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WRPMD 1999 — Preparing for the 21st Century Proceedings of 29th Annual Water Resources Planning and Management Conference

June 6–9, 1999 Tempe, Arizona, USA

Editor(s): Erin M. Wilson

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FEATURED SPEAKERS

Select this Article		Modeling Water Resources Opportunities, Challenges and Trade‐Offs: The Use of Shared Vision Modeling for Negotiation and Conflict Resolution Richard N. Palmer, M.ASCE, William J. Werick, Allison MacEwan, and Andrew W. Woods, S.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)1 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper introduces the concept of Shared Vision Modeling and discusses its relevance to developing solutions to highly conflicted water resources problems. It begins by suggesting that although our computing resources have increased dramatically during the past two decades, our success rate in implementing computer generated solutions to water resources problems has not. The paper focuses on the use of Shared Vision modeling to guide model construction and to ensure that models are successfully integrated into the broader conflict resolution process. The paper concludes with examples of where Shared Vision Models have been used and summarizing their relative success.

Select this Article		Water for the 21^st Century: Emerging Issues Herman Bouwer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)2 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Population growth and higher living standards will cause ever increasing demands for good quality water and ever increasing sewage flows. At the same time, irrigation and associated water demands will increase to produce adequate food for growing populations. Also, there will be more environmental concerns about aquatic life, recreation, scenic values, riparian habitats, and other surface water benefits. Thus, increased competition for water can be expected. This will require intensive management and international cooperation. Since almost all liquid fresh water on the planet occurs underground, groundwater will be used more and more and, hence, must be protected against depletion and contamination, especially from non‐point sources like intensive agriculture.

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FORECASTING & WATER RESOURCES MANAGEMENT

Select this Article		Use of Climate Forecasts to Improve Agriculture in West Africa — A Case Study of Burkina Faso Paul Kirshen, Dr., Keith Ingram, Dr., Ian Flitcroft, Dr., and Carla Roncoli, Dr. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)3 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The United States National Oceanic and Atmospheric Administration (NOAA), the Hadley Centre for Climate Prediction and Research in the United Kingdom, the International Research Institute (IRI), and West African national meteorological services produce regional seasonal precipitation forecasts based upon El Nino‐Southern Oscillation (ENSO) and other global and regional meteorological conditions for the Sahel‐Soudan region of West Africa. (The Sahel‐Soudan region includes: Senegal, Mauritania, Mali, Burkina Faso, Niger, Chad, Sudan, and parts of Benin, Nigeria, Cameroon, and the Central African Republic.) Others researchers are developing experimental methods to use these forecasts and other data to forecast local precipitation. The objective of this three‐year, multi‐discipline research project, which started in June 1997, is to better understand how regional and national institutions and organizations, and farm families in the semi‐arid Sahel‐Soudan Region, West Africa can use seasonal precipitation forecasts to improve productivity and efficient use of resources in agricultural production systems. The project will also identify and recommend points of entry and appropriate modalities for integrating meteorology‐based forecasts with indigenous predictions and farming practices in ways that are culturally acceptable and positively affect quality of life, food security, and environmental sustainability. The results of the project will also lead to the design of an appropriate pilot project with Burkinabe and other collaborators in the region to more fully test the application of seasonal forecasts to improve agricultural production systems.

Select this Article		The IRI Seasonal Climate Prediction System Simon J. Mason, Lisa Goddard, Nicholas E. Graham, Elena Yulaeva, Liqiang Sun, and Phillip A. Arkin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)4 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract One of the most significant advances in the atmospheric sciences in recent years has been the development of an ability to predict ocean‐atmosphere variability in the equatorial Pacific Ocean. Occasional basin‐wide warming or cooling of equatorial sea‐surface temperatures, known as El Niño and La Niña events, together with an associated oscillation of atmospheric pressure over the South Pacific Ocean, known as the Southern Oscillation, can have global climate repercussions. Both extremes of the El Niño ‐ Southern Oscillation (ENSO) phenomenon have been associated with temperature and rainfall anomalies around the world. The influence of the tropical oceans on the atmosphere forms the theoretical basis of seasonal climate forecasts. The International Research Institute for climate prediction (IRI) was formed in late 1996 with the aim of fostering the improvement, production and use of global forecasts of seasonal‐to‐interannual climate variability for the explicit benefit of society. The development of the 1997/98 El Niño event provided an ideal impetus to the IRI Experimental Forecast Division (IRI‐EFD) to generate seasonal climate forecasts on an operational basis. In the production of these forecasts an extensive suite of forecasting tools has been developed, and these are described in this paper.

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INSTITUTIONAL ASPECTS OF WATER RESOURCES MANAGEMENT

Select this Article		Redefining Rainfall Classification Michael K. Glazner, Saša Tomić, and Benjamin White ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)5 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Phrases such as “S‐year rainfall” or “loo‐year storm” are commonly used in everyday life to describe rainfall events. However, these phrases are frequently confusing to the general public and insufficient for practicing engineers. For an average news listener, a phrase such as “5‐year event” does not say much about the severity of the rainfall event. Additionally, this phrase is not of much help to a practicing engineer since it does not include the duration of the rainfall event in question. This paper suggests a new method of classifying rainfall events. The proposed Haestad Severity Index (HSI) categorizes rainfall events using ten levels of magnitude.

Select this Article		Technical Tools in a Political Environment: Uses and Abuses Lindell Ormsbee, Dr., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)6 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Kentucky River Authority was first established by the Kentucky General Assembly in 1986 to take over operation of the Kentucky River Locks and Dams 5 through 14 from the United States Corps of Engineers. Following the drought of 1988, the Authority was given a mission to protect and improve the waters of the Kentucky River through environmental management of the entire watershed. It is the first effort by the Commonwealth of Kentucky to protect a great water resource through watershed management. In 1995 the Authority contracted with the Kentucky Water Resources Research Institute to perform a comprehensive water supply study for the Kentucky River Basin. The Kentucky Water Resources Institute was chosen ostensibly so as to provide a “unbiased” and scientifically based study. This study resulted in the development of two computer models KYBASIN and KYQUAL which were used to develop and evaluate five separate water supply alternatives for the Kentucky River Basin. These alternatives included: 1) conservation, 2) installation of temporary crest gates on dams 9–14; 3) construction of a large dam on the Kentucky River, 4) construction of a smaller dam on a tributary to the Kentucky River, and 5) construction of a treated‐water pipeline from Louisville to Lexington.

