrace flow on Brownlee Dam on the Snake River is presented to study this entrainment. Experimental data was obtained on a 1/48 physical model, where three dimensional velocity fields were measured using an AVD probe. Numerical models were evaluated, including the effect of turbulence models (k‐epsilon and Reynolds stress model, RSM), free surface approximation (Volume of Fluid, VOF, surface capturing method or rigid lid) and single‐phase or two‐phase mixture. The commercial CFD code FLUENT was used. Multi‐block structured grids were used to accommodate the complex geometry that includes a spillway deflector, power house units and the bathymetry. The velocity fields at different depths were compared against the experimental data taken on the physical model. The ability of the model to predict the experimental results is discussed. Both experimental and numerical results show a strong water entrainment from the powerhouse to the spillway when deflectors are used. Predicted results of the model will contribute to the understanding of the physics of this entrainment.

Select this Article		Creating Wet Acres in the Missouri River for Fish Populations A. Papanicolaou and M. Elhakeem ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)186 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The overarching goal of this research is to evaluate the hydraulic performance of different structures found in the Missouri River for creating new shallow water habitat (SWH). Such structures include dikes found in their original form, notched dikes and chevron dikes. The hydraulic performance of the aforementioned structures will be evaluated via detailed field monitoring studies for a range of flow conditions and for different locations within the stream. In addition, a 2‐D hydrodynamic model will be used to describe the flow patterns around the hydraulics structures. The code will provide for different flow conditions the flow depth and velocity variation introduced by the structures. This paper presents the first phase of this ongoing research by comparing the numerical simulations with the field measurements.

back to top

FLOWS DOWNSTREAM OF SPILLWAYS AND DIVERSION STRUCTURES

Select this Article		Water Entrainment and Mixing Due to Spillway Discharges Cagri Turan, Pablo M. Carrica, Marcela S. Politano, and Larry Weber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)187 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Many spillway designs form surface jets that discharge in relatively large reservoirs. It has been often observed that strong liquid entrainment is caused by these surface jets. Velocity measurements at both model and prototype scale for Wanapum Dam, Washington, and at model scale for Brownlee Dam, Idaho, indicate that the jet configuration and strength affect the entrainment. This water entrainment can have important environmental and ecological impacts. In the abovementioned power dams, water coming from the powerhouse is attracted to the spillway, causing beneficial phenomena. The Total Dissolved Gas (TDG) produced in the spillway is diluted with low TDG water coming from the powerhouse. In addition, low Dissolved Oxygen (DO) waters from the powerhouse are rapidly oxygenated by mixing with the aerated spillway discharge. The mechanisms causing this entrainment are poorly understood. Most of the studies found in the literature explain the entrainment with turbulent mixing. Aeration and free‐surface instabilities contribute to modify the turbulence structure and have an effect on the entrainment. Standard RANS numerical models fail to predict the degree of entrainment observed experimentally. In this work a study of the entrainment in free surface jets, with the objective of reveal the reasons for the poor performance of RANS solvers in predicting water entrainment, was carried out. A numerical model was developed to resolve the free surface using the commercial code FLUENT. A submerged round jet parallel to the free surface was modeled and the effect of turbulence models was analyzed. Following a brief description of the models, the paper discusses the mechanisms involved in entrainment in spillways by comparing models with available experimental results.

Select this Article		Flow Separation Downstream of Equal and Opposing Flow Junctions in Open Channels Carl Frizzell and David Werth, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)188 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract It is common in different open channel flow systems, such as cooling tower basins, irrigation systems, and other water distribution systems, for two flows of equal magnitude to collide and then turn 90‐degrees into a downstream channel. When this occurs two separation zones are formed in the downstream channel. This separation is often of interest during the design or evaluation of these types of structures to evaluate the potential for a hydraulic jump or choked flow conditions to occur. Numerous studies of open channel junctions have been conducted but very little information exists for the particular case of two opposing flows which collide and turn 90‐degrees. This paper presents the results of a physical model study to evaluate the separation zones in this hydraulic phenomenon. The physical model study was used to validate an analytical method of the opposing flow condition. There was good agreement between analytical method and the physical model. The validated analytical method approach can be used to predict the maximum width of the separation zone. This paper summarizes the results of these studies and presents an analytical tool which can be used to asses the potential for hydraulic jumps or choked flow conditions in cooling towers, irrigation channels, and a variety of other water distribution applications.

Select this Article		Converging RCC Stepped Spillways S. L. Hunt, A. M. ASCE, K. C. Kadavy, P.E., and D. M. Temple, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)189 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) estimates that nearly half of the small watershed dams constructed with their assistance will reach the end of their planned service life within the next 10 years. While many of these structures were originally built in rural environments, urban communities have encroached upon these structures over the years, making it difficult to address issues such as the maintenance of adequate spillway capacity to meet current dam safety standards. The urban infrastructure surrounding these structures limits the options available for dam rehabilitation. For instance, raising the dam or widening the existing auxiliary spillway to increase spillway capacity is often not a viable option due to land right constraints or changes in topography. Therefore, one of the more popular choices for increasing spillway capacity is the use of roller compacted concrete (RCC) stepped spillways. Two advantages of RCC stepped spillways are that they can be placed over the top of the dam and that they can provide considerable energy dissipation within the spillway chute. When placing an RCC spillway over an existing embankment dam, it is often desirable for the width of hydraulic control section to be greater than the width available to outlet the flow into the downstream channel. A generalized study utilizing a three‐dimensional, 1:22 scale physical model was conducted to evaluate the influence converging training walls have on the flow characteristics on a stepped spillway. Vertical walls having convergence angles ranging from 0 degrees to 70 degrees were tested in conjunction with a spillway having a chute slope of 3(H):1(V) and a prototype step height of 0.3 m (1 ft). Water surface profiles in the central area of the chute and along the walls were collected and analyzed for each spillway configuration. Results of the study are presented in a format that will assist engineers in determining the required wall height for this type of a converging chute spillway.

Select this Article		The Lower Olentangy River Watershed Lowhead Dams Feasibility Study Bryon F. Ringley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)190 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Friends of the Lower Olentangy Watershed (FLOW) was formed in August of 1997 with a mission to increase public awareness of the extensive environmental, recreational and cultural resources of the Lower Olentangy River Watershed and to promote responsible policies and uses of the river. FLOW drafted a watershed action plan based on water quality data collected by OEPA in 1999 and published in 2001. This plan, the Lower Olentangy Watershed Action Plan, was endorsed by OEPA and ODNR in 2005. One of the nine priorities listed in the plan is restoration of the mainstem through dam removal or dam modifications.

back to top

LABORATORY MODEL STUDIES OF HYDRAULIC STRUCTURES

Select this Article		Model Study for the Design of Emergency Stoplogs Deployed in a Complex Flow Field — Part 1: Experimental Results Marian Muste, Larry Weber, Troy Lyons, Pete Haug, and Duncan Hay ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)191 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The model study objective is to determine the optimum configuration for a multi‐segment cable‐deployed vertical gate to block flow through a fish bypass when primary gates are not functional. In such emergency situations, gate segments are subjected to complex three‐dimensional flows that vary with gate deployment elevation. The 1:24 scale model incorporated a comprehensive experimental setup controlled by LabVIEW data acquisition and visualization software allowing real‐time measurement and visualization of the forces during gate deployment. Thirty gate segments (stoplogs) and lifting beam shape combinations were tested to minimize submerged gate closure weight and measure maximum cable tension. The experimental tests were complemented by companion Computational Fluid Dynamic (CFD) simulations aimed at substantiating the flow features and directing the phasing of the experimental program. This paper describes the experimental setup, procedures, and experimental phasing, as well as synergistic use of laboratory and CFD data.

Select this Article		Model Study for the Design of Emergency Stoplogs Deployed in a Complex Flow Field — Part 2: Numerical Results Marcela Politano, Pablo Carrica, Cagri Turan, Larry Weber, and Duncan Hay ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)192 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An emergency closure system using stoplogs was designed to stop the flow through a fish passage when the primary gates are not functional. Physical and numerical hydraulic models were conducted to develop the stoplog design for the Wanapum Future Unit Fish Bypass. Different design alternatives were evaluated to minimize the maximum cable tension during deployment and the hydraulic uplift force that could prevent closure. The hydraulic force on the stoplog and lifting beam were calculated using the commercial code Fluent. The Volume of Fluid (VOF) method was used to simulate the free surface. Structured and unstructured hybrid grids were used to simulate the complex geometry near the stoplogs. The predicted flow field for the stoplogs at different elevations are presented and discussed. Two‐dimensional numerical results are compared against experimental data taken on the 1:24 scale laboratory model and used to understand the physics underlying the behavior of each geometric design.

Select this Article		Hydraulic Modeling Study for Rio Grande Diversion Structure at Albuquerque Jungseok Ho, Tom Gill, Brent Mefford, and Julie Coonrod ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)193 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hydraulic model tests of flow properties of diversion structure gates are presented for the proposed diversion structure on the Rio Grande at Albuquerque, New Mexico. The Rio Grande diversion structure is composed of independently controlled adjustable height gates across the channel, a fish passage through the diversion structure, and an intake channel for 3.7 m³/s of maximum river diversion. A 1:24 scale distorted movable bed hydraulic physical model was constructed at the Water Resources Research Laboratory of U.S. Bureau of Reclamation in Denver, Colorado. The hydraulic performances of the diversion structure that were tested include the gates operation over various flow rates, flow transitions and sediment exclusions at the intake channel. Two‐dimensional hydrodynamic numerical model was built to simulate the flow properties around the diversion structure. Velocity vector computations around the intake structure and the diversion gate openings are compared with the physical test measurements. The numerical model shows very good agreements with the physical model measurements.

back to top

RIVER ENGINEERING

Select this Article		Flow Around Submerged Barbs in the Raccoon River Iowa B. G. Wardman and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)194 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The placement of bendway weirs (barbs) has beneficial effects on bank stability and river ecology by increasing the conveyance at the center of the channel. This study focuses on the Raccoon River, Iowa, USA, and specifically the stabilization of the north riverbank immediately upstream of the US‐169 highway bridge. The integrity of the north bridge abutment, originally built in 1950, is in danger as the river continuously erodes the surrounding soils. The Iowa Department of Transportation (IDOT) proposed solution to the problem is to install a combination of barbs and bendway weirs on the north bank upstream of the bridge to stabilize the bank. Although many recent studies have focused on the flow effects and scour holes produced by the addition of barbs, few detailed design guidelines exist. The objective of this study is to employ fundamental knowledge to evaluate the effectiveness of the proposed IDOT design and eventually produce a comprehensive, non‐site specific barb design to increase bank stability. The study utilizes a commercial Surfacewater Modeling System (SMS) software package with a 2‐D solver to evaluate the large scale effects of the design. Quantitative and qualitative evaluation based on previous fundamental studies showed the IDOT design effectively reduced the flow‐induced shear stress, velocity, and depth along the river bank. Results also showed the current IDOT design will produce adequate sedimentation between structures and effectively move the bank line back towards its historic location. Future results from the continuation of this study will help to further reduce the ambiguity of barb design.

Select this Article		Hydraulic Design of a Lazy River Bruce M. McEnroe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)195 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Lazy rivers are popular attractions at modern aquatic centers and water parks. These recreational water channels carry patrons on floating tubes around a meandering loop. The current is maintained by pumps that withdraw a small fraction of the flow from the channel through large bottom grates and return it to the channel in jets directed downstream. This paper presents the hydraulic relationships needed for lazy‐river design. These relationships account for the propulsion of the flow by the water jets and the resistance to flow resulting from friction, bends and drag forces on standing persons. The total pump output power is minimized when the downstream component of the jet velocity equals twice the desired current speed. However, other practical considerations generally favor a higher jet speed. Field tests on three lazy rivers indicate that a Manning n value of 0.015 is sufficient to account for boundary friction, bend losses and other local losses. Persons standing in the flow cause added drag, which can reduce the current speed substantially. A design example illustrates the practical application of the relationships and experimental findings. The investigations presented in this paper were conducted for Water's Edge Aquatic Design LLC of Lenexa, Kansas. Water's Edge Aquatic Design is a leading design firm specializing in aquatic centers and water parks. The relationships in this paper have been applied successfully to numerous lazy‐river design projects.

Select this Article		Sediment Yield Investigation and Method Comparison for Southern California Coastal Watersheds Martin J. Teal and David S. Smith ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)196 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The U.S. Army Corps of Engineers, Los Angeles District, and the Office of Water Resources of Marine Corps Base Camp Pendleton contracted with WEST Consultants, Inc. (WEST) to perform watershed analyses of three small coastal basins on the base in southern California. Although this project included hydrologic, hydraulic, and sediment yield studies, the focus of this paper will be the sediment yield estimates. Using subbasin delineations developed for the hydrologic modeling, and extensive geographic information system (GIS) data sets, WEST estimated the amount of sediment yield for these watersheds using four different methods: (1) U.S. Army Corps of Engineers, Los Angeles District (LA Corps), (2) Modified Universal Soil Loss Equation (MUSLE), (3) Dendy and Bolton, and (4) Taylor. Each of the above methods was developed at a different time for slightly different purposes using different input parameters. A brief review of the different methods is provided before results from the different methods for the various subbasins are compared. Sensitivity of the various methods to certain input parameters is explored and recommendations are made regarding the methods presented.

Select this Article		The Use of Hydrologic and Ecological Models to Guide Restoration Efforts Misganaw Demissie, Ph.D., P.E., Yanqing Lian, Ph.D., David White, Ph.D., and Jiing‐Yun You ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)197 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Illinois River has been significantly altered physically and hydrologically over the last century, resulting in a degraded ecosystem. One of the major changes was the construction of levees in the floodplain to protect agricultural levee and drainage districts (LDDs) from regular flooding from the river. A total of 24 LDDs were established in the lower Illinois River between 1987 and 1916. Removal of a large part of the river's floodplain contributed to more rapid water‐level fluctuations during the growing season that inhibit establishment of native vegetation along the river. Major ecological restoration efforts are underway in the Illinois River basin. One of the goals of those restoration efforts is to re‐establish the natural hydrology of the river and its floodplain to the extent possible without disrupting economic activities along the river. One of the options under consideration is the reconnection of some of the floodplain with the river. Hydrologic and ecological models are being used to assess restoration potential and to guide restoration efforts along the river. Water budget and unsteady flow models of the Illinois River are being used to evaluate water level fluctuations within the LDD. Modeling results are then used as input to a vegetation model that simulates plant growth based on water depth, fluctuation, and duration. This paper presents research results for a selected segment of the Illinois River.

back to top

SEDIMENTATION ISSUES AND PROCESSES

Select this Article		Stability of Non‐Cohesive Sediments under Conditions of Pore Water Flux Pinar Cakir and Steven J. Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)198 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Typical approaches to the determination of sediment stability generally only consider the influence of applied shear stresses due to advective flow over the sediment bed. However, in the case of fine‐grained sediments, it is possible that the pressure gradients created by groundwater discharging to the stream bottom may result in a significant additional de‐stabilizing effect. Several previous experimental studies have been conducted to investigate the role of injection or suction through a porous stream bed on the resistance to bed erosion. The results of these studies yield contradictory findings with injection, for example, contributing to bed stability in some studies while stabilizing it in others. A consideration of the fundamental forces acting on a bed particle is presented, providing a framework in which these conflicting results can be understood. The results of a preliminary study with a non‐cohesive fine sand, d₅₀ = 500 μm is presented. A constant head water supply is provided at the bottom of the sand bed to provide different rates of vertical water movement through the sediment bed including a few cases with suction through the sediment bed. The influence of the critical shear stress for initiation of motion will be compared to the zero recharge condition to determine the magnitude of vertical hydraulic gradient required to produce a significant change in the critical shear stress.

Select this Article		A Bayesian Unmixing Model for Land‐Use Fingerprinting Using Delta⁵N and C/N J. F. Fox and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)199 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this study, a new unmixing model is presented for land‐use fingerprinting eroded‐soil using delta⁵N and C/N. The model is specified within the Bayesian Markov Chain Monte Carlo framework and is capable of unmixing erosion sources characterized by multiple erosion processes. A unique attribute of the formulation is the use of a truncation parameter to account for uncertainty during the erosion process. The model was applied for fingerprinting soils from forest and agriculture land‐uses in Jerome Creek sub‐watershed of the Upper Palouse Watershed, Northwestern Idaho. Multiple processes including upland rill erosion and floodplain headcut erosion are represented within the agriculture region of the Upper Palouse. A sensitivity analysis for the unmixing model and comparison of the model with sediment yield estimates for the land‐uses add confidence to the accuracy of the model.

Select this Article		Application of Modified Log‐Wake Law in Open‐Channels Junke Guo and Pierre Y. Julien ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)200 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We extend the modified log‐wake law, which was developed for turbulent pipe and boundary layer flows, to open‐channel turbulence. Like those in pipes and boundary layers, turbulent velocity profile in open‐channels can be approximated with three components: (1) the law of the wall that results from the constant bed shear stress; (2) the law of the wake that reflects the effects of gravity, secondary currents and bed roughness; and (3) the cubic correction near the maximum velocity. The modified log‐wake law compares very well with experimental data from Coleman, Lyn, Kironoto and Graf and Sarma et al. It also replicates the measured velocity profile of cross‐section of the Mississippi River. In particular, it can well model the velocity dip phenomenon in open‐channels where the conventional log‐wake law fails.

back to top

FLOOD FORECASTING AND MANAGEMENT I

Select this Article		Construction of the FFWS Using Supervised and Unsupervised Performance in the Small Catchment Sungwon Kim, Ph.D., P.E. and Kibum Park, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)201 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The radial basis function neural networks model (RBFNNM), a kind of hybrid neural networks model, is developed and applied to construct the flood forecasting and warning system (FFWS) in small catchment, South Korea. The RBFNNM consists of supervised and unsupervised training performance in the networks system. The parameters of the RBFNNM such as centers, widths, connection weights, and biases are determined by the RBFNNM training performance. The RBFNNM validation performance is also carried out using these parameters. The results of the RBFNNM training and validation performance are compared with those of the two multilayer perceptron neural networks model (MLPNNM). The two MLPNNM are embedded with the one step secant backpropagation (OSSBP) and resilient backpropagation (RBP) algorithm respectively. The RBFNNM shows better results than the MLPNNM‐OSSBP and MLPNNM‐RBP slightly on the basis of the statistical analysis and flood hydrograph respectively. The constructed FFWS using the RBFNNM spent less time for the training performance and can be easily used by the hydrologists with little background knowledge of the RBFNNM. This system, furthermore, can enable many local officers and engineers to protect large flood disasters and save the private life and wealth in the Wi‐stream catchment, South Korea.

Select this Article		Flood Estimation by Various Techniques for Small and Large Catchments Abdul Razzaq Ghumman, Muhammad Masood Ahmad, and Muhammad Ali Shamim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)202 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Rainfall runoff relation is very complex and depends on so many factors which require numerous assumptions. Misleading results may be obtained due to over simplification of the process. The various formulas developed for estimation of peak flood discharge are generally based on single geometric parameter, the catchment area which does not reflect true discharges on which hydraulic structures like protection gabion walls, weirs, protection embankments, small irrigation weirs built on torrential flood channels, culverts and bridges are designed. This results in loss of precious money of the state and repeated rehabilitations. This paper presents a procedure for estimating the peak flood discharge. A novel regional mathematical rainfall‐runoff model was developed by full convolution of the synthetic unit hydrograph known as Snyder Method extended to include design return period of the selected storm and aerial reduction factor analysis. The model was tested against actual stream flow records by incorporating the flow records in the form of a regional flood frequency curve. The Synthetic Unit hydrograph and the design storm are related to find flood hydrograph corresponding to the design storm which may be routed through the hydraulic structure. Finally the developed mathematical model was analyzed for variation with respect to parameters of which it is composed of. The results were found within satisfactory limits of statistical tests.

Select this Article		The Coordinated Flood Control Operation Rules at the Upper and Lower Jinhu Reservoirs Jian Liu, Ph.D., M. ASCE, Wen Xiao, Ph.D., Peng Lou, and Minghua Huang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)203 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The concerted flood control operation rules at the upper and lower Jinhu reservoirs on the Bijiasha River in Shenzhen, China were discussed in this study. The upper and lower Jinhu reservoirs play an important role in the flood control in Shenzhen City. The upstream flood forecast and downstream hydrological information were not considered in the present operation modes. In order to improve the reservoir operation modes, the concerted real‐time operation rules for the two reservoirs were developed in consideration of the hydrological information of the inflows, and the water level of the downstream river channel. In the new operation rules, the releasing discharges from the two reservoirs were determined according to their regulating capacities, and the downstream water level in the channel from the dams to the Nigang gaging station where the real‐time water level and discharge data are available. The uncertainty of the flood forecast and the downstream discharge forecast data is taken into account during the process of determining the releasing discharges. In actual operation, the floodgate opening are adjusted in a define time because of the floodgate mechanical performance. The influence of the downstream water level on the reservoir releases was considered from the safety view of point. The effects of the newly developed operation rules were verified by a 50‐year flood. The retention effects performed by the new operation rules are better than those by the present modes. The new operation rules are operated easier than the present ones, and provide higher safety to the reservoirs and the downstream river channel.

back to top

FLOOD FORECASTING AND MANAGEMENT II

Select this Article		Flood Hazard Analysis and Protection Plan for a Residential Development Douglas Hamilton, Parmeshwar L. Shrestha, Jene E. Lyle, M. ASCE, Macan Doroudian, M. ASCE, and Philip J. Shaller ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)204 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An investigation was carried out to develop a flood hazard analysis and flood protection plan for a proposed residential development located in Indio, California. The project area is part of an existing floodplain that straddles portions of the alluvial fans derived from Thousand Palms Canyon and Pushawalla Canyon. Floodwaters emanating from a channel located west of the project area impact the project site. A two‐dimensional flood routing model was applied to study the progression of a flood flow in the existing floodplain. Processes simulated included overland flow, infiltration, and bottom boundary roughness. Elevations were based on USGS DEM, rough grading plans, high‐resolution LiDAR survey data, and data from a field reconnaissance survey. Model results were analyzed to determine the peak discharges into the proposed development. A channel was proposed to intercept the peak flows crossing the western boundary of the proposed development and convey these floodwaters southward along the western boundary and then eastward along the southern boundary of the project. The U.S. Army Corps of Engineers' River Analysis System (HEC‐RAS) was utilized to predict water surface elevations in the proposed channel, and to establish freeboard conditions with respect to pad elevations. To account for the interception of flows along the western boundary, the flows in the proposed channel were progressively increased to the peak flows. To simulate the outflows across the southern boundary, lateral weir flow was assumed to occur. The results of the analysis show that the proposed flood control channel accept and discharge the floodwaters at the historical locations. The U.S. Army Corps of Engineers' HEC‐6 model was used to conduct sediment transport simulations in the floodplain and onsite channels to determine the potential for sediment deposition. Model results were analyzed to estimate the sediment deposition for each cross section at the peak flow of the event, and at the end of the event. The results of our model studies indicate that sediment is transported through the system well and does not interfere with the function of the proposed stormwater channel.

Select this Article		Evolution of Bulletin 17B for Flood Frequency Analysis in the United States J. R. Stedinger and V. W. Griffis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)205 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The current methodology recommended for flood‐frequency analyses by U.S. Federal agencies is presented in Bulletin 17B. Bulletin 17 was first published in 1976; minor corrections were made in 1977 resulting in Bulletin 17A, which was later succeeded by Bulletin 17B published in 1982. The fields of hydrology and flood frequency analysis have substantially advanced since Bulletins 17‐17A‐17B were published. As Bulletin 17B approaches its 25^th birthday, it is time for the guidelines to be updated. New techniques are now available that correct known problems with Bulletin 17B and improvements should now become part of the Bulletin's recommended procedures. Such changes would provide: (1) statistically appropriate and efficient procedures for the computation of the regional skew and its precision that recognize that sample skewness estimators are relatively inaccurate themselves, (2) statistically effective and flexible methods for employing historical flood data in flood frequency investigations, (3) consistent and straightforward treatment of low outliers, and (4) computation of confidence intervals for quantiles correctly reflecting uncertainty in the skewness coefficient. A computational study demonstrates how Bulletin 17B confidence intervals (correctly computed for known skew) perform when the weighted skew is estimated with at‐site and regional information.

back to top

HYDROLOGIC ANALYSIS AND WATER RESOURCES

Select this Article		Even When It Rains You Need to Drought Plan: Dynamic Modeling Application to Water Supply Planning in Virginia J. Timothy Hare, P.E., James Spacek, P.E., Laurens van der Tak, P.E., and Edwin Snyder, III, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)206 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract CH2M HILL working with the City of Portsmouth conducted a Water Supply Master Plan Study that includes evaluation of the safe yield of the City's reservoirs, evaluation of water quality and treatment issues, and development of system‐operating rules. The purpose is to develop an integrated water supply plan that both supports new state requirements as well as assists the City in making decisions involving the future direction of water supply and water sales development. The new state regulations call for “Water Plans” to be developed. Requirements for the Water Plan include an assessment of needs and current supplies, development of a Drought Response and Contingency Plan, description of demand management measures in place and articulation of a Statement of Need. This paper will describe CH2M HILL's efforts to assist the City of Portsmouth in developing its Water Plan, including the application of the dynamic simulation model VOYAGE. One major part of the work involved the development of the drought response plan and reservoir operating rules. The foundation for both the plan and the rules was the testing of different reservoir operating modes. The operating modes consisted of different combinations of withdrawal rates, reservoir routing, and groundwater well pumping. The two limiting factors considered were available useable storage in the reservoirs and fluoride levels in the finished water. Each operating mode was modeled and optimized using CH2M HILL's water system simulation model VOYAGE. This tool is an object oriented model created in the Extend simulation platform. VOYAGE was designed to quickly evaluate numerous potential solutions and identify the optimal combination of water supply sources to meet demands based on given constraints and the operation that will optimize system performance. Input to the model included system configuration data, plant upgrade scenarios, water usage, meteorological data, and the results of an unaccounted‐for water study. Twelve mode of operation scenarios were tested using a weekly time step over a four year period that included the 2001 – 2002 drought. The scenarios were divided into three groups. The first group assessed the combination of existing surface supplies and production wells. The second group included only wells as the raw water source during drought. The third group added an emergency pipeline from a neighboring reservoir owned by the City of Norfolk. VOYAGE allowed fast evaluation of changes in operating rules, for example, comparing the advantages of releasing water from upstream reservoirs based on total useable volume of the reservoir system with releases based on only the downstream reservoir's useable volume. Other modes of operation tested the optimal trigger points for well activation during a drought as well discharge location within the system. Efficacy was based both on available water for withdrawal and water quality at the intake.

Select this Article		Development of Depth‐Duration‐Frequency Relationships Using Homogeneous Region Concept John P. Raiford, Nadim M. Aziz, and Abdul A. Khan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)207 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This study presents an attempt to develop depth‐duration‐frequency curves for a region including South Carolina, North Carolina, and Georgia by identifying homogeneous regions. Existing methodologies of identifying the homogenous regions are reviewed and utilized in this study. The aim of the study is to update the existing intensity‐duration‐frequency curves and develop isopluvial maps that can be used to develop these curves at ungauged sites throughout the region. For this study, 17 durations ranging from 15 minutes to 120 hours are analyzed. For each duration, return periods of 2, 10, 25, 50, and 100 years are considered. Data is collected from various sources and the missing daily data is estimated using the surrounding daily stations. Maximum annual precipitation series is computed for each duration at each site. The scale correction factor is applied to correct the maximum precipitation data for clock hour interval recording. The serial and cross‐correlation of maximum annual precipitation series are computed to verify the assumption that rainfall is independent of time and space. Outliers in the maximum annual precipitation series are identified and removed. The impact of missing periods on outliers is also investigated. The maximum annual precipitation data at each site is also fitted to candidate probability distributions in order to determine rainfall amount for each return period and duration. The distributions used for this study are normal, lognormal, generalized extreme value, Pearson type III, and log Pearson type III. The goodness‐of‐fit of each distribution is evaluated with the chi‐squared goodness‐of‐fit test to choose the best fit. Isopluvial maps are developed by performing spatial analysis. The intensity‐duration‐frequency curves are developed and compared to the existing curves.

Select this Article		Hydrology as a Surrogate Indicator in Restoring Urban Northeastern Watersheds Tham Saravanapavan, Mark Voorhees, and Andrew Parker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)208 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Habitat/aquatic impairments in an urban environment are often associated with multiple stressors, including known and unknown pollutants, storm water runoff, hydrologic modifications, riparian corridor encroachment, and channel alteration. These stressors may be acting either individually or cumulatively. In the absence of comprehensive physical, chemical, and biological data it is often difficult to determine each stressor's role and significance in contributing to the impairment. As a result, developing restoration plans or TMDLs and implementing improvements to address these impairments presents unique and complex challenges. This paper presents an approach to restoration plans or TMDL development and implementation planning for data‐limited urban watersheds using a manageable watershed model and a flow analysis. Evaluation of data in many New England watersheds has shown that habitat/aquatic impairments are frequently related to excessive urban development and the accompanying increased storm water runoff. Not only does the storm water runoff regime (including changes in the peak and base flows) alone lead to problems, but increased runoff also generally leads to increased pollutant transport capacity and loading. Therefore, using storm water as an “umbrella” surrogate to address a suite of stressors contributing to aquatic life impairments is a plausible option in urban areas (where discrete local problems have not been identified). The use of surrogate indicators expressed as quantitative targets is an important tool for developing TMDLs. This paper demonstrates application of simple watershed models to support flow duration analysis and hydrologic target identification for TMDL development in Maine, Vermont, and Massachusetts. It also exemplifies how the approach can be extended to support storm water implementation planning.

Select this Article		Impact of New Rainfall Patterns on the Design of Hydraulic Structures David N. Powell, Nadim M. Aziz, and Abdul A. Khan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)209 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The current SCS dimensionless rainfall distribution patterns (Type I, IA, II, and III) are thought to be over conservative and in need of replacement. This study develops new dimensionless design rainfall patterns for the state of South Carolina for various durations. The rainfall data from various sources dating back to 1971 was collected and analyzed. Different storm separation methods were reviewed and a modification of an existing method was adopted for the study. The rainfall events were combined into 21 different groups ranging from 2 to 51 hours. The top fifty events (by volume) within each group were selected to determine the dimensionless rainfall pattern. Similar dimensionless rainfall patterns for various groups were combined to create representative time‐duration patterns for the state of South Carolina. The results showed that two distinct dimensioless rainfall patterns could be established. The new rainfall patterns were compared to the SCS rainfall curves and rainfall patterns developed by other states. The impact of these new dimensionless rainfall patterns on design practice was assessed. The new rainfall patterns were used to evaluate the response of hydraulic structures to rainfall events. In particular, the basin rainfall‐runoff volume and detention pond performance were evaluated and compared to the results from the SCS rainfall patterns. For the basin test, the runoff volume, peak discharge, and time to peak were compared. For the pond test, the stage versus time and the ratio of storage volume to runoff volume were compared. The impact of varying the outflow culvert size on pond storage requirement was also investigated. The comparison showed that new rainfall patterns resulted in lower peak flow and different peak time for the runoff hydrograph. The new rainfall patterns resulted in lower peak stage and detention pond storage volume.

back to top

HYDROLOGIC IMPACTS AND ANALYSIS

Select this Article		Drinking Water Surveillance of a Growing Community in Osun State, Nigeria S. O. Omojola, E. A. Olanipekun, and J. A. Ayangade ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)210 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This study focuses attention on the examination of the quality of drinking water in Ipetumodu and Yakoyo Communities in Ife North Local Government Area of Osun State, Nigeria. Based on the population, geographical spread and physical observations, structured questionnaires were administered on the residents to determine the various drinking water sources. Nine sources of drinkable water were identified and samples were taken from them to determine their physical, chemical and bacteriological characteristics. The Physical analysis revealed total solid and^turbidity values (of the sampled water) of 100mg/L–860.0mg/L, and 3.5NTU–20.5NTU respectively. The chemical analysis shows hardness, alkalinity, P^H and chlorides values of 13.5mg/L–270.2mg/L, 3.5mg/L–21.2mg/L, 6.3–8.5 and 10.0mg/L–20.0mg/L respectively while the bacteriological analysis revealed the absence of coliform in the water samples collected from three out of the nine drinkable water sources. The paper concluded that imminent outbreak of water borne diseases can not be ruled out and it recommended that both the Local and State Government should work harmoniously towards ensuring the provision of potable water to the nook and crannies of the state because health is wealth.

Select this Article		Hydrologic Impact of the 2004 Hurricane Season on South Florida Wossenu Abtew and R. Scott Huebner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)211 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract South Florida was hit by one hurricane, two major hurricanes, and a remnant of a fourth hurricane in less than a seven‐week period in 2004. Hurricanes Charley, Frances, and Jeanne along with remnants of Hurricane Ivan had hydrologic impact on South Florida. A similar series of events had not been observed in records dating back to 1871. The property losses from these hurricanes were extremely high. High rainfall, high surface water flows and a rise in lake water levels were experienced. Most of the rainfall occurred on the Upper and Lower Kissimmee Basins, the headwaters of Lake Okeechobee, which is the central component of the South Florida water management system. In these basins, the 100‐year return period of monthly rainfall was observed for September 2004. The resulting surface water flow raised the water level in Lake Okeechobee, a 175,304 ha lake, by 1.64 m between August and October 2004 resulting in a storage increase of 292,347 ha‐m. It impacted surface water management in South Florida. This paper presents an analysis for the individual and combined hydrologic impacts of the 2004 hurricanes on South Florida.

Select this Article		Riparian Buffer Zone Change Detection Based on RADARSAT‐1 and LANDSAT Satellite Images A. Drunpob and N. B. Chang, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)212 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A combination of RADARSAT‐1 and Landsat 5 TM satellite images linking the soil moisture variation with Normalized Difference Vegetation Index (NDVI) measurements were used to accomplish remotely sensed change detection of riparian buffer zone in the Choke Canyon Reservoir Watershed (CCRW), South Texas. The CCRW was selected as the study area contributing to the reservoir, which is mostly agricultural and range land in a semi‐arid coastal environment. This makes the study significant due to the interception capability of non‐point source impact within the riparian buffer zone. First of all, an estimation of soil moisture using RADARSAT‐1 Synthetic Aperture Radar (SAR) satellite imagery was conducted. With its all‐weather capability, the RADARSAT‐1 is a promising tool for measuring the surface soil moisture over seasons. The time constraint is almost negligible since the RADARSAT‐1 is able to capture surface soil moisture over a large area in a matter of seconds, if the area is within its swath. RADARSAT‐1 images presented at here were captured in two acquisitions, including April and September 2004. With the aid of five corner reflectors deployed by Alaska Satellite Facility (ASF), essential radiometric and geometric calibrations were performed to improve the accuracy of the SAR imagery. The horizontal errors were reduced from initially 560 meter down to less than 5 meter at the best try. Then two Landsat 5 TM satellite images were summarized based on its NDVI. The SAR data obviously show that soil moisture and vegetation biomass wholly varies in space and time in the CCRW leading to identify the riparian buffer zone evolution over seasons. It is found that the seasonal soil moisture variation is highly toed with the NDVI values and the change detection of buffer zone is technically feasible. Future research focuses on comparison of soil moisture variability within RADARSAT‐1 footprints against NDVI variations for studying riparian ecosystem functioning on a seasonal basis. It will contribute to develop more effective management strategies for non‐point source pollution control, bird habitat monitoring, and grazing and live stock handlings in the future.

Select this Article		A Hydrologic Analysis on Inundation in the Flooding Area of the Mekong Delta, Cambodia: The Combined Deterministic and Stochastic Models for Flood Forecasting K. Sothea, A. Goto, and M. Mizutani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)213 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Since the watershed of the Mekong River is situated under the typical monsoon climate, the Mekong River presents a distinct variation in its water levels between the dry and rainy seasons, and causes heavy inundation in the Delta area along the river every year. In order to analyze the flow phenomena and inundation process for agricultural practice in the Mekong Delta, this study tried to establish three models: the combine of “3∗4+1‐type” model and the ARMA time series model, Tonle Sap Lake Storage Model and Delta Water Balance Model. The “3∗4+1‐type” Model was employed to calculate the runoff of the Lower Mekong River Basin from Chiang Saen to Kompong Cham and its sub catchments. The ARMA time series model was applied to the residuals of the Tank Model application in order to obtain 1 day to 5 days ahead flow forecasting after the present day based on the available data of the present day. The inflow to the Tonle Sap Lake was also estimated by the “3∗4+1‐type” Model, whereas outflow of the lake was formulated based on the relationship between storage volumes and water level of the Lake surface. The application of the ARMA to the “3∗4+1‐type” model was found effective to improve flood forecasting at the outlets point of each sub‐catchment. The established storage model for the Tonle Sap Lake could calculate well for simulating the outflow and the seasonal water balance of the Tonle Sap area. Deltaic area was divided into four zones, and water balance of each zone was formulated by considering the zone's inflow/outflow between rivers and flooding areas. The establishment of these three models could provide a basic framework for modeling the Mekong Delta, Cambodia.

back to top

HYDROLOGIC MODELING

Select this Article		Development of Stage-Discharge Relation Using Support Vector Machines Mahesh Pal and Arun Goel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)214 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Establishment of rating curves are often required by the hydrologists for flow estimates in the streams, rivers etc. Measurement of discharge in a river is a time-consuming, expensive, and difficult process. Furthermore, the conventional approach of regression analysis of the stage-discharge relation does not provide encouraging results especially during the floods. Therefore, present study is aimed at the application of support vector machines (SVM) based algorithm for modelling stage-discharge relation including the hysteresis effect. A data set of discharge-measuring station located on an Indian river has been used for analysis in the present study. A back propagation neural network model was also employed on the same data in order to compare the performance of the results based on support vector machines based modelling technique. The outcome of the study suggest that the support vector machines works quite well for both the data sets and produced promising results in comparison to the neural network technique. Finally, results also suggest the suitability of SVMs algorithm in predicting the looped rating curve having hysteresis effect as well.

Select this Article		Improving Hydrologic Model Performance by Using the UNET Model: A Case Study for the Illinois River Basin Yanqing Lian, Ph.D., Hua Xie, Misganaw Demissie, Ph.D., P.E., and H. Vernon Knapp ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)215 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Using the U.S. Environmental Protection Agency's (USEPA) Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) system, the Illinois State Water Survey developed a Soil Water Assessment Tool (SWAT) model for the Illinois River basin. The SWAT model was calibrated and verified using observed flows at Marseilles, Kingston Mines, and Valley City along the Illinois River. Over the 1993‐2000 simulation period, Nash‐Sutcliffe efficiencies for daily, monthly, and annual flows exceeded 0.7 at the three gaging stations, except daily flows at Kingston Mines. However, comparisons between the simulated and observed daily flows indicated that simulated and observed peak flows deviated in magnitude and timing. The SWAT model uses Muskingum and variable storage‐flow routing schemes, which are less capable of routing flows in the complex Illinois River that has locks and dams, backwater lakes, and gentle hydraulic gradients with backwater effects from the Mississippi River. The goal of this study was to improve the hydrologic modeling accuracy for daily flow routing on the Illinois River. A one‐dimensional unsteady state hydraulic model (UNET) developed for the Illinois River was coupled with the calibrated SWAT model. This paper compares modeling accuracies of the coupled SWAT‐UNET models and SWAT model results.

Select this Article		Effect of Digital Elevation Model (DEM) Resolution on the Hydrological and Water Quality Modeling Ramesh S. V. Teegavarapu, Chandramouli Viswanathan, and Lindell Ormsbee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)216 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The resolution of digital elevation model (DEM) used for watershed delineation and data extracted from the delineated watershed relevant to hydrography plays an important role in the calibration of hydrological models. The effect of DEM resolution on the drainage length, watershed area and average slope are studied in many earlier works. DEM resolution can have impact on hydrologic modeling parameters, water quality simulation results. The impacts of DEM resolution on results of the watershed response and water quality modeling are studied using HSPF (Hydrologic Simulation Program Fortran) model applied to a watershed in Kentucky in this study. Three major streams in this watershed are impaired due to pathogen pollution according to the current state of Kentucky water quality standard set for recreation. The effects of DEM resolution on water quality modeling and calibration for fecal coliform bacteria are studied using a HSPF model. Results from this study indicate that the DEM resolution affects hydrography parameters of the delineated watershed, influence the calibration process, and the non‐point and point source loadings to the streams in the watershed.

Select this Article		Stochastic GIS‐Based Water Resources/Quality Modeling of the Land Water Interface A. M. Salah and E. J. Nelson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)217 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Linking a land model to a water model at this interface is a major step in developing an integrated water quantity/quality modeling process. On the other hand, the quantification of variability and uncertainty of hydrology and water quality parameters is a great challenge facing water resources managers. The objective of this paper is to.report on the use of the Gridded Surface Sub‐surface Hydrological Analysis (GSSHA) and CE‐QUAL‐W2 model interfaces in the Watershed Modeling System (WMS) as a framework for an integrated water resources approach that can stochastically model the land water interface. The conventional integrated water resources methods are primarily based on deterministic approaches. Whereas this research uses some statistical methods to address uncertainty and account for the randomness of model input variables. WMS is a comprehensive graphical modeling environment for various phases of watershed hydrology. It is a GIS‐based pre/post processing software that supports many hydrologic/hydraulic and water quality models widely used by water resources managers/engineers. GSSHA is a 2d physical, distributed hydrologic model that simulates the hydrologic response of a watershed subject to given hydrometeorological inputs. CE‐QUAL‐W2 is a two‐dimensional water quality and hydrodynamic model capable of modeling watersheds with interconnected rivers, reservoirs and estuaries. The framework presents modeling the land portion of the watershed using GSSHA and taking the GSSHA output to use as input to CE‐QUAL‐W2. This process is repeatedly done using statistical simulation for GSSHA input parameters using probability density functions (PDFs) of selected parameters that are assumed to exhibit a probabilistic nature. Furthermore, the presented framework addresses uncertainty in both water quantity and quality. Statistical intervals are used to report results as opposed to single value. For example, a time series of a pollutant of choice is presented in a credible interval of, for instance, 95% confidence level would suggest there is a 95% probability that the pollutant lies between the interval limits. This is as opposed to reporting a single concentration value for each time step.

back to top

PRECIPITATION AND RUNOFF CHARACTERISTICS AND MODELING

Select this Article		Isopleths for Rainfall Data in Sabah V. J. Kurian, J. K. Febik, N. Bolong, and I. Zakaria ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)218 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Isopleths are lines along which rainfalls have the same specified intensity. These isopleths form the basic information needed for the design of systems needed for roof drainage, urban drainage, water supply, irrigation and flood control. Hence they are very important for ‘water management’. For the design of roof drainage systems, rainfall data for short durations such as 2 minutes, 5 minutes, 10 minutes & 15 minutes are needed for return periods of 50 and 100 years. In Sabah State of Malaysia (Part of Borneo Island), from 1960 to 1984, only few stations were recording rainfall and that too only daily rainfalls. So, the minimum duration data available was only for 1 day. From 1985 onwards, the data for 5 minutes, 15 minutes, 30 minutes, 60 minutes & 120 minutes have been recorded along with daily rainfall. The available rainfall data is only for 19 years from 1985 to 2003. Based on these available data, rainfall data for longer return periods such as upto 100 years are predicted using multiple regression analysis of exponential type. The equation used is P = KT^at^bT₁^cP₁^d where P is the rainfall in mm, T is the return period of P in years, t is the duration of P in minutes, T₁ is the return period of P₁ in years, P₁ is the daily rainfall in mm and K, a, b, c, d are constants. After completing the Intensity − Duration − Frequency (IDF) curves for 52 stations & using these data, isopleths for storms of duration 5 minutes for return periods of 20 years, 50 years & 100 years are plotted. Using these isopleths, it would be possible to estimate the design rainfall for any location in Sabah.