Select this Article		Statewide Regional Water Management Planning: The Texas Approach Lloyd V. Urban, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)7 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 75th Texas Legislature passed Senate Bill 1 in 1997. The purpose of the legislation is to provide for orderly development, management, and conservation of water resources and to ensure that all regions of the state are adequately prepared to respond to drought conditions. After regional plans are developed in September 2000, the Texas Water Development Board will formulate a statewide plan in the year 2001. The bottom‐up approach represents a significant departure from the previous top‐down approach utilized by the state. Initial estimate for developing the regional and state plans is $22 million. The effort has created a flurry of activity as regional planning groups gear up to meet the challenge presented by the rules, schedules, costs and other commitments mandated by the bill. This paper outlines the key features of Senate Bill 1 and discusses the process, progress, and frustrations of regional planning in the state.

Select this Article		Stormwater Master Planning in the Desert Southwest Kathryn L. Hendricks, P.E., M.ASCE and Carl Doak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)8 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Despite the arid climate in the southwest, intense storms can deluge the area causing short term flooding problems. Communities in other parts of the country control stormwater runoff by draining it from streets and property into pipes and channels which drain to creeks, rivers, lakes, and oceans. In the southwest, particularly the Phoenix area, communities do not always have channels available nearby for drainage. In addition, the cost and public perception of installing large pipes and systems, which are rarely used to full capacity, has challenged southwestern communities to find other methods to control stormwater runoff. Chandler, a growing City near Phoenix, has confronted these challenges for stormwater management.

Select this Article		Nonpoint Pollution Abatement a Watershed Approach Fred J. Brenner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)9 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Two watersheds in northwestern Pennsylvania were evaluated as to their potential for point and nonpoint source pollution. The Slippery Rock Creek watershed has been adversely impacted by acid mine drainage (AMD) for over 100 years while the Neshannock Creek watershed is primarily being degraded by agriculture. In the Slippery Rock Creek watershed, a variety of passive treatment technologies, including wetlands, limestone drains, and vertical flow systems, are being employed to restore the watershed at a total cost of $8,929,500. In the Neshannock Creek watershed, the restoration efforts will focus on the enhancement and development of reparian wetlands and stream fencing at a cost yet to be determined.

Select this Article		The Case Against Representative Stormwater Runoff Monitoring Robert D. Chandler, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)10 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract One often stated objective of stormwater runoff monitoring programs is to characterize the quality of stormwater runoff from one or more “representative” areas, that is, areas having predominantly residential, commercial, industrial, roadway, or open space land use. Representative urban runoff monitoring has been the focus of many sampling efforts over the past 30 years, including the Nationwide Urban Runoff Program (NURP) study. In the early 1990's, many large municipalities were required to conduct representative urban stormwater runoff monitoring in order to obtain a National Pollutant Discharge Elimination System (NPDES) stormwater discharge permit, and a number of NPDES permits now in effect require some form of representative urban stormwater runoff monitoring. Concentrations of pollutants in stormwater are notoriously variable, and in the case of representative runoff monitoring projects, a large number of sample data is required in order to perform any kind of in‐depth statistical analyses. This makes representative urban stormwater runoff monitoring programs extraordinarily expensive, and this commitment of resources is not always—some say, not ever—rewarded with results that substantially support the needs of decision makers. The purpose of this paper is to put forward a case for discontinuing representative stormwater runoff monitoring. First, a simple method for estimating the costs involved in stormwater runoff monitoring is proposed. Next, an example of the type of analyses that can be performed using data already available is provided. Finally, using the cost‐estimating model and the results of the statistical analysis, it is shown that an exorbitant amount of money would be required to further “refine” estimates of representative runoff concentrations.

Select this Article		Stormwater Runoff Effects on Florida's Automobile Salvage Yards Andrew Dzurik, P.E., M.ASCE and Danuta Leszczynska ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)11 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents the preliminary results of the study on the environmental effects of stormwater runoff from automobile salvage facilities. An analysis of existing data provides the basis for assessing overall impact on water resources. The extend to which automobile salvage yards contaminate water resources are estimated by applying waste generation factors extrapolated from the sample site investigations and other available data on auto salvage yards.

Select this Article		CSO Modeling using RUNOFF and TRANSPORT Modules of SWMM Michael S. Krabacher, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)12 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The combined sewer area of Northern Kentucky is located in the northern portion of Campbell and Kenton Counties and covers approximately nine square miles. This area includes 97 combined sewer overflows (CSO) and numerous sanitary sewer overflows (SSO) that discharge into the Ohio River, the Licking River, and Banklick Creek. The separate sewer systems from various municipalities located upstream discharge into the combined sewers. The combination of the combined sewer areas and the separate sewer areas located upstream make up the CSO study area. The goal of the CSO model is to accurately represent the CSO overflow and SSO bypass hydrographs discharged to the receiving streams during a given rain event. The calibrated model is then used to generate yearly CSO loadings through continuous simulation. The model output can be used in conjunction with a stream water quality model to evaluate the effects of different CSO control alternatives on the receiving streams. The software chosen to analyze the study area was the CAiCE software version of the EPA Storm Water Management Model called XP‐SWMM32. The model calibration was performed using three months of flow monitoring data at 15 CSO sites and numerous sanitary sewer locations. The CSO monitoring locations were calibrated using the rainfall data record for the entire monitoring period. The CSO basin parameters were estimated using GIS data and combined sewer mapping resources. The model calibration was performed by altering the total catchment area, percent impervious, and the infiltration parameters in RUNOFF. The results indicate that the model simulations accurately estimate the amount of overflow volume monitored at each CSO. The results also indicate that the GIS data can accurately predict the basin parameters for those CSO locations that were not monitored.