Select this Article		Regional Frequency Studies of Annual Extreme Precipitation in the United States Based on Regional L‐Moments Analysis B. Lin, G. M. Bonnin, D. L. Martin, T. Parzybok, M. Yekta, and D. Riley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)219 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The paper discusses an L‐moments based regional rainfall frequency approach and its application in large areas with many regions and across a broad range of durations. Advantages of the technique in terms of robustness to outliers and stability of quantile estimates are demonstrated through real examples. This paper provides an overview of NOAA Atlas 14, the updates of the rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration's National Weather Service for the Semiarid Southwest United States and the Ohio River Basin and surrounding states, focusing on technical/statistical aspects and developments and findings during the studies, such as (1) the criteria for identifying and verifying homogenous regions in a large area, (2) the goodness‐of‐fit for comparison and identification of distributions to best model the data in a region, (3) the concept of the real‐data check and its use in regional frequency analysis, (4) consistency adjustments over a broad range of durations from 1‐hour to 60‐days, (5) identification of intersite dependence of the annual extreme precipitation and its impact on quantile estimates, (6) confidence limits as an uncertainty measure of the quantile estimates and, (7) the ratios of Partial Duration Series quantiles to Annual Maxima Series quantiles.

Select this Article		Investigating Urban Land Use Effects on Runoff by Using the Distributed Large Basin Runoff Model J. R. Cowden, D. Watkins, and T. E. Croley, II ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)220 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Urbanization is a growing trend world wide and presents many significant challenges in watershed planning. Distributed operational hydrology models can assist decision‐makers in understanding the effects of land use and urban development policies on large watersheds, including runoff quantity and quality. The National Oceanic and Atmospheric Administration's Great Lakes Environmental Research Laboratory (GLERL) has developed the Distributed Large Basin Runoff Model (DLBRM) as a large‐scale model for the Great Lakes basin. This paper illustrates how the daily DLBRM may be used to model runoff impacts of urbanization. Urbanization trends within the Clinton watershed of Southeastern Michigan are discussed, including analysis of stationary stream flow trends of the watershed. Calibration issues regarding temporal parameter variability are also addressed followed by urbanization scenario simulations within the Clinton watershed.

back to top

RIVER HYDROLOGY AND HYDRAULICS

Select this Article		Investigation on Changes of the Sakarya River Characteristics Sabahattin Isik, Mustafa Sasal, and Emrah Dogan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)221 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract After construction of dams, the hydrologic and hydraulic characteristics of rivers change drastically. Many researchers investigated these changes, affecting services and structures. The changes of river flow and sediment transport cause riverbed scour at downstream section. In this study, changes in the Lower Sakarya River are investigated after construction of Gokcekaya Dam in the Middle Sakarya Basin. Furthermore, gravels have been withdrawing from the Lower Sakarya River especially within 5 decades in order to meet construction materials for the surrounding large cities. Changes of expected probable floods are determined by using annual maximum discharges at both same stations. It is noticed that as the flood peak discharge decrease, the river flow regime is regulated. Sediment rating curves are determined and compared by using measured suspended load for before and after the dam. It is observed that the sediment transport was decreased at a rate 40–65 % after the Gokcekaya Dam.

Select this Article		Classification of River Yields in Turkey with Cluster Analysis Sabahattin Isik, Aydin Turan, and Emrah Dogan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)222 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Clustering is necessary for lack of data in a basin based on hydrometeorological homogeneity. Even principal characteristics of river basins, such as; climate, geology, and topography affecting water yields are different, some of them yield similar hydrologic outcome. In this study, 1410 stations of Turkey Rivers were classified by the cluster analysis on the basis of hydrological homogeneity. Monthly average yields (m³/s/km²) of 1410 river gauge stations on 26 river watersheds were used. It is aimed that the clusters to be homogeneous, the elements of the same cluster to be similar while they are not similar to those of a different cluster and the most meaningful groups to be made. The cluster number was found by using the agglomerative hierarchical cluster analysis method. Tests were conducted that stations from different geographic locations are considered in the same cluster independent of their geographic position. Turkey river basins were separated into 6 homogeneous regions and the yield distribution map of Turkey was obtained.

Select this Article		Comprehensive Watercourse Management for the Menomonee River, WI: Milwaukee County Grounds Floodwater Facility Michael Schwar, Ph.D., P.E., M. ASCE, Tom Chapman, P.E., Ronald J. Printz, P.E., Michael Hahn, P.E., and Joshua M. Kasun, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)223 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract As a key part of an integrated floodwater management project, the Milwaukee County Grounds (MCG) Floodwater Facility has been designed in conjunction with downstream levee systems to sufficiently reduce water levels on the Menomonee River to provide a 100‐year level of protection to previously flood‐prone urban areas. The MCG facility functions by intercepting high flows from Underwood Creek, a major tributary of the Menomonee River, that would otherwise drive peak downstream water levels. Although the performance of the facility was designed and confirmed using a series of design events, each with different rainfall characteristics, the regulatory determination of flow reduction is based on continuous simulation hydrologic modeling using the Hydrologic Simulation Program — FORTRAN (HSPF). The urban setting of this project, the strategy required to reduce flood flows and the sophisticated modeling required to assess project performance all provided challenges to the MCG facility design. The project design has been completed and site regrading has been initiated. Project infrastructure will be constructed beginning in 2008 under a separate contract. Upon completion the MCG facility will reduce downstream flows sufficiently to remove 175 structures from the regulatory floodplain and likely save millions of dollars in flood damages.

Select this Article		Hedging Rule and Its Relevance to Decision Making in Reservoir Operation Jiing‐Yun You and Ximing Cai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)224 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hedging rule for reservoir operation is used for rationing water supply. It accepts a small deficit in current supply so as to reduce the probability of a more severe water shortage. Recently, the community of water resources planning and management has started emphasizing the value of hedging rule because of growing water demand and increasing uncertainty in water sources. Although the concept is straightforward, the lack of the foresight of reservoir inflow makes it technically difficult to analyze. Uncertainty or imperfect information plays a very important role in hedging rule. However, few studies considers uncertainty in hedging rule analysis. This study develops a theoretical analysis of hedging rules for reservoir operations with consideration of uncertain reservoir inflow. Our approach is currently limited to a two‐period optimization model (now and then) for a single reservoir, which is to maximize the utility over the two periods. General results have been derived for the following questions: (1) What is the timing for implementing hedging rules (when will it start and end)?, (2) When is a hedging rule trivial?, (3) What is the impact of the inflow uncertainty in the second period?, and (4) What is the impact of reservoir evaporation on the significance of a hedging rule? Moreover, a numerical model is developed to verify the conclusions from the theoretical analysis. The model specifies a certain type of utility function and represents the inflow uncertainty through a probability distribution function, and includes engineering constraints such as reservoir capacity and water withdrawal capacity. Therefore, the numerical model can be used to show more detailed analyses on price elasticity, uncertainty, and engineering capacities, which are difficult to include in the theoretical analysis.

back to top

CHINA I

Select this Article		Rubber Dam in China Gao Benhu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)225 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper interprets the characteristic of rubber dam, introduces the rubber dam development and application in China, and discusses the expectation of rubber dam.

Select this Article		Study of Eco‐Environment Monitoring in Arid Area Based on Multi‐Source Multi‐Temporal Remote Sensing Images and GIS Lin Li and Jingxuan Lu, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)226 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The ecological environment which human existence depends on is more and more under threat due to our own over consumption of water resources. Desertification of land and shrinkage of oases are ubiquitous in droughty area. Various structural and non‐structural measures have been taken to hold back such environment deterioration, such as peremptory water transfer. In this paper the downstream region of the Tarim River has been.chosen as the test area. In the 7^th decade of the last century, many reservoirs were built on the upstream of the river for irrigation purposes. Due to the increased water diversion on the upstream, river flow disappeared on the downstream and the downstream natural conditions became worse since then. The river basin authority then decided to send water downstream through compulsory means to protect the downstream eco‐environment. Water from upstream reservoirs and lakes has been diverted to downstream several times since 2000. In order to evaluate changes of the downstream eco‐environment before and after the water transfer, especially changes in the size and vegetation cover density of the downstream oasis, analysis was conducted in this study. Remote sensing is found to be an efficient tool in such investigation due to its multi‐resource and multi‐temporal characteristics. Image data collected from MSS, TM, CBERS‐2 and MODIS are used to study the land cover changes. Through overlaying and buffering analysis in the GIS platform, a relationship between vegetation and water resource has been established. The result will be of significance to more efficient natural environment protection and more reasonable water resource allocation for this river basin in the future.

Select this Article		Crop Type Change Monitoring by Remote Sensing in an Irrigated District under Water Resources Restrictions Mei Xu, Jingxuan Lu, Ph.D., and Benqing Ruan, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)227 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, the Qingtongxia irrigated area of Ningxia Hui Autonomous Region of China will be used as the study area. The local agriculture depends absolutely on irrigation because of rare rainfall and very dry climate conditions. It is located in the upstream of the Yellow River. In the last few decades, the irrigation area has enlarged a lot under the encouraged land reclamation policy. Serious land salinization problem has been resulted due to the local custom of wasting irrigation. A lot of water was diverted for agriculture. The situation has changed since 2000, however, because the permitted water volume to be diverted from the Yellow River for this district was reduced to about 60% of the former actual water diversion due to the implementation of the water resources reallocation program along the whole Yellow River basin. Under such situation, this irrigated area was forced to adjust their crop planting patterns for water saving purposes. In this study, the evolution process will be monitored using remote sensing technology. Result shows that three aspects of the water resources related problems can be reflected clearly. It is found that new cultivated land has increased a lot in nearly twenty years time. Land salinization problem is also serious due to long time high groundwater level and strong evaporation. Results also show that the irrigated area has adjusted a lot to reduce its irrigation water diversion. It is clearly shown that area of the high water consumption crop such as paddy has reduced, while that of low water consumption crop such as wheat and corn increased more since 1999. It is hoped that the result can help the irrigation manager to make more reasonable irrigation plan in the future. The result will also be of positive meanings to the whole Yellow River basin that will face with long‐term water‐saving requirement.

Select this Article		RS‐Based Evaluation of Water Re‐Allocation and Eco‐Environment Evolution in an Arid Natural Oasis Jingxuan Lu, Ph.D., Hongmu He, Shaonan Zhong, and Lin Li ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)228 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Ejina natural oasis, located on the downstream delta area of the inland Heihe river basin, is surrounded by gobi and desert and featured by poplar forest. It has been under serious threat of water shortage and eco‐environmental deterioration starting from the late 1950's, especially from 1980's, due to over agricultural water diversion at the middle reach. Water into the oasis became less and less since then. A whole basin trans‐provincial water allocation program, as the first step, has been implemented since 2000 to hold back the rapid withering trend of the oasis as quick as possible. A three year emergent water saving and environment protection project, as the second step, was also carried out during 2001 to 2003. This has directly resulted in a step by step increase of water volume into the oasis during the last five years. In this paper, two questions regarding the evolution of the oasis eco‐environment during the past two decades will be answered using multi‐temporal satellite images. The first question is how fast the oasis had withered from the middle 1980's. The second question is to what extent the oasis has recovered from 2000 to present. Based on the results from remote sensing analysis, the relation between water reallocation and eco‐environment evolution will be assessed.

back to top

CHINA II

Select this Article		Middle Route Project of South‐to‐North Water Transferring Zi‐hui Liu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)229 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Middle Route Project of South‐to‐North Water Transfer is the backbone project for sustainable development of North China. This paper put forwards the necessity and the main features of the project. It is emphasized that the basic law of the project planning and designing is benefit to both the water supply area and water diverted area. How to put into practice this law is the main line of this article. China features large in territory and great different natural climate condition. The spatial distribution of water resources is uneven and non‐coordinated with the national economic layout of China. Since 1980s, water resources shortage has became more and more serious in a larger scope with economic development. Along with the concept setting up of water being as a kind of resources, great progress has been achieved in water saving area. According to the statistical data, from 1980 to 1997, GDP of China increased by 7.4 times, reached to 11000 billion RMB, but water use increased by 25%, the water saving potential capacity has been greatly developed. Chinese economy is being in high‐speed development, water resources demand will still increase. This requires us in one hand to develop water saving potential capacity and more in another hand to transfer water in a long distance by means of market and government macro regulation and control, for solving fundamentally water resources shortage problem.

Select this Article		The South to North Water Transfer Project of China Jinshan Mei ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)230 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The south of China has more water while north has less. In order to solve water shortage in Huang‐Huai‐Hai River Basin, the South‐to‐North Water Transfer Project will be built to deliver water separately from the upper, middle, lower reaches of the Yangtze River. The South‐to‐North Water Transfer Project is composed with the three routes, East Route, Middle Route and West Route, which can be connected to from a huge network with “four transverse and three longitudinal waterways” with such four rivers as the Yangtze River, Yellow River, Huai River and Hai River. The implement of the first stages project of East Route and Middle Route can promote carrying capacity of water resources and environment in water receiving areas, promote the efficiency of resources dispatching, the strategic adjustment of economy structure and reserves for economic development, inhibit and gradually improve the deteriorating ecological environment and ensure the sustainable development of economy, society and environment. China is a country short of water resources. Although the total amount of water resources reaches 2812.4 billion m³, per capita is only about 2100 m³, one‐fourth of the world average, due to the large population. Moreover water resources are unevenly distributed in both space and time, and water resources are incompatible with combination of other resources. Therefore, appropriate allocation of limited water resources for raising water use efficiency is a very important issue for China's social and economic sustainable development. According the layout character of water resource in our country, Chairman Mao Zedong put forward a great idea on October 30, 1952, that since there is more water in the south than in the north, it is desirable to transfer some water if possible. Since then, under the lead and care of the Party Central Committee and State Council a large number of scientific and technical people have made preparation for the South‐to‐North Water Transfer Project during the past 50 years, during which lots of investigation and survey have been done. Based on comparison of so many alternatives, a fundamental scheme composed of the east, middle and west routes has been developed and lots of valuable results have been obtained. In Dec, 2002, The General Program of the South‐to‐North Water Transfer Project was approved by the State Council. Now some of the works of the first stage of East Route and Middle Route have been under construction.

Select this Article		Virtual Versus Real Water Transfers within China Jing Ma, Arjen Y. Hoekstra, Hao Wang, Ashok K. Chapagain, and Dangxian Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)231 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract North China faces severe water scarcity — more than 40% of the annual renewable water resources are abstracted for human use. Nevertheless nearly ten percent of the water used in agriculture is applied for producing food exported to South China. To compensate for this ‘virtual water flow’ and to reduce water scarcity in the North, the huge South‐North Water Transfer Project is currently being implemented. This paradox, transfer of huge volumes of water from the water‐rich South to the water‐poor North versus transfer of substantial volumes of food from the food‐sufficient North to the food‐deficit South, is receiving increased attention, but the research in this field stagnates at the stage of rough estimation and qualitative description. The aim of this paper is to review and quantify the volumes of virtual water flows between the regions in China and to put them in the context of water availability per region. The analysis shows that North China annually exports about 52 billion m³ of water in virtual form to South China, which is more than the maximum proposed water transfer volume along the three routes of the Water Transfer Project from South to North.

Select this Article		Water Marginal Benefit Analysis in the Recipient Area of Water Transfer Project from South to North Dangxian Wang, Jing Ma, Hao Wang, Yin Wang, Jianshi Zhao, and Bifeng Shen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)232 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Huang‐Huai‐Hai River Basin, the recipient area of Water Transfer Project, is one of the most water‐scarce territories in the world. Water resources already became the key factor to tie up the socioeconomic development. Therefore, to quantitatively analyze its contribution to national economy will be an important reference for the huge water diverting project evaluation. This paper calculates the output elasticity and marginal benefit of water by establishing Cobb‐Dauglas production function for Huang‐Huang‐Hai and whole nation. The result shows the marginal benefit of Huang‐Huai‐Hai including agriculture is around 2.9yuan/m³, excluding agriculture is around 13.2 yuan/m³, which is higher than national average value. It can be predicted that the water marginal benefit will increases as scarcity of water, correspondently the GDP losses by water shortage will be intensified. Thus, implementing the diverting project will be a wise way to diminish the loss.

back to top

CHINA III

Select this Article		Key Technologies for Urban Flood Mitigation Ximin Yuan, Changwei Hu, Yanyan Wang, Hongpin Zhang, and Hongtao Wan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)233 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper is concerned about the following problems: (1) Flood simulation for urban areas based on compound models of 1‐D and 2‐D hydraulic models, (2) Flood losses estimation and assessment by applying hydrological and hydraulic approaches, and (3) Application of advanced information technologies in flood simulation, information visualization and system integration, such as GIS, WEB, Database and Flash, etc. Case studies have been done for some Chinese cities, such as Shanghai, Hangzhou, Beijing etc.

Select this Article		Using RVA to Determine the Feasible Draft of Main Tunnel of the Diversion Work from the Datong River to the Huangshui River Zhao-dong Sun, Fu-qin Hao, Ren-xiang Wang, Rui-lan Shi, Jian-guo Zheng, Yong-feng Liu, Ai-xiang Li, and Yi-juan Ma ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)234 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In the northwest of China, the Qinghai province intends to construct a main tunnel to divert water from the upper Datong River to the Huangshui River. In order to determine the feasible diversion of the main tunnel, a diversion dam operation model is established employing varying design diversion as one of its inputs and the Range of Variability Approach (RVA) is used. Results shows that the diversion in the upper Datong River must not exceed 377 million cubic meters that is about 23.86% of 1.58 billion cubic meters, mean annual runoff of the upper Datong River under the case not diverting water in December, January and February, which is much less than 1422 million cubic meters suggested in 1997. The mean annual diversion of the main tunnel can reach 284 million cubic meters that is about 17.97% of annual runoff of the upper Datong River.

back to top

CHINA IV

Select this Article		Importance of Soil and Water Conservation and Ecological Environment Protection in Key Hydraulic Projects and Hydropower Stations Construction on Chinese Great Rivers Gao Xubiao and Jiao Junren ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)235 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Since reform and opening, especially since entering the new century, economy in China has maintained a rapid and healthy development and more and more key hydraulic projects and hydropower stations have present the characteristics of rapid speed, short period and good benefits, but at the same time, they also have bought new challenges for soil and water conservation and ecological environment protection. In the late 1990s, China has instituted a set of laws and regulations on soil and water conservation and ecological environment protection to reinforce environment management in development and construction projects. We were implementing ecological environment construction engineering of soil and water conservation at the same time when the Three Gorges Hydraulic Project on the Yangtze River, Xiaolangdi and Wanjiazhai Hydraulic Projects on the Yellow River, Dachaoshan Hydraulic Project on Lancang River and other key hydraulic projects and hydropower stations were being constructed, and have achieved notable effects. The common characteristics of the soil and water conservation and ecological environment construction of the main key hydraulic projects are: First, making water and soil conservation plans and its special designs at the beginning of major project design. Second, implementing prevention‐control measures of water and soil loss when the project was under construction. Third, accepting major project consisted of special acceptance of water and soil conservation engineering, performing the national requirements of the “three‐simultaneity” system between the construction and development projects and the water and soil conservation very well.

Select this Article		Preliminary Study on the Classification and Types of Preferential Flow in the Dark Coniferous Forest Ecosystem of Gongga Mountain Jianzhi Niu, Ph.D., Xinxiao Yu, Ph.D., Lihua Chen, Ph.D., Liangyi Rao, Ph.D., and Yutao Zhao, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)236 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Preferential flow indicates that an ordinary phenomenon of rapid and non‐equilibrium transport of water and solutes happens in most of soil. It causes a latent pollution of ground and surface waters and affects runoff yield and concentration. This paper studies the preferential flow movement of the dark coniferous ecosystem of Gongga Mountain, sets up the classification of the preferential flow and discusses the types of preferential flow in the reached area. Results show that the perceptible type of the preferential flow in the young, mid‐aged and over‐mature is macroporous flow; it is finger flow or funnel flow in the mature forest soil and will gradually transform to macroporous flow as the soil layer is deeper. The purpose of this research is to analyze systemically the law of soil water movement of dark coniferous forest ecosystem of Gongga Mountain and to provide theoretical basis for the effective watershed management.

Select this Article		Studies on the Sediment Distribution Property of the Guanting Reservoir Watershed for the Last Five Decades Shihai Liu, Ph.D., Zhaoyi Xu, Ph.D., Chunhong Hu, Ph.D., Zhide Xue, and Guoxiong Gao ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)237 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Guanting reservoir (GR) is the second biggest reservoir in the Huabei district, north area of the China, it waters is the upper Yingdinghe river, composed of the sub‐waters of Sangganhe river, Yanghe river and Guishuihe river. The watershed of GR is 43402 square kilometers (sq km), includes the area of Inner Mongolia, Shanxi province, Hebei province and Beijing city. Its storage capacity is 4.16 billion cubic meters, and the flood control volume is 2.99 billion cubic meters. Based on the investigating and monitoring of the sediment distribution in the watershed of GR, its results show that the total sediment yielding due to the soil and water loss in the GR watershed is 4.565 billion tons for the last five decades, among of them, soil and water conservation kept about 0.771 billion tons, it occupies 16.89% of total's amount. The water conservancy project retained about 0.765 billion tons, it occupies 16.76% of total's amount. The irrigation land deposited about 0.965 billion tons, it occupies 21.14% of the total's amount. The water course riverbed deposited about 0.816 billion tons, it occupies 17.88% of total's amount. The GR intercepted about 0.75 billion tons, it occupies 18.02% of total's amount. And the GR discharged about 0.425 billion tons, it occupies 9.31% of total's amount, respectively. According the statistics, to compare the sediment retention ratio of the soil and water conservation of the last twenty years, from 1981 to 2000, and the early thirty years, from 1950–1980, it increased about 26.27%.

back to top

CHINA V

Select this Article		A Critical Issue of Flood Management in China : Flash Flood, Landslide & Mudflow Disasters, Weakness in Defense & Countermeasures Kungang Li ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)238 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The rainfall‐triggered flashflood, landslide and mudflow disasters are regarded as a part of flood disasters in China, and usually called “hilly disasters”. Flood disasters are severe in China, not only cause heavy damages but also bring about many human casualties each year. However, the average human death caused by hilly disasters takes about 2/3 of the total human losses due to floods in recent years, and this has become an evident problem in flood disaster mitigation in the country. After analyzed the flood disasters, the hilly disasters, the present weakness in hilly disaster prevention, the author proposed 6 countermeasures, which are in urgent need to implement recently for reducing human losses caused by hilly disasters.

Select this Article		Debris‐Flow Hazards and Prevention Measures in Beijing Lijun Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)239 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Beijing is located in the north end of north china plain, its coordinates is 115°25′∼117°30′ E and 39°28′∼41°05′N, its total area is 16800 km², in which the mountain area is 10400 km², covers 62% of the total area. The highest mountain is Donglingshan mountain in Mentougou region, its elevation is 2303 m. The slope area of hill below 200m covers 23.1% of the total mountain area. The slope are above 25°covers 46.4% of the total mountain area. The area of the plain is 6400 km², coves 38% of the total area. The lowest elevation is small than 10 m. In history, the Debris‐flow in Beijing mountain area happened frequently, latest years, with the implementation of the control measures, the hazards were prevented effectively.

back to top

CHINA VI

Select this Article		Simulation of Velocity Profile under Ice Cover Jun Wang, Hui Fu, Mingkun Yi, and Xiaoyan Sun ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)240 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Based on a (K‐epsilon) model and using a finite volume, method, a model was developed to simulate the 2‐dimensional velocity profile under ice cover. The comparison of the simulated results from this model with the measured data from experiments indicated that the data matched well with each other. The simulation indicated that the velocity profile varied with the roughness ratio between the ice cover and the river bed. The maximum velocity was larger for unequal roughnesses between the ice cover and the river bed than that for equal roughnesses between the ice cover and the river bed (symmetrical shape for velocity profile). However, the maximum velocity location only shifted within a limited depth range. The trend and value for the velocity profile simulated by this model matched well with those measured in the experiments.

Select this Article		Preliminary Analyses of Effect of Establishing Sluices at the Three Exits of Jingjiang on Scour‐Deposit of the Yangtze and Dongting Lake Gong Ping and Huang Yuling ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)241 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, using one‐dimensional mathematic model of suspended load, joint computation is carried out on the scour‐deposit variations of the mainstream of the middle and lower Yangtze and the regions of the Dongting Lake. On the basis of the achieved results, the effects of establishing and controlling the sluices on the sour‐deposit of the river and lake as well as the three exits' flow dividing and sediment dividing are investigated. The investigated results indicate that after establishing and controlling the sluices, the flow‐dividing and sediment‐dividing amount through the three exits will decrease, of which the Songzikou will have the most decrease; the effect on the scour‐deposit variation of the mainstream's channel will be little; the deposit amount of the Songzikou flow‐dividing channel will increase largely, but that in the regions of the Dongting Lake will decrease obviously.

back to top

CHINA VIII (TAIWAN)

Select this Article		Estimation of Water Resources Availability in Taiwan Nien‐Sheng Hsu and Chih‐Chiang Wei ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)242 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper develops a methodology for estimating water resources availability (that is, the total amount of usable water) under various levels of reliability. Water resources availability in each of the 12 sub‐regions in Taiwan is then calculated by using the developed methodology. The annual water resources availability is finally determined for the four major regions in Taiwan. The results show that the annual water resources availability is 4,423 million m³ in the Northern region, 7,738 million m³ in the Central region, 4,125 million m³ in the Southern region and 3,522 million m³ in the Eastern region. The total annual water resources availability is 19,808 million m³ in Taiwan.

Select this Article		Using System Dynamics to Simulate the Hsinchu Region Development and Water Resources Yen‐Chang Chen, Su‐Pai Kao, and Han‐Chung Yang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)243 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water resource consumption is certainly one of the most complicated and delicate issues in planning and developing an urban area. Supply and demand on a single line is very easy to handle. However, with growing population and expanding city parameters, intertwined water pipes get ever so complicated and subsequently water management becomes an enormous task. Fortunately, with the help of system dynamics analysis, this enormous task can be broken down into easy‐to‐manage and understand steps not only to water managers but also to the general public. Hence, we adopt System Dynamics to build a water consumption model of Hsinchu region to give different strategies of industry and water management, and to illustrate variations of the water supply versus consumption. Based on the structure of Hsinchu water resource system, we used VENSIM to build a system dynamics model, which enables to build a virtual laboratory to test the manager's strategies and to communicate with the interested groups who are not experts of water management.

Select this Article		Assessment of Man‐Made Ponds on Flood Retention and Water Resources Management Ming‐Hsu Li, Ray‐Shyan Wu, and Chuan‐Pin Chien ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)244 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this study is to evaluate the applicability of man‐made ponds on assisting regional water resources management. The domain of interest is the water supply district of the Shihmen Reservoir, especially the water straitened Taoyuan area in northern Taiwan. To overcome the shortage of irrigation water in the past, numerous man‐made ponds were excavated in the Taoyuan area to storage water in wet days. Due to the development of industry and economics in recent years, some farmlands were replaced by buildings and plants and the agricultural purposes of these man‐made ponds have no longer existed. However, flooding and drought are still two natural hazards frequently invading this area. The possibility of given new functions to past man‐made ponds will be explored in this study. Field investigation will be conducted to identify the drainage area, connecting canals, and the associated farmland sizes for selecting target ponds for further analyses. Hydrological analyses will be conducted to evaluate the capability of using man‐made ponds for flood retention. System dynamic simulations will be performed to evaluate the feasibility of man‐made ponds on assisting water resources during drought, as well as the possibility of applying natural purification mechanisms to improve the water quality of man‐made ponds.

back to top

MATHEMATICAL MODELS IN INTERNATIONAL WATER MANAGEMENT

Select this Article		Assessing the Human Water Use Impact in the River Basin Context Yi‐Chen E. Yang and Ximing Cai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)245 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sustainable river basin management is a wide concern currently. However, some quantitative indicators are still needed to make the principle of sustainability more accessible for decision making. One particular question regarding sustainable river basin management is: How much water in a river is needed for sustaining both human activities (including the current ones and projected new developments in the future) and ecosystem integrity? This study assesses water availability with consideration of climatic and hydrologic conditions, water supply infrastructure and water management institutions in the context of river basins. A management model at the river basin scale is applied to assess not only human water demand and supply for domestic, industrial, and agricultural sectors, but also natural demands. Four different indicators: “Criticality Ratio” (CR), “Depletion Ratio” (DR), “Human Impact Ratio” (HR) and “Outflow Ratio” (OR) are used to assess the impact of human interferences on the environment of a river basin. The model and indicators are applied to the major river basins in the U.S., and the result shows that CR is close or greater than 1.0 (withdrawal is more than the renewable water) in the basins of western U.S.; the average value of these indicators will not change significantly during the next 20 years in most of the basins in the U.S.; the variation of CR will become larger in some basins such as California (water region) and Columbia. For the basins with large average CR or large variation, water saving actions should be undertaken; for other basins, there still remains some capacity for additional human uses, but the new development should be assessed very carefully.

Select this Article		Water Resources Management and Modeling in Iraq, The Middle East, and the Nile Basin: Towards Knowledge Transfer and Capacity Building A. M. Salah, R. Al‐Weshah, E. J. Nelson, and M. W. Shammout ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)246 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Mathematical modeling has been assisting water resources engineers for many years. Throughout the last few decades, it has proven to be an indispensable tool to manage water resources in a sustainable context. The objective of this paper is to review some recent modeling and research efforts as knowledge transfer and capacity building in Iraq, Nile Basin countries and the Middle East. The United Nations Education, Science, and Cultural Organization (UNESCO) in collaboration with the Environmental Modeling Research Laboratory (EMRL) of Brigham Young University (BYU) is conducting a knowledge transfer and capacity building for water resources engineers in the Middle East, Iraq and the Nile basin countries. These efforts include training on integrated water resources management and the use of Watershed Modeling System (WMS), developed at EMRL. Ongoing research collaborations include providing scientific and technical guidance to water resources professionals in the aforementioned countries/regions through training workshops, joint research papers and software technical assistance.

Select this Article		Estimation of Non-Point Source Pollution in a Typical River of India Ramakar Jha, V. P. Singh, C. S. P. Ojha, and K. K. S. Bhatia ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)247 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Estimation of non-point source (NPS) pollution from cropland runoff is an important feature of regional water quality planning. In the present work, influx of non-point source pollutant loads in terms of the nitrate (NO₃) and ortho-phosphate (o-PO₄) loads from agricultural areas at different locations of Kali River in western Uttar Pradesh, India, were monitored. Different mathematical techniques, based on mass balance and reaction kinetics, were used to estimate the influx of these loads between different reaches of Kali River. A total of 576 field data sets were obtained from sixteen sampling stations during the period from March 1999 to February 2000 for analysis. Remote sensing IRS-LISS III and PAN digital data were utilized to obtain land use and land cover. A Geographical Information System (GIS) was used to develop a digital elevation model in order to delineate flow paths and agricultural areas contributing non-point pollution to different sampling points. The NPS loads estimated from different existing equations were compared with the corresponding observed values and the suitability of these equations was assessed for Kali River. Certain basin characteristics were critical for assessing the impact of non-point source pollutant loads in the river. The length of the river reach showed the highest correlation with the corresponding non-point source loads.

Select this Article		Optimization of Integrated Water and Wastewater Systems: Case Study of Beirut, Lebanon Patrick A. Ray, Paul H. Kirshen, and Richard M. Vogel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)248 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The water problems of the Middle East and other similarly arid regions are not isolated within any given segment of the water cycle, nor is it efficient to consider the challenges of water supply, demand, disposal and reuse independently. This paper presents an integrated linear, deterministic optimization model developed to determine the minimum cost configuration of future water supply, wastewater disposal, and reuse options for Beirut, Lebanon. To the best of our knowledge, this is the first study to demonstrate an optimization model of the entire anthropogenic water cycle. The model includes interconnections between supply, demand, disposal and reuse, thereby minimizing the cost of both water supply and wastewater disposal simultaneously. By distinguishing between potable and nonpotable demands and permitting the supply of a lower grade of water to some demands, our results reveal new opportunities for cost‐reductions in Beirut's water system. After use of inexpensive conventional sources, reclamation and reuse are shown to be more cost‐effective than desalination to provide nonpotable water for toilet flushing, lawn watering and irrigation. Furthermore, if nonpotable aquifer recharge were permitted, reclaimed water from the centralized wastewater treatment plant could be used to augment Greater Beirut's coastal aquifer, which in turn could supply increased quantities of both potable and nonpotable water to the urban sectors.

back to top

TRANSBOUNDARY MANAGEMENT

Select this Article		Transboundary Issues and Uncertainty in Water Management in Bangladesh ABM Faruquzzaman Bhuiyan, Ph.D. and M. M. Hossain ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)249 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Bangladesh is the lowest riparian country of the Ganges‐Brahmaputra‐Meghna (GBM) basin which constitutes one of the largest river systems in the world. More than ninety percent of the freshwater resources of the country originate outside the political boundary. Currently, Bangladesh faces extreme uncertainty in water management due to increased interventions of the rivers in the upstream reaches in India. Water sharing between the two countries has become a contentious issue since the commencement of the diversion of the Ganges flow at the Farakka Barrage in 1975. Recently disclosed unilateral plan of a mega‐project for inter‐basin transfer of water by India poses greater threat to the entire water resources, ecology and livelihood of several tens of million of poor people. In this paper, the authors analyze the effect of the apparent basin‐wide development on the water resources and pro‐poor water management of Bangladesh. The previous experience of the Ganges set a baseline for that analysis. This shows that the entire Southwestern region of the country has been severely affected including agricultural, ecological and socioeconomic sectors. The adverse effects would multiply extending major part of the country if the proposed transfer of water from Brahmaputra basin is realized. Consequently, Bangladesh is in a dilemma for managing its vital water resources and fragile ecology which has profound implication in medium and long term planning for integrated water resources management. This study examines the sensitivity of the water resources system to the anticipated upstream development. Finally, the shortcomings of the recently approved National Water Management Plan in addressing the potential risk have been scrutinized to indicate probable actions to cope with this crucial issue.

Select this Article		The Berlin Rules on Water Resources: The New Paradigm for International Water Law Joseph W. Dellapenna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)250 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Drawing upon the experience of century, nations have constructed a customary international law for transboundary fresh water resources built around the principle of equitable utilization. The earliest complete formulation of this body of law was the Helsinki Rules on the Uses of International Rivers of the International Law Association of 1966. Like all customary law, this body of international law retains flexibility by being vague while allowing only for relatively primitive enforcement mechanisms. In an effort to improve things, the United Nations drafted a convention to codify the customary law. Even before that the UN Convention enters into force, it has been taken as a cogent summary of the relevant customary international law. The UN Convention, however, fails to integrate the environmental or ecological concerns and relevant human rights that have emerged in international law into the older body of international water law. Beginning in 1996, the International Law Association undertook to reformulate the Helsinki Rules in order to incorporate international environmental law and international human rights law. The project, for which I served as Rapporteur, concluded in August 2004 with the Association's approval of the Berlin Rules on Water Resources. The Berlin Rules speak in terms of a new paradigm of international water law that focuses on ecological integrity, sustainability, public participation, and minimization of environmental harm—principles not reflected in the Helsinki Rules and only developed in rudimentary form and then only for transboundary waters in the UN Convention. This paper will serve to introduce the Berlin Rules.

back to top

WATER AND HEALTH INTERACTIONS

Select this Article		Evaluation of Infrastructure Impacts on Rio Grande/Rio Bravo Water Quality Marcel Dulay, P.E. and David Eaton, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)251 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Staff at the LBJ School of Public Affairs evaluated the impacts of water and wastewater (W/WW) projects along the Texas/Mexico border to determine whether these recently financed projects by the U.S. and Mexican governments achieved two of the Border 2012 goals: reduce water contamination and improve environmental health. The study included: interviews with government officials; compilation of available data and information; and visits to local utilities. The study addressed whether the sources of pollution and other health risks related to water along the Rio Grande/Rio Bravo have been identified, evaluated, and mitigated. It assessed short and long term consequences of W/WW infrastructure in the region. Mexico and the United States have been taking steps to meet the challenge of providing W/WW services to communities along both sides of the border. High growth rates, immigration, and financial conditions in low‐income communities have been barriers to utility service provision. Some of the large Mexican cities along the border offer incomplete utility coverage, have unreliable service during the day, and have inadequate treatment of W/WW. This study has documented how the investment in W/WW has improved human health and the environment, and indirectly facilitated economic prosperity and other social improvements. Wastewater service has been extended in many cities and colonias. Overflow of septic tanks prior to the installation of the wastewater collection system that once endangered children's health has been reduced because of centralized wastewater collection as have problems with sewer runoff during storm events. The WW plants reduced health problems and diseases related to untreated wastewater in the Rio Grande/Rio Bravo and its tributaries. The pipe systems have reduced wastewater leaks into underground water sources. Field observations during the study revealed numerous national commercial stores opening, substantial residential home construction, and a shift from an agricultural to an industrial/commercial economic base. The boost to the economy has generated tax revenue and given utilities a resource base to justify private sector investment. While the projects in the area have moved along with considerable progress, there remains much to be done. Roughly half of the infrastructure projects still need to be completed. Certain colonias still have people hauling water tanks on the back of trucks, which poses a health risk. Some Mexican border cities are now completing what have been emergency and catch‐up projects. Although the W/WW program is addressing the rapid growth with every project completed, a watchful eye must be kept on the region to assure sustainability and avoidance of the root causes that led to the problems in the beginning. The projects evaluated met objectives of increasing access to clean water supply, decreasing reliance on septic tanks, and reducing sewage overflow during storm events.

back to top

BMPS FOR NITROGEN MANAGEMENT

Select this Article		Subsurface Drainage and Its Management in the Upper Midwest Tile Landscapes R. Singh and M. J. Helmers ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)252 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Hydrologic modeling in combination with field measurements is used to understand subsurface drainage patterns and how drainage water management may impact subsurface drainage in the upper Midwest, particularly in Iowa. Long‐term measured subsurface drainage data from an on‐going drainage study in north‐central Iowa was used to calibrate and validate DRAINMOD, a deterministic hydrologic model to simulate a soil‐water regime of surface and subsurface water management systems. The model was then used with long‐term (1945‐2004) weather records with the objective of understanding the timing, duration, and volume of subsurface drainage flow patterns. Controlled drainage, a drainage management practice, was considered in the modeling simulations to assess its potential to reduce subsurface drainage in the upper Midwest. In the north‐central Iowa, approximately 45% of the annual subsurface drainage occurs in the months of April and May, and approximately 80% of the annual subsurface drainage has occurred by the end of June. When simulating controlled drainage practices, there was approximately a 16% reduction in the volume of annual subsurface drainage but most of this reduction was reflected in increased surface runoff. The timing of subsurface drainage in these landscapes specifically during the spring coincides with the time of planting, crop germination, and early crop development. This coincident may limit the effectiveness of drainage management practices such as controlled drainage to reduce subsurface drainage and thereby nitrate‐nitrogen export in the north‐central Iowa.

Select this Article		Combination of Drainage Water Management, Cover Cropping, and Wetland Diversion, as a Suite of BMPs to Reduce Nitrogen Loss from Cropland James L. Fouss and Timothy W. Appelboom ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)253 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Conventional surface and subsurface drainage practices and common crop fertilization methods have resulted in increased nitrate losses from agricultural fields to surface waters. However, research results from several humid region locations over the past 20 years have documented that controlled subsurface drainage can significantly reduce (40–50%) nitrate‐N losses carried in drainage discharge from cropland. Other research has shown the benefit of post‐harvest cover cropping as a nitrogen sink, which also reduces nitrate loss. Research has also shown that nitrate carried in stream flow can be significantly reduced by diverting the stream flow through wetland resource areas before routing it back into the main stream. This paper discusses the combination of these into a suite of BMPs to reduce nitrate losses from cropland for improved stream water quality. Application of this suite of practices throughout the Mississippi River Basin could significantly reduce the amount of nitrate carried to the hypoxic zone in the Northern Gulf of Mexico. A cooperative action group, Drainage Water Management Systems Task Force (ADMS‐TF) was formed in 2002 by employees of USDA's Agricultural Research Service (ARS), Natural Resources Conservation Service (NRCS), Cooperative State Research, Education, and Extension Service (CSREES), and University research and extension partners to promote and implement drainage management (controlled drainage) on cropland to reduce nitrate losses in drainage discharge. The initial efforts of the Task Force, conducted cooperatively with drainage industry representatives, were in eight humid region Midwestern States of IA, IL, IN, OH, MI, MN, MO, & WI. Best management practices (BMPs) of cover cropping and wetland diversion are also recommended as complementary practices to further reduce nitrate load in receiving waters and improve surface water quality. Retrofitting existing subsurface drainage systems for managed (controlled) operation is a major goal of the Task Force. The vast majority of all subsurface drains installed to date in the United States are conventional subsurface drains with gravity flow outlets to the full depth of the drain. An outlet control structure (e.g., overflow weir, valve, or pumped sump) can be used to convert it to a drainage water management system. For new installations, the Task Force has recommended shallower drains, for example no deeper than 3.0 ft., thus reducing the potential for nitrate‐N loss in discharge if an outlet control is not installed. These same principals also apply to deep drainage ditches, and the potential benefits of managing (controlling) ditch drainage systems are also being explored by Task Force members.

Select this Article		Controlled Drainage & Nutrient Management Planning Reduce Drainage Outflow And Nitrogen Transport H. L. Smeltz, R. O. Evans, and D. L. Osmond ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)254 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Controlled drainage, nutrient management planning, and a combination of both were implemented and evaluated throughout the upper Core Creek watershed to reduce nutrient loading to the Neuse River. Hydrology and drainage water quality were monitored at fifteen locations within the watershed for a period of five years. DRAINMOD‐N was calibrated on a field‐by‐field basis to predict long‐term hydrology and nitrate losses based on BMPs implemented and crops grown throughout the watershed. Predicted NO₃‐N reduction was most effectively accomplished when controlled drainage and a nitrogen management plan were used in conjunction with one another. If implemented separately, a nitrogen management plan was predicted to be more effective than controlled drainage alone. The cropping system also impacted the drainage rate and nitrate loss from the fields. Potentially, a 30% and 75% nitrate reduction can be achieved growing cotton or soybeans, respectively, as compared to corn. Controlled drainage reduced the drainage outflow by 6.8 centimeters (21.3%) annually, compared to conventional drainage. This flow reduction accounted for 11.5% of the NO₃‐N reduction leaving the watershed.

Select this Article		Irrigation and Nitrogen Best Management Practices under Drip Irrigated Vegetable Production Michael D. Dukes, Lincoln Zotarelli, Johannes M. S. Scholberg, and Rafael Muñoz‐Carpena ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)255 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Plastic mulch and drip irrigation are commonly used in high intensity vegetable production regions such as Florida. Drip irrigation can be much more efficient than sprinkler irrigation since only the root zone of the cropped area is irrigated. However, improper irrigation management can lead to wasted water and leaching of soluble chemicals such as nitrate. In this project, several irrigation treatments were established that allowed up to five watering events per day depending on a soil water threshold controller (SMS) for tomato and green bell pepper. As a comparison time based treatments (TIME) of once daily irrigation were established to mimic typical producer practices. In addition, zero tension drainage lysimeters were buried 0.6 m below the beds in several treatments to monitor leaching of water and nitrate nitrogen. SMS control of irrigation resulted in 29%–44% less irrigation water used on tomato and 37%–66% less water used on pepper when compared to TIME treatments. Tomato yield was significantly higher on SMS treatments compared to TIME treatments, but yield was similar across all pepper treatments. SMS treatments increased irrigation water use efficiency 2–3 times compared to TIME treatments on both tomato and pepper. Both the amount of water captured in drainage lysimeters and the mass on NO₃‐N were significantly lower on soil water based irrigation control compared to once daily time based irrigation commonly used by producers.

back to top

COMPARISONS OF REFERENCE ET METHODS USED BY AGRICULTURAL WEATHER NETWORK WITH THE ASCE‐EWRI STANDARDIZED PENMAN‐MONTIETH

Select this Article		Use of the ASCE Standardized Reference ET Equation by Agricultural Weather Networks in the Western U.S.: Current Status and Future Challenges P. W. Brown ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)256 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The procedures used by the public agricultural weather networks to estimate reference evapotranspiration (ETref) in the western United States were assessed to determine how many networks have adopted the ASCE Standardized Reference Evapotranspiration Equation ETszEQ. Five states now use the ETszEQ to generate ETref values. Several additional procedures are used to estimate ETref in the region. The most widely used procedures are 1982 Kimberly Penman Equation and the Nebraska Penman Equation. ETref values computed using these two Penman Equations were found to be similar to ETref values computed using the ETszEQ, suggesting a switch to the ETszEQ would not cause serious problems with existing irrigation management/crop water use programs in states using these two Penman Equations.

back to top

FAMILIES OF CROP COEFFICIENTS: THEIR BASIS, QUALITY, AND TRANSFER ABILITY

Select this Article		Development of Bahiagrass Crop Coefficients Using Weighing Lysimeters and Eddy Correlation Methods X. Jia, M. D. Dukes, and J. M. Jacobs ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)257 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Bahiagrass (Paspalum notatum) crop coefficients (K_c) were determined in central Florida in 2004 and 2005. Crop evapotranspiration (ET_c) rates were measured simultaneously using weighing lysimeters and an eddy correlation system. Reference evapotranspiration (ET_o) values were calculated by the standardized ET_o equation by the Environmental and Water Resources Institute of American Society of Civil Engineering using weather data from a nearby reference ET station. The K_c values were developed from the measured ET_c and calculated ET_o values. Relevant soil moisture results indicated that the soil at the experimental sites was not water stressed and had a full canopy cover. A 12 cm grass height was closely maintained during the two year study period. Lysimeters were considered as the standard to directly measure ET_c. In this research, three relative large weighing lysimeters, each equipped with four commercial load cells, provided an accuracy of 0.29 mm. The lysimeters were double steel tanks with an inner surface area of 2.32 m² and a soil depth of 1.37 m. An eddy correlation system was used to directly measure the turbulent fluxes of water vapor (LE) and sensible heat (H) above the crop canopy. The distance between the lysimeters and the eddy stations was 80 m. Daily crop coefficient values were estimated using ET_c measured by the lysimeters and the eddy correlation system. The K_c values determined by the eddy correlation method were similar to that by the lysimeters during the summer season. The largest K_c difference was found in winter time when the grass growth was minimal and irrigation requirement was negligible.

Select this Article		Converting K_c Values between ET_o and ET_r Atef Ghandour, Richard L. Snyder, Kent Frame, Simon Eching, Bekele Temesgen, and Baryohay Davidoff ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)258 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The ASCE‐EWRI recently published a report on the estimation of reference evapotranspiration for short canopies (ET_o) and tall canopies (ET_r) using a modified Penman‐Monteith equation. Currently, another EWRI committee is developing crop coefficient (K_c) values to estimate crop evapotranspiration by multiplying by either ET_o or ET_r. Most crop coefficients were developed using either ET_o or ET_r, and, because the relationship between ET_o and ET_r varies with microclimate, it is difficult to convert crop coefficients from one reference surface to the other. In this paper, a simple method to convert between ET_o and ET_r and between the corresponding Kco and Kcr factors is discussed.

Select this Article		Evaluation of FAO‐56 Alfalfa Crop Coefficients in an Arid Southwestern U.S. Climate Aaron M. Beutler and Andrew A. Keller ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)259 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The ASCE‐EWRI standardized Penman‐Monteith equation was used in conjunction with a soil water balance model to estimate crop ET for five years in an irrigation scheduling program for a 28,000‐hectare farm in northern New Mexico. The calculated crop ET was then compared to measured crop ET to evaluate the FAO‐56 tabulated alfalfa crop coefficients. Calculated ET_c estimates exceeded measured ET_c determined by water balance by 23% in the first 80 days, resulting in a 7.5 cm cumulative difference between calculated and measured ET. Possible causes for this disparity were examined and corrected. Errors in the near surface neutron probe measurements were found and corrected, local crop growth stages were applied to the data, weather data were evaluated and corrected, code was added to eliminate possible aridity, a user defined wind limit was added, application efficiency was derived and applied, and the FAO‐56 suggested climatic correction was added. The combination of corrections did not completely reduce the cumulative difference. The tabulated FAO‐56 Kcb coefficients were adjusted to further reduce the cumulative difference. With all positive corrections, the cumulative ASM difference was reduced from 7.5 cm to ∼1 cm.

Select this Article		Crop Coefficients Developed at Bushland, Texas for Corn, Wheat, Sorghum, Soybean, Cotton, and Alfalfa T. A. Howell, S. R. Evett, J. A. Tolk, K. S. Copeland, D. A. Dusek, and P. D. Colaizzi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)260 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Crop coefficients from evapotranspiration measured with large, precise weighing lysimeters since 1988 at Bushland, TX for major regional irrigated crops — corn, wheat, sorghum, soybean, cotton, and alfalfa — are presented. The ASCE/EWRI standardized reference evapotranspiration equation for daily weather data for short (grass) and tall (alfalfa) was used as the base. Crop coefficients for both ET_os and ET_rs were summarized. They were typically in agreement with K_cb values from Davis, CA; Kimberly, ID; and from FAO‐56.

back to top

IMPROVED DISTRICT MANAGEMENT UNDER INCREASED COMPETITION FOR SCARCE WATER SUPPLIES

Select this Article		Water Banking as a Method to Improve Water Management in Utah's Sevier River Basin Wynn R. Walker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)261 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Sevier River Basin in central Utah is one of the state's most critically water‐short areas. For nearly a century the users of the Sevier River have relied on multiple water‐banking mechanisms to improve their water management practices. Three of the most important water banking mechanisms are carry‐over storage credits, temporary storage of direct flow rights, and intra‐basin exchanges. This paper demonstrates the impact these three mechanisms have had historically in the Sevier Basin. Carry‐over storage accounts for about 30% of annual water deliveries. Direct flow right storage improves these small rights by about 20% in one case and 5% in another. The intra‐basin exchanges account for about 17% for one right. Water banking is a viable option for further water management improvements in the Sevier River Basin but the legal and institutional constraints will be difficult to overcome.

Select this Article		Hydraulic Model of the Belle Fourche Irrigation District Using EPA SWMM 5.0 Curtis Schoenfelder, Scott Kenner, and Dan Hoyer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)262 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A hydraulic model of the Belle Fourche Irrigation District (BFID) South Canal was developed using Environmental Protection Agency Storm Water Management Model Version 5.0 (EPA SWMM 5.0). Stage, flow, and structure setting data were collected throughout the BFID during the 2005 irrigation season (June–September) for model calibration. The model is able to simulate many possible combinations of flows, stages, and structure settings and will assist the BFID personnel in making adjustments to the system. The model will help improve operational efficiency and reduce the total suspended solids (TSS) in the Belle Fourche River system.

Select this Article		SRP Irrigation System Modeling Robert S. Gooch, P.E. and Dennis O. Siewert, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)263 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Salt River Project (SRP) is an irrigation water users association that serves approximately 250,000 acres (100,000 hectares) in south central Arizona in the vicinity of the City of Phoenix. When SRP was first developed over a hundred years ago, the service area was nearly entirely farmland or desert. Now it is approximately 85% urban, which has greatly changed how SRP operates and maintains its facilities. To assist in planning for continued changes in operational, maintenance and regulatory requirements, SRP has developed a series of models that are able to forecast land use and water demand, determine where in the system demand will be changing, and determine what water quality effects of well water and different mixes of surface water will be. Several studies have used these models including an available capacity study, well operation and water quality study, well effectiveness study, WTP siting study, and a dilution study for a Generating Station. This paper describes these models and some of the studies that have used them.

Select this Article		Water Balance for a Predominantly Surface Irrigated District in Southern Idaho David L. Bjorneberg, Nathan O. Nelson, and Dale T. Westermann ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)264 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water quantity and quality are being measured in an 82,000 ha irrigation district in southern Idaho to determine the effects of conservation practices, primarily conversion from furrow to sprinkler irrigation, for the Conservation Effects Assessment Project (CEAP). The percentage of sprinkler irrigated land has steadily increased from about 10% in 1990 to more than 30% in 2005. The objective of this study was to calculate a preliminary water and soluble salt balance for April through November, 2005. The water balance was calculated by subtracting measured outflow and estimated crop water use from measured inflow and precipitation. Precipitation was about 250% of normal in April and May, which delayed irrigation for many crops and probably increased the amount of return flow during these months. Water diverted for irrigation was 82% of the total water input to the irrigation district (inflow plus precipitation). Precipitation contributed 16% of the total input. Thirty‐six percent of the diverted water left the irrigation district as surface return flow from April through November. This percentage will increase on an annual basis because return flow continues through the winter months after irrigation diversions have ceased. The irrigation district was a source of suspended sediment and a sink for soluble salts. April through November 2005 monitoring showed a net gain of 1620 kg ha⁻¹ of soluble salts in the irrigation district, which could be a long‐term concern if these salts accumulate in the root zone. Net sediment loss was 102 kg ha⁻¹, which is less than the 461 kg ha⁻¹ measured during a similar study in 1971. These preliminary results indicate that converting to sprinkler irrigation, along with other conservation practices, has reduced sediment loss from this irrigation district. However, solid conclusions cannot be made until at least one year of monitoring is complete to adequately characterize annual trends, particularly the quantity and quality of non‐irrigation season return flows.

back to top

INTERNATIONAL IRRIGATION AND DRAINAGE

Select this Article		Continuing Education Programs for Irrigation Engineers in Developing Countries: A Pressing Need L. Humberto Yap‐Salinas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)265 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The field of irrigation, both as an area of work and as an area in which to seek a degree, has undergone great changes in the U.S. Great advances have taken place in the technology of irrigation, enabling greater crop production with greater efficiency of water use. However, at the same time, farming in the U.S. has become increasingly the domain of large agribusinesses, and fewer young Americans are seeking careers in agriculture and irrigation. Universities have experienced decreasing enrollment in their irrigation and drainage programs. Overseas, particularly in developing countries, the situation is quite different. For many developing countries, irrigation has been a key factor in their development and is becoming even more crucial as globalization, with its need for rapid response to market demands, has taken place. Irrigation engineers are very much needed in developing countries, and they need to be up‐to‐date on the latest and most feasible technological tools. However, few irrigation engineers in these countries have either the opportunity or the means after they graduate for continuing their education through conferences and seminars, and journals. Thus while young graduates are aware of innovations, more mature engineers, who are further along in their careers and often occupying important positions in ministries of water or agriculture, are often not. This situation has a variety of consequences not only for the agricultural sectors of developing countries, but also for the overall development of those countries, due to the economic importance of irrigation,. This paper explores these consequences and discusses ways to provide continuing education opportunities for irrigation engineers in developing countries.

Select this Article		Essential Dimensions and Elements in the Design of Irrigation System Management Transfer Projects L. Humberto Yap‐Salinas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)266 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Irrigation projects have been done in developing countries for many years and for many purposes. In the last thirty years, much emphasis has been placed in these projects upon transferring management of irrigation systems to the water users. The transfer process is often not an easy one, and over time it has become apparent that various elements, working in layered dimensions, need to be present in order to achieve sustainable results and the induction of development in rural societies. These elements and dimensions need to be identified and focused upon at the inception of design of a project; the absence of one or more of these as the project develops can cripple or derail the desired outcome.

Select this Article		Concerned Aspects in Large Drainage Project: A Case Study of the Mun River Bypass Project in Thailand N. Sangtian, K. Sriworramas, S. Jaensirisak, and S. Bhokha ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)267 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Flooding from Mun river in Ubon Ratchathani has periodically occurred as the province locates in one of the largest water basins in Thailand. In 2002, a destructive flooding with a flood period of 73 days occurred in Ubon Ratchathani in which agricultural division and business were strongly affected. Feasibility of Mun river bypass project was studied to accelerate flow rate during the flooding period. The present paper shows historical review of several bypass channel projects in Thailand and intensively presents systematical study on critical concerned aspects, including hydraulic engineering, irrigation system, groundwater and economic of the Moon River Bypass project with an estimated cost of 110 million US dollars.

back to top

IRRIGATION AND DRAINAGE (POSTERS)

Select this Article		An Expansion of the Ungaged Pan Evaporation Using Neural Networks Model in Rural Regions, South Korea Sungwon Kim, Ph.D., P.E. and Hongkee Jee, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)268 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The generalized regression neural networks model (GRNNM) embedded genetic algorithm(GA) is developed and applied to expand the ungaged or the missing pan evaporation (PE) in rural regions of the north Gyeongsangbuk‐do such as Yeongju, Bongwha, and Andong stations respectively, South Korea. The Songriwon dam with small‐sized reservoir, which is located near to Yeongju and Bongwha station, will be constructed for flood control and water supply and it will damage many kinds of specific and traditional crops such as Korean ginseng, the red pine mushrooms and honey‐sweet apples and so on. Therefore, reliable evaporation data will be necessary to prevent crops damages and control water transfer as well as to reduce the drought mitigation. The developing processes of the GRNNM‐GA consist of the three major parts such as the training, the testing, and the reproduction performance respectively. From this study, the reliable expansion system of PE is constructed and suggested the basic data for irrigation and drainage networks in rural regions, the north Gyeongsangbuk‐do of South Korea.

Select this Article		Estimation of the Reference Evapotranspiration Using Neural Networks Model and Limited Climatic Variables Sungwon Kim, Ph.D., P.E. and Hung‐Soo Kim, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)269 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The generalized regression neural networks model (GRNNM) embedded genetic algorithm (GA) is developed and applied to estimate the alfalfa reference evapotranspiration (ET_r) in rural regions of the north Gyeongsangbuk‐do such as Yeongju, Bongwha, and Andong station respectively, South Korea. Since the observed data of ET_r using the lysimeters have not existed in this region, the reliable data of ET_r will be necessary to prevent crops damages as well as reduce the drought disaster mitigation. The developing processes of the GRNNM‐GA consist of the two major parts such as the training and the validation performance respectively. From this study, the reliable data of ET_r is constructed and suggested the reference data for irrigation and drainage networks system. It is possible to construct the reference evapotranspiration estimation system (RETES) in rural regions, the north Gyeongsangbuk‐do of South Korea.

Select this Article		Climatic Risk to Cotton Production in the Ogallala Aquifer Region A. Esparza, P. H. Gowda, R. L. Baumhardt, and C. A. Robinson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)270 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Renewed interest in cotton (Gossypium hirsutum L.) production in the Ogallala aquifer region can be tied to increased profitability associated with the growing demand for cotton, development of short‐season varieties, rising energy costs, and declining water levels in the Ogallala Aquifer. However, the feasibility of growing cotton considering climatic characteristics of the region has not been determined. In this study, we used a county‐wise daily maximum and minimum air temperature database to assess climatic suitability for farming cotton in the Ogallala aquifer region. For this purpose, a 30‐year (1971–2000) climatic dataset was obtained from the National Climatic Data Center. Exceedance probability curves for total heat units accumulated during growing season were developed and used to identify those counties that are suitable for farming cotton at different exceedance probability levels. Results indicate that counties in the southern high plains region provide suitable climatic conditions to grow cotton as expected. However, counties in the central high plains that include the Texas and Oklahoma panhandles and southern Kansas require varieties adopted for cooler and shorter growing seasons. Out of 131 counties, 102 counties receive 1800 or more heat units during the planting season at least once every two years. Significant water savings is possible if producers were to switch 50 percent of their corn acreage to cotton. Furthermore, information derived from this study is of interest to producers and commodity groups, seed developers, crop insurance companies and water resource management agencies.

back to top

IRRIGATION WATER MANAGEMENT

Select this Article		Estimate Irrigation Water Use by Data Assimilation Dingbao Wang and Ximing Cai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)271 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water use is usually metered in municipal and industrial sectors but not in agriculture. The survey data of irrigation water use are highly variable in quality, depending on reporting requirements at the level of the state, the watershed, or the irrigation project. In hydrologic‐agronomic models, irrigation is either treated as an estimated fixed input or determined by the model through certain prescribed empirical criteria. This paper presents an approach for estimating irrigation water use based on a hydro‐agronomic model (Soil Water Atmosphere Plant model — SWAP) and crop evapotranspiration (ET) assessed from remote sensing utilizing the data surface energy balance algorithm for land. A coupled forward‐inverse procedure is implemented for the analysis. The forward procedure is to assimilate the ET estimation into the hydro‐agronomic model through the ensemble Kalman filter, which is an efficient data assimilation method for complex nonlinear dynamic models. The inverse procedure is to search irrigation scheduling using a genetic algorithm (GA). The two procedures are tightly coupled through the objective function, which is based on the likelihood function assessed from the data assimilation framework by maximizing the joint distribution of all “observed” crop ET. The forward‐inverse framework incorporates model errors and observation errors, which allows the assessment of the inaccuracy of the irrigation estimate. The soil hydraulic properties of the case study area, which are the most sensitive parameters of the SWAP model, are estimated by genetic algorithm based on the available soil survey data and the in‐site soil moisture measurement in a grass land.

Select this Article		Why Use Reference Evapotranspiration to Calibrate Satellite‐Based Energy Balances? Richard G. Allen, Masahiro Tasumi, and Ricardo Trezza ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)272 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Satellite‐based surface energy balance has become a very useful tool for determining actual evapotranspiration (ET) over large areas. Major uncertainties in derived ET exist, however, due to error and bias introduced to the surface energy balance and ET by components of the energy balance. These biases include biases in atmospheric correction, albedo calculation, net radiation calculation, thermal band and surface temperature, air temperature gradient used in sensible heat flux calculation, soil heat flux function, and extrapolation to 24‐hour and longer periods. At the University of Idaho, we use calculated hourly reference evapotranspiration (ET_r) to calibrate the surface energy balance during processing to remove a majority of these biases. The ET_r method uses alfalfa reference ET calculated with the ASCE‐EWRI standardized Penman‐Monteith equation. Experience and field verification with this method has created confidence in using ET_r for image calibration rather than using available energy only. In addition to its use to calibrate the energy balance, ET_r is used to extrapolate ET images to 24‐hour and longer periods. The use of ET_r provides equivalency and congraency with ET as estimated using the traditional crop coefficient × ET_r approach. With Landsat images, full‐cover alfalfa or other high leaf area vegetation can be identified, and ET from these fields is expected to be near the value of alfalfa ET_r. Comparisons between ET by METRIC, ET by lysimeter and ET by traditional methods suggest that METRIC or similar methods hold promise as efficient, accurate, and inexpensive procedures to predict actual evaporation fluxes throughout a growing season.

Select this Article		Yield Response of Corn to Timing of a Limited Seasonal Irrigation Depth (150 mm) with Subsurface Drip Irrigation José O. Payero, David Tarkalson, and Suat Irmak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)273 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Deficient water supplies in many areas of the High Plains of the USA are forcing many farmers to produce corn (Zea mays L.) under deficit irrigation conditions. When water is limited, it is especially important to know.how to time irrigations to optimize yield and water use efficiency. The objective of this study was to evaluate the effect of application timing of a fixed and deficient seasonal irrigation depth (150 mm) on grain yield, yield components, and water use characteristics of corn irrigated with subsurface drip irrigation in a semiarid climate. The study was conducted during 2005 at the University of Nebraska‐Lincoln West Central Research and Extension Center at North Platte, NE. Eight irrigation treatments (T1–T8) were evaluated, which consisted of dividing the application of 150 mm of water in different proportions during the months of July, August, and September. Irrigation timing resulted in significant differences in yield and actual seasonal evapotranspiration (ET_d). Yields were positively and linearly correlated to seasonal ET_d and to the ratio of ET_d and crop evapotranspiration with no water stress (ET_w). Although all treatments received the same seasonal irrigation depth, seasonal differences in ET_d among treatments were as much as 70 mm (2.8 in), which resulted in yield differences of approximately 2 Mg ha⁻¹ (32 bu Ac⁻¹). Irrigation timing also affected grain test weight and grain moisture. The treatments that received all of the irrigation water in July and August resulted in the highest seasonal ET_d, ET_d/ET_w, and grain yield. The opposite occurred with the treatment that received most of the irrigation water in September. These results point out the importance of proper irrigation scheduling to assure that irrigation is applied at the time needed to prevent crop stress, especially at the times of high ET_d rates when stress can reduce seasonal ET_d the most and consequently has a greater effect on yield.

Select this Article		Corn Yield Response to Different Irrigation Depths with Subsurface Drip Irrigation José O. Payero, David Tarkalson, and Suat Irmak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)274 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Quantifying the yield response of crops to water inputs is important for establishing adequate irrigation scheduling strategies. The objective of this study was to evaluate how different seasonal irrigation depths applied to corn (Zea mays L.) affected the soil water balance, corn water use, corn yield, and yield components in a semiarid climate. The study was conducted during 2005 at the University of Nebraska‐Lincoln West Central Research and Extension Center at North Platte, NE. Six irrigation treatments were evaluated, which received incremental seasonal irrigation depths ranging from 53 to 254 mm using a subsurface drip irrigation system. For each treatment, a water balance approach was used to estimate several water variables, including daily and seasonal actual crop evapotranspiration (ET_d), crop evapotranspiration when water is not limited (ET_w), evaporation (E), transpiration (T), and deep percolation. All treatments were deficit‐irrigated, and total water (soil water + rain + irrigation) was enough to produce seasonal ET_d values between 81 and 98% of seasonal ET_w. Seasonal irrigation affected ET_d, especially its T component. Although E was a significant portion of ET_d, it was mostly due to rainfall and was not affected by irrigation. Grain yield was linearly related to seasonal irrigation (yield = 0.0123x + 9.52, r² = 0.94), total water (yield = 0.0123x + 3.01, r² = 0.94), ET_d (yield = 0.0212x − 1.77, r² = 0.85) and ET_d/ET_w (yield = 14.08x−;1.37, r² = 0.89). Seasonal irrigation also affected grain moisture, grain test weight, stover moisture, and the dry weights of the stover, grain, and cob. The percent of the above‐ground plant dry weight represented by each component (grain, stover, and cob) was practically constant among irrigation treatments. On average for all treatments, the grain, stover, and cob accounted for 57.9 (= harvest index), 33.5 and 8.6 % of the above‐ground plant dry weight, respectively.

back to top

MANAGEMENT OF SURFACE IRRIGATION SYSTEMS

Select this Article		The NRCS Intake Families for Furrow Irrigation — Old and New Wynn R. Walker and Sinisha Ivans ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)275 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In the 1950's various personnel of the Soil Conservation Service (SCS) of the USDA began a concerted effort to develop general intake relationships to support surface irrigation assessments when field measurements were not available. More than 1600 Ring infiltrometer tests were made primarily in alfalfa fields of Colorado, Wyoming, North Dakota, South Dakota, and Nebraska. In 1959, J. T. Phelan proposed the intake families now found in the USDA‐SCS National Engineering Handbook, Section 15, Chapters 4 — Border Irrigation and 5—Furrow Irrigation. These intake families were revised in 2004 to make them more compatible with field data that have evolved since the original publication. This paper summarizes the history of the original development and the rationale for the later revisions. A comparison between original and revised intake families for furrow irrigation is presented along with detailed correspondence tables. English units are used herein to coincide with the original work.

Select this Article		On‐Farm Studies of Water Use and Water Quality for Rice Production E. D. Vories, P. L. Tacker, I. Chaubey, R. Lipsey, W. Smith, and B. K. Schaffer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)276 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract One of the major rice producing areas of the US, the L'Anguille River watershed in eastern Arkansas, has been experiencing declining groundwater levels and has been designated for a total maximum daily load (TMDL) limit for total suspended solids. Previous on‐farm water‐use studies in Arkansas conducted during the 1999 through 2002 growing seasons compared traditional flooded rice production to an alternative method known as multiple‐inlet rice irrigation. Those studies showed that the multiple‐inlet system required an average of 24% less irrigation water than conventional flooding without yield loss. A shortcoming of the studies, however, was that they did not address any effects on quantity or quality of the runoff water. A multidisciplinary project was started in 2003 to investigate the impact of multiple‐inlet irrigation on water use, runoff volume, and quality of the runoff water within the L'Anguille River watershed. In 2004, two paired rice fields within the watershed were equipped to allow computation of a complete water balance throughout the flood period, with sampling of inflow and runoff water. In 2005, the project expanded to three paired fields. Based on a field in St. Francis County, Arkansas, the relative difference between inflows for two production systems (conventionally flooded and multiple inlet) appeared consistent throughout the season. Based on three pairs of fields located within 25 km of each other, water quality entering and leaving the field did not differ for samples collected on 5 August, 2005. The concentration of total nitrogen was significantly lower for the multiple inlet system. However, the limited data included in this report should not be used to make broad inferences about water use or water quality associated with rice production.

Select this Article		An Integrated Software Package for Simulation, Design, and Evaluation of Surface Irrigation Systems Eduardo Bautista, James Schlegel, Theodor S. Strelkoff, Albert J. Clemmens, and Robert J. Strand ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)277 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The USDA Agricultural Research Service is developing WinSRFR, a new surface irrigation software package. WinSRFR integrates the functionality of existing software, namely SRFR, BORDER, and BASIN, and provides the foundation for future software developments. This paper discusses the WinSRFR project objectives, program functionality and components, key software architectural features, and future developments. Release of the initial version is scheduled for 2006.

Select this Article		Extreme Drought and Water Supply Management in California Julien Harou, Josue Medellin, Tingju Zhu, Stacy Tanaka, Jay Lund, Scott Stine, Marion Jenkins, and Marcelo Olivares ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)278 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The geological record contains extreme droughts beyond those seen in historical hydrologic records. For California, the geological record contains several extreme droughts the last few thousand years. Two of these droughts are 120–200 years long, with mean annual streamflows between 40% and 60% of the historical mean. This study synthesized a 72‐year historical record for a drought of this character, having a mean flow of 40% of the historical record. This hydrologic time series was used as input to an economic‐engineering optimization model of California's water supply system (CALVIN). The model allows exploration of how California's water management system might respond to such an extreme drought and provides preliminary estimates of economic costs and effects of such a drought on water operations and demands. The overall results show the importance of management flexibility and adaptation in response to extreme stresses on water systems. Results also illustrate the physical ability of extensive, diversified, and highly intertied water systems with heterogeneous water demands to economically respond to such extreme stresses. The study provides a different approach to climate change studies, focusing on observed past changes in climate from the geologic record rather than downscaled general circulation model results to provide hydrologic scenarios.

back to top

MANAGEMENT OF TMDLS IN THE SAN JOAQUIN VALLEY, CA

Select this Article		The San Joaquin Valley Westside Perspective Nigel W. T. Quinn, M. ASCE, J. Christopher Linneman, M. ASCE, and Kenneth K. Tanji, Lif. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)279 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Salt management has been a challenge to westside farmers since the rapid expansion of irrigated agriculture in the 1900's. The soils in this area are naturally salt‐affected having formed from marine sedimentary rocks rich in sea salts rendering the shallow groundwater, and drainage return flows discharging into the lower reaches of the San Joaquin River, saline. Salinity problems are affected by the imported water supply from Delta where the Sacramento and San Joaquin Rivers combine. Water quality objectives on salinity and boron have been in place for decades to protect beneficial uses of the river. However it was the selenium‐induced avian toxicity that occurred in the evaporation ponds of Kesterson Reservoir (the terminal reservoir of a planned but not completed San Joaquin Basin Master Drain) that changed public attitudes about agricultural drainage and initiated a steady stream of environmental legislation directed at reducing non‐point source pollution of the River. Annual and monthly selenium load restrictions and salinity and boron Total Maximum Daily Loads (TMDLs) are the most recent of these policy initiatives. Failure by both State and Federal water agencies to construct a Master Drain facility serving mostly west‐side irrigated agriculture has constrained these agencies to consider only In‐Valley solutions to ongoing drainage problems. For the Westlands subarea, which has no surface irrigation drainage outlet to the San Joaquin River, innovative drainage reuse systems such as the Integrated Farm Drainage Management (IFDM) offer short‐ to medium‐term solutions while more permanent remedies to salt disposal are being investigated. Real‐time salinity management, which requires improved coordination of east‐side reservoir releases and west‐side drainage, offers some relief to Grasslands Basin farmers and wetland managers — allowing greater salinity loading to the River than under a strict TMDL. However, current regulation drives a policy that results in a moratorium on all drainage return flows to the San Joaquin River as will be explained in this paper. Seasonal wetlands have little choice but to drain in order to sustain waterfowl habitat. This paper summarizes the short and long term strategies available to westside agricultural and wetland entities and reviews implications of success and failure.

Select this Article		The Need and Development of TMDLs for the San Joaquin Valley of California Leslie F. Grober, Joe Karkoski, and William R. Johnston, F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)280 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water quality impairments in the San Joaquin River (SJR) have occurred as a result of large‐scale water development projects coupled with discharges from agricultural and municipal sources. Consequently, the SJR is listed as impaired on the Clean Water Act (CWA) 303 (d) list of impaired waters for a number of pollutants including salt and boron, the organophosphorous pesticides diazinon and chlorpyrifos, and oxygen demanding substances. The CWA requires that a Total Maximum Daily Load (TMDL) must be developed for waters on this impaired waters list. TMDLs are required to be established at the level necessary to implement applicable water quality standards. The TMDLs establish the pollutant assimilative capacity of a waterbody, and then allocate maximum allowable loading of that pollutant to its various sources. The Central Valley Regional Water Quality Control Board (Central Valley Water Board) has the responsibility and authority to develop TMDLs for these and other listings in the SJR and other water bodies in California's Central Valley. It is anticipated that the SJR TMDLs adopted by the Central Valley Water Board will be implemented using a mix of regulatory tools including prohibitions of discharge, establishment of fixed load limits in waste discharge requirements, and waivers of waste discharge requirements if certain other conditions are met. It is the flexibility provided through waivers of waste discharge requirements and load limits tied to real time water quality conditions that has encouraged watershed and stakeholder groups to develop plans for achieving water quality objectives. These plans include the use of tools beyond the purview of the Central Valley Water Board to regulate. Establishment of the regulatory backstop provided by the TMDLs provides the regulatory incentive for watershed and stakeholder groups to follow through with the adaptive implementation needed to address the diverse water quality impairments. In the absence of such adaptive implementation, attainment of standards will be achieved through enforcement of: (1) prohibitions of discharge, and (2) fixed load limits in waste discharge requirements that are developed for agricultural and municipal discharges. This paper will describe the technical and regulatory elements of the Central Valley Water Board's TMDLs for salt and boron, diazinon and chlorpyrifos, and oxygen demanding substances.

Select this Article		The San Joaquin Valley East Side Perspective Walter P. Ward, William R. Johnston, F. ASCE, and Michael Niemi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)281 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The East Side sub‐watershed of the San Joaquin River Basin includes the area of five /irrigation districts, the Merced ID, the Turlock ID, the Modesto ID, the Oakdale ID and the South San Joaquin ID. These districts plus adjacent land irrigated with ground water cover approximately 240,000 ha (600,000 acres) of the east side of the San Joaquin Valley between the San Joaquin River on the south and the Stanislaus river on the north. The five irrigation districts hold the majority of the water rights to the flow of the Merced, Tuolumne and Stanislaus Rivers that provide excellent quality snowmelt water from the Sierra Mountains. Most of the snowmelt runoff generally occurs between April and July each year. Consequently, the districts have large storage reservoirs to capture the runoff for power generation and irrigation during the remainder of the year. Each river has required instream flows below the major reservoirs during some or all months of the year. The release of water from the reservoirs and from irrigation district canals currently dilutes the more saline water in the San Joaquin River that originates from the west side of the San Joaquin Basin during most of the year and particularly during the irrigation season regardless of the volume of flow. The Central Valley Regional Water Quality Control Board's (Regional Board) Salt and Boron Total Maximum Daily Load (TMDL) could in certain instances, require a reduction in the discharge of East Side water with salinity levels between 315 and 700 uS/cm (0.315 and 0.7 dS/m), during various times of some years. At the same time, discharges of water with higher salt concentrations and corresponding higher salt loads would be allowed from the West Side of the Valley. The elimination of the discharge of this “good quality” water to the San Joaquin River could require the release of additional water from New Melones Reservoir on the Stanislaus River in order to dilute the West Side discharges and meet the water quality objectives at Vernalis. This paper discusses the East Side perspective on the fixed load limits in the load based salinity and boron TMDL and the Dissolved Oxygen TMDL for the San Joaquin River.

Select this Article		A Water Quality Improvement Approach for the San Joaquin River Basin Lowell F. Ploss and Byron M. Buck ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)282 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Lower San Joaquin River in the San Joaquin Valley of California is listed on the Federal Clean Water Act (CWA) 303 (d) list as impaired for elevated levels of salinity and boron. Additionally, the Lower San Joaquin River (LSJR) and southern portion of the Sacramento‐San Joaquin Delta is listed for low levels of dissolved oxygen. These listings are but two of many recognized water management problems on the San Joaquin River, two of which where regulatory action was being actively pursued. It was recognized by many interested parties along the River that traditional TMDL type, load‐based solution being pursued by regulatory authorities would be practically limited and potentially counterproductive. Therefore water interests having a stake the method of solution, set about to develop an alternative implementation plan that would integrate multiple solutions to achieve the water quality objectives. Over an 18‐month period the San Joaquin River Water Quality Management Group (Group) identified and evaluated potential actions and scenarios to address constituents and mechanisms contributing to the salinity, boron and dissolved oxygen levels. The outcome of the Group deliberations is a suite of tools/actions to modify flow, address the physical changes and reduce or manage loads, which once implemented, in an integrated manner will improve water quality of the river. The actions will assure the achievement of water quality standards for salinity and significantly improve performance toward achievement of standards for dissolved oxygen. The process of developing the recommendations and the analysis of their expected results will be described in this paper.

back to top

MANAGEMENT/EVALUATION OF IRRIGATION SYSTEMS

Select this Article		Field Performance Analysis of Center Pivot Sprinkler Packages Dan Spare, P.E., Aaron Beutler, and Ron Bliesner, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)283 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract During the cropping years of 2002 and 2003, the sprinkler performance of 304 center pivot irrigation systems on the Navajo Indian Irrigation Project located near Farmington, New Mexico was evaluated. System discharge was measured and can catch tests completed on each system. Six types of sprinklers were evaluated including flat overhead spray, low angle impact sprinklers, Nelson spinners, Senninger I‐Wob's, and three types of spray heads on drops. The large number of tests completed under field conditions allows statistical analysis of the results to determine repeatability and appropriateness of the test method on the various types of sprinklers tested. This paper presents the range of results for each sprinkler type as well as an assessment of the reliability of the results. The strengths and weaknesses of the testing programs are discussed and recommendations presented for the use and interpretation of the data.

Select this Article		Concepts of In‐Canopy and Near‐Canopy Sprinkler Irrigation Freddie R. Lamm, Terry A. Howell, and James P. Bordovsky ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)284 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The use of in‐canopy and near‐canopy sprinkler application from mechanical move systems is prevalent in the U. S. Great Plains. These systems can reduce evaporative by nearly 15%, but introduce a much greater potential for irrigation non‐uniformity. Close attention to the design, installation and operational guidelines for these systems can prevent many non‐uniformity problems from becoming unmanageable.

Select this Article		An Artificial Dry Reference Surface for Predicting Canopy Temperature Dynamics from a Moving Irrigation System R. Troy Peters and Steven R. Evett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)285 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Elevated crop canopy temperatures are a useful indicator of water stress. Single‐time‐of‐day canopy temperatures of large field areas can be detected by infrared thermometers (IRTs) mounted on center pivots or lateral move irrigation systems. Determining canopy temperatures at other times of day from these measurements requires a method of estimating diurnal canopy temperature dynamics due to changing environmental conditions from a one time‐of‐day measurement. This has been shown to be possible by using canopy temperature dynamics measured with an CRT in a stationary reference location in another part of the field to scale the one time‐of‐day measurement. It has also been shown that the water stress condition of the reference location has little effect on the errors of the predicted canopy temperatures. It would simplify instrumentation and programming if the reference temperature dynamics could be collected from a location other than the field, such as on the moving irrigation system itself. An artificial dry reference surface was tested to determine whether it could be used as the reference surface to capture the canopy temperature dynamics. The surface consisted of a large artificial plant leaf, cut to fit and mounted in a cross‐stitch hoop. This was located in a stationary position next to the field being studied. The temperatures of the artificial reference surface were measured with IRTs mounted both above and below it. Canopy temperature dynamics predicted from one time‐of‐day measurements using the artificial dry reference surface were compared to those predicted using living and transpiring canopy temperature measurements in a stationary location in the field. The absolute mean errors of the predicted diurnal curve from the actual measured curves were compared. The errors when using the artificial dry reference surface were significantly worse than those of the living crop. These errors were possibly due to the fact that the artificial dry reference surface was not located amongst the living canopy. Future experiments need to be done with the artificial dry reference surface located on the moving irrigation system but near or amongst the living canopy.

Select this Article		Irrigated Agriculture's Future with Increasing Food Demand and Growing Water Scarcity — EWRI PIAIP Task Committee Report Ronald D. Bliesner, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)286 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A Task Committee of the On‐Farm Irrigation Committee was formed to develop a mechanism to help put irrigated agriculture in perspective in the context of its use of fresh water and its role in world food production. At the 2005 EWRI Congress the task committee organized a series of technical sessions that dealt with the implications of irrigated agriculture with growing water scarcity, increasing food requirements, environmental sustainability and changing climate. A task committee report on the topic, written as a resource for policy makers, scientists, engineers and the popular press to aid in the understanding of these complex issues, is now in preparation. This paper summarizes the approach and initial findings of the report.

back to top

MODERNIZATION OF SMALL DISTRICTS

Select this Article		Converting Open Ditches into Underground Pipelines on a System with No Formalized Scheduling Michael Isaacson, P.E. and Andrew Keller, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)287 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In 2005, the San Juan River Dineh Water Users, Inc (SJRDWU) a newly organized water users association located on the Navajo Nation in Shiprock, NM, converted Loop Lateral, an earthen ditch, into an underground pipeline. Achievements by completing the conversion include introducing water management to an area with no formalized scheduling, improving the equitable distribution of water delivery, facilitating on‐farm development improvements implemented by subsistence farmers, and bringing validity to a fledging organization whose sole purpose is to receive the transfer of operations from a tribal government. The project was completed solely by SJRDWU, an independent Navajo corporation, on Indian trust land with partial assistance from the United States Department of Interior Water 2025 Challenge Grant Program, the Navajo Nation Department of Water Resources and from the Navajo Nation Department of Agriculture.

Select this Article		Operational Model of the Belle Fourche Irrigation District Tim Olson, Scott Kenner, and Dan Hoyer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)288 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Belle Fourche River, located in west‐central South Dakota and east‐central Wyoming, is currently listed in the South Dakota 2004 Integrated Report for Surface Water Quality Assessment as impaired because of elevated total suspended solids (TSS) concentrations. The goal of the Belle Fourche River Watershed Management and Project Implementation Plan (Segment II) is to reduce the TSS concentration by 55 percent within 10 years through the implementation of several best management practices (BMPs). The total maximum daily load (TMDL) report completed for the Belle Fourche River Watershed lists the Belle Fourche Irrigation District (BFID) as a major contributor to the TSS load. The elevated TSS load is a function of the delivery and application efficiency in the BFID where 64 percent of the water released from the reservoir is delivered to the field, 32 percent is used by the crops, and the rest is lost to evaporation and nonused water discharged into adjacent waterways. This paper focuses on the use of an operational model linked with a hydraulic model to improve the operational efficiency of the Belle Fourche Irrigation District and to reduce the TSS load 37 percent. The operational model is comprised of three main objectives. The first objective is to ensure the correct amount of water is delivered to the Vale Flume. The model will also eliminate the need for large surges of water to be released from the dam. Surges tend to increase the head at lateral gates and if the additional head is not accounted for, an unknown increase in water is discharged into the lateral. Finally, the operational model will provide operating procedures and rating curves for control check structures. This paper will discuss the three main objectives in detail.

Select this Article		Water Measurement and Management Initiatives in the Pioneer Irrigation Ditch Robert F. Einhellig, Tom Gill, Jack Wergin, and Dan Korf ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)289 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Pioneer Irrigation Ditch diverts water from the North Fork of the Republican River in northeastern Colorado near the town of Laird. The project was originally constructed in the 1890's and features 15 miles (24 km) of main canal which crosses the state line into Nebraska before terminating near the town of Haigler. With typical diversion rates ranging from 11 to 37 ft³/sec (0.31 to 1.0 m³/sec), the ditch provides water for approximately 2,600 irrigated acres (1100 ha) and 22 landowners in Yuma County, Colorado and Dundy County, Nebraska. Flow measurement for management and accounting purposes has historically been limited to diversion measurements near the project headworks, interstate transfer measurements in the main canal at the state line, and return flow measurements at the tail end of the project. These measurements are all accomplished using Parshall flumes. In 2003, extended drought conditions and recurring water shortages prompted the district to request assistance from the Bureau of Reclamation. Specifically, the district sought help with implementing water measurement and management practices throughout the system that would enhance water conservation and the equitable distribution of limited water supplies among the project recipients. A variety of low‐cost flow‐measurement options to quantify turnout deliveries were suggested to and implemented by the district over the following two years. These included simple weirs, submerged orifices, elbow meters, long‐throated flumes, propeller meters, and home‐made venturi meters. This effort resulted in decreased waste within the system and a more equitable distribution of water throughout the system—particularly to the users at the tail‐end of the system who had typically borne the brunt of any water shortages in the system.

back to top

QUALITY CONTROL OF AGRICULTURAL WEATHER NETWORK DATA AND USE IN WATER RIGHTS AND RESOURCE PLANNING

Select this Article		Real Time Weather Station Data Quality Control Procedures in the Alberta Agriculture Drought Monitoring Network (AGDMN) Daniel Itenfisu and Ralph Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)290 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Quality controlled weather data is a key component of a modern agricultural and food industry and environmental protection program. In order to meet the need for real‐time quality weather data in Alberta, the Alberta Agriculture Drought‐Monitoring program initiated the development of a standard automated weather station network across Alberta, known as Agricultural Drought Monitoring Network (AGDMN). The network started with 21 stations in 2001, and has grown to 40 stations with ongoing expansion plan of adding 60 more stations. Alberta Agriculture also makes uses of historical and near real time reported weather data collected by different agencies in the province. Effective design and operation of a modern weather monitoring networks should take a systems approach that considers all aspect of the weather stations network system ranging from station sitting, operation, maintenance and quality data reporting that meets the needs of potential users. A science based, reliable quality control and assurance procedure is vital in delivering credible quality data the users. While establishing and implementing a science based quality control and assurance procedure it is important to build on the experience of existing networks. This paper discusses the quality control and assurance procedure adapted by AGDMN to secure a high quality standard for its weather data that meets research quality data to be delivered o to users online. The quality control procedure consists of field visits, manual inspection, and a comprehensive computer routines combined with human intervention.