Select this Article		The Misuse of Hydrological Modeling in the Establishment of Stormwater Management Regulations Thomas J. Olenik, Ph.D., P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)13 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The design of stormwater management systems has become common practice in the last twenty years. These types of analyses are based upon the design and construction of isolated ponds based upon pre‐ and post‐development flow rates, volumes and water quality parameters. These design principles have been codified in the various regulatory bodies that govern the process in the state of New Jersey and other jurisdictions. This paper addresses some of the engineering flaws that are rarely challenged by the profession. The micro‐ and macro‐management of stormwater design is examined from a design engineer's viewpoint based upon the traditional establishment of design values and not just meeting regulatory edicts. The continuation of engineering design based upon design values that are not verifiable will only result in more wasted resources.

Select this Article		Detention Basin Release Rate Determination for Urbanizing Watersheds in St. Louis County, Missouri Peter S. Miller, P.E., M.ASCE and Eric Loucks, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)14 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Metropolitan St. Louis Sewer District (MSD) has responsibility for the management of stormwater drainage as well as conveyance and treatment of sanitary sewage within its boundaries. In conducting these responsibilities, MSD has identified the need to address a multitude of drainage related problems. These problems and their potential solutions has demonstrated the need for a comprehensive Stormwater System Master Improvement Plan (SSMIP) for the District, which incorporates a long‐term plan to implement comprehensive and technically sound solutions to these problems. MSD has initiated the SSMIP, which includes two major components that affect the level of stormwater service that MSD provides to its customers. The first is the development of stormwater policies, standards and rules to provide the appropriate level of service throughout the District. The second is the preparation of individual watershed management plans to recommend specific improvements to correct existing stormwater problems and to prevent future problems from occurring. The purpose of the Caulks Creek and Cowmire Creek Watershed Master Plans (WMP) is to develop a comprehensive set of recommendations that will correct high priority problems in the watershed and recommend stormwater controls for new development that will prevent future problems from occurring.

Select this Article		Using a Geographical Information System to Develop Hydrologic Input Parameters Scott J. Kenner and Jason T. Love ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)15 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Urban drainage models require several physical parameters as input for modeling. These parameters vary spatially and require interpretation of maps, which often vary in scale and accuracy. Data requirements can be quite extensive and acquisition and manipulation of the data are time consuming. Additionally, models require updating due to basin changes and development. The GIS Weasel was developed by the US Geological Survey and is available to the public. The GIS Weasel is a graphical user interface developed to aid hydrologists and other physical process modelers in the delineation, characterization, and parameterization of an area of interest, drainage nets, and modeling response units for distributed and lumped parameter models. The City of Rapid City currently uses the coupled models CUHP and UDSWMM for modeling urban drainage systems. This project presents the process for using GIS Weasel and ARC/INFO to automate parameterization of the urban hydrology model CUHP.

Select this Article		Model Choice and Basin Scale for Urbanizing Watersheds in Appalachian Headwater Areas V. K. Lohani, Jeff Chanat, D. F. Kibler, and Ryan Fedak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)16 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Present paper describes results of hydrologic simulation studies being carried out in southwest Virginia as a part of an EPA/NSF multi‐disciplinary project involving hydrology, hydraulics, economics and policy, and biology research components. The Hydrologic Simulation Program Fortran (HSPF) has been calibrated for a sub‐watershed of the Upper Roanoke River system. The model will provide inputs needed by other components of the study in describing environmental impacts of urbanization.

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INNOVATIVE WATER TREATMENT

Select this Article		Executive Order 13112: Invasive Species Jonathan W. Bulkley, F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)17 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Invasive species pose a serious environmental threat to this country and countries all around the world. Global commerce essential to the economic well being of the citizens of the world provides important pathways whereby invasive species may move from their natural habitats to new locations where the conditions of the ecosystem may enable the invasive species to grow and multiply to the extent that native species are lost and severe economic loss, environmental harm, and harm to human health may occur. Executive Order 13112 signed by President Clinton on February 3, 1999 establishes a rational process to mobilize and coordinate the activities of the federal government in order to mount an effective and cost efficient set of programs and activities to mitigate the threats posed by invasive species. This paper describes the nature of the threats posed by invasive species and presents the major elements of Executive Order 13112. Observations are provided regarding both the nature of the multiple threats from invasive species and the potential of the provisions of Executive Order 13112 to meet these threats.

Select this Article		Development of an Aquatic Nuisance Species Dispersal Barrier Philip B. Moy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)18 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Chicago Sanitary and Ship Canal connects the Great Lakes with the Mississippi River and forms a two‐way aquatic invasion corridor between these drainages. As part of the nation‐wide effort to prevent the spread of non‐native invasive aquatic species, the U.S. Army Corps of Engineers is carrying out a demonstration study of placing an aquatic nuisance species dispersal barrier in the canal. Ideally the barrier would not interfere with navigation or water flow and would affect only a limited reach of the canal. A combination of deterrent and lethal approaches will be required for greatest effectiveness. The first step in the study will use a micro‐pulsed DC electric array. Other methodologies will be added in the future. Ultimately target organisms would include planktonic species.

Select this Article		Improving Clearwell Design Using Computational Fluid Dynamics Sanjay Reddy, P.E., Jerry Russell, P.E., Ramesh Narasimhan, P.E., and Catherine Burns ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)19 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The City of Phoenix was concerned with possible short‐circuiting problems at the Union Hills and Val Vista Water Treatment Plant reservoirs. Chemical tracer tests conducted by the plant personnel confirmed that the reservoirs were short circuiting and the T₁₀/T values were 0.1. In order to alleviate the short‐circuiting problems and minimize chemical disinfectant usage, baffles were added to the reservoirs. Computational fluid dynamic models were utilized to develop baffle configurations and inlet jet dissipating devices. In order to verify the predictive capability of the CFD models, field tracer data was compared with CFD simulated tracer results. The CFD data matched field tracer data within 10 percent. At the Union Hills reservoir, two baffles oriented in the east‐west direction increased T₁₀/T values of the reservoir to 0.27.