Select this Article		Crop Coefficients Developed at Bushland, Texas for Corn, Wheat, Sorghum, Soybean, Cotton, and Alfalfa T. A. Howell, S. R. Evett, J. A. Tolk, K. S. Copeland, D. A. Dusek, and P. D. Colaizzi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)291 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Crop coefficients derived from evapotranspiration measured with large, precise weighing lysimeters at Bushland, TX are presented for the major regional irrigated crops — corn, wheat, sorghum, soybean, cotton, and alfalfa. The ASCE/EWRI standardized reference evapotranspiration equation for daily weather data for short (ET_os, grass) and tall (ET_rs, alfalfa) crops was used as the base. Crop coefficients for both ET_os and ET_rs were summarized. They were generally in agreement with K_cb values from Davis, CA; Kimberly, ID; and from FAO‐56.

Select this Article		Footprint Analysis to Assess the Conditioning of Temperature and Humidity Measurements in a Weather Station Vicinity Richard G. Allen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)292 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Equations for estimating the influence of upwind fetch on air temperature and humidity measurements are applied to assess fetch impacts on agricultural weather stations. The equations are derived from flux and scalar footprint models and may serve as a first approximation of the amount of impact (F = 0 to 1) that upwind fetch distance has on measured air temperature or humidity at height z above the surface. This information is useful for judging adequacy of green fetch upwind of a weather station and for judging the amount of impact that a dry surface in the vicinity of a weather station has on measurements. The equations were applied to various fetch lengths of clipped grass and dry, bare soil over a range of wind speed. Results indicate that F increases more‐or‐less logarithmetically with fetch distance for both surface conditions and show F to increase with decreasing wind speed for a specified fetch distance. Results indicate that the 100:1 fetch distance:measurement height rule‐of‐thumb applies to unstable boundary layer conditions (positive Bowen ratio), but may underestimate the fetch requirement for neutral and stable conditions. Values for F for short fetch lengths, for example 5 and 10 m, show the fallacy of locating a weather station over a small area of grass or other vegetation, but surrounded by dry, poorly vegetated further upwind. Essentially none of the sensor signal (T and e measurement) is conditioned by the grass when wind speed is greater than 2 m s⁻¹.

back to top

REMOTE SENSING APPLICATION TECHNOLOGIES FOR ESTIMATING VEGETATION WATER USE I

Select this Article		Remote Sensing and Water Balance Modeling in California Drip‐Irrigated Vineyards L. Johnson, L. Pierce, A. Michaelis, T. Scholasch, and R. Nemani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)293 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Advanced computing technologies are being developed to combine remotely sensed imagery with ancillary data for production of ecological and agricultural “nowcasts” and forecasts. NASA's Terrestrial Observation & Prediction System (TOPS) uses Earth‐viewing satellite imagery to generate data fields related to hydrology, meteorology and ecosystem structure and function over regional to global extent, with products posted to the Internet on a daily‐to‐weekly basis. During the 2005 growing season, TOPS operated in conjunction with a water balance model and high resolution satellite imagery to generate daily nowcast/forecast maps of crop evapotranspiration (ET), soil moisture (SM), and leaf water potential (LWP) throughout a 400 ha California winegrape vineyard. The prototype was designed to enhance grower understanding of the effects of climate, soil water holding capacity, and crop vigor on such crucial factors as soil moisture, crop water stress, and irrigation demand.

Select this Article		Performance of Crop Coefficients Inferred from NDVI Observations for Estimating Evapotranspiration and Irrigation Scheduling of Wheat D. J. Hunsaker, P. J. Pinter, Jr., T. R. Clarke, G. J. Fitzgerald, and A. N. French ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)294 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Time‐based crop coefficients are often used to estimate daily crop evapotranspiration (ET_c) for determining irrigation scheduling. Incorporating remote sensing observations to infer crop coefficients during the season could provide the spatial and temporal estimation of ET_c that is needed for precise irrigation scheduling. Experiments conducted for two seasons with wheat investigated the use of reflectance‐based and time‐based basal crop coefficients (K_cb), integrated within the FAO‐56 dual crop coefficient framework to compute the daily ET_c for determining irrigation scheduling. The experiments consisted of two main treatments denoted as the normalized difference vegetation index (NDVI) and the FAO treatments. Six, replicated sub‐treatments, equally embedded within the two main treatments, included three plant densities (typical, dense, and sparse) and two nitrogen levels (high and low). NDVI data obtained from frequent ground‐based canopy reflectance measurements were used to calculate the K_cb for each NDVI plot via a previously defined relationship mat describes K_cb as a function of scaled NDVI. A single time‐based K_cb curve, developed locally for standard crop conditions, was used to estimate the daily K_cb for the FAO treatment plots. Predicted K_cb compared favorably with derived K_cb determined from field measurements for both the NDVI and FAO methods for standard conditions (typical density and high N) during the first season. However, the time‐based FAO K_cb curve failed to adequately describe derived K_cb for any sub‐treatment condition during the second season when crop development was atypical due to a late crop emergence date, delayed nitrogen applications, and a shorter growing season. Because the NDVI K_cb closely tracked derived K_cb for all sub‐treatments, ET_c prediction for NDVI was superior to FAO, particularly during the second season. In either season, the differences between the NDVI and FAO treatments for grain yield and water use efficiency (yield/ET_c) were not statistically significant. However, compared to the standard FAO K_cb curve, the NDVI‐K_cb method resulted in a significant decrease in the irrigation water used.

Select this Article		Estimation of Spatially Distributed Evapotranspiration over Wheat Using Thermal Infrared Images and Ground‐Based Radiometers Andrew N. French, Douglas Hunsaker, Thomas R. Clarke, Glenn J. Fitzgerald, and Paul J. Pinter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)295 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Spatially distributed evapotranspiration (ET) estimation is important for crop stress and assessment and irrigation scheduling. Using remotely sensed thermal infrared data in combination with visible‐near infrared data, accurate instantaneous ET estimates are feasible. These estimates, however, need to be extended to daily time steps to have practical value at farm scales. One way to accomplish this extension is to combine hourly image observations of soil and vegetation temperatures. This approach is tested using a one‐source energy balance model and data obtained from a series of morning remote sensing flights on 10 March 2005 over a wheat crop planted in Maricopa, Arizona. Aggregate remote sensing ET results from this particular day agreed well with estimates derived from soil moisture observations, but not on a plot‐by‐plot basis, where modeled ET variability was much less than soil moisture variability. This result is inconsistent with remotely sensed surface temperatures which do show significant spatial and temporal changes. Additional data sets will be investigated to determine how to improve ET modeling with surface temperatures.

Select this Article		Estimating Riparian ET through Remote Sensing in the Middle Rio Grande Salim Bawazir, Zohrab Samani, Thomas Schmugge, Max Bleiweiss, Rhonda Skaggs, and Maritza Macias ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)296 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Riparian evapotranspiration (ET) along the Rio Grande River has become a major hydrological as well as political issue in New Mexico. The State of New Mexico has spent millions of dollars in recent years to eradicate riparian vegetation without being able to quantify the change in regional ET. Many studies have focused on measuring ET of individual riparian vegetation types, mainly saltcedar and native cottonwood. However, the riparian vegetation in the Middle Rio Grande varies in density and species. Spatial variations in climate, soil type and depth to groundwater causes variations in ET, as well. It is obvious that in order to obtain more accurate measurements, multiple sampling points are needed; thus, making the process costly and impractical. An alternative solution, which is also cost‐effective, is to use remotely sensed data to estimate ET over large areas. This remote sensing approach combines regional satellite data with localized ET measurement to calculate regional ET. REEM (Regional ET Estimation Model) is a process that uses the energy balance at the top of the canopy to estimate ET. REEM uses data from the Advanced. Spaceborne Thermal Emission and Reflection radiometer (ASTER) on board NASA's Terra satellite. These data are: surface temperature, albedo and NDVI to calculate net radiation (Rn), ground heat flux (G) and sensible heat flux (H). The ET is then calculated as the residual of the energy components. The REEM model was used to calculate regional ET values for the Riparian vegetation of the Middle Rio Grande. This paper compares the ET values for various vegetation types (saltcedar and cottonwood) using remote sensing and ET derived from Eddy Covariance Flux Towers.

Select this Article		Use of Crop Canopy Size to Estimate Crop Coefficient for Vegetable Crops Thomas Trout and Jim Gartung ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)297 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Planting time, plant density, variety, and cultural practices vary widely for horticultural crops. It is difficult to estimate a basal crop coefficient that can incorporate these variations. Canopy cover, as an indicator of intercepted sunlight, is related to crop water use. We used a weighing lysimeter to measure daily crop water use and a multi‐spectral camera to measure canopy cover for two vegetable crops — head lettuce and bell pepper, and related canopy cover to basal crop coefficient. The ratio of crop coefficient to canopy cover declined from about 4 with small canopy cover (0.1) to about 1.3 for a mature crop with canopy cover of 0.9. The relationship was similar for these two crops. Because light interception other than at mid‐day will depend on the canopy structure, adjustment may be needed for canopy structure. A generalized canopy cover:basal crop coefficient relationship would allow weather‐based irrigation scheduling for a wide range of horticultural crops based on canopy measurements, and possibly based on remotely‐sensed vegetation indices.

Select this Article		Mapping Contrasting Tillage Practices in the Texas Panhandle with Landsat Thematic Mapper (TM) Data P. H. Gowda, R. T. Peters, and T. A. Howell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)298 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Tillage information is crucial in environmental modeling as it has a direct impact on soil erosion and water holding capacity of agricultural soils. A remote sensing approach is promising for the rapid collection of tillage information on individual fields over large areas. In this study, six Thematic Mapper (TM)‐based logistic regression models proposed by van Deventer et al were used to distinguish conventional and conservation tillage practices in Ochiltree County located in the Texas panhandle. Accuracy assessments of tillage maps derived from Landsat 5 TM data were made using field data collected during the 2005 planting season. Logistic regression models were easy to use, cost and time effective, and produced reasonably accurate tillage maps. The “percent correct” and kappa (k) values varied from 61–83% and 0.02–0.73, respectively, with best values for logistic regression models that use TM bands 1, 3 and 5 images. This approach is promising for the rapid collection of tillage information on individual fields over large areas.

back to top

REMOTE SENSING APPLICATION TECHNOLOGIES FOR ESTIMATING VEGETATION WATER USE II

Select this Article		Evaluation of a Two‐Source Energy Balance Model in an Advective Environment P. D. Colaizzi, S. R. Evett, T. A. Howell, J. A. Tolk, and F. Li ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)299 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A two‐source energy balance model (TSEB) was evaluated in terms of latent heat flux (LE) for six crops, wheat stubble, and bare soil in an advective environment, and net radiation (R_n) was modeled both with and without separate transfer characteristics used for visible and near‐infrared radiation. Observed (i.e., ground‐truth) LE was derived from changes in mass measured by precision weighing lysimeters averaged to 0.5‐h, and observed R_n was measured by net radiometers at the lysimeters. Agreement between observed and predicted R_n was not greatly influenced by separation of visible and near‐infrared radiation, possibly because constant soil albedo was assumed for visible and near‐infrared wavelengths. The TSEB tended to overestimate LE for smaller observed LE (< ∣400∣ W m⁻²) by up to 200 W m⁻², but relative error improved as observed LE increased and appeared not to be influenced by strong regional advection.

back to top

WATER QUALITY AND AGRICULTURAL DRAINAGE IN HUMID REGIONS

Select this Article		Evaporation — A Tool for Sustainable Drainage Management Peter Worrall, Steve Markham, and Quintin Murfin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)300 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Where the use of orthodox controlled hydraulic discharge to watercourse is not possible for the management of urban runoff, alternative strategies need to be considered. At Jersey Airport (Great Britain) the development of a new Fire Training Ground facility was constrained by a prohibition on the disposal of surface runoff to watercourse or ground water (because of low levels of persistent pollutants in the runoff) so a system using evaporation and water re‐use was developed to create a unique surface water drainage system without a surface water outfall. Surface runoff from the training ground catchment, excluding that generated during practice, is contained and stored beneath the permeable paved surface in a storage cell and managed either through evaporation or through harvesting for use in fire fighting practice. Evaporation is achieved using a patented system of 20 water jets placed around the fire training ground that apply water from the cell to the paved surface. They are automatically switched on when the on‐site weather station indicates that there is sufficient evaporative potential. Wind speed and direction are measured to enable the sprays to cover the paved areas within the site boundary. Further research has been undertaken that has demonstrated that significant evaporation is achievable in patented designs of underground storage cells. This paper describes the development and modelling of the use of evaporation as a runoff management tool with particular emphasis on spray‐on‐pavement systems and enhanced passive evaporation from underground storage cells. The use of spray on pavement systems has been proven as viable and the use of in‐cell evaporation is under development.

Select this Article		Experimental Investigation of Direct Connectivity between Macropores and Subsurface Drains during Infiltration Onur Akay and Garey A. Fox ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)301 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Laboratory experiments are commonly utilized for investigating the effect of macropore flow on contaminant transport. Most research to date has focused on lateral water and solute diffusion between macropores and the soil matrix with controlled bottom flux or specified pressure head boundary conditions as opposed to simulating local drainage flux to tile drains. Furthermore, recent research indicates immediate breakthrough of solutes and pesticides in subsurface drainage by extraordinarily efficient transport through directly connected macropores. Macropores, such as those created by earthworm burrows, have been documented to transfer water and solutes directly to subsurface drains. In this study, this “direct connectivity” phenomenon was verified by conducting infiltration experiments in a laboratory column (28 cm by 50 cm rectangular cross‐section with length of 95 cm) with an artificial macropore directly connected to the subsurface drain. A novel design of the experimental setup allowed open surface and buried macropore lengths to be varied from the subsurface drain to the surface without unpacking/disturbing the soil column between experiments. Experiments were completed for various buried macropore lengths ranging from zero (no macropore effect) to 75 cm (surface connected macropore). The column was packed with a sandy loam soil with bulk density of 1.6 g/cm³. For each experiment, a 1‐cm ponded boundary condition was maintained at the soil surface. Breakthrough curves were plotted for both matrix and macropore flow at the outlet. The movement of the wave front down the column was observed with pencil size tensiometers mounted on the side of the column at various depths. The macropore and soil matrix outflow revealed hydraulic nonequilibrium between soil matrix and macropore domains. It was observed that the longer the buried macropore length (i.e., as the macropore approached the soil surface), the more rapid response occurred at the drain outlet in addition to an increased percentage of total drain flow through the macropore. Breakthrough times with the surface connected macropore decreased significantly compared to buried macropores. This research also suggests that “drain connected” macropores may not necessarily have to possess a direct physical connection to subsurface drainage.

Select this Article		Potential for Reducing Nutrients from the Poultry Industry in the Chesapeake Bay Watershed William F. Ritter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)302 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Over 800,000 million broilers are raised in the Chesapeake Bay watershed. Together with turkeys and laying hens, poultry production is a major source of N and P loads that are transported to the Bay from agriculture. Nutrient management planning, phytase addition to feed, use of high available P corn and pellitizing the litter are the most promising BMPS for broiler for reducing N and P loads. Nutrient management planning, composting, pellitizing, and using layer hen manure for mushroom substrate are the most promising BMPs for laying hens.

Select this Article		Tillage and N‐Source Effects on NO₃‐N Leaching Losses to Subsurface Drainage Water A. Bakhsh and R. S. Kanwar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)303 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An appropriate combination of tillage and source of nitrogen fertilizer can reduce NO₃‐N leaching losses to subsurface drain water. A field study was conducted from 1999 through 2003 on tile drained fields to determine the effects of liquid swine manure (LSM) application under, no‐till (NT) and urea ammonium nitrate (UAN) application under chisel plow (CP) on corn [Zea mays L.] and soybean [Glycine max (L) Merr.] yield and NO₃‐N leaching losses with subsurface drain water. Four treatments of LSM (165 kg‐N ha⁻¹) with NT and UAN (170 kg‐N ha⁻¹) with CP applied to corn were replicated three times in a randomized complete block design. Seasonal effects were found to be significant (P<0.01) and above normal rainfall during the growing season for the months of July and August in 2002 resulted in highest corn and soybean yields of 12 Mg ha⁻¹ and 3.6 Mg ha⁻¹, respectively, with minimum NO₃‐N leaching loss of 3 kg‐N ha⁻¹. The LSM with NT plots in comparison to UAN application to CP plots resulted in significantly (P<0.01) lower flow weighted average NO₃‐N concentrations (12 vs. 16 mg L⁻¹) due to dilution effects of greater subsurface drainage volume from NT plots by 73% (142 vs. 82 mm). Treatment effects on corn‐soybean yields and NO₃‐N leaching losses were not significant but LSM with NT gave higher NO₃‐N leaching losses in comparison with UAN under CP treatment (15 vs. 11 kg‐N ha⁻¹).

Select this Article		The Nitrogen Simulation Model, DRAINMOD‐N II: Field Testing and Model Application for Contrasting Soil Types and Climatological Conditions M. A. Youssef and R. W. Skaggs ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)304 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract DRAINMOD‐N II is a field‐scale, process‐based model that simulates nitrogen dynamics and turnover in drained croplands under different management practices and soil and environmental condition. This paper summarizes results of testing the model using data sets from two drained agricultural sites with contrasting soils, climatic conditions, and management practices. One site is located in North Carolina and the other site is located in Indiana. It also summarizes results of long term simulations conducted using calibrated model inputs to study the effects of drainage design and management and N fertilization rates on NO₃‐N leaching losses under the local soil and climatic conditions of each site. Results of the two field evaluations indicated that the model accurately predicted annual and cumulative NO₃‐N losses from both sites. Model predictions for the IN site were more accurate than model predictions for the NC site. Results of the long term simulation studies demonstrated the strong influence of the N fertilization rates on N losses from drained croplands. It also indicated the influence of drainage design (drain depth and spacing) and management (drainage control) on N leaching losses. The predicted response of the soil‐water‐plant system at each site to different drainage water and N fertilization scenarios was influenced by local soil and climatic conditions. These results indicated that DRAINMOD‐N II can be reliably used in the development and evaluation of drainage water and agronomic management practices that reduce N losses from drained agricultural lands.

back to top

VISIONS FOR NSF ENVIRONMENTAL OBSERVATORIES I

Select this Article		The New England Coastal Basins Observatory: Documentation of Hydrologic Transport Processes D. W. Ostendorf, P. S. Rees, and S. M. Doerner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)305 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The New England Coastal Basins Observatory is a proposed response to the NSF Environmental Observatories Initiative. The Observatory functions now as $7 million of field research in the Blackstone River and Plymouth‐Carver Aquifer by the Civil and Environmental Engineering Department of UMass Amherst. Observatory assets also include Long Term Ecological Research sites at Hubbard Brook, NH and Plum Island, MA and the Microwave Remote Sensing Laboratory of UMass Amherst. This core will expand to a consortium of universities, government agencies, and private organizations across New England. The Observatory will study transport processes across hydrologic boundaries at field research sites in New England Coastal Basins over a cascade of length and time scales. Ongoing, proposed, and future research illustrate the Observatory approach, which will include conventional investigations of water distribution through watersheds, rivers, and reservoirs. The Observatory will extend the Initiative however by measuring the transport of contaminants, momentum, and sediment across interfaces between the surface water, groundwater, atmosphere, and nearshore environments in the Basins. Deicing agent ions and isotopes will serve as hydrologic tracers to document the age and trajectory of the flow field. Metal fate and transport, shear stress, storm surge, and coastal erosion will emerge as field documented, hydrologic phenomena at hourly, diurnal, seasonal, and annual scales. The cascade of scales and constituent data will support independent calibrations of common transport coefficients.

back to top

VISIONS FOR NSF ENVIRONMENTAL OBSERVATORIES II

Select this Article		Water QUEST: Center for Water Quality in Urban Environmental Systems J. M. VanBriesen and D. A. Dzombak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)306 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In response to the need for greater understanding of water quality in urban systems, Carnegie Mellon University has launched the Center for Water Quality in Urban Environmental Systems (WaterQUEST). The goal of this center is to advance the scientific basis for management of inputs and inventories of contaminants in urban watersheds. WaterQUEST will involve several critical components: (1) primary research on environmental sources and fate of contaminants of concern in urban systems (e.g., pathogens, persistent toxicants), (2) development of necessary monitoring and modeling capabilities for urban watersheds, (3) development of technologies and modeling tools for improved management of water quality in urban systems, and (4) outreach and education to develop a citizenry ready for the challenges of managing urban water systems. Located at Carnegie Mellon University in the heart of Pittsburgh, WaterQUEST will use this urban area as a laboratory for research and development.

back to top

COLLABORATIVE MODELING FOR WATER MANAGEMENT

Select this Article		Informed Consent through Collaborative Modeling and Transparent Decision‐Making: The Lake Ontario St Lawrence River Study Mark Lorie ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)307 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The now completed International Lake Ontario — St Lawrence River Study involved continuous feedback and communications between technical experts, stakeholders, representatives from the general public, and the policy‐makers charged with crafting final recommendations. A Shared Vision Planning approach was used to structure this process, with the collaborative development and implementation of a transparent computer model used to formulate and evaluate water quantity management strategies. Use of the Shared Vision approach allowed for an open debate over this multi‐objective management problem using the some of the best scientific information available. The goal of the Shared Vision Planning approach was to produce a state of informed consent — a state in which stakeholders accept the analytical results of a planning process and the tradeoffs inherent in final decisions, even if those decisions do not provide their preferred outcomes. The means used to achieve this goal, and the degree to which the goal was achieved, will be discussed.

back to top

INTEGRATED CATCHMENT STUDY OF AUCKLAND CITY, NEW ZEALAND

Select this Article		The Integrated Catchment Study of Auckland City (New Zealand): Fate of Contaminants in Coastal Receiving Environments M. G. V. Bogle, A. E. Croucher, M. J. O'Sullivan, M. D. Davis, P. Kinley, B. Sharman, and G. Paterson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)308 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Coastal Receiving Environment Assessment (CREA) forms part of the Integrated Catchment Study (ICS) of Auckland City, New Zealand. The scope of CREA included modelling the fate of contaminants discharged from Auckland City and adjacent councils to coastal receiving environments in the Waitemata and Manukau Harbours to assist in assessment and mitigation of public and ecological health risks. Hydrodynamic, particle tracking and contaminant accumulation models were used as the basis for numerical model predictions of long‐term sediment and particulate zinc accumulation in the coastal benthos. The modelling approach included the effects of settling, re‐suspension, wind wave‐induced bottom shear stresses and bioturbation. The contaminant accumulation model was used to project long term zinc accumulation and investigate relative impacts of different stormwater quality improvement scenarios. Upper and mid‐Whau and Tamaki Estuaries contain high levels of zinc that are expected to continue to rise under most feasible contaminant reduction scenarios. Reduction scenarios can result in improvement in zinc accumulation in some outer settling zones and decreased zinc discharge to middle harbour areas. Results from CREA provide information about the potential benefits of contaminant reduction scenarios, facilitating investigation of options and management practices in targeted locations in upstream catchments where infrastructure investment can be most effectively directed.

Select this Article		The Integrated Catchment Study of Auckland City (New Zealand): Contaminant Load Discharge to Coastal Receiving Environments Matthew D. Davis, Peter Kinley, Jacquie Reed, Mike Timperley, Geoff Wilson, Brian Sharman, and Greg Paterson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)309 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Contaminant loads were computed as part of the Integrated Catchment Study (ICS) of Auckland City (New Zealand). Overflows and stormwater from 29,000 hectares discharge through 3,000 outfalls to the Waitemata and Manukau Harbours. Enterococci, total suspended sediment and total zinc pollutographs were produced at 81 consolidated outfalls by combining outputs from (1) combined and wastewater overflows from network modelling and (2), consolidated catchment stormwater quality modelling. The extent of network models was based on addressing key issues, including designed overflow structure locations and principal sources of stormwater contamination. 35 to 80% of the public pipe network was modelled in each catchment, totalling 43,000 nodes. Network models were developed in MOUSE and calibrated and validated to nearly 350 flow and rain gauges. Rainfall‐runoff was simulated with the Model B + RDI module, reflecting a combination of kinematic wave plus rainfall dependent inflow methods. Pipe hydraulic routing was calculated solving the St. Venant equations, with the energy equation applied at manholes. Overflow contaminant loads were generated by factoring combined and wastewater overflow volumes by a Volume Weighted Wastewater Event Mean Concentration method. Stormwater loads were produced by combining consolidated catchment MOUSE hydrographs with STORMQUAL, an urban stormwater quality model. STORMQUAL is based on contaminant build‐up and wash‐off. Model parameters were calibrated to commercial, industrial, and residential land uses from monitored subcatchments. Parameter values estimated from monitored land uses were regionalised based on the known mix of land use in unmonitored consolidated catchments. The largest enterococci discharges occur from outfalls in the older parts of the city that contain substantial portions of combined networks and large number of designed overflow structures. Industrial areas containing zinc coated roofs discharging to the Whau Estuary, Waterview Inlet, Tamaki Estuary, and One Tree Hill contribute the largest zinc contaminant loads in the city.

Select this Article		The Integrated Catchment Study of Auckland City (New Zealand): Overview Brian Sharman, Greg Paterson, Roger Brown, Matthew D. Davis, Peter Kinley, and Sandip Ranchhod ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)310 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The NZ$23.5 million Integrated Catchment Study (ICS) was a four‐year study whose objective was to develop a comprehensive understanding of the Auckland Isthmus drainage systems and receiving environments, and to develop decision‐making tools to enable the following to be achieved: (1) prioritised investment decisions based on triple bottom line (economic, environmental and social), (2) management decisions and planning now and in the future to 2050 and (3) support for Auckland City Council and Metro Water Limited's drainage network resource consent applications to Auckland Regional Council. The ICS was a computer modelling focused study to assist Auckland City and Metrowater to develop robust understanding and solutions to address: (1) wet weather combined and wastewater overflows that can create short‐term public health issues, (2) habitable floor flooding that can produce economic loss and public health issues, (3) stormwater quality that can produce long‐term environmental health issues and (4) provision for growth, which can exacerbate drainage issues. The study was performed in three stages: (1) data capture, (2) catchment analysis (model development and system performance) and (3) options analysis and reporting. Computer models were developed for the (1) integrated wastewater, combined, and stormwater surface and piped networks, (2) groundwater aquifers and (3) coastal receiving environments. Key outcomes of the ICS and related studies include identification of (1) habitable floors subject to flooding, (2) contaminant loads, (3) elevated public health risks at beaches up to 48 hours after rain events, (4) a combination of subcatchment sewer separation and storage / maintenance of combined systems as preferred drainage solutions, (5) trunk wastewater solutions in the Central City subject to continued Joint Planning with Watercare (regional provide) to resolve trunk sewer issues, (6) zinc as the principal contaminant of concern, with zinc coated roof source control as the preferred solution, (7) groundwater aquifer capacity to accept more than double current stormwater disposal, (8) additional stormwater disposal to aquifers that is not expected to adversely affect other groundwater uses.

Select this Article		The Integrated Catchment Study of Auckland City (New Zealand): Long Term Groundwater Behaviour and Assessment Parviz Namjou, Gerald Strayton, Alan Pattle, Matthew D. Davis, Peter Kinley, Paul Cowpertwait, M. Jim Salinger, A. Brett Mullan, Greg Paterson, and Brian Sharman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)311 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Long term groundwater behaviour under existing and future scenarios in a fractured basalt aquifer system is presented for Auckland City (New Zealand). The Auckland Isthmus is comprised of unconfined basalt aquifers and semi‐confined Waitemata and Tauranga Groups (sandstone and mudstone) aquifers. The basalt aquifers are used to dispose stormwater via soakholes, provide groundwater supply in Onehunga and other industrial and commercial sites, constitute baseflow in Motions and Meola Creeks and feed important springs in Western Springs and Onehunga. Regional groundwater models were developed in Visual MODFLOW and MIKE‐SHE, covering approximately 45 km² with a north‐south grid alignment and 100 × 100 m grid cells. Vertically the models are divided into a single basalt aquifer hydrogeological unit. The models were calibrated to five years of historical records. Two long term scenarios and were simulated: (1) existing conditions (20‐year simulation with current climate and existing development land use) and (2) future conditions (15‐year most probable 2050 climate and maximum probable development 2050 land use). Spare capacity exists in the aquifers to accommodate additional stormwater disposal. Additional groundwater breakout (surface flooding) is predicted in expected areas during high rainfall recharge years. Stream and spring flows, and groundwater supply are not anticipated to be adversely affected by groundwater management recharge practices. A major unresolved issue is to find practical ways to capture and inject large volumes of stormwater generated over short, high intensity storms.

back to top

TRENDS IN STATE WATER RESOURCES PLANNING — PANEL

Select this Article		An Evaluation of Public‐Private Partnerships for Water and Wastewater Systems Patrick Cairo and Christopher Frangione ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)312 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Public‐private partnerships (PPPs) are one tool a municipality can use to become more efficient in running their water and wastewater operations. Under PPPs, the public partner owns the assets, controls the management of the assets, and establishes user rates. The private partner operates and maintains the facility under a contract with the public partner. The use of public‐private partnerships for water and wastewater services in the United States has been both praised and challenged. However, until recently, neither point of view has been supported by quantitative data. In early 2005, The Water Partnership Council (WPC) undertook what may be the first‐ever municipal survey to quantify the benefits of PPPs. The survey results are based on 31 interviews with representatives of public entities that contract the day‐to‐day management, operation, and maintenance of their water and/or wastewater facilities to a private partner—in whole or in part. The facilities serve populations ranging from 4,000 to 1.2 million. The total population covered by the surveyed partnerships is 4.7 million. The municipalities surveyed enter into public‐private partnerships to save money, gain operating expertise, and improve compliance with environmental regulations. According to the survey results, municipal satisfaction with partnerships is high, employees are satisfied, and impacts on the environment, customers and the community are positive.

Select this Article		Brazil Water Resources Management: Evolution and Challenges Maria Edelcides Gondim de Vasconcelos ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)313 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Brazil is a federal republic of South America known as a country of plentiful water. Approximately 13% of the world's surface water resources are in Brazil. This perceived abundance delayed the realization of its scarcity and the need for it to be managed. The Water Code, in 1934, initiated the Brazilian legislation in water resources. A centralizing model that emphasized the utilization of water to generate energy but neglected other uses. The Law 9,433, in 1997, defines a new paradigm — integrated, decentralized management of water resources with user participation. The continental dimensions of the country, together with its ecology and organizational structure, present great challenges for the implementation of this new management model. The institutional instruments as the State Water Resource Councils were installed in many places, except in Roraima, a state in the North of Brazil. However, the Basin Committees that legitimate the participative and decentralizing management are practically present only in basins of the southern and southeastern regions. Only eight states among the 26 of the federation present a State Planning of Water Resources. Although the grant of water use is instituted in almost all states, the criteria have not been defined by the Basin Committees and are based on quantitative hydrologic information with no debate on the preponderant use of water in the region. To support Brazil Water Resources Management two great programs are already in course. The Water Program (PROAGUA) aims at increasing good quality water supply in the semi‐arid, northeast region in Brazil. The River Basin Pollution Abatement Program (PRODES) was created aiming at both preventing river basin pollution as well as reducing the existing water pollution levels in the river basins. The aim of the Brazilian managing system is turned to scarcity and it meets the Northeast, with problems related to droughts, and South and Southeast with water quality problems. The management instruments, even implemented, are insufficient to meet the premises of a sustainable management model. Overcoming the challenges will require that the water basin concept, as a planning and management unit, become operational, especially on rivers under both federal and state domain.

Select this Article		Economic‐Engineering Theory of Flood Levee Height and Setback Tingju Zhu and Jay R. Lund ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)314 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Levee setback (location) and height are important issues in flood levee system design or modification. This paper derives an economic‐engineering theory of the optimal trade‐off of levee setback for height for both original and re‐designed flood levees, demonstrating the interconnection of levee setback, height, costs and risks, and economically optimal decisions. All the analyses assume that hydrologic and economic conditions are “static”. Expected total flood control costs are shown to be convex for conditions of wide channels where flood flows have a lognormal frequency distribution. The re‐design rules derived in this paper hold for much wider conditions. Numerical examples illustrate the results. This paper demonstrates several ideas and theory for economic flood levee system planning and policy rather than providing guidelines for direct design practice.

Select this Article		Management of Interstate/International River Basins in a Multidimensional Society Nani G. Bhowmik, Ph.D., P.E., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)315 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The majority of the world's river basins do not adhere to political, geographical or human‐imposed boundaries. Even in a large country such as the United States, where many large rivers cross state boundaries, each state may have different needs and requirements. The degree of uncertainty between expectations of varying interest groups becomes even more pronounced when a river crosses an international boundary. For example, the needs of upstream riparian residents may be completely different than those of downstream residents. In many cases, the countries may work out a reasonable solution to these difficult problems. Overall, it is prudent for all the concerned entities, states, and/or countries to follow some basic concepts and principles to develop a solution that is acceptable to all parties. The present paper outlines several such concepts and principles for management of large rivers such as the Kankakee and Mississippi Rivers in the United States, and the Ganges and Brahmaputra Rivers in Asia. A procedure also will be outlined to develop a reasonable, acceptable solution for integrated management of large river basins. River managers and engineers should keep in mind several points: each river basin is unique; river management must benefit people in the basin; priorities of various users may be differ; a basinwide institutional framework must be implemented; concepts and ideas must be developed for total river basin management; water in all forms must be shared among people in the basin; human health and environmental needs must be an integral component; and, finally, any and all management options must incorporate monitoring and data collection for use in the ultimate concept of “adaptive management.”

back to top

APPLIED RESEARCH POSTERS

Select this Article		New Dynamically Dimensioned Search Algorithm for Automatic Calibration with Application to Phosphorous Transport in Northeast Watershed Christine A. Shoemaker and Bryan Tolson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)316 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes an oral presentation that will discuss new algorithms for calibration, sensitivity, and uncertainty analysis in complex environmental models. The optimization portion of the algorithms addresses both local and global optimization. The results of the analysis are applied to the modeling of flow and Phosphorous transport in a large watershed in the northeast.

Select this Article		A Theoritical Model Development — Effect of Initial Phenol Concentrations on Phenol Degradation by Using Pseudomonas Putida Cells Immobilized on Calcium Alginate Matrix M. Mahadevaswamy, I. M. Mishra, B. Prasad, and I. D. Mall ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)317 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Bio‐kinetic model was developed for immobilized whole‐cells using Briggs‐Haldane equation incorporating the substrate inhibitory effects for Gaden Type — I fermentations. Model equations also include the effectiveness factor concept and the reaction contribution in liquid space as well as immobilization matrix, for exponential and equilibrium stage growth phases. The model equations were verified using batch experimental data obtained for a phenol degradation by Pseudomonas putida immobilized on calcium alginate matrix and the bio‐kinetic parameters were determined. Batch immobilized whole‐cells experimental data reveals that variation in the initial phenol concentration have significant effect on the time taken for degradation of phenol. Also effectiveness factor increases with increase in initial phenol concentration under exponential as well as equilibrium growth phases.

Select this Article		Three‐Dimensional Model Analysis of Pier Scour Hydraulics: A Supplement to Experimental and Field Investigations Ahmed A. Kassem ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)318 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A three‐dimensional computational fluid dynamics (CFD) model is utilized to supplement experimental and field investigations for the evaluation of a new laboratory‐based methodology developed to estimate the ultimate pier scour in cohesive soils. The method is applied to three bridge sites with different pier configurations. Due to the absence of real‐life data on the flow field prevailing during the flood event that caused the scour, the model is used to reproduce such flow details around the bridge pier. In these simulations, the scour hole surveyed in the field at each site is employed in the model and the bottom shear stress distribution inside the hole is computed. The shear stress estimated by the new methodology from the scale model study is scaled up to the field scale and compared with the shear stress computed by the numerical model. The computed shear stress shows usefulness in evaluating the new methodology and assessing the ultimate condition of the pier scour.

Select this Article		Groundwater Plume from an Infiltration Basin D. W. Ostendorf, C. Rotaru, and E. S. Hinlein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)319 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract We model and measure the groundwater plume from an infiltration basin in the Plymouth‐Carver Aquifer near State Route 25 in southeastern Massachusetts. The advective transport model superimposes axisymmetric basin hydraulics and two dimensional ambient flow. The basin component incorporates a surface source of finite radius into a Hankel transform model for unconfined aquifers, while the ambient component varies linearly in the horizontal and vertical directions. Contaminant streamlines describe the resulting groundwater plume. Deicing agent constituent data confirm the plume boundaries, and calibrate plausible source concentrations and spread rates.

Select this Article		Using Fluorescence Spectrum to Differentiate Natural and Man-Made Organic Compounds in Water Environment J.-J. Horng and C.-L. Tang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)320 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The fluorescence spectrum has long been used in various investigations on natural organic matters (NOM) or dissolved organic matters (DOM) freshwater, coastal and marine waters as well as wastewaters and groundwater. By comparing the synchronous excitation and emission (EX-EM) fluorescence spectrum (FS), this study develops a method to distinguish some natural and man-made pollutants, including antibiotics and humic acids, from some surface water, groundwater, and wastewaters. The locations and finger prints of fluorescence spectra indicated either special function groups and the existence of chemicals of humic acids and antibiotics. A developed computer routine permitted the operation of digitization and background adjustment of spectrum to enable the species and concentrations determination. The identification for species correction could achieve 95 per cent in multi-component analysis. With minimum or no preparation of water samples, the detection limits for different chemicals varied from several ppm to 30 ppb with relatively good correlation in single or multi-component analysis (correction from 0.55 to 0.99). Although there are some problems on accurate determination of concentrations of target chemicals, this study develop a qualitative identification method of humic acids and antibiotics in water samples from fluorescence spectrum and further extended peak positioning and statistical analysis to graphic identification. Future studies should focus on identifying function groups of chemicals and quantifying concentrations in order to rapid and accurately detect the pollutants and their fates in the environment.

back to top

SUSTAINABLE DEVELOPMENT POSTERS

Select this Article		Life Cycle Assessment (LCA) as a Framework for Addressing the Sustainability of Concentrated Animal Feeding Operations (CAFOs) Troy A. Doby, Michael Gonzalez, and MaryAnn Curran ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)321 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The challenges Concentrated Animal Feeding Operations (CAFOs) directly pose to sustainability include their impact on human health, receiving water bodies, groundwater, and air quality. These challenges result from the large quantities of macronutrients (carbon, nitrogen, and phosphorus), micronutrients (sulfur and heavy metals), and antibiotics contained in the effluent from CAFOs. Technologies exist to deal with the challenges CAFOs present. We evaluate how Life Cycle Assessment (LCA) may be used to evaluate the gaps in knowledge when combining technologies currently available for dealing with the sustainability of CAFOs.

Select this Article		Construction of Water Saving Society in China Jian Liu, Ph.D., M. ASCE, Peng Lou, Minghua Huang, and Wen Xiao, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)322 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The water pollution and shortage have imperiled the living environment and the economic development. In order to solve the water shortage effectively, the Chinese government is making an appeal to the citizens for saving water and constructing a water saving society, except for construction of the giant South to North Water Transfer Projects to be completed in 2010. The essence of the water saving society is developing a water resources management system on the basis of water right and water market theory. The operation mechanism of constructing the water saving society and experiences are introduced, taking Dalian, Mianyang and Zhangye cities as examples. The amount of water usage can get the valid control by constructing the water saving society and making comprehensive use of water resources. Various water saving measures and policies should be executes as soon as possible to promote the sustainable development.

Select this Article		The Federal Role in Water Supply Planning J. B. Connor, W. E. Cox, and V. K. Lohani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)323 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Drought is historically persistent and widespread in the United States and the federal government's role in addressing it is insufficient. According to the National Climatic Data Center, in any given year approximately 10% of the area of the United States experiences severe or extreme drought. It has also become increasingly problematic in the United States; not necessarily because of increased duration or magnitude, although these may be factors, but because of increasing demand. Over the last 50 years the amount of public water withdrawals has, on average, increased about 26% per decade. While the rate of withdrawal has slowed in recent years, it is still increasing at about 1% per year. It has been estimated that drought costs the United States approximately 6‐8 billion dollars yearly. Drought planning, management, and mitigation demands attention. Traditionally, the United States federal government's role in domestic, industrial, and agricultural water supply management is regulatory through programs such as the Clean Water Act and Endangered Species Act, and has tended to hamper planning. As the demand for, and shortage of, municipal water supply becomes more acute, the federal role has at best remained neutral and at worst become unfriendly to water supply planning. This lack of leadership has tended to exacerbate an increasingly critical situation.

Select this Article		Eco‐Efficiency Analysis of Existing Industrial Wastewater Treatment: How to Include the External Costs to the Environment L. Garcilaso, W. Gaines, and B. Barkdoll ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)324 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Many industries are required to treat their own wastewater before discharging to the environment directly or to a publicly‐owned treatment plant. It is of interest for them to quantify all costs involved to aid in planning and operation decisions. Costs of treatment chemicals are often the only costs regularly tabulated. The inclusion of all costs may be sometimes calculated, but it is rare that external environmental costs are included in decisions, principally due to cost considerations. Making an environmentally‐conscience decision, however, can actually increase profit if the product is advertised in such a way as to highlight its low environmental burden. Sales may increase if the potential buyers value the environment enough to alter their spending habits accordingly. Eco‐efficiency analysis is a tool used that allows the inclusion of not only internal life cycle costs, but also the cost to the environment, such as air and water pollution, energy used, and impact on humans and other living things. The method is demonstrated here on a typical wastewater treatment plant for an automobile manufacturer. The results show how the conversion from conventional treatment to ultrafiltration may reduce total treatment costs.