Select this Article		Privatization of the City of Atlanta's Water System: A Cost Savings Initiative and a Plan for the Future Steven Labovitz ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)20 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The City of Atlanta owns two water treatment plants with a combined capacity of 184.5 million gallons per day (mgd). In addition, Atlanta and Fulton County jointly own a third water treatment facility. Water distribution facilities include three pumping stations with a capacity of 430 mgd and 90.5 million gallons of storage, and 2,400 miles of water mains. There are 12 pumping stations and 2,200 miles of sanitary, storm and combined sewers. Prior to 1998, the portion of the water system owned separately by the City of Atlanta was operated by the City's Department of Water and two divisions of the Department of Public Works: the Division of Wastewater Services and the Sewer Division. The water treatment plant owned jointly with Fulton County was operated and maintained by a private firm. The Department of Water was responsible for collecting raw water from the Chattahoochee River, treating it, and distributing it to approximately 1.5 million people in the Atlanta metropolitan area. The Sewer Division maintained Atlanta's sanitary and combined sewers and conveyed wastewater from approximately 1.2 million customers to the City's wastewater treatment plants. Finally, the Wastewater Services Division operated and maintained three wastewater treatment plants and related combined sewer overflow facilities.

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WATER RESOURCE SYSTEMS MODELING

Select this Article		Optimization of Water Resource System Using Genetic Optimization with Both Deductive and Inductive Simulation Models Lindell Ormsbee and Sirinavasa Lingireddy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)21 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The optimal control problem associated with many water resource systems may be formulated as a nonlinear optimization problem involving a nonlinear objective function subject to both implicit system (state) constraints and implicit bound constrains. A general solution is proposed that uses a disaggregated or dual level approach in which the system state equations are removed from the control formulation and evaluated externally using mathematical simulation while the resulting optimization formulation is solved using a genetic optimization routine. Potential algorithm performance enhancement may be obtained by replacement of the simulation algorithm with a neural network representation. The resulting network may be trained on‐line using real time data or it may be obtained using multiple off‐line state predictions obtained from a simulation model. Potential applications of the approach are presented along with a discussion of potential problems.

Select this Article		Optimized Calibration for Unsteady Flow Modeling Using a Genetic Algorithm Daniel Sanchez and Jerome A. Westphal ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)22 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The calibration of an unsteady flow model generally relies on the estimation of roughness coefficients, which act as descriptors of friction resistance along the channel. Here an optimized procedure is implemented by incorporating a genetic algorithm (GA) to automate the process. This approach is suitable because discrete parameters are considered. The target is a one‐dimensional unsteady flow model in which the roughness coefficient is allowed to vary not only along the river axis, but also dynamically with discharge. The objective function is the root mean square of the difference between measured and computed water levels at a given cross section. This function is minimized using several strategies for reproduction and crossover. Several fitness functions are tested as well. The application results are encouraging and the implementation is less complicated than in methods where the objective function has to be related explicitly to the constraints of the application.

Select this Article		Real‐Time Operation of Water Resources Systems: On‐ versus Off‐line Optimization A. J. Clemmens ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)23 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The literature is full of articles dealing with the optimal operation of water resources systems. However, I am not aware of any water resources systems that actually use optimization on‐line in real time for operations. There are likely a number of reasons for this. First, these optimization models are not well accepted by operators who are used to doing things manually. They appear to the operators like black boxes — put in some numbers and out spits an answer. Second, it is likely that many of the optimization models developed do not include all the real‐world constraint that the operator has to deal with. In the field of canal automation, application of real time control is faced with similar acceptance problems. Various optimal and predictive control methods have been proposed in the literature. If a state‐feedback framework is used, the optimization can be done off line. Control decisions then essentially can be found from simple matrix calculations. In one scheme, the state vector represents real physical variables and a subset of the gain matrix can be framed so that it represents simple Proportional‐Integral (PI) control. In this form, the control decisions can be easily explained to operators in terms of simple control‐system logic, although performance is more difficult to guarantee compared to the black‐box‐type state‐vector. Further, by using a hierarchical control framework, manual and open‐loop controls can be imposed over the top of the state‐feedback controller. Operators are thus allowed to manually override the system as desired — adding to operator acceptance. This control system is currently being installed on the Salt River Project's upper Arizona Canal for initial testing. One drawback of this system is that since optimization is done off line, changes in constraints cannot be easily accounted for, as they can with predictive on‐line optimal control methods.

Select this Article		Numerical Modeling of an Unsteady Flow in a Complex Sewer Network Matahel Ansar, Ph.D., Shi‐En Shiau, P.E., and Behrouz Fathali, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)24 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An unsteady hydraulic model for the influent lines of the 23^rd Avenue Wastewater Treatment Plant (WWTP) in Phoenix, Arizona, was developed using XP‐EXTRAN. XP‐EXTRAN is a sub‐module of XP‐SWMM32, which is a comprehensive computer program used for hydrological and hydraulic simulations in sewer networks. The developed hydraulic model solves the St‐Venant equations in a complex sewer network. The model was calibrated against field measurements obtained using acoustic velocity sensors and acoustic depth sensors. Good agreement was obtained between the numerical results and the measurements. The calibrated model was used to develop alternative solutions to the surcharge and cleansing velocity problems in the influent lines of the 23^rd Avenue WWTP. The paper describes the hydraulic modeling of the influent lines, a comparison of the hydraulic model results with field measurements, and the proposed solution to the surcharge and cleansing velocity problems.

Select this Article		Assessing the Impacts of Institutional Changes in Water Rights on Hydrologic Conditions within a River Basin John C. Tracy, Ph.D., P.E., A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)25 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Walker Lake is a terminal desert lake located in west‐central Nevada. The only loss of water from the lake is due to evaporation, and over time, this results in salts and other non‐reactive solutes being concentrated in the lake water. The primary source of inflow to Walker Lake is from the main channel of the Walker River, which is formed near Yerington Nevada by the convergence of its two main tributaries, the East and West Walker Rivers. The Walker River watershed covers an area of approximately 11,110 square km, and has its headwaters in the eastern Sierra Nevada mountain range in eastern California. The headwater flows are primarily due to snowmelt, which typically becomes significant in late spring, and tapers off in late summer. Thus, flow in the tributaries are normally low during January, February and March, increase during April and May, peak during June and July, and then gradually decline throughout the rest of the year. The headwater flows can vary significantly from year to year, with the lowest recorded headwater flow being 107 million m³ in 1977, and the highest yearly recorded headwater flow being 924 million m³ in 1983. On average, the yearly headwater flow is approximately 403 million m³.