Select this Article		Water Conservation Techniques and Graywater Reuse at the Single Household Level R. Y. Alkhatib and J. Edgerly ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)325 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water has become a scarce resource on this earth. The population of the world is increasing tremendously while the earth's water resources are limited. Many efforts have been put forth to innovate water conservation measures. This work summarizes some analyses performed to investigate the effect and feasibility of applying different water conservation techniques in a US household with an emphasis on the use of graywater in both toilet flushing and landscape irrigation. Some outdoor and indoor conservation techniques are included such as xeriscaping, low‐flow toilets, and graywater reuse for toilet flushing and landscape irrigation. The analysis was performed on a house of 3 residents. Twelve conservation scenarios were run through a model developed using the STELLA software (Systems Thinking in an Experimental Learning Lab with Animation). The model outputs are the total amount of potable water used per year and the total amount of wastewater discharged per year. The model results were evaluated and compared based on a cost‐benefit analysis. Considering both the annual household savings and the payback period, the scenario which included all water conservation measures as well as graywater usage was the optimum. The optimum scenario achieved annual water savings of 93,000 gallons, which is about 50% of the annual water consumption in the base scenario. The graywater usage was responsible for about 35% of those water savings. The results of this study suggests that water conservation measures can be economically feasible in water scarce areas and stand to save homeowners a significant amount of money in the long run.

Select this Article		Assessment of Water Supply of Aurangabad City Bijlee Deshmukh and J. H. Godihal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)326 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this paper domestic water supply of Aurangabad city has been analysed in view of sustainability. Aurangabad is a city in Maharastra where domestic water supply need has been fulfilled by lifting water from a dam away from 50 km from city. This process is very costly as Rs10 per 1000 liters of water. So this practical case has been critically analysed in the paper and few sustainable solutions are provided.

back to top

COMPUTATIONAL TOOLS USED IN RIVER RESTORATION II

Select this Article		Application of a Depth‐Averaged 2‐D Model in River Restoration Weiming Wu and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)327 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A depth‐averaged 2‐D model has been developed for analyzing the impact of river restoration projects on flow, sediment transport, water quality, and ecology in aquatic systems. The hydrodynamic model solves the depth‐averaged 2‐D shallow water equations using the finite volume method on a non‐staggered, curvilinear grid. It uses SIMPLE(C) procedures with Rhie and Chow's momentum interpolation technique to handle the pressure‐velocity coupling. The model simulates the nonequilibrium transport of nonuniform total‐load sediment. The non‐cohesive sediment transport capacity is determined by one of four formulas that all account for the hiding and exposure effects among different size classes in bed material. The model is enhanced to consider the effect of helical flow motions on main flow and sediment transport in curved channels, local scour around bridge piers and spur‐dikes, effect of vegetation on fluvial processes, and cohesive sediment transport. The model also simulates heat transfer, pollutant transport and water quality in aquatic systems. The habitat suitability for various fish species is analyzed by using the simulated results of flow depth, velocity, temperature, dissolved oxygen, etc. The model has been well tested using experimental and filed data, and applied to help solve problems in river restoration projects.

Select this Article		CONCEPTS: A Process‐Based Computer Model of Instream and Riparian Processes Eddy J. Langendoen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)328 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Channelization and floodplain development have disturbed many stream systems throughout the US. Channels have responded through incision and planform adjustment, discharging large quantities of fine sediments that are a leading source of river and stream impairment. Many federal, state, and local organizations are active in restoring damaged channel systems. A particular challenge we face today is the lack of integrated, comprehensive modeling tools to evaluate the long‐term response of restored stream‐riparian corridors. The CONCEPTS computer model has been developed to evaluate stream‐corridor restoration designs. CONCEPTS simulates channel evolution by tracking bed changes and channel widening. It can predict the dynamic response of flow and sediment transport to instream structures. Recently, technology from the USDA‐ARS Riparian Ecosystem Management Model (REMM) has been integrated with CONCEPTS. The integration has resulted in a comprehensive stream‐riparian corridor model that can assess the effects of riparian buffer systems and forests on stream stability. Three studies using CONCEPTS are presented to demonstrate the capability of CONCEPTS to simulate channel morphology and response in diverse environments.

Select this Article		Design Tool for the Structural Stability of Rootwads in Streambanks Alan D. Wood ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)329 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This deign tool utilizes measurable and default characteristics of a rootwad, the streambank soil into which it is embedded, and the velocity of adjacent flows to estimate the ability of the rootwad to remain in place during design events. The stability is expressed in terms of factors of safety, for both a variety of the rootwad's individual components (e.g. header log, ballast rocks) and for the entire rootwad. The former allows the spreadsheet design tool to also be used to assess the stability of log vanes. Over 200 rootwads were installed as streambank stabilization projects at 17 sites, with a wide range of conditions, to verify the applicability of the model. The development of this tool was a joint project with USDA‐NRCS, PA‐DEP, and the Pennsylvania State University.

Select this Article		Stable Design Program for Meandering Channels Hui‐Ming Shih, Chester C. Watson, and Chih Ted Yang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)330 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Stable channel design is a major topic of stream restoration research. Since observed stream sediment transport rates are highly variable, channel design methods must examine a wide range of transport relationships to define stable conditions. The goal of this study is to present an improved method for stable design of meandering channels. This method uses both channel stability and equilibrium approaches. Channel stability is based on expanded consideration of the balance between sediment supply and transport capacity. Channel equilibrium is based on the minimum energy dissipation rate. The Stable and Equilibrium Channel Analysis Program (SE‐CAP) was developed to implement this new design method. SE‐CAP provides an improved version of the Copeland stability method that uses four different flow resistance equations and seven different sediment transport relationships. SE‐CAP provides additional tools to assess channel equilibrium for sand bed streams. Because it is based on a wider range factors, the SE‐CAP design method identifies conditions under which channel cross sections are stable and at equilibrium. SE‐CAP also provides tools for meander planform and longitudinal profile design. Case study results demonstrating an application of the SE‐CAP design procedure to the Bernalillo reach of the Rio Grande are presented.

back to top

ECOLOGICAL LINKS WITH SEDIMENT IMPAIRMENT FOR STREAM RESTORATION DESIGN

Select this Article		Geomorphic Meander Restoration of Incised and Aggraded Systems in the Blue Mountain Range in Washington State W. Barry Southerland ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)331 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The 325‐square mile Asotin Creek Watershed is located in the Blue Mountain Range in Washington State. Asotin Creek is one of several Model Salmon Recovery Watersheds designated by the Northwest Power Planning Council. In January 1997, two large floods caused extensive stream damage. The streamflow magnitude exceeded a 40‐year return period flood that was 10 times greater than the bankfull discharge. Prior to the flood, Asotin Creek was an unstable, high width/depth ratio channel caused by a long history of poor land use practices. Previously constructed dikes in some locations breached during the flood. Poor riparian vegetation and associated unstable banks caused the stream to convert from a single or dual‐thread channel to a multiple‐thread braided channel following the flood. The South Fork tributary to Asotin Creek had incised during the 1997 flood event. Both reaches contained potential steelhead habitat due to their proximity to the Snake River. Existing post‐flood habitat was degraded due to bank instability, high sediment supply, elevated water temperatures, poor spawning habitat and the lack of both overhead and in‐stream cover. During the summers of 1997 and 1998, two natural channel meander reconstructions were completed on the braided reach (Koch Project) and on the incised reach (J‐Bar Ranch), both in the same watershed. A geomorphic approach using a combination of dimensionless ratios, empirical relationships, and bedload competence equations related to a specific reference stream type were used as a basis for the designs. Since 1997 and 1998, each restoration project has been monitored for response. Both sites have been subjected to several floods exceeding five times the bankfull stage. Even though both streams are in high bedload watershed conditions, the restored reaches have not only maintained their stability, but also substantially improved the anadromous salmonid population, riparian vegetation, root cohesion, and floodplain development. In both cases, a stable plan‐form, dimension, and profile have been maintained since the restoration projects were completed. Local deposition and scour have been achieved with riparian cover and woody debris without aggradation or degradation. In‐stream structures were integrated as a component of the geomorphic design as opposed to pre‐selecting structures to stabilize the post‐flood channel. Reconstructing a stable channel dimension, pattern and profile following geomorphic processes met the multiple objectives of the restoration, yet accommodated subsequent large floods. The restoration monitoring provided evidence to document the success of the restoration.

Select this Article		Linking Benthic Macroinvertebrate Bioassessments to Channel Stability and Bed Sediment Characteristics Kelley Haerer Williams and John S. Schwartz, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)332 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract As watersheds are disturbed by human activities on the land and in the streams, hydrology and sediment budgets are modified so that channel morphological instabilities occur, promoting further changes in watershed sediment dynamics. Because channel morphology and physical habitat structure are interrelated, it can be assumed that unstable channel conditions cause unstable habitat conditions, thereby lowering biological integrity. Better watershed assessment tools are needed that link channel stability to physical habitat structure and biological integrity. This study's approach evaluates the utility of channel stability index, the Rapid Geomorphic Assessment (RGA) assessment protocol developed by the USDA National Sedimentation Laboratory to predict sediment impairment as indicated by bethnic macroinvertebrate indices of biological integrity (MIBI). In addition, this study evaluated different sediment size classes and their correlation to MIBI scores. In our study, 76 sites in Ecoregion 67, the Ridge and Valley EcoRegion of East Tennessee were examined for channel stability and bed sediment particle size distributions (PSDs) at stream sites with MIBI scores conducted by the Tennessee Department of Environment and Conservation. Bed sediment was collected in a unique field protocol to capture sediment transport “history”, and PSDs were conducted by standard ASTM methods. The analysis found a strong positive relationship between RPBIII scores and larger bed sediment material (gravel to cobble), and a negative relationships with fine sediment at approximately 0.016 mm (silt). Finer sediments < 0.016 mm such as clay did relate as well as the above stated relationships. This information is important for the development of sediment TMDLs, indicating that instream BMPs that create riffle habitat will be effective over some of the negative ecological stress imposed by fine sediments, primarily in the silt size range. Other than visually aesthetics, the clay fraction may not be as important ecologically as having gravel or larger bed sediments to create good habitat structure.

Select this Article		A Depth‐Averaged 2‐D Analysis of Fish Habitat Suitability Impacted by Vegetation and Sediment Zhiguo He, Weiming Wu, and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)333 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Two‐dimensional habitat modeling is becoming more and more necessary because the eco‐hydraulic information in longitudinal and lateral dimensions in rivers and wetlands is essential for habitat evaluation, especially in habitat restoration projects. A general habitat module based on the FVM‐based CCHE2D model has been developed to reproduce and quantify the complex characteristics of flow in a river reach for better assessment of habitat. The established model has been applied to study the effect of large wood structures on fish habitat in the Little Topashaw Creek and the effect of sediment transport on fish habitat in a reach in the Mississippi River. Generally, the change of bed topography due to the addition of large wood structures can redistribute the water depth and flow velocity, which influence the distribution of habitat area. The usable habitat area is underestimated if vegetation is not considered, while it may be overestimated if sediment transport is not considered.

Select this Article		Restoration of Wallens Bend and Clinch Rivers to Reduce Sediment near Threatened Mussel Shoals Michael F. Adams, Jr. and Greg Babbit ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)334 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Clinch River in Northeastern Tennessee supports some of the most diverse, and threatened, mussel shoals in the world. Sediment produced by agriculture, mining, and other anthropogenic activities upstream has endangered the stability of this fragile ecosystem. The Tennessee Stream Mitigation Program, in conjunction with The Nature Conservancy and the Tennessee Wildlife Resource Agency, identified two sites along the Clinch River and a tributary where suitable restoration practices could significantly decrease the amount of erosion and sediment entering the Clinch River system as a consequence of changes upstream of the mussel beds. One site consisted of a 450 foot section of actively eroding bank on the Clinch River. The other site was Wallens Bend, a 2,400 linear foot channelized tributary that is actively incising into the valley floor. This paper discusses the process of identifying potential restoration sites; conducting assessments to identify the existing condition of impacted streams; collecting and analyzing relevant geomorphic and sediment data; developing channel plan, dimension and profile geometry; selecting appropriate vegetation; and developing a construction plan. The project was designed utilizing a combination of empirical.and “analytical” methods. Dimensionless ratios derived from a reference condition provided the foundation on which the design was developed; however, before the design was finalized a series of analytical equations were utilized to assess the sediment transport characteristics of the stream. To minimize the intrusion of equipment into an environmentally sensitive area, the eroding bank along the Clinch River will be reconstructed to correct geometrical deficiencies and supplemented with in‐stream structures designed to relieve shear stress along the banks. Wallens Bend will be relocated in the historic valley bottom and the sinuosity will be greatly increased, adding approximately 2,000 linear feet to the channel. The objective of the project is a significant reduction in bank erosion at both sites and an increase of biodiversity within the channel bottom and riparian corridor.

back to top

HYDROLOGIC MODELING OF WETLANDS

Select this Article		Preliminary Analysis of Lake Pontchartrain Pollution after Hurricane Katrina Sinem G. Kilic and Mustafa M. Aral ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)335 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Lake Pontchartrain played a very important role for the damage control processes in New Orleans following Hurricane Katrina. After recharging flood waters back into the lake, the city was able to welcome its residents earlier than otherwise possible. However, this operation may yield Lake Pontchartrain to be a source of water pollution in years to come. In this paper, we examine the self‐cleaning capacity of Lake Pontchartrain after recharge of the flood waters into the lake. Since the chemical content's of the recharged flood water is not known, three contaminants are selected for this study as representative contaminants for their different physicochemical properties. The results show that for highly hydrophobic contaminants, dilution will not be a solution. For this case we estimate that the lake will require about 80 years recovering from the stresses created. A more volatile compound will disappear from the lake system in about a year. A pesticide will stay in the system in harmful quantities for about 13 years.

Select this Article		Rainfall‐Based Management Plan for Water Conservation Area 3A in the Florida Everglades Chandra S. Pathak and Samuel Palermo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)336 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The South Florida Water Management District (District) is responsible for managing water resources in a 46,439‐square‐kilometer (17,930‐square‐mile) region. The area prominently contains Lake Okeechobee, the second largest freshwater lake in the United States, and the internationally recognized Everglades wetlands. The Water Conservation Areas (WCAs), major components of the Everglades, supply water to Everglades National Park and the lower east coast of south Florida. They consist of WCA‐1, 2A, 2B, 3A, and 3B. WCA‐3A, the largest of the five WCAs, covers a 198,727 hectares (491,049 acres) wetland area and is situated immediately north of the Park. The WCA‐3A Rainfall‐Based Management Plan is used to operate water control structures that maintain desired water levels in WCA‐3A. The objective of the plan is to restore a more natural hydroperiod and hydropattern in Northeast Shark River Slough and Everglades National Park A model is being used to define flow targets for the operation of five water control structures (S‐333 and S‐12A, B, C, and D) along the southern boundary of WCA‐3A subject to upstream hydrologic conditions and downstream hydrologic and ecologic constraints. This paper details the mathematical model used to compute target weekly flow volumes to be released from WCA‐3A. The model uses weekly rainfall data from ten rain gauges, weekly evaporation data from three pan evaporation gauges, and weekly average stage data from three water level gauges. The performance of the model, i.e., computed flows, was evaluated from 2002–2005, when weekly rain gauge data were substituted by area‐weighted averages of weekly gauge‐adjusted NEXRAD (Next Generation Weather Radar) rainfall data. The average weekly rain gauge data were also compared with weekly gauge‐adjusted NEXRAD data for the same four‐year period.

Select this Article		Hydrologic Analysis for a Floodplain Forest Wetland Mitigation Site B. Michaud and J. Gumtow ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)337 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Fournier floodplain forest mitigation site is a 5‐acre wetland design north of Stevens Point, Wisconsin, located within the 100‐year floodplain of the Wisconsin River. The surface water level on the site is regulated by a dam downstream. The floodplain forest mitigation site was created by grading the ground surface down to a more frequent flood elevation and then planting the site with the appropriate floodplain forest trees and shrubs. Critical to the success of the mitigation is grading the appropriate ground elevation. While some surface flooding is necessary, research indicates it is not desirable to have prolonged flooding over restored floodplain forests because of reduced tree seedling and sapling survival rates. Surveyed land surface and water elevations, groundwater elevations, river flow data and hydraulic modeling analysis were used to analyze the wetland hydroperiod for the site. A hydraulic computer model, HEC‐RAS, was used to calculate water surface elevations for a range of flow rates. HEC‐RAS was used to model both steady state (constant flow rate) and unsteady state (varying flow rate over time) conditions. The calculated water surface elevations from the steady state and unsteady state models have over a foot of difference at flood flow rates. Initially it was thought that the unsteady state model would more accurately depict actual stage conditions because flow in actual conditions does vary over time. However, the steady state model results are more consistent with the available measured data. The hydroperiods developed from both the steady state and unsteady state model results were used to determine a grading elevation that floods annually but not flooded for such long periods of time as to inhibit tree sapling survivability. The selected grading elevation met this criteria according to the hydroperiods developed from both models. Measured water surface levels from the spring flood of 2006 will be compared to the model data to further verify the modeling results.

back to top

MONITORING, ASSESSMENT, AND POLICY ISSUES IN RIVER RESTORATION

Select this Article		Urban Stream Restoration: Guidance for Monitoring and Assessment Protocols John S. Schwartz, P.E., Sue L. Niezgoda, Louise O. Slate, P.E., Robert Prager, P.E., Donald D. Carpenter, P.E., Munsell McPhillips, and Shannon Lucas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)338 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper is a joint product of the Urban Stream Restoration Task Committee (TC), a TC of the River Restoration Committee of the Hydraulics and Waterways Council (HWC), and the Urban Streams Committee of the Urban Water Resources Research Council (UWRRC). The goal of this endeavor is to produce a guidance document for monitoring and assessment protocols of urban stream restoration projects. Several stream restoration guidance documents contain sections with general protocols that do not distinguish their applicability between conditions found in urban and rural streams. General protocols typically rely on a reference stream to complete a pre‐design assessment and a post‐project comparison. Our product will differ from existing guidance documents because this effort focuses on urbanizing and urban streams, in which reference streams rarely exist and the return to a pristine (pre‐development) condition through restoration is highly unlikely. Our final document will include a comprehensive summary of monitoring and assessment techniques used by the many disciplines (e.g., fluvial geomorphology, geotechnical and hydraulic engineering, ecology, etc.), integrated into a set of guidance protocols that do not necessitate the need for a reference stream. Motivation for this effort is the outcome of past meetings of the River Restoration Committee and Urban Streams Committee, in which members have identified its need among practitioners. This paper summarizes the progress to date, and provides an outline of the proposed guidance manual sections.

Select this Article		Hydrologic Monitoring Criteria for Freshwater Wetland Plant and Animal Communities Michael Duever and Ananta Nath ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)339 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Wetland hydrologic studies often occur because of concern for a wetland's plant and animal communities, which are controlled by relatively small fluctuations in water levels on these generally low relief landscapes. Hydrologic monitoring is typically designed to address two primary questions. What are the natural hydrologic processes operating at a site? How have they been altered by human activities? We address these questions primarily by installing monitoring wells on transects to document water table fluctuations above and below the ground surface. These transects are established along the primary hydrologic gradients resulting from natural processes on the site as well as those resulting from human alterations on and around the site. Wells along the transects are installed in multiple examples of each of the major plant communities to document the relative degree of human influence within each major type of plant community and in different parts of the site. In areas with a high groundwater table, the wells are normally open between about 6 and 12 ft below the ground surface to document the relationship of the water table to the site's vegetative characteristics. They are typically hand‐driven because of the inaccessibility of most of our monitoring sites. Since they are driven into the ground and we are usually working in environments that burn frequently, we use galvanized steel pipe. Most of the monitoring has been done periodically (weekly‐to‐monthly) by hand because of limited funds and the remoteness of the well locations, although we try to have a few continuous water level recorders located somewhere on or near our study sites. We plan on a minimum of three years monitoring, and are usually able to extend this period of record by developing correlations with other nearby hydrologic or climatologic stations. Since the longer the period of record, the more valuable the data becomes, we try to initiate some level of hydrologic monitoring as soon as possible, particularly on sites where we have long term management responsibilities.

Select this Article		Regulatory Issues in Stream Restoration Karen C. Kabbes, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)340 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract When an team designs a stream restoration project, the design team is also responsible for the submission of associated permits. Permits and other reviews may be required by a number of Federal, state and local agencies for the same project. Some permit and review criteria may not be sympathetic and, at times, seem contradictory to the restoration project's design intent. For example, designing a dam removal and channel restoration project that does not immediately stabilize channel banks with vegetation or rock may appear to be in conflict with some of the soil erosion and sediment control practices or other water quality requirements. Designing and permitting a restoration project may then require the designer to take on a significant education role with regulators. Using local professional organizations or key regulators to help arrange educational seminars by leading restoration practitioners is one method of helping assure project reviewers understand some of the necessary principles to authorize a successful project.

back to top

PRACTICING PROFESSIONAL ETHICS IN RIVER RESTORATION

Select this Article		The Implications of Academic Dishonesty in Undergraduate Engineering on Professional Ethical Behavior D. D. Carpenter, T. S. Harding, and C. J. Finelli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)341 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Student academic dishonesty, commonly referred to as cheating, has become a serious problem at institutions of higher education. This is particularly true of engineering students who, according to previous research, are among the most likely to cheat in college. In addition, research on college students in all fields has indicated that such behavior is more common among students who participate in academic dishonesty at the high school level and that it is correlated with other deviant or unethical behaviors, such as petty theft and lying. If, in fact, such correlations do exist, one might hypothesize that there is also a relationship between academic dishonesty in college and deviant or unethical behavior in professional practice. Placing this relationship in the context of higher levels of academic dishonesty among engineering students only increases the seriousness of the problem for engineering educators, professionals, corporations, and society. To investigate this concern, the authors have undertaken two research projects. The first project focused on the Perceptions and Attitudes toward Cheating among Engineering Students (PACES‐1). The goal of the research was to develop a better understanding of what students and faculty perceive as cheating and to use this knowledge to help instructors and institutions increase the level of academic integrity. The second project examined the correlation between academic dishonesty and unethical behavior with a majority of the students in the sample having worked for a considerable period of time during their college years. This provided a unique opportunity to study the connection between academic dishonesty and professional behavior within the same sample of individuals. This paper will discuss some of the implications of academic dishonesty on professional ethical behavior and provide an overview of the two investigations conducted by the authors.

Select this Article		Ethics in River and Stream Restoration: Biomimicry or Charade? Robert Prager, P.E. and Munsell McPhillips, Ph. D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)342 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper will explore ethical issues facing designers offering services in river and stream restoration. The concept of biomimicry, or the effort to emulate natural processes in our designs has received intense interest in fields ranging from wastewater treatment to building design tc medicine. It is certainly true that over millions of years, nature has evolved sophisticated and elegant solutions to a host of challenges that those working in the built environment could and should study. There are several forms of mimicry currently at play in river and stream design. Some are based on direct emulation of channel form while others seek to mimic the many energy management strategies that streams use to achieve dynamic equilibrium. Recently our profession and allied disciplines have engaged in spirited discussion about form‐based versus process‐based design and the reported high failure rate of stream restoration projects. Maybe a more important discussion should address the completeness of mimicry in the failed projects. Is either of the two methods adequately performed in the different design approaches? It is likely that both approaches are valid in certain design circumstances; however, both are prone to failure if the mimicry is superficial. In discussions with private sector colleagues, it becomes increasingly clear that we operate in a business climate that accommodates and even encourages designers with very limited understanding of both stream mechanics and ecology. The training of too many designers is limited to a workshop that lasted from half a day to one week. In our experience it is common for designers little or no training in life or earth sciences to attempt restorations. These designers fall into two general groups, those that don't know what they don't know and those that don't care because the “stream restoration” marketplace is ripe for the picking. In this case, the design is not one of true mimicry but little more than an over‐simplified charade. Our profession is now grappling with solutions. In this paper we will discuss the many options available including efforts to better educate designers, regulators and project owners. We could consider promoting more restrictive design requirements, design manuals and methods of practice. Still others are advocating a specialty registration for fluvial geomorphic engineers analogous to that for structural engineers and in some states, geotechnical engineers. Regardless of the specific path our allied professions choose, it is vital that we find a way to resolve the problem of designers working outside their expertise.

back to top

RIVER RESTORATION DESIGN METHODOLOGY I

Select this Article		The Application of Stream Classification Using the Fluvial Geomorphology Approach for Natural Channel Design: The Rest of the Story David L. Rosgen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)343 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The geomorphic approach for Natural Channel Design (NCD) using stream classification has been applied in river restoration projects by the author for nearly four decades. Lessons learned during this period have led to significant modifications and improvements in the method. The current procedure has evolved as scientific principles have been applied in field practice. These methods have been successfully implemented and monitored for large‐scale restoration projects. This method, however, has drawn criticism from individuals in the scientific community. This paper addresses specific issues raised in an attempt to clarify the proper use of the methodology. The following topics related to natural channel design are reviewed: (1) Proper determination of bankfull discharge, (2) Process‐based versus form‐based approaches to stream restoration, (3) Field data collection and its relation to temporal and spatial variability, (4) The applicability of particle size analysis, and (5) Stream classification and population variance.

Select this Article		The Natural Channel Design Method for River Restoration David L. Rosgen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)344 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Research and restoration implementation of nearly four decades has resulted in the development of the principles and procedural sequences of natural channel design. The procedure includes the implementation of fluvial geomorphology relations to assist in stability assessments, as well as the application of sedimentological, hydraulic and morphological relations. Procedures for natural channel design include analog, empirical, and analytical methods. The proper implementation of this approach requires fundamental training and experience using this Fluvial Geomorphology method. Experience and formal training in geomorphology, hydrology and engineering is required to implement this method. The restoration specialists must also have the ability to integrate principles from multiple disciplines, such as fishery biology and plant science, and most importantly, they must be able to implement the design in the field. Sediment competence and capacity computations are key parts of the assessment and design phases. The methodology is broken into eight major sequential phases (1) Define specific restoration objectives associated with physical, biological and/or chemical process, (2) Develop regional and localized specific information on geomorphologic characterization, hydrology and hydraulics, (3) Conduct a watershed/river assessment to determine river potential, current state and the nature, magnitude, direction, duration and consequences of change. Obtain concurrent biological data (limiting factor analysis) on a parallel track with the physical data, (4) Consider passive restoration recommendations based on land use change, in lieu of mechanical restoration. If passive methods are reasonable to meet objectives, skip to the monitoring phase (8). If passive efforts and/or recovery potential do not meet stated multiple objectives, then proceed with the following phases, (5) Initiate natural channel design with subsequent analytical testing of hydraulic and sediment transport (competence and capacity) relationship, (6) Select and design stabilization/enhancement/vegetative establishment measures and materials to maintain dimension, pattern and profile to meet stated objectives, (7) Implement the proposed design and stabilization measures involving layout, water quality control and construction staging; and (8) Design a plan for effectiveness, validation and implementation monitoring to ensure stated objectives are met, prediction methods are appropriate and the construction is implemented as designed. Finally, design and implement a maintenance plan.

Select this Article		A Deterministic Bank‐Stability and Toe‐Erosion Model for Stream Restoration Andrew Simon and Eddy J. Langendoen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)345 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sediment is one of the principle pollutants of surface waters of the United States and sediment eroded from streambank failures has been found to be the single largest contributor to suspended‐sediment loads to streams draining unstable systems in the mid‐continent. With the recent focus on stream restoration, a quantitative means was needed to predict critical conditions for stability and the effects of riparian vegetation on attaining stable bank geometries. A deterministic bank‐stability model was developed in the late 1990's at the USDA‐ARS National Sedimentation Laboratory and has undergone substantial enhancements since that time. The original model allowed for 5 unique layers, accounted for pore‐water pressures on both the saturated and unsaturated parts of the failure plane, and the confining pressure from streamflow. The enhanced Bank Stability and Toe Erosion Model (Version 4.1) includes a sub‐model to predict bank‐toe erosion and undercutting by hydraulic shear. This is based on an excess shear‐stress approach that is linked to the geotechnical algorithms. Complex geometries resulting from simulated bank‐toe are used as the new input geometry for the geotechnical part of the bank‐stability model. The enhanced bank‐stability submodel allows the user to select between cantilever and planar failure modes. In addition, the mechanical effects of riparian vegetation are included.

Select this Article		Flow Energy, Time, and Evolution of Dynamic Fluvial Systems: Implications for Stabilization and Restoration of Unstable Systems Andrew Simon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)346 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Alluvial streams are open systems which dynamically adjust to variations in flow energy and sediment supply. This balance can be referred to as dynamic equilibrium and implies that alluvial streams adjust their morphology in a variety of ways as a function of the imbalance between available force and upstream sediment delivery, and boundary resistance to hydraulic and geotechnical forces. Thus, two channels of similar morphology disturbed by an identical perturbation can attain very different equilibrium morphologies. Similarly, diverse alluvial systems disturbed by different perturbations can adjust in a similar manner manifest in cross section or reach morphologies. Both of these scenarios, although apparently divergent, can be explained in terms of non‐linear reductions of stream power and flow energy with time and associated resistance of the boundary materials to streambed erosion by hydraulic forces and channel widening by mass failures. The common thread provided by analysis of flow energy is applicable in stream restoration practice because the physics of flow energy, sediment transport and mass failure do not vary by stream type or by region. Research into how disturbed fluvial systems respond to large perturbations was conducted using field‐based analyses and numerical modeling of channel processes. Time‐series cross sections from the Toutle River System over a 10‐year period following the 1980 eruptions of Mount St. Helens and a 20‐year period for alluvial streams of West Tennessee following channelization were analyzed in the context of adjustments in stream power and flow energy. Numerical simulations of sand‐bed channels with banks of varying cohesive strengths and disturbed by cutting off half of the upstream sediment supply showed diverse morphologic adjustment that could be explained by boundary resistance and non‐linear reductions in flow energy with time. Results provide a unifying means to understand how similar disturbances result in different morphologies and how different disturbances can result in similar morphologies. These are central issues in channel response and consequently, to design of stream restoration projects, particularly for those practitioners operating from a form‐based perspective.

back to top

RIVER RESTORATION DESIGN METHODOLOGY II

Select this Article		A Method to Select Surface Bed Samples that Represent Bankfull Conditions in Active Gravel Channels Alan Schlindwein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)347 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sediment transport modeling of natural channels should be performed using surface samples that represent the flow conditions of the desired design flow. The most common flow used in natural channel design is the bankfull flow, also know as channel forming flow. However selecting a surface sample that adequately represents this flow condition is a daunting task. This paper presents a method for analyzing surface and subsurface sediment samples to determine the flow condition that occurred when the channel bed surface was created. This method was used in the design of a sand‐gravel channel built in Indianapolis, Indiana and was originally discussed in a presentation at the 2004 EWRI World Water Congress in Salt Lake City. This paper documents the method and proposes the conditions when this method may be applied.

Select this Article		Natural Channel Design Difficulties When Confronted with Anthropogenic Downstream Fining in a Sand‐Pebble Channel Alan Schlindwein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)348 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Natural downstream fining of gravel channels to sand channels occurs by several mechanisms in many rivers and streams. This condition presents several extreme difficulties when natural channel design is proposed in a reach where this fining occurs. However, when this fining occurs by man‐induced changes in a stream channel, there are no clear methods for accounting for such artificial boundary conditions. This paper discusses the use of at‐a‐station hydraulic geometry analysis in a sand‐pebble channel for used in a remediation design at Pope Air Force Base in North Carolina. The failure of the original natural channel design at this location was discussed in a paper presented at the 2004 EWRI World Water Congress in Salt Lake City. The proposed remediation sand bed channel design will be discussed in this paper.

Select this Article		Spreadsheet Tools for River Evaluation, Assessment and Monitoring: The STREAM Diagnostic Modules G. E. Powell, D. E. Mecklenburg, and A. D. Ward ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)349 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Stream physical condition is increasingly a priority for resource managers. Assessment, monitoring and restoration techniques continue to be developed and standardized. A suite of spreadsheet tools, the STREAM Modules, has been developed by the Ohio Department of Natural Resources and Ohio State University to meet the technical demand. This ongoing project began in 1998 and includes the following modules that are available at no cost: (1) Reference Reach Spreadsheet for reducing channel survey data and calculating basic bankfull hydraulic characteristics, (2) Regime Equations for determining the dimensions of typical channel form, (3) Meander Pattern that dimensions a simple arc and line best fit of the sine‐generated curve, (4) Two‐Stage Geometry that sizes a two‐stage channel system based on regional curves and provides estimates of earthwork requirements to construct various two‐stage geometries, (5) Sediment Equations which includes expanded and condensed forms of critical dimensionless shear, boundary roughness and common bed load equations, (6) Effective Discharge that, based on historic data from USGS stream gages, develops a Wolman‐Miller geomorphic work plot and contains several methods for calculating the geomorphic work and the effective discharge, (7) Lane Balance educational tool, and (8) Contrasting Channels that computes hydraulic and bed load characteristics in a side‐by‐side comparison of two channels of different user defined forms. An overview of each module will be presented together with example applications.

Select this Article		Channel Restoration Design of Deadman's Run Tributary: An Application of Tractive Shear Analysis and Regime Methodology Brian Kwiatkowski, Robert Prager, P.E., and Mark Meyer, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)350 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Deadman's Run Tributary, located in Lincoln, Nebraska, was channelized and has since been subjected to more than forty years of extensive repairs using conventional hard armor methods. These methods have been largely ineffective at addressing the underlying cause of widespread bank erosion: channel incision. The existing channel bed slope is more than an order of magnitude higher than what is customary for undisturbed regional streams. It is anticipated that, if left to its own devices, the tributary channel would continue to erode and eventually re‐construct a sinuous channel inside an entrenched floodplain. To address the severe erosion problems along the tributary, project stakeholders including the City of Lincoln, The Lower Platte South Natural Resource District and the University of Nebraska, Lincoln, retained the design team of The Schemmer Associates, Inc. and Intuition & Logic to provide analysis and channel restoration design. Our objective was to restore dynamic equilibrium to the tributary based on the current hydrologic regime and restore a stable meandering planform. Design requirements included a low‐flow channel that would accommodate the stream‐forming flow and a flood channel capable of conveying the 1‐percent recurrence flow. An additional challenge to the design was the close proximity of the upper tributary reach to University research orchards. Recent publications provide a number of design methodologies for channel restoration. This paper presents a method used for the restoration design of Deadman's Run Tributary; a combined approach of tractive shear analysis and regime methodology, based on the planform geometry equations from Soar et al. To avoid a uniform planform appearance, a range of acceptable planform geometries was developed by varying channel sinuosity using the Meander Pattern 4.1 STREAM module, developed by the Ohio Department of Natural Resources and Ohio State University. The resulting variability in meander length, amplitude, and radius of curvature introduced an organic component to the design and, thus, more closely approximated the aesthetic of a natural meandering stream.

back to top

RIVER RESTORATION DESIGN METHODOLOGY III

Select this Article		Estimating a Stream Restoration Design Discharge Tyrel S. West and Sue L. Niezgoda ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)351 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A primary assumption of the natural channel design method for stream restoration is that the bankfull design discharge is the dominant discharge. Dominant discharge is defined as the theoretical discharge that if constantly maintained in an alluvial stream over a period of time will produce the same channel geometry that is produced by the long‐term hydrograph. The dominant discharge appears typically in two forms, the effective discharge and the bankfull discharge. The bankfull discharge is the most commonly used form in stream restoration projects. The selection of an appropriate design discharge that best approximates the dominant discharge is critical to the natural channel design methodology and will dictate the success of restoration projects in improving channel stability and water quality. In this paper, we present several existing methods of estimating dominant discharge, including methodology, assumptions, limitations, and appropriate applications. The goal of this paper is to offer the stream restoration community an introduction to dominant discharge and provide a reference that will aid in the selection of an appropriate design discharge for restoration projects.

Select this Article		Prediction of Flow and Bank Erosion in the Sacramento River Ali Ercan and Bassam A. Younis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)352 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Results of two‐dimensional (depth averaged) and three dimensional computations of a 1750m reach of the Sacramento River are compared with velocity data obtained in a large‐scale, distorted physical model of the same reach. The aim was to predict the level of modeling required to predict the occurrence of bank erosion observed in the field. Further results are presented which show the outcome of deploying 5 groins to inhibit bank erosion upstream of a bridge abutment. The simulations are also compared with experimental data to assess the performance of alternative shear formulae. Truncation errors are estimated using two alternative techniques. The results suggest that the occurrence and mitigation of bank erosion in large natural river systems can be predicted to an acceptable degree of accuracy.

Select this Article		The GeoTools Shareware Package for Fluvial Systems Analysis M. C. Brown, B. P. Bledsoe, and D. A. Raff ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)353 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An important contribution that engineers and geomorphologists can make to the practice of river restoration is to develop tools that increase the ability of practitioners to analyze complex stable channel design problems. This paper introduces GeoTools, a suite of analysis tools for fluvial systems written in Visual Basic for Applications/Excel. Based on a time flow series and basic input data, GeoTools provides users with outputs including effective discharge and sediment yield calculations, temporal distributions of hydraulic parameters (e.g. shear stress, specific stream power, and scour indices), channel stability indices and over 80 hydrologic metrics, hi combination, these modules allow users to quickly compute metrics related to stream channel form, impacts of climate and land use changes, and flow alteration. A case study is detailed to illustrate the benefit of applying GeoTools to a channel restoration project.

Select this Article		An Overview of a Two Dimensional Hydraulic Modeling of Llano Seco Riparian Sanctuary on Sacramento River Su Mishra, Ph.D., P.E., Morgan Vaughn, P.E., and Tom Smith, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)354 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Llano Seco riparian sanctuary is located near River Mile (RM) 177 of the Sacramento River, on the eastern floodplain of the river. This particular section of the Sacramento River has a natural overflow which discharges into the Butte Basin to the southeast. The flood control levee on the east side of the river begins near the downstream end of the model (approximately at RM 176). The floodplain on the west bank of the river in the project reach is controlled by a levee, which begins upstream at approximate RM 184. The restoration area is located adjacent to the river, on the east side, between RM 177 and RM 178. In previous years riparian growth was on the majority of this area, documented in the historic 1952 and 1974 aerial images. The riparian growth was almost entirely removed (except a small section adjacent to the river at the top of the bend) at some time after 1974. It has been proposed to convert approximately 350 acres of grassland/savannah to riparian habitat. A two‐dimensional (2D) hydraulic model of the Sacramento River, from River Mile (RM) 173 to RM 194 was developed and run to assist in this analysis. The resulting water surface elevations were compared to the design water surface elevations developed by the US Army Corps of Engineers (USACE) in 1957 for the Sacramento River Flood Control System.

back to top

STREAM ECOLOGY AND RIVER RESTORATION

Select this Article		Temporal Variation of Dissolved Oxygen in a Mountain Stream Plunge Pool: An Example from Northen Turkey S. Kucukali, S. Cokgor, and B. Kartal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)355 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, a forested‐mountain stream (Harmankaya) with a drainage basin about 12 km² located in Zonguldak (41°N‐31°E) on the NW of Turkey has been studied associated with its plunge pools during April and November 2004. In the stream, 22 plunge pools were detected and plunge pools drop heights had a variation of 0.7–20 m, whereas average pool depths had a range of 0.53–1.59 m. In a selected pool, the variation of dissolved oxygen (DO) concentration and temperature (T_w) through the pool depth have been investigated at different time intervals. The data indicated the seasonal dependence of dissolved oxygen concentration in the plunge pool related with the water temperature and when the pool exposed to sunlight thermal stratification occurred through the pool depth. Besides, in all seasons DO levels had a downward trend from pool surface to pool bottom. Riparian vegetation significance has been emphasized in terms of the regulating the temperature and dissolved oxygen levels of a pool especially during the summer. Moreover, pool well‐shaded site had relatively low degree of thermal stratification compared to waterfall impact site because of the canopy cover.

Select this Article		Treatment of Urban Runoff Using Constructed Wetlands in New Delhi, India Atul K. Mittal, Mehul Jain, Priyanka Jamwal, and J. M. Mouchel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)356 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The River Yamuna forms an integral part of the Indo‐Gangetic plains. Delhi, capital of India, constitutes only 2% of the entire catchment area of the River Yamuna. The pollution problem posed by urban wastewater discharges from open storm drains owes its origins to the inadequate development of sewerage systems in the city, coupled with sharp increases in population stemming from the industrial revolution. Early approaches to mitigate pollution load in river under Yamuna Action Plan (YAP) were focused on the treatment of domestic as well as industrial wastewater, whereas the issue of urban runoff remained completely untouched. The present research is directed at the development of constructed wetlands, in order to achieve an optimal solution to the requirement to treat sewage (treated as well as untreated) and urban runoff whilst meeting environmental requirements of the receiving water. The availability of land was a problem on the banks where the drain meets the river; hence a methodology is proposed to transfer the drain water by means of aqueducts to the opposite bank, where there is availability of unused floodplains of the river. For the entire treatment setup it is found that even though initial investment required is huge but the running and maintenance cost is very low as compared to conventional sewage treatment plants. It is concluded that if implemented correctly these wetlands would not only provide an ideal solution to help curb the problem of pollution but also create a healthy natural ecosystem near the riverbanks.

Select this Article		Environmental Restoration of the Xinzhou River in Shenzhen Jian Liu, Ph.D., M. ASCE, Minghua Huang, Peng Lou, and Wen Xiao, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)357 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Xinzhou River, a naturally meandering stream, was reformed into a man‐made canal in 1989. The discharge capacity of the river was improved after canalization and the flood control standard was elevated. At the same time, the adverse effect on ecosystem of the river basin emerged. The environmental pollution of the whole Xinzhou River is serious at present, and the polluted situation is especially worse in the tidal reach. The water quality of the Xinzhou River is lower than Class V of the surface water stipulated in Chinese national Standard. The studies and experiments were carried out for the environmental restoration of the Xinzhou River and some river restoration projects for the whole river were launched in 2004. The different improved methods were put forth in the upper, middle and lower reaches. The ecological restoration technologies such as clearance of the polluted deposit, supplement of clean water, ecological gravel bed, aeration technology, ecological bank revetment, and bed slab are employed in the different reaches according to geography and water quality conditions. Some suggestions are presented on the basis of the field investigation results.

Select this Article		Underwood Creek Rehabilitation and Flood Management, Menomonee River Watercourse, Milwaukee, Wisconsin Thomas R. Sear, P.E. and David C. Fowler ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)358 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Underwood Creek is a major tributary of the Menomonee River, extending approximately eight miles from its confluence with the Menomonee River, near Milwaukee County Grounds (MCG), to its headwaters in Waukesha County. The Underwood Creek Watershed is approximately 84 percent developed with a variety of urban land uses. Given this high degree of urbanization and the need to address local flood management concerns, Underwood Creek underwent considerable alteration in the mid‐1960's, including channel widening and realignment, and the installation of concrete lining along a significant portion of its length. These channel alterations have resulted in increased peak discharges and channel velocities during periods of intense rainfall that successfully reduced peak water surface elevations along Underwood Creek, but contributed to flooding conditions along portions of the Menomonee River located downstream. As a result, the Milwaukee Metropolitan Sewerage District (MMSD) has initiated the design and installation of an approximately 1.2 million cubic meter (900 acre‐feet) floodwater storage facility on MCG property that will receive excess floodwaters from Underwood Creek. Reduced peak discharges on Underwood Creek provide an opportunity to rehabilitate about 2 kilometers (6,600 feet) of this watercourse through removal of the concrete channel lining, and the development of a meandering bioengineered channel, with riffle and pool sequences. The adjacent floodplain will also be lowered and vegetated to promote the development of wetland areas and riparian habitat. The Underwood Creek Rehabilitation and Flood Management Project is a unique opportunity for MMSD to achieve multiple benefits from the rehabilitated channel and floodplain that include desirable aesthetic, habitat and public safety improvements, while providing appropriate management of the one percent probability (100‐year) flood event. Preliminary engineering has been completed. Construction is currently scheduled for 2008 through 2010.

back to top

VEGETATION AND BANK STABILIZATION

Select this Article		Regional Application of Stream Classification Systems in Planning and Design of Streambank Stabilization Projects Frank Reckendorf and Lyle Steffen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)359 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In the author's regional fluvial geomorphology responsibilities at the National Technical Centers (NTC) of the Natural Resources Conservation Service (NRCS), and as consultants in retirement, they have done numerous geomorphic evaluations on hundreds of miles of streams across the United States. They typically applied three different stream classification systems: (1) Rosgen, (2) Simon or Schumm, Harvey, and Watson Channel Evolution Models (CEM), and (3) Montgomery and Buffington (Stream Planform Types). They have been using the Rosgen stream classification system for 19 years and have applied it in 22 different states. All three systems have been found to be robust at the stream reach level. The authors have taught these systems to hundreds of participants in applied fluvial geomorphology training sessions. Participants were able to take appropriate measurements or make observations to identify stream types. Plots of bankfull width and depth versus drainage area were drafted at most training locations to demonstrate the application of regional curves. One advantage of the Rosgen classification system is that users collect the data needed to make planning and design decisions for streambank stabilization projects. The Rosgen stream classification system, in combination with CEM, can be used to identify stream processes, predict trends in channel stability, and suggest bank treatment strategies. In summary, the Rosgen, CEM, and Montgomery and Buffington stream classifications can be applied to streams across the United States. The data collected and the resulting classifications help planners make sound decisions for streambank stabilization projects.

Select this Article		The Role of Riparian Roots in Resisting the Hydraulic Scour of Streambanks N. Pollen and A. Simon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)360 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Riparian vegetation interacts in a number of ways with the geotechnical and hydraulic processes operating in streambanks. Previous research has shown that roots provide mechanical reinforcement to soil through the production of root‐soil matrix, in which the roots resist tensile forces and strengthen banks against mass failure. In addition, plants have been shown to reduce pore‐water pressures, and thus increase the stability of streambanks through removal of water by evapotranspiration. However, to date, very little has been documented about the effect of roots on hydraulic scour at bank toes, which when eroded, greatly increase bank instability. Quantification of the effects of riparian vegetation on streambank stability is important if we are to be able to design channel restoration projects that use biological strategies based on geomorphic effects as well as ecological and aesthetic benefits. In this study a vertical jet‐test device was used to measure rates and volumes of scour in soils permeated by switchgrass roots. Twenty tests were carried out over a range of root densities. Root volume per unit volume of soil for the jet tests ranged from 0.0132 to 0.172 cm³_roots/cm³_soil. Erosion rates calculated for each jet‐test showed stepped profiles for tests with roots (compared to smooth profiles for non root‐permeated soils) because the roots protected the soil from erosion, initially at the surface and then at other points in the scour hole where roots were concentrated. Results show that the volume of soil scoured during a test declined non‐linearly with increasing root volume, per unit volume of soil, and with increasing root length density (RLD) and increasing root biomass. The r² for these relationships is fairly high despite the fact that root distributions relative to the shear stress field induced by the jet varied between tests, even under similar root volumes. The shape of the non‐linearly declining functions between scoured soil volume and root biomass/root length density/root volume, suggest that a threshold exists at a relatively low root volume or biomass, above which, scour‐hole volume was very small.

Select this Article		Temporal and Spatial Variability in the Root‐Reinforcement of Streambanks: Incorporating Variations in Soil Shear Strength and Soil Moisture into the RipRoot Model N. Pollen and A. Simon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)361 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The root‐reinforcement of soils strongly affects bank stability, and the resulting delivery of sediment to channels. Estimates of root‐reinforcement of soils have commonly been attained using perpendicular root models that simply sum root tensile strengths as a single add‐on factor to soil strength. A major limitation of such perpendicular models is that the effect of variations in soil moisture and bank geotechnical properties on root‐reinforcement are omitted. In reality, during mass failure of a streambank, some roots break, and some roots are pulled out of the soil intact; the relative proportions of roots that break or pull out are determined by soil moisture and shear strength, and root strengths. In this paper an equation to predict the frictional resistance of root‐soil bonds was tested against field data collected at Long Creek, MS, under two soil moisture conditions. The root pullout equations were then added to the root‐reinforcement model, RipRoot, and bank stability model runs for Goodwin Creek, MS, to examine the effects of spatial and temporal variations in soil shear strength and rooting density, on streambank factor of safety. Model results and field data showed that at low root diameters breaking forces exceeded pullout forces, but at higher root diameters pullout forces exceed breaking forces. The threshold diameter between root pullout and root breaking varied with soil shear strength, with increasing soil shear strength leading to a greater proportion of roots failing by breaking instead of pullout. Root breaking is the predominant mode of root‐failure in dry soils, or those with higher shear strengths, whereas pullout of roots is more common in soils that are moist, or have lower shear strength. Resulting Factor of Safety (F_S) values for the bank during the period modeled ranged from 1.36 to 1.74 with 1000 grass roots/m², compared to a range of 0.97 to 1.37 for the non‐vegetated bank. Root reinforcement was shown to increase bank stability over the entire range of soil moisture conditions modeled. However, the magnitude of root reinforcement varied in both space and time as determined by soil geotechnical properties and soil moisture.

back to top

CASE EXAMPLES IN SUSTAINABLE DEVELOPMENT

Select this Article		Experimental Study of HDPE Material Used for Pervious Pavement Components Qiaoqiao Bao, John W. Davies, Alan P. Newman, and Tim Davis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)362 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Pervious pavements are surfaces construction which allow rainwater to infiltrate the surface and into the underlying construction layers. They are an important option used for stormwater source control in Sustainable Drainage Systems (SUDS) and have received much attention from researchers, particularly with respect to their use as car parking surfaces. They also remove low levels of pollution from the water by filtration and also by biodegradation of hydrocarbons, which are adsorbed to materials within the construction. When higher exposures of oil are experienced these traditional structures can fail dramatically. The way around this is to incorporate an oil interceptor system into the pavement. The long term retention of large amounts of oil leads to further worries as to chemical and microbiological stability of the components which make up the structure, particularly when the materials used are plastics such as HDPE and polypropylene. The overall aim of this experimental study is to investigate the difference of tensile strength of HDPE in two different conditions: exposed in air and soaked in used engine oil and thus try to find out possible deterioration in performance of key components in pervious pavement systems.

Select this Article		An Overview of Graywater Collection and Treatment Systems R. Y. Alkhatib, L. A. Roesner, and C. Marjoram ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)363 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The use of graywater is becoming more and more common, especially in areas where water resources are scarce. A wide range of graywater systems exists; from simple collection to complex collection/treatment. Currently, the market recognized this trend and need for using graywater. So, some manufacturers made some effort regarding innovating engineered graywater collection/treatment systems. This paper examines some of the graywater collection and treatment systems available in the market for use in a household and in some other buildings along with their weaknesses and strengths. Several systems were selected to show the diversity of systems available and the big picture. Designers of the systems tried to comply with the guidelines set by authorities on the use of graywater such as underground irrigation, no cross connections with potable water system, vented and sealed tanks, no human contacts, etc. At the commercial level, toilet flushing did not receive as much attention as landscape irrigation in the US. However, several successful cases for using graywater in toilet flushing were found in other countries like Germany, Australia, and the UK. The more complex systems are utilized for toilet flushing. Treatment units such as sedimentation, filtration (coarse filters and sand filtration), aeration, and disinfection were encountered. Biological treatment existed where multi‐house or multi‐user collection systems exist (e.g. hotel and multi‐storey residential building). Based on that overview, simplicity, flexibility, effectiveness, reliability, and cost are criteria that should be considered while designing a graywater system. These criteria were used in designing a graywater system in a single household in Fort Collins, CO. The system involved continuous recycling and aeration. Further system modifications included assessing the level of filtration and disinfection needed to maintain an effective system. Preliminary investigations showed acceptable levels of indicator organisms. Emphasis has been placed on microbial quality since local boards of health are concerned with human contact and exposure to enteric pathogens.

Select this Article		Wastewater Reuse Options for Gloucester County, New Jersey W. Walker, K. Jahan, J. Orlins, J. Everett, and J. Hasse ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)364 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper details investigations of the feasibility of wastewater reuse in Gloucester County, New Jersey. Wastewater can be a valuable resource in cities or towns where population is growing and water supplies are limited. In addition to easing the strain on limited freshwater supplies, the reuse of wastewater can improve the quality of streams and lakes by reducing the effluent discharges and loading that they receive. Wastewater may be reclaimed and reused for crop and landscape irrigation, groundwater recharge, or recreational purposes. Reclamation for drinking is technically possible, but this reuse faces significant public resistance. Wastewater reuse can also reduce the demand on valuable and diminishing potable water supplies and possibly save money for the costly investment of new water sources and supplies.

back to top

DIRECTION AND VISION

Select this Article		The Role of Risk Management in Sustainable Water Supply Planning Steven Nebiker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)365 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper focuses on developing sustainable water management strategies for Charlottesville, Virginia and the surrounding Rivanna River watershed and how they are being facilitated through risk management. Risk management is a means by which water systems can accurately quantify and manage risk using inflow forecasts, thus improving sytem reliability while offering potentially large cost savings through more intensive use of existing supplies and water conservation. The paper describes the advantages of risk management by highlighting the limitations of the safe yield approach and how the former is necessary for improved drought management and capacity planning. It also briefly discusses the basis of the instream flow needs and how risk management is applied to best meet them.

Select this Article		City of Seattle — Stormwater Low Impact Development Practices Richard L. Johnson and Peg Staeheli ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)366 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract As part of the City of Seattle's commitment to sustainable development, the City is implementing Stormwater Low Impact Development (LID) practices using numerous approaches. Two approaches are presented within this paper. First, the existing City of Seattle Stormwater, Grading and Drainage Control Code provides a variety of stormwater LID guidance to be used on various projects. Second, the City is also redeveloping a 129‐acre housing project using an entirely new approach towards stormwater management. The existing stormwater code implements both flow control and water quality treatment LID practices. This existing LID guidance will be updated as part of revisions to the stormwater code to meet the revised Municipal Stormwater National Pollutant Discharge Elimination System (NPDES) permit. The High Point redevelopment project is currently incorporating stormwater LID drainage practices. The High Point area was a low‐income housing development that is now being redeveloped as a mixed‐income housing development. This project redefines the stormwater management design approach to be used for infrastructure and site development. The collaboration for this project produced an unprecedented effort between the Seattle Housing Authority, Seattle Public Utilities, and other City agencies. As a result of this innovative design approach, a traditional low‐income housing development was enhanced by a more livable green space. The City stormwater code and the High Point project confirm Seattle's environmental commitment for sustainable development to maintain a high quality of life.

Select this Article		Advancing Sustainable Stormwater Management at Villanova University William C. Heasom, P.E. and Robert G. Traver, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)367 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Canon 1 of the ASCE code of ethics directs engineers to “comply with the principles of sustainable development in the performance of their professional duties.” This paper will explore some ways that the Villanova Urban Stormwater Partnership is advancing the art and practice of sustainable design for stormwater management in developing areas. The VUSP is a related series of innovative features (many on campus) coupled with an extensive educational, outreach and research effort. In breadth, it reaches and directly involves as participants a diverse population of designers, investigators and decision makers. This collective endeavor is contributing to significant and evolving changes in the way the hydrologic corollaries of urbanization are understood and addressed. In depth, the various features included in the VUSP (a stormwater wetland, an infiltration trench, a bioinfiltration island, etc.) are the subjects of individual and detailed research studies. The example considered in this paper, the bioinfiltration traffic island, has been investigated using a soils‐based method for quantifying the process of infiltration occurring over a wide range of environmental conditions. The inquiry suggests new approaches for integrating stormwater systems into sustainable developments.

back to top

GLOBAL PERSPECTIVES AND ISSUES

Select this Article		Project Sustainability Management in China's Hydropower Development Jian Liu, Ph.D., M. ASCE, Zhiyu Sun, Ph.D., Peng Lou, and Yongbai Chen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)368 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The project sustainability management in China's hydropower development is discussed in this paper. The experiences of the hydropower project development in China are reviewed. The sustainable management methods in the Three Gorges Project are described as an example. Some suggestions for sustainable development and management are presented from the viewpoint of sustainability management. People‐centered development and management should be promoted in the future hydropower project construction to ensure cost‐effective, environmentally sustainable and socially equitable development. Project management/agency, which is a project management system mainly used for public works in China, should be spread to the whole water conservation and hydropower projects to control the project cost and protect corruption.

Select this Article		Domestic Rainwater Harvesting Assessment to Improve Water Supply and Health in Africa's Urban Slums J. R. Cowden, J. R. Mihelcic, and D. W. Watkins ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)369 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract More than 50% of Africa's population will reside in cities by 2030, and hundreds of millions of those people will live in poverty conditions known as urban slums. In 2000, 14% of the Africa's urban population lacked access to improved water, which is one of the five criteria defining a slum household. This lack of access in urban slums is due primarily to inadequate service provision due to governments' inability or unwillingness to provide water to these often illegal settlements. Domestic rainwater harvesting is potentially a simple and cost‐effective solution to providing improved water to African urban slums. This paper uses GIS analysis to determine which African urban areas may benefit from rainwater harvesting technology under various scenarios. Maps are produced for use by slum communities, local agencies, and non‐governmental organizations to assist in preliminary assessment of rainwater harvesting technology implementation. The assessment reveals a potential 68% of urban slum dwellers able to obtain at least three months of daily 20/L/capita water supply and 23% of slum dwellers able to obtain at least three months 50/L/capita water supply using rainwater harvesting technology.

Select this Article		Comparison of Wastewater Treatment in Developed and Developing Countries J. Diaz and B. Barkdoll ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)370 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Wastewater treatment varies all over the world. Over 2 billion people in the world are without adequate wastewater treatment. This is due to economic reasons and mismanagement. While centralized treatment has some advantages, it may not be sustainable in the long term due to its high impact on the environment doe to resource consumption. Constructed wetlands may be a sustainable alternative for countries of all economic conditions.

back to top

SOCIAL AND ECONOMIC ISSUES

Select this Article		Revised Operation of Prado Dam and Reservoir for Additional Water Conservation Robert J. Stuart, P.E., M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)371 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The paper herein describes the development of a revised operating plan for a dam and reservoir. The revised operating plan was developed to promote additional water conservation capability at the dam. The paper describes the issues and events that culminated in the development of the revised plan. The paper describes the processes employed in the development of the revised plan. Finally, the paper summarizes the results of the processes and summarizes the benefits of the recommended revised plan.

Select this Article		Sustainable Management of Water Resources Infrastructure Tamara Butler Johndrow, P.E., George W. Annandale, P.E., and Alessandro Palmieri ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)372 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Annual sedimentation of only one‐half of one percent of the total reservoir storage volume in the world can threaten the sustainability this precious water resource. Historical approaches to dam design often did not consider the need to manage sediment in perpetuity, nor did they consider the costs of decommissioning a dam whose reservoir has filled with sediment. As such, intergenerational equity, a concept that requires that natural resources be developed and used in a way that accounts for the interests of all members of society, including future generations, has not been implemented. The life cycle management approach seeks to rectify this problem by considering intergenerational equity of reservoirs and dams. For example, the cost of dam decommissioning after a reservoir has filled with sediment is included in the economic analysis of dam and reservoir management in this approach. To avoid encountering this enormous expense, sustainable use of a reservoir becomes attractive economically. The Reservoir Conservation (RESCON) approach is the World Bank's implementation of the life cycle management concept. RESCON considers technical, economic, social, and environmental aspects of reservoir sustainability in terms of sediment management. The method provides a means to develop pre‐feasibility level concepts for management of new or existing reservoir facilities by means of the RESCON computer model. The RESCON approach has been applied in countries including Kenya, Morocco, and Sri Lanka. In the United States, the model has been applied to Strontia Springs Reservoir of Colorado and Lewis and Clark Lake (Gavins Point Reservoir) of Nebraska and South Dakota. The general approach and an example application are discussed.

Select this Article		Rational Water Tariff: A Tool for Sustainable Urban Water Management in India Mamata R. Singh, V. Upadhyay, and A. K. Mittal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)373 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The urban water supply sector in India is entrapped in a vicious circle of poor tariff structure to poor cost recovery and hence poor service delivery to consumers. Urgent steps are necessary for improving the management of urban water sector and thus ensuring sustainability. In the present paper, current status of water supply sector is discussed along with the details of different types of water pricing practices adopted in India and, problems associated with them. It is observed that in India, state governments generally set the minimum water tariff for various municipal bodies, which in turn have option to set the tariff above this minimum level for individual cities in order to recover cost. As a result, there is wide variety of water pricing practices across various cities in India. Design of rational water tariff structure though is very difficult and challenging but would balance various conflicting objectives such as affordability, economic efficiency, equity, and cost recovery etc. The present study presents a rationale water price structure, which could balance the major three dimensions (utility, consumer and environment) of urban water, leading to sustainable urban water management.

Select this Article		Developing Sustainable Behaviors through Community‐Based Social Marketing C. E. Johnston, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)374 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Environmental professionals, when seeking to effect change in the behavior of individuals, most commonly utilize the “public education campaign.” This form of social marketing typically consists of public information messages, brochures, posters, or other passive material aimed at raising the awareness of individuals around a given issue. The limitation of such an approach is that it necessarily treats the behavior of individuals as a product, thereby undermining the very goal it seeks to accomplish — namely, reminding individuals that they must take an active role in protecting their environment. In using social marketing, it is assumed that if a person is aware of the environmental impact of their actions, they will change their behavior. Yet, time and time again, awareness—even of economic self‐interest—does not result in meaningful behavioral change. Therefore, rather than depending primarily on an informational campaign to change resident attitudes, environmental professionals have more recently looked to community‐based social marketing to appeal to the individual. Community‐based social marketing is a strategic process that explores and identifies the barriers to changing behavior, structures a program around those barriers, exercises this strategy on a small scale, evaluates the results, and applies the process across a given target audience. This process is applied within the target community to identify the most meaningful barriers and solutions and to provide personal interaction with individuals. These methods provide significantly higher success rates compared to social marketing campaigns. Here, case studies detailing community‐based social marketing strategies that have proven successful are discussed.

back to top

BMP PERFORMANCE, MONITORING, AND COSTS

Select this Article		Measuring Total Volatile Suspended Solids in Stormwater to Understand the Influence of Organic Matter on BMP Performance James H. Lenhart, P.E. and Jeremiah M. Lehman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)375 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Total Volatile Suspended Solids (TVSS) is a method used to estimate the total mass of organic matter in a water sample by a method of dry ashing TSS samples. Data collected from sites in Washington, Oregon, New Jersey, and California are presented. The data indicate that there are some relationships between TVSS and TSS, TVSS and Dissolved Zinc. In general, the data suggested that as TSS or SSC concentrations increase the relative fraction of TVSS decreases. The data also indicate that as TVSS concentrations increase the relative fraction of soluble zinc decreases. It is hypothesized that the organics sequester soluble metals through chemical processes. Suggestions are provided for methods to reduce soluble nutrient discharge from BMP's by managing organic matter as part of the BMP design.

Select this Article		Monitoring of a Retention Pond before and after Maintenance Thomas P. O'Connor and James Rossi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)376 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The USEPA's Urban Watershed Management Branch has monitored stormwater drainage and best management practices (BMP) as part of its research program. One BMP being monitored is a retention pond with wetland plantings in the Richmond Creek (RC) watershed. This BMP, designated RC‐5, is owned and operated by the New York City Department of Environmental Protection (DEP) as part of the Bluebelt program. The Bluebelt incorporates BMPs on a watershed basis. Dedicated funding to the DEP programs allows for maintenance activity at Bluebelt BMPs. During monitoring performed in 2003 and 2004, BMP‐RC‐5 removed suspended solids (SS), but not chemical oxygen demand (COD). Calculated SS loads demonstrated a 61% removal, exceeding anticipated removals of 55–57%. Of three events monitored for COD, one had no removal, the second had a negative 146%, and the third had a 37% removal. The increase in COD during the second event may be due to biological activity in BMP‐RC‐5 and seasonal considerations, i.e., decaying leaves and wetland vegetation going into dormancy. The largest SS and COD discharges occurred on 12/11/03, which was the largest rain (>1 in.) and flow event monitored. Results indicated that the number of storms monitored was adequate to describe SS removal using a paired t‐test on composite influent and effluent data after applying log transformations. Directly calculating the significance, using a statistical test for randomly comparing two data sets of non‐paired results, indicated a 0.94 significance level in the log transformed SS results at a power of 0.5, just below 95% confidence. Maintenance activities, including cleaning of the forebay and stilling basin, were performed in the spring of 2005. Almost four truck loads of sediment and leaf litter, estimated between 46 to 48 yd³, were removed from the site. Monitoring during the fall of 2005 measured the effects of this maintenance activity, to better quantify seasonal effects of leaf decay and to assess scheduling of maintenance activity. Indications are that the maintenance activity significantly reduced the COD effluent.

Select this Article		Improved Extended Detention Basin Performance through Better Residence Time Control John R. Middleton and Michael E. Barrett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)377 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Extended detention basins are not used for stormwater quality management in many areas of the US because they generally do not achieve the 80% removal of total suspended solids required by many regulatory agencies. The objective of the described research was to modify the outlet of an existing basin to provide batch treatment of the runoff and provide more control over the hydraulic residence time., A solar powered automated valve and controller were developed and placed on the outlet of a pond in Austin, Texas in order to increase the detention time beyond the times achievable using an orifice. This allowed all of the diverted runoff to be retained in the basin for a variable preset period of time. The influent and effluent of the pond were monitored for suspended solids, nutrients, chemical oxygen demand, and total and dissolved metals. The suspended solids reductions in the pond were controlled by adjusting the residence time of the runoff in the basin in order to meet the required pollutant reduction. Additionally, the valve can be used to regulate flow into the receiving waters to control peak flow.

Select this Article		Performance Evaluation of Best Management Practices for Urban Storm Water Runoff H. S. Ramesh and K. R. Kiran ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)378 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Non‐point source pollutants in urban stormwater runoff depend mainly on land use pattern, human activities and rainfall characteristics. Studies on the characterization of street‐dust and stormwater runoff in three different land use pattern show various effects of runoff pollutant loading on receiving waters. The evolved pollutant loading equations predicts an increasing trend for most of the parameters. The most problematic pollutant identified is phosphate. Experimental studies on modified Best Management Practices (BMP) in attenuating the phosphate revealed that infiltration trench (BMP‐1) has a removal efficiency of 55%, detention basin (BMP‐2) with 40%, partial ex‐filtration trench (BMP‐3) with 75%, vegetative swales (BMP‐4) with 47% and horizontal flow filter drain (BMP‐5) with 60%. In most of the cases, for economical reasons, time of attenuation and maintenance viewpoint, vegetative grass swales may become better option of best management practices for urban storm water runoff.

back to top

BMP TREATMENT TECHNOLOGIES I

Select this Article		Applying a Vadose Zone Model to Stormwater Infiltration J. B. Mikula, S. E. Clark, and K. H. Baker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)379 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Urbanization has been responsible for an increase in the amount of impervious surfaces, leading to an increase in stormwater runoff and a decrease in groundwater recharge. Stormwater runoff contains pollutants, such as nutrients, pathogens, heavy metals, solids, organic compounds, pesticides, and chlorides, which have greatly contributed to the degradation of receiving waters due to surface discharge of stormwater. This has prompted stormwater managers to consider implementing more infiltration practices into their designs. However, past studies have shown that infiltrating stormwater could contaminate the groundwater, and in some cases contamination actually has occurred. Therefore, methods for easily predicting contamination potential need to be developed. Stormwater pollutants interact with the soils in the unsaturated zone as they migrate towards the groundwater. The specific type of soil and its properties have a profound effect on the movement of water and pollutants. Zinc and sodium chloride were chosen to be the pollutants of interest because of their prevalence in stormwater, solubility, and differing migration rates. Through the use of the SESOIL model, factors such as pollutant concentration, rainfall, vadose zone thickness, intrinsic permeability, organic content, and soil pH were evaluated to determine which ones have the greatest influence on pollutant migration. A factorial analysis (2⁶ full factorial) was used to evaluate the effects of these factors on the maximum penetration depth of zinc and sodium chloride. High and low values for the factors were selected from the literature and the NRCS soils database. The pollutants were treated as separate ions (Zn⁺², Na⁺, Cl⁻), and the length of each simulation was set at 1 year. Results indicated that rainfall was a common factor controlling Zn⁺², Na⁺, and Cl⁻ migration. Concentration was also influential in Zn⁺² migration, while intrinsic permeability affected Na⁺ and Cl⁻.

Select this Article		Experimental Analysis and Modeling of a Stormwater Perlite Filter José M. Adriasola, Jorge Gironás, and Bonifacio Fernández ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)380 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the study of a mixed porous media, composed of expanded perlite (EP) and nonwoven needle punched geotextile, used to remove suspended solids (SS) in urban runoff before it is infiltrated. Several laboratory procedures were designed to quantify the most important variables that characterize the performance of this filter media: SS removal efficiency (R) and the variation in time of filtration rate (Q). Different grain size distributions of EP, diverse SS concentrations, and different hydraulic and geometric conditions were tested in order to determine the most effective filter media in terms of the maximization of R and Q. A dimensionless parameter, the “global performance index” (GPI), was developed to reach this objective. Measured data were also used to build a dimensional model to represent the performance of the filter media mathematically. The theory, assumptions, derivation and performance of this model are presented, and then compared to an existent empirical model. The dimensional model better reproduces the observations, becoming a useful tool for the design, operation and evaluation of commercial porous media filters.

Select this Article		Evaluation of Retention Pond and Constructed Wetland BMPs for Treating Particulate‐Bound Heavy Metals in Urban Stormwater Runoff Swarna Muthukrishnan and Ariamalar Selvakumar ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)381 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The sources of heavy metals in urban stormwater runoff are numerous (e.g., highways, road surfaces, roofs) and the release of metals into the environment is governed by several complex mechanisms. Heavy metals in stormwater are associated with suspended particulate materials that vary from coarse (>75 micrometer) and fine particulates (<75 to 1 micrometer), to colloids (<1 micrometer). Stormwater runoff investigations increasingly focus on evaluating quality and the effectiveness of adopting best management practices (BMPs) to minimize pollutant input, including heavy metals, to receiving waters. Heavy metals in stormwater are primarily removed by sedimentation in BMPs such as retention ponds and constructed wetlands; these sediments may be toxic to benthic invertebrates and aquatic microorganisms. Information on heavy metals‐particulate association is therefore a fundamental requirement prior to using wetland and pond BMPs for treatability studies. Research is being conducted at the U.S. EPA's Urban Watershed Research Facility in Edison, NJ to evaluate the effectiveness of retention pond and constructed wetland BMP mesocosms to remove particulate‐bound heavy metals from roof and parking‐lot stormwater runoff. The research objectives include: (1) investigating the association of selected heavy metals (Al, Cr, Cu, Fe, Mn, Pb, and Zn) with fine particulates (20 to 0.4 micrometer) in stormwater runoff, (2) evaluating the relative removal of particulate‐bound as well as dissolved heavy metals in retention ponds and cattail wetland mesocosms, and (3) investigating the solid‐phase chemical associations of heavy metals in cattail wetland sediments by selective sequential extraction procedures and thereby assessing the potential for sediment toxicity and heavy metal bioavailability. This investigation comprises the study of eight separate storm events; three sampling events have been completed to date. Preliminary results showed that Fe and Al were primarily particulate‐bound (>20 micrometer); Mn was mostly soluble while Cu and Zn were primarily associated with fine particulates (10 – 1 micrometer) and in the dissolved fraction (<0.4 micrometer) in stormwater runoff. Also, the retention pond and cattail wetland mesocosms were effective in attenuating Cu, Zn, and Al. Preliminary results are also presented for the chemical fractionation of cattail wetland sediments.

back to top

BMP TREATMENT TECHNOLOGIES II

Select this Article		Nitrogen Removal from Stormwater: A Pilot Plant Research Project Daniel P. Smith, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)382 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A research pilot plant has been operated for over 150 days to investigate nitrogen removal from urban stormwater. Parallel zeolite and sand filters were operated at 0.125 gal/ft²‐day on storm pond water amended with ammonia nitrogen (NH₃‐N). The zeolite filter contained chabazite 500H with an ion exchange capacity of 2.5 meq./gram. NH₃‐N reduction was much higher in the zeolite filter for the first 28 days, presumably due to ion exchange. Adjustments to influent dissolved oxygen (DO) and NH₃‐N levels led to improved performance by both filters over the next 64 days. During a subsequent 14 day period, zeolite and sand filters reduced 0.781 average influent NH₃‐N by 93.3 and 86.7%, respectively. Nitrite and nitrate concentrations increased through both filters, indicating that nitrification had been established. Further analysis indicated that pond water contained organic nitrogen (ca 1 mg/L) that was not substantially removed though zeolite or sand filters. The organic nitrogen was predominantly dissolved organic nitrogen (DON) that was not retained by a 0.45 micrometer filter. To provide a preliminary assessment of non‐steady performance, a flowrate perturbation was performed to test columns containing zeolite and sand media. NH₃‐N levels rose appreciably in sand column effluent, while the column containing zeolite media was highly effective in preventing NH₃‐N breakthrough.

Select this Article		Performance of Upflow Filtration for Treating Stormwater Uday Khambhammettu, Robert Pitt, Robert Andoh, and Shirley Clark ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)383 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract One approach to the treatment of urban runoff is to treat the runoff from critical source areas before it mixes, with runoff from less pollutant areas. Some of the general features of critical source areas appear to be large paved areas, heavy vehicular traffic, and/or exposed heavy equipment, materials or products. The control of runoff from relatively small critical source areas (such as loading docks, fueling areas, small maintenance yards, etc.) may be the most cost effective approach for the treatment/reduction of stormwater toxicants. However, in order for a treatment device to be usable, it must be inexpensive, both to purchase and to maintain, and be effective. Upflow filtration of stormwater was tested during both controlled tests, and under actual rainfall conditions, during SBIR1 (Small Business Innovative Research) and SBIR2 research funded by the US EPA. This paper summarizes the work presented by Pitt, et al. and Khambhammettu. Upflow filtration was originally developed to overcome some of the problems associated with conventional filtration. The most serious problem is that downflow filters clog relatively quickly, reducing the treatment flow rate potential and total treatment capacity, potentially causing large amounts of the stormwater to bypass the treatment units. Clogging does not occur as fast with upflow filtration. One reason is that the heavier particles get drawn away from the filtration interface due to gravity and fall into the sump which is an integral part of the upflow filter design.

Select this Article		Enhanced Sand Filtration for Storm Water Phosphorus Removal Andrew J. Erickson, Peter T. Weiss, and John S. Gulliver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)384 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Batch and column studies were conducted on several media to determine the most effective method to enhance the dissolved phosphorus retention capacity of C 33 sand filtration. This study found that C 33 sand alone could retain some dissolved phosphorus but its capacity was quickly exhausted and therefore required media enhancements to improve the phosphorus retention capacity. Batch studies evaluated calcareous sand, limestone, three blast oxygen furnace (BOF) by‐products, aluminum oxide, and chopped granular steel wool and found that BOF by‐products increased pH levels above EPA guidelines and aluminum oxide did not significantly retain phosphorus. Column studies determined that calcareous sand and limestone retained more phosphorus as compared to C 33 sand but their fine grain size clogged the filter very quickly. Steel wool also retained more phosphorus than C 33 sand and did not clog the filter. Additionally, cost estimates show that steel wool enhancement would increase construction costs by roughly 3–5%. Fine iron oxide particles from the steel wool were observed in the effluent from the columns but any phosphorus attached to these particles is of limited bioavailability. A mass balance model was developed to predict phosphorus retention capacity of steel wool enhanced sand filtration based on contact time, influent concentration, and sum of phosphorus mass retained. Based on the results of the study, it is evident that steel enhanced sand filtration is an effective solution for removing dissolved phosphorus from stormwater runoff.

Select this Article		Stormwater Quality Benefits of a Permeable Friction Course Michael E. Barrett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)385 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This project documents the impact of a permeable friction course overlay on the quality of highway stormwater runoff. A permeable friction course (PFC) is a layer of porous asphalt approximately 50 mm thick which is often applied on top of conventional asphalt highways to enhance safety. The quantity and quality of stormwater runoff from a four‐lane divided highway in the Austin, Texas area was monitored before and after the installation of a PFC. Observed concentrations of 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. Concentration reductions were observed for suspended solids (92%), total lead (90%), total copper (51%), and total zinc (74%). Observed concentrations of PAHs were below the detection limit for both pavement types.

back to top

DESIGN WITH URBAN CONSTRAINTS

Select this Article		Planes, Drains, and Automobiles: Design Criteria for Storm Water Drainage Facilities at Lambert — St. Louis International Airport Expansion M. T. Buechter and J. L. Weiland ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)386 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Lambert‐St. Louis International Airport, a major commercial airport, is located on 465 hectares in northwest St. Louis County. To enhance inclement weather operations the City of St. Louis has undertaken an ambitious airport expansion plan located on approximately 445 hectares west‐southwest of the existing airfield limits. This plan includes the addition of a 2,700 meter by 46 meter Category III runway, a dual parallel taxiway system and relocation and tunneling of Lindbergh Boulevard. Due to the size and complexity of this project, several regulating authorities are involved. This paper will document the challenges that faced the designers to determine the correct design criteria and balance conflicting design requirements. The three important aspects of the stormwater design which were addressed include: (1) The Cowmire Creek watershed and the proposed Cowmire Creek detention basin, (2) The Coldwater Creek watershed and proposed Coldwater Creek detention basin, and (3) Stormwater drainage tunnels at two low points of Lindbergh Boulevard relocation.

Select this Article		Residential Manmade Lake System Design for Storm Water Treatment Bruce M. Phillips ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)387 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Aquascape facilities have traditionally been considered ornamental and landscape features primarily serving aesthetic purposes in golf courses, parks and residential developments. However, aquascapes can be applied with innovative design elements to function as primary infrastructure facilities in urban developments, replacing typical stormwater facilities and adding value to the community. These specialized types of aquascape systems integrate a living ecosystem into an urban environment, which maintains water quality through natural biological processes. Planned aquascape features, particularly in semi‐arid areas, offer a combination of many unique advantages for storm water management as well as other benefits that are not available in conventional engineered systems, including: (1) continuous year‐round natural treatment process, (2) storm water conveyance and storage, (3) exceptional water quality, (4) flood protection, (5) combined landuse elements, (6) significantly reduced infrastructure costs, (7) dry weather flow treatment, (8) landscape and aesthetic treatment with natural water system, (9) increased surrounding land values, (10) natural ecosystem benefits, (11) recreational design feature, and (12) urban design element for communities. The necessity for storm water pollution control has received increased public attention, especially with the escalating environmental regulations focusing on non‐point source pollution and protection of receiving waters. As of March 2003, the Phase 2 portion of the NPDES (National Pollutant Discharge Elimination System) storm water regulations require developers and municipalities alike to more seriously address storm water quality through the implementation standard structural control measures or Best Management Practices (BMPs). These methods generally have limited pollutant removal effectiveness, perform single functions, require considerable land, maintenance issues, construction costs, difficult integrating with the land plan, and are typically unsightly having limited aesthetic appeal to the community. Integrating large scale specialty aquascape systems through constructed lakes, ponds, small creeks, or other water features can replace traditional underground drainage infrastructure and provide highly effective storm water treatment resulting in water quality not available through other conventional methods.

Select this Article		The Utilization of Fly Ash for Sediment Stabilization during the Holmes Lake Restoration Project Timothy P. Gokie, P.E. and Ryan Beckman, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)388 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Often the most difficult issue to address during the planning for the restoration of an urban lake is where to waste the vast amounts of sediment that will be excavated from the lake. In an urban setting, open space is limited and real estate values make it cost prohibitive to purchase land for wasting excavated sediment. Hauling the material to rural areas increases congestion of city streets and can also be cost prohibitive due to the long‐haul distance. Furthermore, accidental dumping of sediment along with repeated heavy truckloads can significantly impact the design life of local streets, adding indirect costs to the option of hauling the sediment offsite. As part of the Holmes Lake Restoration Project in Lincoln, Nebraska, 330,000 cubic yards of deposited sediment were excavated across the lake bottom. Due to its urban setting and other site constraints, there were only eight acres of ground available for onsite disposal. The closest offsite location identified for disposal was more than six miles away, potentially adding significant transportation costs to the project. In order to waste the material onsite, the saturated sediment had to be stacked more than thirty‐five feet deep. Consequently, the material had to be dried quickly and placed on steep slopes. Several conventional sediment management techniques were investigated for stabilizing the dredged sediment, but all were found to be ineffective. The utilization of a chemical drying agent was the only viable option remaining. It was determined that fly ash incorporation would be the most economical means of stabilizing the sediment from Holmes Lake. The use of fly ash during the Holmes Lake Restoration Project allowed the project to be completed in a timely manner and provided significant cost savings. Type ‘C’ fly ash, a byproduct of coal combustion, was found to be effective in drying the wet sediment quickly. Furthermore, the fly ash added strength to the sediment, allowing it to be placed on steep slopes without the possibility of slumping or eroding back into the lake.

back to top

GENERAL URBAN WATERSHED CONSIDERATIONS

Select this Article		Pollutant Potential from Building Materials: Laboratory and Field Evaluations Shirley E. Clark, Julia M. Hafera, J. Bradley Mikula, James C. Elligson, Brett V. Long, and Melinda M. Lalor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)389 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Development in sensitive watersheds continues to pose environmental problems for receiving waters. Materials, such as galvanized metal, concrete, asphalt and wood products, may release pollutants into urban runoff and snowmelt; however, the long term effect of commonly‐used building materials on the environment has not been quantified. Laboratory testing on common roofing materials indicated that the potential for release (primarily nutrients, hydrocarbons, pesticides, and metals) is substantial. Further testing on painted, galvanized roofing tiles that were exposed to the Pennsylvania climate for 60+ years indicated that material continued to be released from these panels — indicating a deeper reservoir than simply the loss of a sacrificial surface coating. The ongoing research project involves testing a variety of construction materials (roofing materials, treated and untreated woods) to determine their long‐term pollutant release after typical installation and exposure to the weather. The goal is to develop a better understanding of how the aging and exposure processes will impact the release over time. Understanding the ‘release vs. time’ of a pollutant from a material will be crucial for translating the laboratory results to the actual environment and to developing predictive models for evaluating new materials for their pollutant potential.

Select this Article		A Watershed Process to Quantify and Facilitate Ecosystem Improvements through Flow Regime Restoration Mark Mittag, Jack Bails, Brent Brown, Mary Jo Kealy, and Dan Medina ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)390 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The ecological integrity of the Great Lakes has declined due to a number of factors including water withdrawal, physical habitat modifications, and changes in land use. Research has shown that restoring the watershed's natural flow regime is an essential element in restoring impaired fisheries and other beneficial aquatic resources. This paper presents a process that focuses on restoration of a watershed's flow regime and quantification of the resulting ecosystem improvements. This process was developed for the Great Lakes basin but it is transferable to other ecoregions. The methodology recognizes that water quality, habitat, and various human factors affect watershed management decisions, but emphasizes flow regime as the main restoration goal for watershed management decisions that will lead to ecosystem restoration. The basic premise is that absent the necessary hydrology, the presence of all other factors would not be sufficient to restore aquatic biota. This correlation between flows and the ecosystem has been well documented. The process includes an accounting system and protocols to quantify hydrologic improvements resulting from changed land and water practices and a process to facilitate flow regime restoration transactions. Two pilot watersheds are analyzed: (1) Upper Rouge River watershed, near Detroit, Michigan and (2) Menomonee River watershed, near Milwaukee, Wisconsin. The potential users of this process include landowners, public management authorities, and private entities that need to evaluate land and water management decisions to generate resource improvements. The process is relevant to many resource improvement drivers, such as the public relations value of demonstrating good stewardship, stormwater regulations, smart growth, compensatory restoration for natural resource damages, leveraging of private funding sources, and formulation of alternate environmental projects in lieu of monetary penalties to mitigate negative impacts. The results indicated that the methodology provides a quantification tool for flow regime restoration using stormwater best management practices (BMPs). Potential market‐based implementation incentives for flow regime restoration BMPs were identified.

Select this Article		Removal of Pollutants by a CDS Unit at a Major Storm Outfall in Florida Betty Rushton, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)391 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A major storm drain pipe was retrofitted with a Continuous Deflective Separation (CDS) unit and a linear pond to help treat stormwater discharged from an urban drainage basin in Tampa, Florida. The CDS technology is designed to remove large sized particles such as litter, leaves, twigs, sand and paving residue from storm runoff. Results of this research suggest that it removes these gross solids very well, but it does not remove the dissolved and suspended particles present in the water column. The CDS unit did remove levels of polycyclic aromatic hydrocarbons (PAHs) at concentrations many times higher than levels considered toxic to benthic organisms. Since PAHs do not easily dissolve in water, they are rarely measured in water quality studies, but are considered a serious problem in sediments in portions of Tampa Bay. The data did not support the idea that the leaves collected by the CDS unit leached nutrients and increased their concentrations in the water that left the CDS unit, but this result may be influenced because leaching had already occurred while the leaves and discharge water traveled through the storm drain together. If litter and large sized particles are the pollutants of concern in a drainage basin, a CDS unit is a good solution, but if dissolved or suspended particles, especially nutrients, are a problem, a CDS unit will not reduce those pollutants. A CDS unit is probably best suited as the first element in a series of stormwater treatment methods.

back to top

LOW IMPACT DEVELOPMENT I

Select this Article		Rainwater Harvesting, Low Impact Development Strategies, and Meeting the National Pollution Discharge Elimination System (NPDES) Stormwater Discharge Standards Heather Kinkade‐Levario ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)392 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The National Pollution Discharge Elimination System (NPDES) was established to control development generated pollutants that are discharged into natural drainage systems. NPDES regulates point source pollution that enters surface bodies of water including water pollutants such as effluent from factories, power plants, sewage treatment plants, large construction sites, storm sewer systems, and stormwater runoff. Stormwater runoff—the main subject of the paper—is listed with these other toxic water sources because it too can have extremely poor water quality by picking up and removing toxins from an urban environment as it moves through a developed site. The larger the development, the more essential it is to deal with its generated pollutants. Rainwater harvesting deals with the rain that falls on a site and can be either a passive system allowing gravity to do the work or can be an active system where the rainwater is collected in cisterns for future use. Stormwater can be collected off rooftops or ground level catchments. The water can be used for either non‐potable or potable uses. Water collection alone can not remove the threat of stormwater pollutant transport however; combining collection with low impact development strategies increases the potential for eliminating stormwater transport of pollutants. Low impact development strategies deal with the way a site is designed and graded and deals with strategies such as reducing impervious areas, using permeable pavements, eliminating curbs or allowing stormwater to move through curbs, or installing strategies such as rain gardens and bioswales. Responsible stormwater management incorporates rainwater harvesting and low impact development strategies to help streamline NPDES requirements. This paper discusses a common goal in green building development projects, which is to generate “no net” increase in runoff from a site and improve water quality of stormwater that must leave the site. This goal is met with two basic concepts: rainwater harvesting and low impact development strategies. Along with a description of the two basic concepts, a stormwater case study is provided at the end of this paper to demonstrate applicability.