Select this Article		Application of a GIS‐Based Water Allocation Planning Model to Central Texas Quentin W. Martin, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)26 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Comprehensive regional water planning for a large section of Central Texas is a major responsibility of the Lower Colorado River Authority (LCRA). In its planning efforts, the LCRA has adopted a new water allocation model developed at the University of Texas at Austin for providing automated distribution of water supplies to areas of water need. This water balancing model is based on using a geographical information system as the primary user interface for understanding water supply and demand conditions and identifying areas of water surplus or shortage over a board geographical area. Application of the model to the 33‐county LCRA water service area is discussed. Future potential applications and useful extensions of the model are also identified.

Select this Article		A “Modeler's Model” of South Florida Water Management Alternatives David W. Watkins, Jr., A.M.ASCE, Kenneth W. Kirby, S.M.ASCE, and Richard E. Punnett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)27 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Hydrologic Engineering Center Prescriptive Reservoir Model (HEC‐PRM), a generalized network flow programming model, has been applied to support the feasibility phase of the Central and South Florida Project Comprehensive Review Study (“Restudy”). The objective of the Restudy, performed by the Jacksonville District of the US Army Corps of Engineers and the South Florida Water Management District, is to recommend a plan for improving environmental quality and urban and agricultural water supply reliability affected by the Central and South Florida water management project. As a “modeler's model,” HEC‐PRM was used to screen alternatives with respect to several environmental and water supply criteria, as well as to gain insights to operating strategies that could be tested and refined through simulation modeling.

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IMPACTS OF WATER REUSE ON GROUNDWATER QUALITY IN ARIZONA

Select this Article		Implications of Soil Aquifer Treatment for Sustainable Water Reuse on Groundwater Quality Peter Fox, Margaret Nellor, Bob Arnold, Kevin Lansey, Randy Bassett, Charles Gerba, Gary Amy, William Yanko, Rodger Baird, Martin Reinhard, Sandra Houston, and Joerg Drewes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)28 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This presentation will present an overview of a multiple‐year program of study to establish the efficacy and sustainability of wetlands and soil‐aquifer treatments leading to indirect potable water reuse. Wetlands and infiltration/subsurface treatment will be considered as a single treatment system for purposes of aquifer protection — primarily protection from nitrate and dissolved organics of wastewater origin. Soil‐aquifer treatment is envisioned as consisting of (i) infiltration through a biologically active infiltration interface (<1m in depth) at the soil/water boundary of the infiltration basin; (ii) percolation through an extensive vadose zone, 10–100 feet in depth; and (iii) storage/transport in the underlying aquifer (6–24 months, >500 horizontal feet) pending withdrawal at proximate production wells. Water quality benefits in terms of organic carbon, nitrogen and pathogen attenuations will be assigned to each treatment zone based on the proposed field program and supporting laboratory experiments. At least seven field sites have been selected for use in the study based on specific strengths such as depth to groundwater, quality of groundwater data, instrumentation and geographical considerations. Results will be analyzed within a systems framework that can be driven by local data and constraints from other geographical locations. A multidisciplinary team consisting of environmental researchers from three western states; water and wastewater practitioners from Arizona and California — states that will eventually depend heavily on wastewater reclamation/reuse to meet water demands; and experts in (aquatic) organic chemistry, virology, hydrology and systems analysis has been identified to overcome these shortcomings. The proposed project will generate practical tools with which to assess water quality and/or gage compliance with regulatory (reuse) criteria.

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WATER DISTRIBUTION SYSTEMS ANALYSIS: APPLICATIONS & CASE STUDIES

Select this Article		Challenges in the Development of Hydraulic and Water Quality Models of Air Force Base Water Systems Y. Hasit, PhD, P.E., F. Grablutz, P.E., K. Momberger, P.E., J. Rhoades, P.E., and G. Nault ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)29 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract As with many municipal water systems, Air Force base drinking water systems must cope with aging infrastructure. This, in conjunction with a heightened scrutiny of water quality in the distribution system, has created problems for many bases. Air Combat Command Headquarters (HQ ACC) undertook a study to develop hydraulic and water quality models of the water distribution systems at five ACC bases. The models were developed by Roy F. Weston, Inc. (WESTON) using commercially available software (H2ONET and WaterCAD) and provided each base with a tool to analyze its water system with respect to current and proposed base missions. This paper describes the challenges faced in compiling available data and collecting previously unavailable information in order to create calibrated, useful models, and conduct the required analysis.

Select this Article		Rapid Chloramine Decay in Portland's Distribution System Lee H. Odell, P.E. and Curt Ireland, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)30 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Chloramination in drinking water is often employed to help maintain a disinfectant residual in distribution systems where free chlorine residuals are difficult to maintain. Chloramine decay rates are often fairly low, however, a number of factors can contribute to accelerated chloramine decay. The objectives of this paper are (1) to document instances of rapid chloramine decay in the Portland Bureau of Water Works distribution system and (2) to evaluate possible contributing factors to the decay rates.

Select this Article		Chlorine Decay in Auckland's Distribution System Bassam Halabi, Angela Boothroyd, and Naresh Singhal, Dr. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)31 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The first step in finding a cure for water quality deterioration in water distribution systems is to study how water quality varies within the distribution system and the causes and effects of this variation. This paper discusses a pilot study aimed at assessing the propagation and concentration of chlorine in a water distribution network and developing a relationship between chlorine decay rate and the average age of water in a particular water distribution system. The primary aim of the project was to develop a simple operational tool that accounts for the chlorine decay, with reasonable accuracy, in Auckland's Central Business District (CBD) distribution system. The model has been used by Metrowater, the largest water supply distribution company in Auckland, to understand and improve the water quality in the CBD reticulation system.

Select this Article		Water Quality Modeling: A Case Study A. Marinelli and G. Furlani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)32 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The water distribution network of an italian town of about 100000 inhabitants has been the object of different field investigations and simulations aimed at reproducing discharges, pressures and chlorine concentrations at measurements points. The water network length is estimated to be equal to 350 Km about, while the simulated network length is equal to 100 Km. The simulated network has been choosen following the rule of a diameter greater than 80 mm or even less when the pipe is the only one that connects different portions of the network. A first stage of the field investigations was aimed at water demands measurements collection and analysis. Other elaborations on hystorical data allowed to estimate the average, the minimum and the maximum daily discharge and the average percentage of water losses. Considerations based on the material, on the age of construction, on direct experience and on calibration results allowed to define hypotheses on water losses non‐uniform distribution. Field measurements of pressure have been done on main pipes in 8 different points for 24 hours. Field measurements of chlorine concentrations have been done on 6 important nodes of the network: 90 different samples have been collected in 24 hours. Estimation of the bulk coefficient for chlorine decay has been done by measurements on water samples with time step of one hour. Epanet has been adopted as the model for hydraulic and quality simulation. The calibration procedure is mainly involved on water losses and chlorine wall coefficients distribution identification.