Select this Article		Low Impact Development Strategies and Tools for NPDES Phase II Communities B. Rittenhouse, C. Kloss, and N. A. Weinstein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)393 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Small municipalities across the United States are faced with finding cost‐effective and reliable stormwater management techniques to comply with NPDES Stormwater Phase II regulations. Constrained by limited capital budgets, choosing stormwater BMPs that maximize financial investment is an important component of the selection process. Low Impact Development techniques allow Phase II communities to implement effective stormwater management programs while also providing the opportunity to lessen the economic impacts of compliance. While possessing the ability to maintain and restore natural hydrology, LID also has the ability to reduce infrastructure costs, improve aesthetics, and meet multiple natural resource protection criteria. Importantly, LID can also be used to satisfy five of the six minimum requirements of the Phase II rule. Institutional barriers still limit greater use of LID and require municipalities to review current zoning codes and ordinances to not only remove these barriers, but also encourage adoption of LID.

Select this Article		Hydrologic and Pollutant Removal Performance of a Bio‐Infiltration BMP J. R. Ermilio and R. G. Traver ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)394 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Infiltration Best Management Practices (BMPs) have become a major component of stormwater designs. These BMPs are designed to address runoff volume and quality criteria's, augmenting and in some cases replacing traditional detention based methods. While the function of the Bio‐Infiltration BMP's may be understood, many questions remain on their design, maintenance, and how to best utilize these devices as part of a watershed plan. To address these issues, Villanova University has constructed and is monitoring a Bio‐Infiltration “RainGarden” through the Villanova Urban Stormwater Partnership (VUSP). Flow data from this effort has been used to create a representative computer model of the watershed, allowing analysis of its performance. Results indicate that the site outperforms the original design specifications, and that maintenance may be required in the future to continue its high level of performance.

back to top

LOW IMPACT DEVELOPMENT II — PANEL DISCUSSION

Select this Article		The SPAW Model: Application to Infiltrating BMP Facilities William C. Lucas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)395 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The recently formulated SPAW model provides comprehensive soil moisture accounting in agricultural ecosystems. This paper examines how SPAW can be applied to infiltrating BMPs under the much higher runoff loading rates typical of urban runoff BMPS. Using SPAW, it is thus possible to better project the important BMP performance characteristics of interception percentage and retention time as a function of media infiltration properties. SPAW results can then be integrated with detention routing procedures to project runoff volume and peak flow reductions provided by distributed BMP facilities. A case study of biofiltration swales with check dams to provide detention storage is then presented. In over 5 km of biofiltration swales the effect of stone check dams placed every 30 to 35 meters to provide detention storage has been modeled for its effect upon infiltration volumes. This presentation summarizes the hydrological approach, and presents hydrographs that demonstrate the very promising potential of distributed infiltration BMPs.

back to top

MANAGING FOR TMDLS I

Select this Article		BMP Decision Support System for Evaluating Watershed‐Based Stormwater Management Alternatives Mow‐Soung Cheng, Chris A. Akinbobola, Jenny Zhen, John Riverson, Khalid Alvi, and Leslie Shoemaker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)396 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The proper selection and placement of Best Management Practices (BMPs) is a critical part of the stormwater planning effort. Established urban and newly developing areas must establish cost effective means for restoring existing sites, minimizing impacts to new sites, and provide general site planning for future growth. Prince George's County, Maryland in the Washington D.C. metropolitan area has developed a BMP analysis system to support analysis and decision making for stormwater management planning and design at the watershed level. This system supports watershed hydrologic and water quality analysis, simulation of various innovative BMPs, and selection/placement optimization of suitable BMPs that will achieve the goals, defined by a user. This system helps planners determine which alternatives will yield the greatest benefit by automatically assessing several key site‐specific factors. Housed in the ESRI ArcGIS environment, the system provides visualization and GIS processing support for developing networks including sequences of land uses, BMPs, and stream reaches. ArcGIS also serves as an interface for BMP placement, BMP attribute data input, and as a platform for managing the decision optimization component. The system then launches a stand‐alone BMP simulation and evaluation module. Since the module is a process based simulation model for BMPs, it provides a technique that is sensitive to local climate and rainfall patterns as well as BMP size, design, and relative placement on the site. The system incorporates a meta‐heuristic optimization technique to find the most cost‐effective BMP placement and implementation plan that best satisfies a controlled target and fits within a fixed cost budget. A case study application is presented to demonstrate the application of the system. The case study involves a highly urbanized area in the Anacostia River watershed, located within the boundaries of Maryland and the District of Columbia. Several BMPs such as bioretention, green roof, porous paving and rain barrels are proposed, which minimize runoff, improve water quality, and provide water reuse opportunities. The modeling system is used to identify and evaluate various alternatives to determine the most cost‐effective types and combinations of BMPs that best minimize the frequency and size of runoff events thereby also reducing the magnitude and frequency of combined sewer overflows to the Anacostia River.

Select this Article		A Model of Optimal Best Management Practices Placement S. K. Chiu, J. T. Kuo, and P. H. Hsieh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)397 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The nonpoint source pollution control is in the beginning stage in Taiwan. The techniques of nonpoint source pollution control with Best Management Practices (BMPs) have also been under limited research. The soil and water conservation and environmental laws provide regulations that require the land developer to detain excessive stormwater runoff and sediment resulted from any significant development in the watershed. Most of stormwater quantity and quality controls have been designed at the local or on‐site level, but not at the regional or watershed level in a comprehensive and systematic manner. The purpose of this study is to establish an optimization model for the optimal placement of structural Best Management Practices (BMPs) on the watershed scale. The complete model consists of two interacting components; i.e. a reservoir water quality model and an optimization model with genetic algorithms (GAs). This research chooses Fei‐Tsui Reservoir and its watershed in northern Taiwan for case study. In the optimization model, the objective function is to minimize the total cost of BMPs and its constraints considering water quality standards for pollutant concentrations in rivers and reservoir. The model developed in the present study can be used as an efficient approach to the implementation of BMPs in the entire watershed to mitigate the impact of stormwater pollution on the receiving water bodies.

Select this Article		SUSTAIN — An Evaluation and Cost‐Optimization Tool for Placement of BMPs Fu‐hsiung Lai, Jenny Zhen, John Riverson, and Leslie Shoemaker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)398 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract To assist stormwater management professionals in planning for best management practices (BMPs) implementation, the U.S. Environmental Protection Agency (USEPA) is developing a decision‐support system for placement of BMPs at strategic locations in urban watersheds. This tool will help develop, evaluate, select, and place BMP options based on cost and effectiveness. The system was formerly called the Integrated Stormwater Management Decision Support Framework (ISMDSF), but will be tentatively called the System for Urban Stormwater Treatment and Analysis INtegration (SUSTAIN). SUSTAIN, a generic public domain framework, will provide a means for objective analysis of management alternatives among multiple interacting and competing factors. The desired outcome from the system application is a thorough, practical, and informative assessment considering economic, environmental, and engineering factors. SUSTAIN has seven key components: framework manager, ArcGIS interface, watershed model, BMP model, optimization model, post‐processor, and Microsoft Access database. They are integrated under a common ArcGIS platform. SUSTAIN supports evaluation of BMP placement at multiple scales from a few city blocks to large watersheds.

back to top

MANAGING FOR TMDLS II

Select this Article		Application of the Community‐Based Watershed Management Planning Process to Preserve Cunningham Lake J. Farnsworth and P. Slaven ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)399 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Community‐Based Watershed Management Plan (CBWMP) for Glenn Cunningham Lake comes at a crucial moment in the reservoir's life. Experience with other Omaha Metro area reservoirs indicates that although significant land treatment in the reservoir's agricultural watershed translates to borderline acceptable water quality, significant watershed development will result in lake degradation and loss of beneficial uses. The potential for degradation was a focal point in the management planning effort with project stakeholders choosing to adopt an aggressive protection plan designed to maintain and enhance reservoir quality throughout watershed development. The project sponsors understand that development of a relevant and implementable management plan requires the formation of a broad‐based coalition of public, private, and governmental stakeholders. To this end, the planning process was guided by a Watershed Advisory Council (WAC) comprised of watershed farm owners/operators, acreage owners, reservoir users, and concerned citizens. Additionally, technical guidance was provided throughout plan development by a Technical Advisory Team (TAT) comprised of personnel from ten local, state and federal agencies and departments with expertise ranging from water quality modeling to comprehensive land‐use planning. Together, the WAC and TAT established water quality goals for Cunningham Lake and evaluated various combinations of structural and non‐structural management practices designed to enhance and protect reservoir water quality, aesthetics, and recreational value now and into the future. After analyzing the various management strategies and protective management practices, the project stakeholders have chosen to adopt a comprehensive management plan that will buffer the reservoir from development‐related degradation through a combination of structural protective measures and promotion of conservation‐minded watershed development.

Select this Article		Fecal Coliform Impairment in Edwards Run, New Jersey Kauser Jahan, Diana Garcia, and Joseph Orlins ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)400 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water quality within the Edwards Run Watershed, located in Mantua Twp, Gloucester County, New Jersey, is being assessed through an integrated monitoring program. Edwards Run is approximately 6,964 acres and its land uses are primarily agricultural and residential. The New Jersey Department of Environmental Protection has classified Edwards Run as severely impaired by fecal coliform and phosphorus and has listed the Run in the Integrated Water Quality Report Sublist 5. This report lists impaired water bodies that do not have TMDL values. A monthly monitoring of nutrients (nitrate and phosphorus) and fecal coliform bacteria for the Run confirms that Edwards Run is an impaired water body in terms of fecal contamination and phosphorus concentrations. Monitoring results indicate that fecal coliform and phosphorus levels are frequently exceeding New Jersey surface water quality standards. Current studies are focusing on locating non point sources of pollution and presenting best management practices to protect the Run and the watershed.

back to top

PROTECTION AND RESTORATION OF URBAN STREAMS

Select this Article		Assessing Reach‐Based Restoration Practices in an Urban Steam from a Watershed Perspective Ying Wang and Edwin E. Herricks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)401 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Stream restoration using a variety of channel habitat improvement techniques are predominantly reach based. Although this reach focus is appropriate in natural streams in largely undisturbed watersheds, when channel modification is pervasive, as in urban watersheds, a reach based approach may lead to a patchwork of inadequate or the inappropriate application of best management practices. In urban settings it is particularly important to understand watershed potential as a part of the selection of best management practices for stream restoration. This paper reviews the development of methods to integrate hydraulic, hydrological, geomorphological, and ecological information to assess the potential for naturalization in urban watersheds. We use indicators of hydraulic variability as a surrogate for habitat and develop procedures to relate characteristics of hydraulic variability to restoration needs in a watershed.

Select this Article		Evaluating the Accotink Creek Restoration Project for Improving Water Quality, In‐Stream Habitat, and Bank Stability Scott D. Struck, Ariamalar Selvakumar, Ken Hyer, and Thomas O'Connor ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)402 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Increased urbanization results in a larger percentage of connected impervious areas and can contribute large quantities of stormwater runoff and significant quantities of debris and pollutants (e.g., litter, oils, microorganisms, sediments, nutrients, organic matter, and heavy metals) to receiving waters. To improve water quality in urban and suburban areas, watershed managers often incorporate best management practices (BMPs) to reduce the quantity of runoff as well as to minimize pollutants and other stressors contained in stormwater runoff. It is well known that land‐use practices directly impact urban streams. Stream flows in urbanized watersheds increase in magnitude as a function of impervious area and can result in degradation of the natural stream channel morphology affecting the physical, chemical, and biological integrity of the stream. Stream bank erosion, which also increases with increased stream flows, can lead to bank instability, property loss, infrastructure damage, and increased sediment loading to the stream. Increased sediment loads may lead to water quality degradation downstream and have negative impacts on fish, benthic invertebrates, and other aquatic life. Accotink Creek is in the greater Chesapeake Bay and Potomac watersheds, which have strict sediment criteria. The USEPA (United States Environmental Protection Agency) and USGS (United States Geological Survey) are investigating the effectiveness of stream restoration techniques as a BMP to decrease sediment load and improve bank stability, biological integrity, and in‐stream water quality in an impaired urban watershed in Fairfax, Virginia. This multi‐year project continuously monitors turbidity, specific conductance, pH, and water temperature, as well as biological and chemical water quality parameters. In addition, physical parameters (e.g., pebble counts, longitudinal and cross sectional stream surveys) were measured to assess geomorphic changes associated with the restoration. Data from the pre‐construction and initial post‐construction phases are presented in this report.

Select this Article		Incorporating Natural Stream Protection into Municipal Infrastructure Design: A Kansas City Model William J. Heatherman, P.E., James M. Melvin, P.E., and Robert Prager, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)403 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Natural stream preservation was a key feature of the 2003 update to a model storm drainage design criteria used in the greater Kansas City area. The criteria contained detailed guidance on buffer zones and standards for construction in and near the stream. Standards were provided for culvert, bridge, and utility crossings, storm drain outfalls, flood control projects, floodplain fills, and bank stabilization measures. Guidance and discussion was provided for hydrologic controls, systematic grade control, and stream restoration. The criteria focused on practical guidelines for typical urban construction and deliberately avoided focusing on more complex stream restoration. A standardized method of data gathering and stream assessment was presented. The criteria (Section 5600) is published and maintained by the Kansas City metropolitan chapter of the American Public Works Association and can be downloaded at http://www.kcapwa.net/specifications.asp. This paper also discusses some of the philosophy and reasoning behind the criteria.

back to top

REAL TIME CONTROL OF CSO

Select this Article		Initiating Sewer System Real Time Controls in Cincinnati N. U. Schultz, R. M. Horvath, and D. W. Moughton ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)404 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper summarizes the development and implementation of the Ross Run Real Time Control Project. The Metropolitan Sewer District of Greater Cincinnati (MSDGC) investigated sewer system real time controls as one of the alternatives in the long term control planning for combined sewer overflows (CSOs). The investigation revealed that real time controls had the potential to significantly reduce the frequency and volume of overflows at selected locations, but would not provide sufficient control to fully achieve CSO planning objectives; e.g. wet weather volumetric control above 85 percent. Nevertheless, when MSDGC negotiated a Consent Decree governing overflow reductions, it was agreed to assess and implement real time controls at priority sites. MSDGC staff were reluctant to commit significant resources to a technology, real time control of sewers, with which they had no experience and which had not been proven in the local sewer system. They selected one site, the Ross Run site, where the preliminary studies projected significant potential for overflow reduction with comparatively uncomplicated real time control technology. A local consultant, BBS Corporation, teamed with others (XCG Consultants and CH2M HELL) to bring international experiences to this initial test in southwestern Ohio. This paper discusses the range of questions raised by those making planning and design decisions essential to implementing the first local real time controls. The paper explains questions by the planners interested in long term cost benefit to those of the operator wondering how often the facilities and instrumentation would require maintenance and calibration for reliable service. The questions were addressed through research of experiences elsewhere, coupled with discussion of how those experiences apply in constructing and operating the MSDGC real time sewer controls. The Ross Run real time control design is scheduled to bid in late 2006 and be constructed in early 2007.

Select this Article		Milwaukee Case Study in Example Evolution of Sewer Controls Steve Heinz, P.E. and Nancy U. Schultz, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)405 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Milwaukee Metropolitan Sewerage District (MMSD) operates a sewer interceptor system with the aid of one of the most extensive real time control networks in the country. This sophisticated system began 90 years ago when the interceptor sewers were installed with mechanically operated movable gates that restricted flows into the interceptors in response to increasing flow depths in the trunk sewers. By the 1960s, the controls included the original tilting gates, several pump stations operated in response to wet well levels, and about 25 sluice gates that were manually adjusted twice each year in response to seasonal precipitation patterns to direct flows towards, or away from, the Milorganite production. In the 1980s MMSD incorporated evolving remote sensing instrumentation, telemetry, and computer controls to automate the system. Since 2000 MMSD has refined telemetry, instrumentation, and operating strategies to further the continuous improvement of this innovative system. Most recently the real time controls were expanded to aid the Department of Transportation in achieving stormwater quality objectives for downtown highway interchange drainage. This paper summarizes the unique components of the controls incorporated into the system at each stage in the nearly 100 year evolution. The paper also summarizes the motivation, costs and system performance improvements associated with each major stage of the real time controls evolution. For the more recent innovations (those since 1980), the paper discusses the alternatives considered and the reasons for selection of those options implemented. The paper concludes with a summary of the benefits attributed to the real time control network. The benefits include reduced capital costs to achieve high levels of wet weather performance, improved tracking and reporting of system performance, improved real time identification and resolution of system problems, and decreased safety and environmental risks associated with maintenance of the diversions.

Select this Article		Real Time Control of Sewers: US EPA Manual Mary Stinson and Z. C. Vitasovic ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)406 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract U.S. EPA published a manual on design and implementation of real time control (RTC) for managing wastewater conveyance networks. The intended audience are the practicing engineers who are considering RTC to enhance the operational aspects of their sewer networks.

Select this Article		Real Time Control Implementation within a Combined Sewer System: An Operational Perspective Angela Akridge, P.E. and David Carty ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)407 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Whether you're planning to implement a multi‐million dollar robust Real Time Control (RTC) system or a scaled‐down simple version, there are several critical elements necessary for successful implementation and utilization by the Publicly Owned Treatment Works (POTW) staff. These critical components range from changing performance expectations to inclusion of the wastewater treatment plant operators and collection systems staff in all phases of program development and implementation. The Louisville and Jefferson County Metropolitan Sewer District (MSD) has initiated the second phase of their RTC program, with plans to ultimately implement a program targeted to cost approximately $83M. The in‐line control portion of the program is targeted to cost approximately $30M, with the remaining cost for off‐line storage facilities. The first phase contained five control points and is projected to provide a system‐wide average annual overflow volume reduction of 10 to 20%. The second phase, currently being designed, includes the addition of four control points. Ultimate build‐out of the entire RTC program is targeted to be approximately 20 control points. During the planning, design and implementation of the first phase, Louisville MSD staff successfully navigated past an intense learning curve. This paper will summarize their lessons learned, offering advice on program implementation which may assist other POTWs currently considering implementation of similar programs.

back to top

REGIONAL PERSPECTIVES ON BMP WATERSHED MANAGEMENT

Select this Article		Stormwater Best Management Practices Assessment for the City of Lincoln, Nebraska Tony Dean Krause, John Stansbury, Bruce Dvorak, and David Admiraal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)408 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The objective of this research was to assess BMP performance and implementation in Lincoln, Nebraska. In order to accomplish this objective, four tasks were established: sampling of stormwater runoff at eight sites located upstream of Holmes Lake, inspecting BMPs at construction sites in Lincoln, sampling and analysis of soil phosphorus levels in the Holmes Lake watershed, and conducting discussions with professionals involved with stormwater management in Lincoln. Based on the information collected during these tasks, several recommendations regarding the BMP assessment process are made including: recommendations for sampling site selection, an inexpensive flow monitoring method, and a rapid construction site BMP assessment protocol.

Select this Article		Water Demand Estimation Using Land Use and Population Growth Information: A Case Study in Salt Lake County, Utah Wafa Hasan and Jagath Kaluarachchi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)409 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water shortages cause deterioration of standard of living and pose threats to overall societal prosperity. Water stress is manifested when the demand for water exceeds the available resources or when poor water quality restricts the water use. Water scarcity and the growing demand for good quality water in many urban areas have initiated efforts to develop optimal water resources management measures. Assessment of available water resources and the prediction of water demand are essential for proper water resources planning and management. In classical water demand estimations, population growth is the primary decision variable. In this work, we propose a methodology to predict the water demand in a major metropolitan area using both population growth and land use change estimations. The methodology is demonstrated for the fast growing Salt Lake County, Utah. The results showed that the water demand estimated using the proposed methodology is higher than those predicted by using the population growth models only. This observation suggests that land use changes may play an important role in water resources planning and management.

Select this Article		City of Newport Beach Storm Drain Diversion Study Ying Poon, P.E. and Sherilyn Kimura, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)410 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A study was conducted to assist the City of Newport Beach to decide which of the five major storm drain flows should be diverted to a sewage treatment plant during the summer months to lower bacteria levels in Newport Bay. The study consisted of a field program to monitor both flow and bacteria levels of each storm drain and outfall to determine the storm drain bacteria loading to Newport Bay. Based on the data collected, numerical modeling was used to evaluate the impacts of the storm drains to Newport Bay. A relative comparison was made between the storm drains to determine the storm drain impacts to Newport Bay. Out of the five storm drains, two were found to have the least impact and were not recommended for further consideration. For the remaining three storm drains, the evaluation did not show that a single storm drain had the greatest impact to the entire Newport Bay. Instead, each storm drain had the greatest impact to a particular region of Newport Bay.

Select this Article		Prioritizing Stormwater Capital Improvement Program (CIP) Projects — Lincoln, Nebraska Lalit Jha, P.E., Devin Biesecker, P.E., Jonathan Jones, P.E., and J. D. Johnson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)411 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract All communities are faced with the challenge of identifying and prioritizing stormwater capital improvement program (CIP) projects each year and over an extended period of years. Which drainage system needs to be upgraded, rehabilitated or need system extension? Which drainage problem area should be addressed first? Where is the “real” source of drainage problems or flooding complaints? Are we causing problems downstream by resizing a structure upstream? Lincoln is faced with these questions, and the difficult task of setting priorities and implementing an appropriate capital improvement program (CIP). Historically, municipalities have developed CIPs by relying on a “reactive” approach, where the problems that draw the most complaints get the attention first. But these reactive responses often do not address the “root” cause of the stormwater problems and can exacerbate problems elsewhere. The City of Lincoln in coordination with its consultant (JEO Consulting Group, Inc., Wright Water Engineers, Inc., and Black and Veatch) went through a rational and multifaceted approach to develop a “proactive” system to set priorities and implement a stormwater CIP each year. Objectives of the process included: (1) Develop a “proactive” prioritization methodology, (2) Identify and prioritize stormwater CIP projects, and (3) Create GIS coverage and enhance the City's stormwater database. The CIP stormwater projects identified and prioritized through this process have allowed the City to prepare a proactive stormwater CIP, rather than a program that merely reacts as problems occur. The prioritization methodology and criteria used to select stormwater improvement projects were very helpful for the City staff in explaining the short and long term need for these projects to the elected officials as well as the general public. A similar process of identifying and prioritizing stormwater CIP projects may also prove very useful for many other communities.

back to top

SANITARY AND COMBINED SYSTEM MANAGEMENT

Select this Article		Using Long‐Term Simulation for Improving a Sewer System Overflow Control Strategy Elizabeth L. Cavanaugh, Eric D. Loucks, and Steven R. Heinz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)412 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Milwaukee Metropolitan Sewerage District (MMSD) is implementing a comprehensive program to reduce the frequency and volume of overflows. Under this program, MMSD strategies have included construction of additional flow storage and conveyance facilities, increased wet weather treatment capacity and upgraded the real‐time control (RTC) in the operation of gates and diversions in the collection system. After constructing nearly one billion dollars in storage and conveyance system improvements, overflow frequencies have been reduced by more than 90 percent since 1993. Further improvements can be obtained through optimized operation of these facilities. Strategy improvements have been difficult to identify in practice because of ongoing changes to system facilities and the relative infrequency of the storm events that cause overflows. A simulation modeling tool known as MACRO has been developed to permit the analysis of MMSD storage and conveyance facilities under a fixed set of system conditions over long periods of time. Various management options can be modeled to investigate potential strategies to minimize the risk of overflows. A key policy objective is minimizing the frequency and volume of separate sewer overflows (SSO) under the constraint of avoiding discharge permit violations. This objective results in several different trade‐offs between SSO frequency and other undesirable outcomes including CSO or excessive plant flow. In this study, MACRO runs are used to determine tradeoff curves based on varying the degree of certain control inputs. These curves are demonstrated to be useful in identifying the optimal operating procedure to meet a specified set of objectives.

back to top

SEDIMENT IN URBAN WATERSHEDS: MODELING, ECOLOGICAL LINKS, AND TMDLS FOR SEDIMENT IMPAIRED SYSTEMS

Select this Article		The Use of Sediment Tracers in Watershed Processes R. Theregowda, O. Abaci, and A. N. Papanicolaou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)413 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper reports the results of soil biogeochemical analyses (e.g. organic matter, clay%, sand%, CEC, pH, etc.) performed to characterize the biogeochemical properties of soils in the Upper South Amana area, a sub‐catchment of the Clear Creek Watershed. Most of these properties are in turn used as inputs to the WEPP (Water Erosion Prediction Project) upland erosion model to predict sediment erosion rates. WEPP is a process‐based, event‐based, distributed parameter, water flow driven erosion prediction model. Climatic data and Digital Elevation Models (DEM) are also incorporated in the model along with the biogeochemical properties of the soils. The WEPP model is first calibrated and then a sensitivity analysis is performed to identify the governing parameters of upland erosion in the Upper South Amana Area. Such comparison will further strengthen the argument regarding event‐based simulations vs. continuous based simulations. The results of this study will be used for supplementary investigation of physical mechanisms of upland erosion processes.

Select this Article		Extended Analysis for Sediment Pond Design Yuan Cheng, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)414 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An example of extended analysis for sediment pond design is presented. The sediment pond is designed to trap the suspended sediment carried by surface runoff from a construction site. Extended analysis can show dynamic changes of the velocity field in a pond as well as suspended sediment distribution from the pond inlet to the outlet. Results from the analysis can be used by designers to adjust pond size and shape for more effective reduction of sediment discharge, that varies with time at the pond outlet.

Select this Article		A Process Based Erosion and Sediment Model for Construction Sites Bruce N. Wilson and Aleksey Y. Sheshukov ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)415 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sediment loads from construction sites can be a significant environmental pollutant. Models are useful tools that can be used to evaluate the effectiveness of different sediment control plans. The WATER (Watershed Assessment Tool for Environmental Risk) model has been developed specifically to simulate erosion and sediment processes at construction sites. Risk is assessed in this model from ensemble statistics obtained from many years of simulated weather conditions. The user has a choice of different modeling methods from which the most appropriate is selected based on site characteristics, availability of parameters, and expertise of the user. An important subcomponent of the WATER model is the prediction of climate conditions. This stand alone subcomponent is called the WINDS (Weather Inputs for Nonpoint Data Simulations) generator and is also briefly discussed.

back to top

SEWER AND COMBINED SYSTEM MANAGEMENT

Select this Article		Prioritization of Annual Mains Replacement Activities Using Historical Failure Data, Hydraulic Modeling, and Economic Data Joel G. Johnson, P.E., Mark Brundle, Antony Green, and Peter Tinubu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)416 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Water utility operations and engineering staff are responsible for the integrity of water distribution mains, including the development of a capital improvement program that ensures replacement and rehabilitation activities are targeted for best value. The City of Atlanta used a capital planning approach towards mains replacement activities that was developed by Advantica, Inc. using predictive condition modeling based on historical main failure data. The approach weighted this data using hydraulic modeling results to determine current levels of service for each main, targeting mains for replacement that were critical to meet Atlanta's service‐level goals, which consider social, economic, and environmental factors. The predictive condition model calibrated by Advantica was based on historical pipe breakage data and the material and age of each system pipe. This condition model was built within Atlanta's GIS system using a specialized application to perform a statistical analysis of the failure data and predict future pipe failures. Atlanta also wished to consider key performance indicators from its distribution network hydraulic model and target pipes for replacement that were poor performers in providing adequate fire flows throughout the system. Atlanta's distribution network model was used to analyze each pipe in the system and determine the number of times it constrained the system in meeting required fire flow demand. Advantica used a weighted analysis to rank mains for replacement considering the condition model and the hydraulic performance indicators. A total score was derived for each pipe in the system based on the sum of the weighted values of each indicator and the pipes were ranked according to this total score. The ranked mains were then grouped into regional projects to match the City's target level of expenditure while also gaining cost efficiency by considering other utility and excavation projects and other non‐technical factors (i.e. social, economic, and environmental) affecting regional utility improvements.

Select this Article		Prioritizing Collection System Repairs with Limited Information David Sample, Ph.D., P.E. and Sean Kilpatrick, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)417 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sewer Collection systems can contribute substantial pollutant loading to receiving waters during wet weather events due to Sanitary Sewer Overflows (SSOs). The implementation of the Total Maximum Daily Load (TMDL), the National Pollutant Discharge Elimination System (NPDES) Phase I Stormwater Program and other Non Point Source (NPS) reduction programs have identified water quality issues associated with SSOs. A new program being implemented to address these issues is the Capacity, Management, Operations, and Maintenance (CMOM) program; the goal of this program is to minimize SSO events, this is accomplished by many facets of the program, including development and implementation of a system that prioritizes maintenance needs, including infiltration/inflow (I/I) investments in repairs to the collection system. This paper describes an ongoing I/I reduction project in the Morning Creek basin in the southern portion of Fulton County, (Atlanta) Georgia. This basin consists of approximately 3800 manholes and 230 kilometers of pipeline divided into 14 separate sewersheds (defined by the location of a sewer flow monitoring station). The project uses a process called the “find and fix” approach which combines engineering analysis with construction of repairs of identified defects. Defects that cause I/I are identified, and then assessed to determine the most cost‐effective investments from a flow reduction perspective. This process differs from the traditional approach to I/I reduction in that it is flexible in terms of information required for the analysis. Several tools were adapted to this project, including a Decision Support System (DSS) and a Geographic Information System (GIS)‐based hydraulic model. A DSS is used using InfoNet (Wallingford Software), the DSS assists in the integration of GIS information, asset management databases, CCTV (Closed‐Circuit Television) of sewer lines, manhole surveys and inspections, and hydraulic model information. These tools are employed in an illustration of the prioritization process; tracing the analysis of from the entire basin to evolution of specific work order for repairs.

back to top

URBAN STREAM ECOLOGY

Select this Article		Vegetative Flow Resistance: Characterization of Woody Plants for Modeling Applications Juha Järvelä ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)418 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Flow‐vegetation interaction is a complex process which causes difficulties in hydraulic modeling. The purpose of this paper is to investigate the characterization of natural woody plants, and further, the determination of flow resistance coefficients for modeling applications. Flume studies with both living and artificial plants were performed to investigate the effect of flow velocity, relative submergence, and vegetation density on flow resistance. Large differences between natural and artificial plants were found. Subsequently, a computational approach for determining flow resistance coefficients for complex woody vegetation was discussed. In the approach, woody vegetation was characterized by leaf area index (LAI), a vegetation parameter χ, and a species‐specific drag coefficient C_dχ. LAI was used to take the vegetation density into account, and the species‐specific vegetation parameter χ considered the effects of plant deformation in a flow.

Select this Article		Relationships Among Land‐Use, In‐Stream Stressors, and Biological Condition in Prince George's County, MD JoAnna L. Lessard, Mow Soung Cheng, Chris Akinbubola, James B. Stribling, and Erik W. Leppo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)419 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Changes in land use / land cover have been repeatedly shown to be strongly associated with overall ecological degradation of streams. As natural areas are developed, there is a resulting change in the hydrologic characteristics. The development activities that alter natural ecosystem structure and function are considered stressors of that ecosystem. The intermediate linkages and complex mechanisms that relate these stressors, which are produced by the landscape features (sources), have not been as well illustrated. Diagnostic analyses performed in this study illustrate linkages not only between the sources of stressors and the stressors themselves, but also between the stressors and the biological response variables (benthic macroinvertebrates and fish). Prince George's County, for the past five years, has conducted a biological monitoring program that covered every subwatershed in the County. Using the database developed by this monitoring program of more than 255 sites, stepwise multiple regression was performed. Results demonstrated that the strongest source‐stressors associations were between medium and high density residential and commercial and industrial land use as the sources, and reduced overall physical complexity of the stream habitat (i.e., decreased availability of gravel substrate, diminished cover, reduced channel sinuosity, and reduced pool variability and substrate), as the stressors. The biological response variables that had the strongest association with these stressors were the benthic macroinvertebrate and fish indexes of biotic integrity (B‐IBI and F‐IBI), the Ephemeroptera‐Plecoptera‐Trichoptera (EPT) Index, Beck's Biotic Index, % Dominant Fish Species, and % generalists, omnivores, and invertivores (%GOI). These results have been used as the basis for developing the County's Green Infrastructure Plan and the decision making tool for reviewing new development proposals. The purposes of this paper are to present the results of these findings and to recommend solutions that can enhance the likelihood of desirable biological changes. The management recommendations are to reduce, eliminate, or buffer the most likely sources causing production of the stressors.

Select this Article		Preliminary Study of Water Pollution Due to Re‐Suspension of Bed Materials Adsorbing Pollutants Yun Ding, De‐yu Zhong, and Xue‐zhong Yu ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)420 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper studies the water pollution process due to the re‐suspension of the bed materials adsorbing pollutants in alluvial rivers. In this paper, by considering the periodical migrations of the bed form as a disturbance on the bed sediment, an equation that describes the transport of the pollutants adsorbed on the bed materials in the active layer is obtained. It gives the dynamic characteristics of the temporal and spatial variation of the pollutants absorbed in sediment particles of the bed materials. The equation quantitatively reflects the factors affecting the pollution process in terms of the flow intensity, the periodical migration of bed forms, and the process of river degradation or aggregation. The water pollution attributed to the scour of the bed materials adsorbing pollutants is numerically investigated by the transport equation obtained in this paper coupled with the sediment transport equation. Simulation without considering the impact of the dynamics of the active layer of alluvial rivers is also presented in this paper. Comparison indicates that the periodical movement of the bed forms plays an essentially important role on the pollution.

Select this Article		Protocols for the Evaluating the Effects of Land‐Use Patterns and Runoff Management on Urban Streams Larry A. Roesner, Ph.D., P.E. and Christine A. Rohrer, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)421 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The design of urban runoff management facilities generally includes peak shaving for flood control, and best management practices (BMPs) for removing pollutants from the runoff. A number of scientists have concluded that the combination of these two control practices, which were developed independently of one another, is not sufficient to protect aquatic ecosystems. But these conclusions have focused solely on the bioassessment of urban streams without taking into account the design criteria used for peak flow reduction facilities and for BMPs. Previous studies at the Colorado State University Urban Water Center (CSU), have demonstrated that if the design storms for peak flow control are properly chosen and used in conjunction with the properly sized volumetric BMPs, it is possible to preserve the predevelopment peak‐flow frequency curve and to minimize geomorphic instability in an urbanizing watersheds. Current research at CSU is now focusing on the development of a protocol for data collection along urban gradients combined with mathematical modeling to determine the ecologic impacts of urban runoff resulting from different land use patterns and/or implementation of alternative runoff management technologies. This study builds upon a previous study conducted for the Water Environment Research Foundation on the Physical Effects of Wet Weather Discharges on Aquatic Habitats — Present Knowledge and Research Needs. A protocol is being developed that includes a procedure for data collection and analysis to determine how statistical characteristics of stream‐flow, i.e. “stream metrics,” change with urbanization and runoff management practices, and how these stream metrics can be used to estimate geomorphic stability and health of a stream ecologic system under alternative development and/or runoff control scenarios. This paper describes the protocol that has been developed and how it is being applied to test areas in the Raleigh, North Carolina area, using data gathered by the USGS in their Urban Gradient Studies under the NAWQA program.

back to top

URBAN STREAM HYDROLOGY

Select this Article		Effects of Catchment Modification on the Flow Frequency Curve Modeled Using the EPA‐SWMM Model J. P. Davis, M. ASCE, C. A. Rohrer, P.E., M. ASCE, and L. A. Roesner, Ph.D., P.E., F. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)422 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Urbanization often produces detrimental impacts on receiving stream ecology due to an increased volume and velocity of storm runoff. The hydrologic effects of urbanization, including: increases in bankfull events, increased flooding, increased peak flows, decreased baseflow, stream enlargement, stream incision, severe stream bank erosion, sedimentation, changes in morphology, increased instream sediment load, increased sediment transport, aesthetic degradation, degradation of designated uses, and loss of fish populations. The purpose of this study is to determine how different physical characteristics of a watershed affect the peak discharges of runoff events produced by fifty years of continuously modeled precipitation. The Runoff and Statistical Blocks of the EPA Stormwater Management Model (SWMM4.4h) and rainfall from three climatically different cities were used to generate flow frequency curves that illustrate changes in subcatchment imperviousness, slope, runoff length, and Horton infiltration parameters. Historical rainfall hyetograph information for Fort Collins, Colorado; Atlanta, Georgia; and Seattle, Washington were used to determine the effects of different rainfall patterns in three subcatchments ranging from 6 to 10 Hectares. Results indicate urbanization has the greatest impact on the peak discharge of catchment runoff and caused all flow frequency curves in all three cities modeled to shift upward. While changes in slope, runoff length, and infiltration produced no alteration in runoff magnitude and frequency for some storms (seen through the convergence of the flow frequency curves), the impact of urbanization on the frequency and magnitude of runoff events was apparent in all scenarios run. As the level of urbanization changed, some response was always visible, no matter how the three other variables were altered.

Select this Article		Simplified Detention Requirements with Watershed‐Wide Benefits Bruce M. McEnroe and William J. Heatherman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)423 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The City of Overland Park, Kansas, has required stormwater detention for new developments in watersheds with known flooding problems since the early 1980s. Although technically sound, the City's current detention requirements are rather complicated and time‐consuming to apply and administer. Simplified detention requirements that would streamline the design process and reduce the administrative workload were desired. We explored a simplified method that used standardized release rates in 100‐year storms. Simplified, representative watersheds ranging in size from 200 acres to 40 mi² were tested for detention control using standardized hydrologic methods and detention basin designs. The first set of tests focused on the maximum 100‐year release rate that would prevent an increase in nuisance flooding directly downstream of a 10‐acre development. We found that a 100‐year release rate of 3.0 cfs per acre would provide reasonable assurance of no increase in the 10‐year discharge from the development site. The objective of the second set of tests was to find a release rate that would also prevent increases in Q10 and Q100 at a problem site with a drainage area of 200 acres as the watershed is developed. Because the impact of a development on flooding at a downstream problem site depends on the location of the development within the larger watershed, multiple development patterns were tested. We found that a 100‐year release rate of 3.0 cfs per acre for new developments would prevent increases in Q100 and Q10 at the 200‐acre point in nearly all cases. Additional tests focused on the downstream impacts of in‐fill development and redevelopment projects. We found that higher release rates are acceptable for redevelopment projects. The effectiveness of development‐scale detention for larger‐scale flooding problems was investigated on hypothetical watersheds with drainage areas up to 40 mi². We found that the downstream benefits of on‐site detention diminish with increasing watershed size. Development‐scale detention does not prevent an increase in flooding at a problem site with a drainage area over a few square miles. However, it does mitigate the increase in discharge.

Select this Article		Flow Trend Analysis in the Rouge River Watershed and the Effect of Temporal Resolution on Trend Detection C. A. Rohrer, P.E., M. ASCE and C. L. Hughes, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)424 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Rouge Project has monitored discharge at 13 continuous flow gauging stations serving drainage areas varying from nine to 410 square miles for the past 11 years as a means of evaluating existing conditions and tracking progress. This study evaluates the flow regime of the Rouge Watershed including the analysis of a decade or more of data, and status with regard to ecological targets. The temporal resolution of in‐stream flow data required to establish long‐term trends is also investigated by comparing flow exceedence frequency curves developed using 15‐minute, hourly average, and daily average flow data and the Mann‐Kendall analysis for trend at varying exceedence classes. Trend analysis of flow frequencies indicates that flow values have decreased, or have remained the same over the period of record examined for each flow monitoring station along the Main, Upper, and Middle Rouge Rivers. A strong trend of increasing flows was observed in the Lower Rouge River for flows in the low to mid‐range, primarily due to increased wastewater treatment plant discharges. The direction of trends predicted by flows measured at a 15‐minute, hourly‐average, and daily average time scale did not vary, although trend strength varied significantly. Fewer differences in trend strength were observed between 15‐minute and hourly‐average data than between 15‐minute and daily‐average data, indicating that hourly data are adequate for trend analysis. The overall number of ecological flow targets that were met did not increase at nine Rouge flow monitoring stations between the time periods of 1994–1999 and 2000–2005. Summer improvements of peak flows were observed at one station along the Lower Rouge River. Flows fell from within the acceptable tolerance range to below lower bounds at two stations, indicating a decrease in baseflow at those stations.

Select this Article		Quantifying Urban‐Induced Flow Regime Alteration and Evaluating Mitigation Alternatives Using Mathematical Models and Hydrologic Metrics J. L. Egderly, L. A. Roesner, C. A. Rohrer, and J. A. Gironás ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)425 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract There is growing interest in identifying mechanistic linkages between watershed urbanization and associated geomorphic and ecological consequences in urban streams. Recognizing watershed hydrology as a key determinant in the structuring of ecological systems, an increasing number of researchers are attempting to characterize the ecologically important aspects of long‐term stream flow patterns using statistically‐based hydrologic metrics. Complimentary to such research efforts is determination of the efficacy of stormwater controls for mitigating undesirable effects in streams caused by urbanization. This study integrates a modeling approach, commonly used for designing runoff controls, with a flow regime approach aimed at quantifying ecologically‐important aspects of flow regime. Hydrologic metrics from previous studies were tailored to better suit the small‐scale, urban context. MATLAB© was used to calculate the select set of metrics from 48‐year, 15‐minute continuous flow time series, generated by EPA SWMM4.4h. Potential climatic influences on metric behavior were examined by comparing metric behavior obtained by using rainfall from Fort Collins, CO and Atlanta, GA. The influence of temporal resolution of flow data on metric values and its implications for the metric selection process were also investigated.

back to top

URBAN WATERSHED MANAGEMENT KEYNOTE PRESENTATIONS

Select this Article		Integrated Watershed Management Robert Pitt ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)426 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Before stormwater control programs can be selected and evaluated, it is necessary to understand the problems in local receiving waters. The lists below give typical receiving water problems, both those associated with the long‐term accumulation of pollutants and those caused by short‐term (event‐related) problems. Long‐term problems associated with accumulations of pollutants in waterbodies include: 1) Sedimentation in stormwater conveyance systems and in receiving waters, 2) Nuisance algal growths from nutrient discharges, and 3) Inedible fish, undrinkable water, and shifts to less sensitive aquatic organisms caused by toxic heavy metals and organics (such as with contaminated sediment). Short‐term problems associated with high pollutant concentrations or frequent high flows (event related) include: 1) Swimming beach closures from potentially pathogenic microorganisms, 2) Water quality violations, especially for bacteria and heavy metals, 3) Property damage from increased flooding and drainage system failures, and 4) Habitat destruction caused by frequent high flow rates, although actual stream bed enlargement may take place over several years (bed scour, bank erosion, flushing of organisms downstream, etc.). Many of these problems have been commonly found in urban receiving waters in many areas of the U.S. Because these problems are so diverse, a wide variety of individual stormwater controls usually must be used together to form a comprehensive wet weather management strategy, and in conjunction with suitable wastewater collection and treatment methods. The integration of water use considerations also can be an important tool in an integrated watersheds management program. Unfortunately, combinations of controls are difficult to analyze either using most available stormwater models or directly from the results of monitoring activities. These difficulties will require new modeling techniques that will enable an effective evaluation of a wide variety of control practices and land uses that may affect the entire suite of receiving water problems, while at the same time the design and implementation of these practices must meet the over‐riding storm drainage objective of flood control.