Select this Article		Chlorine Decay Modeling in the S.Giacomo Storage Tank, Napoli C. Gualtieri, E. Mastrangelo, U. Potenza, and G. Rotondo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)33 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water quality problems have been recognized worldwide from long time as representing a basic topic in drinking water networks management; the needs for an effective protection and monitoring of drinking water has given rise to specific regulations in each country. Italian regulation on drinking water quality is based on the 236/88 Act, which aknowledges the EU 80/778 Directive; 236/88 Act establishes quality standards and criteria for drinking water using physical, chemical and bacteriological parameters. Particularly, 236/88 Act considers for each parameter two values, the maximum allowable concentration (MAC), which is a threshold limit, and a guide value (GV), to whom drinking water utilities should address their efforts to improve water quality. This act fixes sample frequency and analytical methods for sampling and monitoring in the distribution network. However, in many EU countries the tendency to submit EU 80/778 Directive to a revision is growing; in fact, some critical points in the EU 80/778 pertain to the treatment costs, which are related to water sources and are not taken in account in the Directive, and to some parameters, whose CMAs should be updated; moreover, for aesthetical parameters or those which do not affect human health, such as, for example, temperature, conductivity, colour, odour and taste, CMAs should be deleted and substituted by GVs.

Select this Article		Application of Models to Solve Water Quality Compliance Issues F. Grablutz, P.E., Y. Hasit, PhD, P.E., K. Momberger, P.E., S. McCammon, and G. Nault ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)34 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Like any municipal water utility, U.S. Air Force bases must comply with the drinking water standards established by the Safe Drinking Water Act (SDWA). Air Combat Command Headquarters (HQ ACC) funded a project to evaluate the drinking water systems at the 22 bases under its command. The primary focus of the study was to identify water quality compliance problems and to recommend corrective measures. For five of the bases, hydraulic and water quality models of the water distribution systems were developed to provide each base with a tool to analyze its water system with respect to current and proposed base missions. Roy F. Weston, Inc. (WESTON) developed the models using commercially available software (H2ONet and WaterCAD). For four additional bases, existing hydraulic models were modified and imported into EPANet to analyze specific water quality problems in their distribution systems. This paper describes the work at two Air Force bases where the modeling identified cost‐effective solutions to ongoing water quality compliance issues. One base was in the western region of the U.S. and the other was in the southern U.S.

Select this Article		Problems with SCADA Data for Calibration of Hydraulic Models Douglas C. Howie, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)35 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract When calibrating a hydraulic model, more field information may not be better. The volume of information available from SCADA systems that collect flow and pressure information within a distribution system may be more than a modeler would prefer. Problems such as timing of data collection, inconsistent data (i.e. hydraulic grades indicate flow in one direction with metered data indicating flow in the other), and the difficulty in identifying whether a set of changes to the data makes for a better calibration begin to appear as the amount of data increases. This paper discusses several of these problems and identifies how they can be overcome. Examples from a project where SCADA was used in calibration will be used to illustrate various points.

Select this Article		Combining Hydraulic Modelling and Operational Data to Understand Chlorine Decay in a Distribution System Vincent Gauthier, Marie‐Claude Besner, Benoit Barbeau, Michèle Prévost, and Robert Millette ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)36 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The very marked decay of chlorine measured in one section of the distribution system of a large North American city, and the fluctuations in this decay, were studied. The results obtained from operational data collection, from dedicated flow measurements and from Epanet hydraulic modelling demonstrate that low chlorine residuals in this particular distribution system section cannot be attributed to any exceptional consumption by corrosion particles, loose deposits or biofilms. On the contrary, the hydraulic configuration of this distribution system area (tank design and pumping cycles) results in such high residence times that the low chlorine residuals observed are self‐explanatory. Detailed analysis of the EPANET results indicates that the principles of the hydraulic (dys)functioning in this zone are well described by the model, which can be relied upon to compute and compare several design or operational solutions to minimize residence times, thereby increasing the chlorine residual in the area.

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WATER DISTRIBUTION SYSTEMS ANALYSIS II: SIMULATION METHODS

Select this Article		Parallel Computing in Water Network Analysis and Optimization Processes Vicente Hernández, Antonio M. Vidal, Fernando Alvarruiz, Jose M. Alonso, David Guerrero, Pedro A. Ruiz, Fernando Martínez, Juan Vercher, and Bogumil Ulanicki ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)37 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In this paper, a parallel computing based demonstrator for the simulation and control of water networks is presented. EPANET package has been the starting point for the demonstrator. The paper discusses the approach used in hydraulics simulation by means of the Gradient method, and in water quality simulation by means of the DVEM method. Finally, a key point in the project is the development of a methodology for leakage reduction by finding the optimal pressure reducing valve settings.

Select this Article		Velocity Profiles, Unsteady Friction Losses and Transient Modelling Bruno Brunone, Bryan Karney, and Marco Ferrante ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)38 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Transient flows in closed‐conduits have traditionally been modeled as one‐dimensional flows with the assumption that both velocity profiles and friction losses can be accurately predicted on the basis of equivalent steady state (i.e., average) values of velocity. More recently, a host of more complex fluid models have been suggested, but there has been little experimental basis for selecting one model over another. This paper reviews the significance of these questions and briefly overviews various historical approaches that have been proposed for improving the numerical modeling of the fluid structure during transient events. To address the critical need for better data, an experimental set‐up in Italy is described and preliminary measurements of velocity profiles during two transient events caused by valve operation are presented.

Select this Article		The EPANET Programmer's Toolkit for Analysis of Water Distribution Systems Lewis A. Rossman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)39 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The EPANET Programmer's Toolkit is a collection of functions that helps simplify computer programming of water distribution network analyses. The functions can be used to read in a pipe network description file, modify selected component properties, run multiple hydraulic and water quality analyses, retrieve selected output results, and write formatted output reports. The toolkit is especially useful for developing applications, such as optimization models, that require running many network analyses with modified input parameters. It can also simplify adding analysis capabilities to integrated network modeling environments based on CAD, GIS, and database packages.

Select this Article		Modeling of Pressure Regulating Devices: The Last Major Problem to be Solved in Hydraulic Simulation Angus R. Simpson, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)40 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Hydraulic simulation of water distribution systems using computer software appears to have reached a very mature level of practice. There does not appear to be many other improvements that can be made to the basic underlying solution algorithms. While this statement is mostly true, there still remains one area that results in problems when developing simulation models. In discussions with water distribution modeling practitioners, the most commonly mentioned remaining problem is stability of computers programs in the presence of pressure regulating devices. The three most common pressure regulating devices are pressure reducing valves, flow control valves and pressure sustaining valves. The difficulty in computer codes is that the status of the device is not known a priori. Consider a pressure reducing valve (PRV) — it may have one of three states. For the first state, the valve operates normally ‐ such that the valve is in a partially closed or throttling position to maintain the set pressure on the downstream side of the valve. The second state occurs when the pressure downstream of the valve cannot be maintained and drops below the set pressure. In this case the valve moves to a fully open position. For the third state, the PRV acts as check valve. If there is more than one pressure regulating valve in a water distribution system then each device may be in one of three states. In computer codes, a guess is made to the status of each of the pressure regulating devices and the system is solved for to determine the flows and pressures. A check is then made to determine if the guesses of status are consistent with the results. If the assumed status of the device is inconsistent with the results the status is altered and the hydraulic solver is re‐run. This paper demonstrates with a simple example that has a combination of a pressure reducing valve and a flow control valve that many commonly available commercial programs and Government programs cannot properly model even the simplest of systems.

Select this Article		Analysis of Unsteady Flow in Networks Using a Gradient Algorithm Based Method Iftekhar Ahmed and Kevin E. Lansey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)41 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A gradient algorithm based method is presented for analyzing gradually varied unsteady flow in water distribution networks. Using a Newton‐Raphson solution technique, the algorithm simultaneously computes piezometric heads at nodes and flow rates in pipes for all points within the network. Comparisons are made with steady‐state extended period simulations to show the robust behavior of the model for a complex water distribution network. The benefits of using a gradient algorithm are its flexibility in coding, versatility in operational conditions, and its application to complicated water distribution networks. The computer program implementing the method is general, easy to use, and allows a dynamic analysis of complex looped and open water distribution networks.

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WATER DISTRIBUTION SYSTEMS ANALYSIS III: CALIBRATION OF NETWORK MODELS

Select this Article		System Calibration Sampling Design by Genetic Algorithm Roger W. Meier and Brian D. Barkdoll ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)42 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Most municipal water utilities use computerized numerical models of their water distribution systems for tasks such as planning expansions, sizing components, solving operations problems, and estimating operating costs. These models must be periodically calibrated to the existing system by imposing a known demand on the system, collecting pressure data at selected points, and adjusting the model parameters until the model predicts the same pressures. It is not currently possible to rationally design a data collection plan that yields the best calibration information given limited equipment and personnel. This research addresses the demand side of the calibration equation by using genetic algorithms to find the combination of open hydrants that causes water to flow at non‐negligible velocities through as much of the pipe network as possible. The genetic algorithm, built around the hydraulic simulation package EPANET, has been applied to a network model for a small town in Ohio and was found to perform well.

Select this Article		Analysis of Pressure‐Dependent Leakage in Water Distribution Systems Jonathan A. Stathis and G. V. Loganathan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)43 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Closed conduit water distribution systems normally operate under pressure. The pipe network of a water distribution system is designed to deliver water to specific withdrawal points with adequate flow and pressure. Normal demands for domestic and commercial purposes are usually metered to keep track of the amount of water used. Water leaving the treatment plant and entering the distribution system (called water produced) is a valuable commodity for utilities and water authorities. The return on the investment is earned by billing consumers according to how much water they use based on meter readings. Leaks or breaks in water mains contribute to significant losses of potable water that, in turn, translate into lost revenue.

Select this Article		Leak Detection and Calibration of Water Distribution Systems Using Transients and Genetic Algorithms John P. Vítkovský, Angus R. Simpson, M.ASCE, and Martin F. Lambert ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)44 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The use of genetic algorithm optimisation applied to solving engineering problems has gained popularity over the last 10 years. Applications to the design of water distribution systems based on genetic algorithm optimisation first appeared in the early 1990s. This paper starts out with a brief review of the past use of genetic algorithms applied to aspects of water distribution systems. Leak detection and calibration of pipe internal roughnesses in a network are important issues for water authorities around the world. Computer simulation of water distribution systems has become a routine task of water authorities and consultants. One of the big unknowns in developing these models is the condition of the pipes, especially if they are old. It is very difficult to obtain reliable estimates of the roughness height for each pipe in the system using steady state calibration techniques. Liggett and Chen at Cornell University in 1994 developed an innovative technique called the inverse transient technique. The technique is able to determine, from unsteady pressure traces at a number of nodes in the network, the locations and magnitudes of any leaks that are occurring and the friction factor for each pipe in the network. An alternative approach to solving the minimization problem is presented in this paper. Genetic algorithm optimisation is used. A population of solutions is generated with each string representing values of the decision variables that are to be found. These include the magnitudes of leaks at nodes in the network and friction factors for each pipe. A forward transient analysis is performed for each string in the population that represents different combinations of leak magnitudes and friction factors. The sum of the absolute deviations between the measured transient pressures and the pressures predicted by the numerical model are determined and are used to determine the fitness of the string. The smaller the sum of the deviations then the larger the fitness that is assigned to the string. The genetic algorithm operators that are used include tournament selection, crossover and mutation. A new crossover operator is introduced. The genetic algorithm optimisation technique that has been developed in the research is applied to an example network. The results are encouraging and compare favorably with the inverse transient technique.