Select this Article		The Great Works of UWRRC Jonathan E. Jones, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)427 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Over the past four decades, members of the American Society of Civil Engineers (ASCE) Urban Water Resources Research Council have made extraordinary contributions to the field of urban water resources planning, design, and management. Historically, the Council has been comprised of many leading water resources engineers and scientists, and they have collaborated to prepare over 150 reports, technical memoranda, conference proceedings, and other documents on wide‐ranging subjects. The purpose of this book is to republish selected great works of the UWRRC. Many of the UWRRC's publications are as timely and provocative today as when they were first published. Indeed, readers will be struck by the foresight and perspectives of Council members from decades ago on such subjects as: drainage and flood control; stormwater quality management; water supply planning; risk assessment; public involvement and participation, and the role of the water engineer in society, to name only a few. The founding members of the Council include: (1) Stifel W. Jens, (2) D. Earl Jones, Jr., (3) J.C. Geyer, (4) Carl F. Izzard, and (5) William C. Ackermann. The original Council Program Director was Murray B. McPherson and the Deputy Program Director was L. Scott Tucker. All water resources practitioners owe a debt of gratitude to these leaders and visionaries.

back to top

URBAN WATERSHED MODELING I

Select this Article		Improvement of the EXTRAN Block in Storm Water Management Model (SWMM4.4h) Daeryong Park, Jorge Gironás, Larry A. Roesner, Ph.D., P.E., F. ASCE, Martin A. Farber, P.E., and Sukhwan Jang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)428 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The EPA Storm Water Management Model (SWMM) is a dynamic rainfall‐runoff model for single‐event or long term simulation. The EXTRAN block of this model can simulate storm sewer systems. Under flood condition, if there is not a surface channel, the current EXTRAN block loses water to the streets and it does not return to the storm sewer system. In reality, flooded water may actually return to the storm sewer system again through nearby junctions or manholes. While it is possible to specify a system of surface channels to route surface flooding, EXTRAN limits inflows from the surface back into the system, based only on the flow capacity available in the storm sewer system. It does not take into account that the rate of return to the system may be restricted by the street inlet through which the water must pass. Therefore, the existing EXTRAN block has a problem with returning flow to the system, and it is difficult to characterize the actual behavior of the storm sewer system under this type of condition. The City of Sacramento addressed this problem and made extensive modifications to the SWMM version 2.2 so that inflow back into the sewer system at a junction is restricted to the smaller of (1) available flow capacity of sewer system or (2) inlet capacity at junction. This algorithm works well in the Sacramento SWMM (S‐SWMM) model, but the EXTRAN block of this model is a version older than the current EXTRAN block of the SWMM 4.4h model. Thus, it was decided to modify the EXTRAN block of the SWMM 4.4h to incorporate the inflow modifications in the S‐SWMM model. This study will mainly add the subroutine OVFLOW of the EXTRAN block of the S‐SWMM model to the EXTRAN block of the SWMM4.4h model since it models street flow. The purpose of this study is to integrate the FORTRAN source code of the EXTRAN block from S‐SWMM model to SWMM 4.4h model. The revised EXTRAN block is tested on an experimental sewer system and is compared to SWMM 4.4h and S‐SWMM. In addition, we investigate how the street flow contributes to inflow and direct rainfall runoff in S‐SWMM and SWMM 4.4h. Simulation results generated by the models are expected to show the inlet restriction effect and the available flow capacity of the sewer system. It is proved that the S‐SWMM 4.4h can embody the real urban storm water phenomenon more closely than the S‐SWMM and SWMM4.4h.

Select this Article		Simulation of Infiltration and Surface Runoff — A Windows‐Based Hydrologic Modeling System HYDROL‐INF Xuefeng Chu, M. ASCE and Miguel A. Mariño, Hon. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)429 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Simulation of infiltration and surface runoff, two closely‐correlated processes during rainfall events (wet time periods), is critical to water quantity and quality studies for both surface and subsurface systems. Partitioning rainfall into these two primary water pathways is fundamental to any hydrologic modeling. In a continuous hydrologic model, it is also essential to simulate drainage and redistribution of soil water between two rainfall events (dry time period). A new algorithm is proposed to simulate infiltration into a layered soil profile of arbitrary initial water distributions under unsteady rainfall and the resultant surface runoff. Two distinct periods, pre‐ponding and post‐ponding, are taken into account. The model tracks the movement of the wetting front along the soil profile, checks the ponding status, and handles the shift between ponding and non‐ponding conditions. The model is further extended to complex rainfall patterns that include both wet time periods with unsteady rainfall and dry time periods without rainfall by incorporating a compartmental model that accounts for drainage and redistribution in the soil profile. Furthermore, a Windows‐based modeling system, HYDROL‐INF, is developed, which integrates pre‐processing of data, model run, and post‐processing in a user‐friendly Windows interface. To facilitate parameter estimation, a parameter database is developed and incorporated. Additionally, the HYDROL‐INF system also includes some useful hydrologic tools/calculators that can be used in applied hydrologic investigations.

Select this Article		An Integrated Approach to Water Quality Assessment in Support of a Long‐Term Control Plan M. E. Hulley, G. Zukovs, P. Gray, and M. Umberg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)430 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Metropolitan Sewer District of Greater Cincinnati, MSDGC, is in the process of developing a comprehensive Long‐Term Control Plan, LTCP, addressing combined and sanitary (CSO and SSO) overflows. In support of this plan, an integrated suite of numerical tools was developed to facilitate comparative assessment of alternative solutions. In particular, the numerical tools provided the necessary linkages between reduced CSO and SSO loadings and in‐stream water quality benefits. A review of historical monitoring information, in combination with the results of a recent monitoring program, has demonstrated that the sole pollutant of concern is E. coli. Consequently, the scope of the water quality evaluation focused on E. coli, while benefits were defined in terms of reduced risks to human health during the recreation season and increased opportunities for water based recreation. A watershed‐approach was followed and benefits were assessed on scales ranging from first‐order stream streams, with drainage areas of 50 square miles or less, to the Ohio River.

Select this Article		The Application of Radar Rainfall Data to Collection System Analysis George Zukovs, P.Eng., Christine Hill, P.Eng., Daniel Jobin, P.Eng., and Tracey McLean ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)431 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The design of major collection system elements such as trunk sewers and large pumping facilities must realistically account for sanitary inputs as well as possible wet weather flows. The wet weather component often originates in the older portions of existing communities that may be served by the new infrastructure. The designer's challenge is to predict peak flows for situations far in the future as well as embracing a wide variety of local collection systems located across a large regional sewershed. The Region of York owns and operates the major sanitary sewer system within its jurisdiction named the York Durham Sewage System or YDSS. Wastewater collected through the YDSS is conveyed to neighbouring Durham Region for treatment at the Duffin Creek WWTP. The YDSS system currently has a service area of 242 km² and a planned future service area of 448 km². Historically, the Region has evaluated the available capacity in the YDSS using a hydrologic‐hydraulic capacity model. The model incorporates dry weather flow generation based on population and land use and wet weather modeling transforming design rainfall events into wet weather sewer flows. A peer review of the YDSS capacity model identified that previous capacity assessments were completed using the assumption of uniform rainfall across the entire service area of the Region. The use of this assumption generally resulted in over prediction of total peak flows. Accordingly, it was recommended that the Region undertake a detailed spatial rainfall analysis to identify appropriate areal rainfall reduction factors for the YDSS. The following paper presents the results of a study conducted on behalf of the Region of York to develop areal reduction factors that may be applied to wet weather design flow predictions.

back to top

URBAN WATERSHED MODELING II

Select this Article		Operation of the Trinity River/Fort Worth Central City Flood Management System Eric D. Loucks and Lisa M. Stahr ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)432 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Tarrant Regional Water District (TRWD), in cooperation with the US Army Corps of Engineers (USACE), the City of Fort Worth, and Tarrant County, is currently in the planning stages of the Fort Worth Central City (FWCC) Project, a plan to implement improvements along the Trinity River to reduce flooding and provide recreational and other quality‐of‐life enhancements in the area adjacent to downtown Fort Worth. The project involves the construction of a bypass channel to divert flood flows away from downtown Fort Worth, a dam and three flood isolation gates, among other associated improvements. In order to commence final design of the channel improvements, a significant, detailed hydraulic modeling effort was necessary to confirm the feasibility of the plan as well as to determine the operating characteristics. Flood flows will be diverted to the bypass channel and flood isolation gates will be designed to limit the flows in the existing channel to low flows. In addition, navigable water levels will be maintained through the existing channel, the bypass channel and along Marine Creek (a tributary to the Trinity River). This paper describes how a dynamic hydraulic model was employed to determine and verify the operating procedures for the proposed improvements.

Select this Article		Evaluation of Bacteria Impacts on Beaches in Milwaukee: The Bacteria Source, Transport and Fate Study Kimberly A. Oriel, Andrew J. Thuman, Christopher Magruder, and Sandra L. McLellan, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)433 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Milwaukee Harbor Estuary Modeling Bacteria Source, Transport and Fate (BSTF) Study was launched in 2003 as part of the development of an integrated water quality modeling framework for addressing the water quality issues in the Greater Milwaukee area. A hydrodynamic model and a water quality model were constructed to work together with historical data collected by Milwaukee Metropolitan Sewerage District and the Great Lakes WATER Institute at the University of Wisconsin — Milwaukee. The models were developed to better define the movement and survival of bacteria in Milwaukee's harbor estuary and near shore area of Lake Michigan. In addition, the BSTF Study includes an investigation of possible bacteria sources through the use of genetic markers and antibiotic resistance techniques. Water quality issues, especially those that pertain to the recreational beach areas of Lake Michigan, have received a great deal of attention in Milwaukee over the last few years. There is public perception that beach closures are correlated to combined sewer overflow (CSO) and separate sewer overflow (SSO) events. It has been found that while CSO/SSO events in recent years have occurred only a few times per year, beaches may be closed for a significant part of the recreational season. The BSTF modeling shows that rainfall events with CSOs do not impact the bacteria concentrations of the near shore area more significantly than rainfall events without CSOs. The BSTF Study is on‐going and will provide not only a decision‐support tool, but also a means to inform the public about beach water quality.

Select this Article		Optimized Vegetation Buffer Strips Design for Integrated Management of Goodwin Creek Watershed in Mississippi Honghai Qi, Mustafa S. Altinakar, Dalmo A. Vieira, and Bahram Alidaee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)434 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A principal contributor to soil erosion and non‐point source pollution, agricultural activities have a major influence on the environmental quality of a watershed. Impact of agricultural activities on the quality of water resources can be minimized by implementing suitable Best Management Practices (BMPs). The selection and design of these BMPs must be carried out by optimizing both technical and economical considerations. For example, a Vegetation Buffer Strip (VBS), one of the commonly used off‐field structural BMPs, can significantly improve the water quality when it is designed and placed correctly. On the other hand, a VBS occupies a portion of the agricultural land that could have been used for crop production, and implementation/maintenance costs are involved. Currently, VBSs are designed (location, plant type, and width) based on field study results, and do not involve a science‐based approach to ensure their efficiency under particular regional, climatic, geological and economical conditions. The present study proposes a new approach which integrates computational modeling of watershed processes, fluvial processes in the drainage network and modern heuristic optimization techniques to design cost effective VBSs. The watershed model AnnAGNPS and the channel network model CCHE1D are linked together to simulate the sediment/pollutant transport processes. Based on the computational results, a multi‐objective function is set up to minimize soil losses, nutrient concentrations, and total costs associated with installation and maintenance of VBS, while the production profits from agriculture are maximized. The iterative optimization algorithm uses adaptive Tabu search heuristic to flip VBS design parameters. USDA's Goodwin Creek experimental watershed located in Northern Mississippi is used to demonstrate the capabilities of the proposed approach. The results show that the optimized design of VBS using an integrated approach at the watershed level can provide efficient and cost‐effective conservation of the environmental quality by taking into account also productivity and profitability.

back to top

WATER QUALITY AND QUANTITY EFFECTIVENESS OF BMP TECHNOLOGIES

Select this Article		Developing a Comparative Tool for Both Conventional and Green Stormwater Management Techniques D. A. Hollander, B. Eyring, P.E., and A. R. Schmidt, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)435 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes a comparative tool that was developed to provide useful, technical information on the benefits of green drainage‐management techniques by comparing them with the benefits of conventional techniques. This tool was developed to provide quantitative information for both residents and municipalities on the benefits of green techniques, in terms of runoff and discharge levels, detention requirements, and economics on both the lot and 40‐acre area scales.

Select this Article		Q2 — Designing for the Quality as Well as the Quantity of Water: A Review of the Kansas City Manual of Best Management Practices J. W. Henson and T. A. Jacobs ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)436 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Kansas City metropolitan area chapter of the American Public Works Association (APWA) adopted a new Best Management Practices Manual for Stormwater Management (BMP manual) in November 2003 as a reference document. The chapter did not adopt the BMP manual as a standard because the membership believed many communities were not ready to fully implement BMP programs. Since that time, a few communities in the KC metro have adopted the BMP manual as a design standard for new development. The BMP manual uses TR‐55 methodology for calculating changes in volumes of runoff and peak rates as its basis. The changes in volume and rate of runoff are related to a required level of service to be provided by BMPs to minimize impacts of development. BMP level of service is defined by the overall percent removal provided by each type of BMP and its ability to detain or infiltrate runoff. This methodology was developed to allow design engineers flexibility in choosing the BMPs that best fit the site being developed based on common calculations that most engineers understand and have completed. By incorporating the ability of a BMP to detain or infiltrate runoff in the assigned level of service, the BMP manual places a high priority on those BMPs that minimize volume of runoff. The manual steers the design engineer towards maintaining natural areas and minimizing imperviousness to minimize impacts. The City of Lenexa conducted a series of evaluations where site designs were modified to incorporate the requirements of the BMP manual. Residential and commercial sites were chosen for the evaluation. This was an office exercise to show the community leaders that the BMP manual would not increase the costs of site development and that its methodology was practical and achieved the goal of minimizing impacts of new development. Several new developments have been designed using the BMP manual. The lessons learned and an assessment of the BMP manual's effectiveness will be provided.

Select this Article		A Cohesive Approach for the Implementation of the Comprehensive Everglades Restoration Plan Scott L. Knight, James P. Heaney, and Daniel L. Reisinger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)437 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Comprehensive Everglades Restoration Plan (CERP) is a strategy to improve the function and quality of the South Florida ecosystem. This plan is being developed as a partnership between the US Army Corps of Engineers (USACE) and the South Florida Water Management District (SFWMD). Because of the scale of the CERP, the SFWMD elected to create Acceler8 to expedite the funding and construction of eight CERP projects. One of the projects selected for design and construction under Acceler8 is the Everglades Agricultural Area Storage Reservoir (EAASR) — Phase 1. Because of the planning and funding processes for the USACE and the SFWMD differences arise in the development of alternatives and selection of a preferred alternative. This paper addresses the issues that occur, and suggests a method to develop a cohesive approach for development of the EAASR.

Select this Article		Finding the Best Comparable Dataset for Estimating Parameters for a Water Quality Model Daniel L. Reisinger, James P. Heaney, and Scott L. Knight ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)438 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this study is to estimate the changes in total phosphorus (TP) concentrations that can be expected in a large reservoir that is to be constructed as part of the Everglades restoration. This study describes how the best comparable calibration dataset was selected in order to find parameter estimates to model the expected performance of the new reservoir. A database of 18 Florida lakes and a reservoir were used to determine systems comparable to the possible TP kinetics of the proposed Everglades Agricultural Area Storage Reservoir (EAASR). Crescent Lake and Lake Istokpoga were found to be the closest comparables. Assessment of the two lake datasets showed that the Lake Istokpoga historical data were preferable. The mass balance terms, period of record, and averaging period were determined for use in TP settling rate calibration. Mass balance terms were categorized as inflow, outflow and storage. The period of record to be analyzed was selected based on having a minimum amount of trends in input and output water quality. A monthly averaging period for water quantity and quality was chosen for the period of record based on the quality of the mass balance data and preliminary estimates of hydraulic residence times for the EAASR. Selected results of this procedure are presented for this application.

back to top

INTEGRATED WATER RESOURCES MANAGEMENT I

Select this Article		Options for a Decision Support System on the Central Platte River Basin Donald Frevert, Mike Kube, Amy Lieb, Jeff Rieker, and Duane Stroup ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)439 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Management of water resources in the central Platte River basin of Nebraska incorporates both ground water and surface water. Development of a decision support system is being contemplated by state and federal governmental agencies and by a number of local stakeholders. Requirements and priorities for the decision support system vary with the perspectives of the different entities — with some focusing on short term operational management on a daily or hourly time step and others focusing on larger time increments and longer range priorities. Water quality and ground water — surface water interaction will also be key issues which the decision support system will need to address. A detailed evaluation of a number of river basin models was undertaken by a team of modeling specialists from the Bureau of Reclamation, the Nebraska Department of Water Resources and several prominent stakeholder groups. Results of this analysis are presented and discussed. Future work will focus on identifying necessary data collection and analysis, selecting and implementing a river basin model suitable for use on the central Platte River system and, ultimately, formulating linkages with ground water and water quality models which can meet the requirements of the participants in this study.

Select this Article		Integration of Water Quantity and Water Quality Modeling on the Truckee River J. D. Rieker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)440 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A water quantity model/decision support system is currently being developed for the Truckee River to produce regulated streamflow forecasts, as well as implement proposed changes to basin operating policy. Existing Truckee Basin water quality models are being linked to the model for the purposes of enhancing long‐term planning capability and for providing near‐term decision support in the interests of improved river water quality. This paper presents the models and their linkage mechanism, as well as the difficulties encountered with the linkage of two models which use differing database systems. A summary is also presented of the challenges of providing sufficient input data to the integrated model system.

back to top

INTEGRATED WATER RESOURCES MANAGEMENT II

Select this Article		Changing Tactics for Managing Water in Alberta — The Water for Life Strategy and Challenges in Its Implementation H. Bjornlund, L. Nicol, and K. K. Klein ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)441 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Since irrigation is by far the dominant water user in Alberta, the participation of that sector will be critical to the successful implementation of the province's long‐term water strategy, entitled Water for Life: Alberta's Strategy for Sustainability. This study asked leading members of the irrigation districts to provide their views on the reaction of irrigators in their district to the strategy. Results show that irrigators feel conservation has become a critical issue and that water for environmental purposes is considered one of the greatest threats to irrigation water availability. Irrigators believed that the strategy's 30 percent efficiency and productivity target is beyond reach. Some gains may be possible but the approach and extent will vary by irrigation district because of differences in on‐farm irrigation efficiencies, conveyance system efficiencies, water availability, and crop production factors. Ultimately, the majority of respondents believed efficiency and productivity can be improved but in incremental amounts based on a voluntary approach.

Select this Article		U.S. Bureau of Reclamation Use of CALSIM: A Generalized Model for River System Analysis Nancy L. Parker ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)442 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract CALSIM is a general‐purpose river system modeling framework developed by the California Department of Water Resources for the planning and management of the State Water Project and the federal Central Valley Project. A river system is portrayed as a schematic network of nodes and links that represent storage and flow. Physical and operational constraints are specified with a simple scripting language. A linear programming / mixed integer linear programming solver is used to define the optimal distribution of water given user‐defined priorities or weights. Although developed for the stated purpose, the modeling software is highly generic and can be applied to other water resources systems. In addition to its use for the Central Valley Project, the U.S. Bureau of Reclamation has developed applications for Klamath Project planning modeling, Klamath River hydropower relicensing hydrology, and mass balance checks on modeling of the Truckee Carson Project. This paper will present the CALSIM model and the flexibility that makes it a valuable river system analysis tool for Reclamation.

back to top

MODELING OF HYDROLOGIC PROCESSES I

Select this Article		The Effect of Assumptions on Unknown Parameter Values in Forecasting Reliability of Meeting Effluent Limits Troy A. Doby, Ishwar Devkota, and Raymond Smith ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)443 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Forecasting tools exist for regulatory agencies to predict the reliability in meeting effluent limits or total maximum daily loads (TMDLs) from point sources discharging to water bodies covered under section 303(d) of the Clean Water Act. Performing 2‐D Monte Carlo simulations with these tools requires inputs of known (e.g., flow, temperature, influent concentrations) and unknown parameter values (e.g., autotrophic and heterotrophic growth and decay rates) and distributions. This paper examines the effects of assumptions about distributions, coefficients of variation, and parameter correlations on reliability results with several examples.

Select this Article		Digital Floodplain Mapping and an Analysis of Errors Involved Christopher S. Hamblen, David T. Soong, M. ASCE, and Ximing Cai, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)444 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Mapping floodplain boundaries using geographical information system (GIS) and digital elevation models (DEMs) was completed in a recent study. However convenient this method may appear at first, the resulting maps potentially can have unaccounted errors. Mapping the floodplain using GIS is faster than mapping manually, and digital mapping is expected to be more common in the future. When mapping is done manually, the experience and judgment of the engineer or geographer completing the mapping and the contour resolution of the surface topography are critical in determining the flood‐plain and floodway boundaries between cross sections. When mapping is done digitally, discrepancies can result from the use of the computing algorithm and digital topographic datasets. Understanding the possible sources of error and how the error accumulates through these processes is necessary for the validation of automated digital mapping. This study will evaluate the procedure of floodplain mapping using GIS and a 3 m by 3 m resolution DEM with a focus on the accumulated errors involved in the process. Within the GIS environment of this mapping method, the procedural steps of most interest, initially, include: (1) the accurate spatial representation of the stream centerline and cross sections, (2) properly using a triangulated irregular network (TIN) model for the flood elevations of the studied cross sections, the interpolated elevations between them and the extrapolated flood elevations beyond the cross sections, and (3) the comparison of the flood elevation TIN with the ground elevation DEM, from which the appropriate inundation boundaries are delineated. The study area involved is of relatively low topographic relief; thereby, making it representative of common suburban development and a prime setting for the need of accurately mapped floodplains. This paper emphasizes the impacts of integrating supplemental digital terrain data between cross sections on floodplain delineation.

back to top

MODELING OF HYDROLOGIC PROCESSES II

Select this Article		Optimal Load Reductions for Beargrass Creek Watershed in Louisville, Kentucky Mohammad Tufail, P.E. and Lindell E. Ormsbee, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)445 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the development of an optimal biochemical oxygen demand (BOD) load model for the Beargrass Creek watershed in Louisville, Kentucky. A conceptual, macro‐level BOD load model is first developed based on the steady state Streeter‐Phelps equations for dissolved oxygen deficit for the three forks of the watershed. The model is used to compute the effective total ultimate BOD concentration for the stream system based on observed dissolved oxygen deficits and stream flows measured in the field. A mass balance of flows and corresponding BOD concentrations is performed to compute the corresponding loads at the junction points of the streams. The computed loads are disaggregated into three distinct types namely, point source, non‐point source, and an unknown source attributed to other suspect sources of pollution. The BOD loading model for the watershed is used as a simulation model in a disaggregated nonlinear constrained optimization framework to obtain optimal load reductions for all three types of pollution sources for the stream system. The optimization framework uses two different types of optimization algorithms namely genetic algorithms and the box complex method of constrained optimization. The optimization framework can serve as a useful management tool for watershed decision makers to formulate and evaluate different management strategies leading to effective capital improvement projects for the watershed. Such a framework can be effectively used to determine total maximum daily load (TMDL) for streams that are impaired for low dissolved oxygen and/or nutrient enrichment.

Select this Article		Assessing the Impact of Loading Rate Uncertainties in TMDL Allocations Alex Foraste, Teresa B. Culver, and Imtiaz Taher ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)446 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract To account for uncertainty in the form of variability and incomplete knowledge in Total Maximum Daily Load (TMDL) studies, a Margin of Safety (MOS) is introduced, typically chosen arbitrarily to be 5%. This study characterizes significant uncertainties present in loading rates by using multiple scenarios that each act as real potential loads to the watershed. Loading rates are generated from specified parameter spaces using the Latin Hypercube Sampling technique, and sample distributions are chosen based on various published loading rates and the likelihood that particular loads would more closely represent loads applied to the watershed. The multiple loading rate scenarios, coupled with the multiple water quality and hydrologic parameter sets are then simulated with the watershed model, HSPF. Acceptance criteria are then applied to assess the likelihood of a particular parameter/load set to act as a real simulator of the watershed. A robust genetic algorithm model linked with a response matrix, is then used to optimize TMDL allocations and predict the reliability of compliance associated with each allocation scenario. This methodology is applied to fecal coliform load allocations in the Moore's Creek Watershed in Virginia. The results are compared to a similar study that assumed loading rates to be deterministic, allowing for the assessment of the impact of uncertainty in loading rates.

back to top

NUTRIENT MANAGEMENT

Select this Article		Lake Tohopekaliga Pollutant Modeling Study for Kissimmee, Florida Gordon England, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)447 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Over the years, there have been a number of hydraulic and hydrologic studies of the Mill Slough and East City Ditch drainage basins of Lake Tohopekaliga (Lake Toho) for the City of Kissimmee (City), Florida. These studies were highly detailed analyses performed to address a number of flooding and water quality issues within these basins. Specific recommendations for projects were made in these reports for improvements in the watersheds to alleviate identified problems. With the growing certainty of TMDLs being set by DEP, the City engaged Berryman & Henigar (BHI) to undertake a stormwater pollutant loading study, not a hydrologic or hydraulic analysis, to identify projects which could improve water quality discharges in the Mill Sough and East City Ditch basins. This report summarizes the findings of the pollutant modeling and investigates alternative BMPs in the Mill Slough and East City Ditch watersheds.

Select this Article		A Watershed Nutrient Management Model: System Dynamics and Transport Rates Approach T. Kato, M. Y. J. Purwanto, and B. I. Setiawan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)448 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract A watershed nutrient management model was developed using a combination of system dynamics (SD) and nutrient flow (NF) models to assist decision makers and stakeholders with watershed management planning for the conservation of water resources and rural development. The SD model simulates changes in socioeconomic factors such as population, land use, and economic indices; the NF model calculates in‐stream nutrient loads by using nutrient transport rates, population, and land use area; the latter two are outputs of the SD model. These models were developed and calibrated for the Cianjur watershed located in West Java, Indonesia. Rapid changes in the population and land use in this region have caused associated environmental problems and have adversely affected surface water quality. The maintenance of a balance between rural environment conservation and development is an important concern. The SD model comprises six sectors (population, land use, industrial capital, agricultural capital, water resources, and water quality). Elements used in the model were selected based on literature reviews and field investigations, and then the causal loops were created. After the SD model was calibrated manually for the period 1988 to 2000, the relative errors between the historical and calculated values were 2.6% for the total population, 13.2% for the area of irrigated paddy fields, and 6.4% for Gross Regional Domestic Production. The results of a sensitivity analysis were found to correlate well with the historical data. In constructing the NF model, the nutrient loads in surface water were estimated using transport rates that were calculated using an exponential equation based on the distances from the pollutant source to the nearest waterbody and to the mouth of that waterbody. The model was calibrated using measurement data collected during field investigations in 2003 and 2004. The locations of pollutant sources (residential areas and paddy fields), and the distances from each source to the nearest waterbody were determined using a geographical information system (GIS). The model simulated the in‐stream nutrients reasonably well. Finally, using the models developed, scenario analyses were conducted to demonstrate the functionality of the models.

Select this Article		Modeling Phosphorus in the Appoquinimink Watershed with AGNPS William F. Ritter and Scott C. Hoffman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)449 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Portions of the Appoquinimink River in New Castle County, Delaware have been declared in danger of eutrophication by the Delaware Department of Natural Resources and Environmental Control due to high phosphorus levels. The Appoquinimink watershed is approximately 12,400 hectares and is comprised primarily of agricultural lands interspersed with woodlands and rural communities and development. Previous research efforts resulted in the successful implementation of many Best Management Practices (BMPs); however, reduction of soluble P loads into surface waters remains a problem. The AGNPS model was used to model additional BMPs specifically targeting soluble P load reductions. BMPs included land use changes, adjustments of fertilization levels and application methods. Following a sensitivity analysis and calibration of the model, BMPs were tested using both growing and dormant season data sets for 1 year, 2 year and 10 year storm events. The most successful BMP was reduction of fertilization levels. Other BMPs were not found to have as great of significant effects.

Select this Article		Modeling Nutrient Dynamics in Watersheds and Streams Dalmo A. Vieira and Sam S. Y. Wang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)450 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Stream water quality is dependent on a number of complex and highly variable pollutant‐generating processes that occur in the upland and riparian zones of a watershed. A combination of watershed and channel models is used to determine the response of stream water quality to land use management activities that affect the supply of sediment and nutrients to channels. The models are integrated using terrain analysis and GIS technology, where data processing algorithms define a conceptual description of the drainage network and the corresponding subcatchments to be used by all modeling components. The CCHE1D one‐dimensional channel network model is used to compute unsteady flows and the transport and fate of nutrients through the channels of the watershed. The model accounts for the biogeochemical transformation processes that determine nutrient concentrations, in particular the simulation of the aquatic cycles of nitrogen and phosphorus compounds. The watershed model AGNPS is used to simulate the hydrologic processes and to compute the sediment and nutrient loads that reach the channels. The CCHE1D's water quality module is initially validated using data on BOD and nitrogen compounds from primarily point‐sources, measured in the Chattahoochee River. The model integration concept is demonstrated through an application to the Goodwin Creek watershed, in north Mississippi. The integrated model is used to evaluate the system's response to hypothetical land use changes, which represent possible management scenarios used to control the supply of nutrients to the streams.

back to top

WATERSHED MANAGEMENT FOR WATERSHED PROTECTION

Select this Article		Linking Species Changes to Watershed Modification: A Long‐Term Analysis Using Fish Communities Jian‐Ping Suen, A. Catherine Marcinkevage, and Edwin E. Herricks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)451 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Recent work in river restoration and water resources management requires an expansion in scope to address the effects of watershed impairment. However, comprehensive investigations at watershed scales are made difficult by the limitations of existing data sets, which are often collected for analysis at much smaller scales. This is especially true of ecological and biological data that may be collected infrequently and for reach oriented studies. This research developed a protocol for assessing the changes in aquatic communities at the watershed scale. The first step in this protocol assembles biological assessment and monitoring data. The biological data is then used with an autecology matrix that provides opportunities for analysis of habitat, water quality, and other environmental factors that are species based. We have used this protocol to examine biological assessment data collected over two decades in the Kishwaukee River, Illinois. The protocol has provided a method to identify the effects of watershed modification as well as likely causes of existing conditions. This technique provides an improved understanding of historical influences on fish community structure by using a process‐based assessment of historical data that integrates the state and condition of a biological community with likely environmental controls.

Select this Article		Application of the Community‐Based Watershed Management Planning Process to Preserve Cunningham Lake J. Farnsworth and P. Slaven ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)452 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The Community‐Based Watershed Management Plan (CBWMP) for Glenn Cunningham Lake comes at a crucial moment in the reservoir's life. Experience with other Omaha Metro area reservoirs indicates that although significant land treatment in the reservoir's agricultural watershed translates to borderline acceptable water quality, significant watershed development will result in lake degradation and loss of beneficial uses. The potential for degradation was a focal point in the management planning effort with project stakeholders choosing to adopt an aggressive protection plan designed to maintain and enhance reservoir quality throughout watershed development. The project sponsors understand that development of a relevant and implementable management plan requires the formation of a broad‐based coalition of public, private, and governmental stakeholders. To this end, the planning process was guided by a Watershed Advisory Council (WAC) comprised of watershed farm owners/operators, acreage owners, reservoir users, and concerned citizens. Additionally, technical guidance was provided throughout plan development by a Technical Advisory Team (TAT) comprised of personnel from ten local, state and federal agencies and departments with expertise ranging from water quality modeling to comprehensive land‐use planning. Together, the WAC and TAT established water quality goals for Cunningham Lake and evaluated various combinations of structural and non‐structural management practices designed to enhance and protect reservoir water quality, aesthetics, and recreational value now and into the future. After analyzing the various management strategies and protective management practices, the project stakeholders have chosen to adopt a comprehensive management plan that will buffer the reservoir from development‐related degradation through a combination of structural protective measures and promotion of conservation‐minded watershed development.

back to top

WATERSHED MANAGEMENT TO CONTROL SEDIMENT EXPORT

Select this Article		Using Stream Classification to Develop the Channel Erosion Component in a Watershed Sediment Budget Lyle Steffen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)453 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Sediment is the largest non‐point source contaminant in our nation's streams and rivers. The primary component of any watershed management plan should be a current sediment budget. The sediment budget is a tabular listing of all the known erosion sources in a watershed. The spatial quantity (e.g., acres, miles, etc.) of each source is multiplied by an erosion rate (tons/acre/year, tons/bank mile/year, etc.) to obtain erosion quantities by source. Erosion quantities are multiplied by a sediment delivery ratio to obtain sediment yield. Typically, if potential sediment traps (functioning floodplains, lakes, reservoirs, etc.) occur within a watershed, sediment budgets are determined for each subwatershed above a sediment trap. Each subwatershed's sediment yield is then routed through the sediment trap to estimate the sediment yield delivered to the main channel. With a sediment budget, watershed managers can rank the sources of sediment yield in order of importance to help prioritize which sources should be treated first. By developing the sediment budget on a subwatershed basis, managers will also know which areas of the watershed should be prioritized for treatment. The sediment budget helps managers target limited resources to get the highest sediment reductions in a watershed with the smallest labor and capital inputs. In order to illustrate how a sediment budget is compiled, the Upper Bad River Watershed in western South Dakota will be used as an example. In particular, it will be demonstrated how the Rosgen stream classification system and the Channel Evolution Model (CEM) of Schumm, Harvey, and Watson were used to develop the channel erosion component for the Bad River Watershed sediment budget.

Select this Article		The Fire‐Flood‐Erosion Sequence in California — A Recipe for Disaster Philip J. Shaller, Douglas Hamilton, M. ASCE, Jene E. Lyle, M. ASCE, Elizabeth Mathieson, and Parmeshwar L. Shrestha, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)454 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Wildland fires are an inevitable component of many terrestrial ecosystems in California, where alternating episodes of heavy winter rainfall and dry autumnal winds, coupled with extended periods of drought increase the probability of major wildland fires. Factors influencing the intensity and duration of the post‐fire hydrologic disturbance include the nature of the local vegetation, burn severity, the geology and topography of the burn area, and the local climate. Many parts of California are underlain by granitic bedrock. Wildfires in granitic terrain result in a common suite of hydrologic aftereffects. The Lowden Ranch Fire took place in an area of granitic bedrock and granite‐derived soils in 1999. An investigation of the area in 2002 found only minor evidence of post‐fire erosion and sediment transport as a probable result of generally moderate rainfall in the winter of 1999–2000 and the presence of deep, permeable granitic sand in the affected watersheds that reduced runoff. Observations made during our site investigation indicated that by 2002 the area had recovered about 70 percent of its pre‐fire erosion resistance. This recovery was due mainly to the reestablishment of ground cover and the breakdown of any hydrophobic layer that had formed in the fire. Comparison of this area with granitic terrains of Southern California burned in 2002 and 2003 and affected by heavy rains in early 2005 indicate that such terrains are relatively resistant to erosion during light to moderate rainfall, but can experience catastrophic erosion during periods of heavy rainfall.

Select this Article		Investigation of Flood and Debris Flow Recurrence — Andreas Canyon, San Jacinto Range, Southern California Philip J. Shaller, Douglas Hamilton, M. ASCE, Parmeshwar L. Shrestha, M. ASCE, Jene E. Lyle, M. ASCE, and Macan Doroudian, M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)455 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract An investigation was conducted to evaluate the existing flood and debris flow hazard at the mouth of Andreas Canyon, a major watershed that drains from the rugged eastern slope of the San Jacinto Mountains, California. Unlike archetypical alluvial fans, which form as a result of streams of water spreading sediment and cutting new channels on the fan surface, the Andreas Canyon fan was constructed principally by debris flow processes. Eleven debris flows of varying ages were mapped on the fan surface, ten of which originated in Andreas Canyon. The debris flows are rather large, with a typical volume of about 10⁵ m³. Nevertheless, hydrologic records available for the watershed suggest that storm events necessary to yield sufficient water to mobilize a debris flow of this size are not extremely uncommon, and should recur every few decades. Archeological records, however, suggest that Andreas Canyon has not experienced a major debris flow in at least 350 years. The absence of debris flows during this period suggests that their occurrence is tied to hydrologic events that are rare or absent in the current climate regime. Details of the type of hydrologic event necessary to produce a debris flow in Andreas Canyon are currently under investigation.

back to top

GRADUATE DIVISION

Select this Article		How Planning and Management Can Benefit from Uncertainty and Risk Analyses: A Case Study on the Niagara River Samuela Franceschini, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)456 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Management decisions and policy development are oftentimes limited by the incomplete knowledge of the phenomena under study and by the inability to quantify the effective reliability of the system to be managed. It is possible to circumvent these limitations by including in the management decision process, an analysis of the variability and uncertainty of the model results. One regulatory process that can benefit from coupling the traditional deterministic modeling with the uncertainty analysis is the computation of the total maximum daily load (TMDL). By definition, in the TMDL, the margin of safety (MOS) is added to account for the inherent variability of the natural phenomena and for the limitations of their mathematical representation. In practice selection of the MOS, rarely reflects the data variability or the model uncertainty. This paper suggests a scientific method to incorporate variability and uncertainty in the computation of the TMDL by estimating a MOS based on the risk of the system of exceeding a critical concentration. The work presented here reports the results of the uncertainty and risk analyses conducted using the modified Rosenblueth Point Estimate Method to estimate the variability of lead concentrations in the Niagara River. A TMDL for lead is also computed for the first time by choosing a MOS based on the uncertainty analysis results and a selected risk of exceeding the most stringent water quality criteria.

Select this Article		3D Sediment Transport Modeling of a Hyper‐Eutrophic Lake Mamta Jain, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)457 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract The dynamics of fine sediment resuspension in Newnans Lake (mean depth of 1.6m and area 27 km²) in north‐central Florida was examined using the 3D EFDC model as part of a study to identify the mechanism by which sediment is released from a pliant, 2‐m thick muck‐laden bottom. Wind not only generates the waves, but it creates a variable wave field, and results in a weak correlation of the total suspended solids (TSS) with wind and waves. At an instrument platform towards the south end of the lake, physical and water quality parameters were measured from December 2003 to September 2004. There are two tributaries in the north end of the lake, which carry sediment into the lake. Part of the sediment load deposits in the lake and the remainder is transported out of the south end of the lake in Prairie Creek. The EFDC model was used to simulate the hydrodynamics and cohesive sediment transport in the lake. The hydrodynamic model was able to predict the measured water surface elevation and both the inflow and outflow discharges were very close to the measured values. Sediment properties (bulk density, organic content, settling velocity, bed shear strength, etc.) used in the model was determined using laboratory experiments on core and water column samples collected in the lake. The highly organic lake sediment has very low bed shear strength and a low settling velocity, this resulted in a fairly constant background concentration of 50 mg/L in the water column. The model was calibrated to achieve an optimal agreement between the measured and predicted vertical suspended sediment concentration profiles at the tower. The sediment transport model was adequately validated by comparing the measured and predicted sediment loads in Prairie Creek. The results from the calibrated and validated sediment transport model, that predicted both current and wave‐induced resuspension of the sediment, showed more fluctuations in the simulated TSS time series than that seen in the measured time series. The major spikes in the suspended solids (TSS) data (recorded at the tower) were correlated with sediments transported by the tributaries into the lake during a runoff event. The magnitude and timing of these runoff‐induced TSS spikes were adequately predicted by the model.

Select this Article		Photocatalytic Treatment of Atrazine‐Contaminated Water Shalana L. Brown, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)458 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract This research performed experimental work in the area of photocatalysis using titanium dioxide as a photocatalyst for water treatment applications. The test compared TiO₂ photocatalysis attached to a granular medium against an adsorbant, granular activated carbon, to quantify and model the degradation of atrazine in water. The result of the laboratory study showed that atrazine at low aqueous concentrations degrades rapidly with both processes. After ten minutes of reaction, the TiO₂ & GAC produced a 97% reduction compared with GAC adsorption at a 90% reduction. Statistical testing found that at higher initial concentrations photocatalysis was significantly more effective than adsorption. This work demonstrated that photocatalysis is a preferred method for treating atrazine since it degrades organic compounds rapidly in ultraviolet light.

back to top

UNDERGRADUATE DIVISION

Select this Article		Metals Contamination in Stormwater from Common Roofing Materials Julia Hafera, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)459 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract There is growing interest in the use of environmentally‐sensitive construction materials as a low‐cost component to stormwater management. Pollutant release has increased in recent years in correlation to increased development. A growing body of literature on the contributions of galvanized metal and wood products stormwater pollution loadings has concluded that these materials have the potential to release considerable levels of contaminants. Laboratory testing of these materials showed that a substantial “reservoir” of pollutants could be released. This earlier research was limited because the influence of wet‐dry weathering and other environmental influences affecting the materials' degradation could not be investigated. The current project was designed to account for these limitations. The results for metals at days 10 and 41 of exposure show that lead levels are near background for all materials. The vinyl and plastic roofings also have no additional copper detected in the runoff, but the treated and untreated woods have runoff concentrations greater than 0.5 mg/L, even after 41 days of exposure and washoff. These samples are also being analyzed for zinc, chromium and arsenic. The ultimate goal of the project is to develop a model capable of predicting the metals' release from these materials over time.

Select this Article		Drought Preparedness Paul D. Slifko, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)460 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract Drought is a natural disaster that can affect as many people as hurricanes, tornados, blizzards, and earthquakes do. Not so much by sudden changes that injure or kill, but by slow, gradual effects that are not noticed until too late. Droughts are a natural disaster that can take weeks or even months to notice. They do not happen overnight and are therefore ignored until serious problems arise. Residual effects of droughts can take their toll on communities for months and are sometimes not finished being dealt with before the next drought comes along. For these reasons, communities around the world need to be more equipped to handle the difficulties that come with a drought before the problem becomes serious. Drought preparedness is a multi‐faceted action plan that strives to make people more aware of the problem and seeks to shed light on potential solutions.

Select this Article		Environmental vs. Economical Benefits of Dams from Different Perspectives Luis Pettingill, S. M. ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40856(200)461 Online Publication Date: 25 October 2007 Full Text: \| Download PDF
	+ -	Show Abstract In this essay, I will describe and compare differences and similarities between a third world country and a first world country. Both countries have different needs, resources, and ways of thinking. This is an attempt to explain the reasons why Paraguay is behind in environmental damage control, especially when it comes to the symbol strength that comes with having two of the biggest hydroelectric dams in the world. The United States however is leading when it comes to dismantling dams that are harmful to the ecosystem; the US has a special concern for plants and animals that are near extinction. In today's age, environmental concerns in first world countries like the United States revolutionized the planet with the development of the Green movement; expressing a general concern of today's resources for tomorrow's future.