Select this Article		Optimal Network Calibration Model Based on Genetic Algorithms Srinivasa Lingireddy and Lindell E. Ormsbee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)45 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Validity of a hydraulic network model depends not only on the accuracy of its physical and geometric data but also on the accuracy of certain parametric data such as pipe roughness coefficients and nodal demands. Difficulties associated with economical and reliable measurements for these parameters often dictate estimation of these parameters through model calibration. This paper describes an optimization approach to calibrate a network model for demand adjustment factors in the context of an extended period analysis. The proposed model obtains an optimal solution by minimizing a nonlinear objective function subject to a set of linear and nonlinear constraints using a powerful search technique based on a genetic algorithm. Application of the optimal calibration model on an example water distribution system demonstrates the efficiency of the proposed approach.

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WATER DISTRIBUTION SYSTEMS ANALYSIS IV: MODELS OF WATER DEM&S & LOSSES

Select this Article		Developing an Integrated Model for Water Distribution Systems Considering Both Distributed Leakage and Pressure‐Dependent Demands Fernando Martinez, Pilar Conejos, and Juan Vercher ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)46 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A practical model to integrate both leakage and pressure‐dependent demands in extended period simulation models of water distribution networks is proposed. Given the pressure relationship for both terms, their coefficients associated to each node and time period are obtained from a minimum data set, constituted basically by the global hydraulic efficiencies for delimited areas and other general parameters, all of them usually available for water companies. The main aim of the proposed model is to get more reliable results when simulations are carried out for new scenarios such as pressure reduction for leakage control, failure of critical components of the network (water treatment plant, pumping station, main trunk, etc) or restrictions during an extended drought. Important conclusions can be obtained from the new integrated model on leakage assessment and management policies.

Select this Article		Demand Modelling of Networks with Individual Storage Nemanja Trifunović, M.Sc.C.E. and Maher Omar Rushdi Abu‐Madi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)47 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Computer models of water distribution networks are modern tools, which have recently begun to be used in developing countries as well. This study investigates possible approaches to modelling networks with individual storage. Following different hydraulic patterns than the direct supply networks, these systems require a special way of demand modelling. Two possible options discussed are to model the individual household reservoirs as pressure related demand nodes, or as shallow tanks of large surface area (“equivalent reservoirs”), each representing a group of tanks. Both alternatives were tested on a network model of Tulkarm, a town of app. 60,000 inhabitants, in the West Bank area of Palestine, which represents a typical example of Middle‐East distribution networks. The results show that the approach with equivalent reservoirs offers a more realistic picture in the analysis of the system operation, though it requires a more complex model and consequently more information from the field than usually available. Having in mind the relevance of the systems with indirect supply in the region, the conclusions obtained suggest additional features which computer modelling software should possess.

Select this Article		Modeling Indoor and Outdoor Residential Water Use as the Superposition of Two Poisson Rectangular Pulse Processes Yeongho Lee and Steven G. Buchberger ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)48 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract We test the hypothesis that residential water use can be modeled as the superposition of two Poisson Rectangular Pulse (PRP) processes. One PRP process is a perennial high frequency signal representing indoor water use; the second PRP process is a seasonal low frequency signal that accounts for outdoor water use. A key issue is to identify the conditions under which indoor and outdoor water uses can be combined (and represented by a single lumped PRP process) or when they should be separated (and represented by two distinct PRP processes). Computer simulation illustrates some properties of the individual indoor and outdoor water demands and the combined PRP water demand process. Residential water use data from a community near Cincinnati are used to demonstrate the utility of the dual PRP hypothesis.

Select this Article		The Uncertainty of Demand in Water Supply Optimization Models Guhl Florent, Bremond Bernard, and Gilbert Denis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)49 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 24‐hour optimization models of a drinking water network that we use take account of the hourly demand from each consumption area. In this paper, we propose two methods enabling the stochastic aspect of that demand to be taken into account. The first of the two methods makes it possible to meet the least favorable case. The solution obtained offers considerable safety but entails high costs. The second method is based on the definition of the probability of meeting the classic constraints of an optimization model. It is more precise, and enables the network manager to choose his degree of safety. Neither of the two methods proposed requires extra computer time as determinist linear programs solved with the Cplex software translate them both.

Select this Article		Nonlinear Forecasting of Daily Inflow Using Neural Network Hyun‐Suk Shin, Tae‐Woong Kim, and Joong‐Hoon Kim ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)50 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The daily inflow has one of apparent nonlinear and complicated phenomena. The nonlinearity and complexity make it difficult to model the prediction of daily flow, but attractive to try the neural networks approach which contains inherently nonlinear scheme. The study focuses on developing the forecasting models of daily inflows to a large dam site using neural networks. In order to reduce the error caused by high or low outliers, the Back propagation algorithm which is one of neural network structures is modified by combining the regression algorithm. The study indicates that continuous forecasting of a reservoir inflow in real time is possible through the use of modified neural network models. The positive effect of the modification using regression scheme in BP algorithm is showed in the low and high inflows.

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WATER DISTRIBUTION SYSTEMS ANALYSIS V: REAL TIME MONITORING & ANALYSIS OF WATER QUALITY

Select this Article		Water‐Distribution System Modeling as a Tool to Enhance Epidemiologic Case‐Control Investigations: A Case Study the Dover Township (Toms River) Childhood Cancer Investigation J. B. Sautner, M. L. Maslia, M.ASCE, and M. M. Aral, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)51 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Agency for Toxic Substances and Disease Registry is conducting an exposure assessment for use in an epidemiologic study of childhood leukemia and central nervous system cancers that occurred in the period 1979 through 1996 in Dover Township, New Jersey. Groundwater contamination has been documented historically in public‐ and private‐supply wells. Therefore, there is the possibility of exposure through this pathway. Because the Dover Township area has been primarily served by public water supply that relies solely on groundwater, the EPANET water‐distribution model, integrated with spatial analysis technologies, is being used to reconstruct historical water‐distribution system characteristics and investigate the question of exposure. To assist in calibrating the model to the current system, pressure data were gathered simultaneously at 25 hydrants using continuous pressure recording data loggers during 56‐ and 82‐hour tests in March and August 1998, respectively. Data for storage tank water‐levels, system demand, and pump and well status (on/off) were also obtained. Historical information on the water‐distribution system configuration will be used to relate the case and control addresses to the areas historically served by the water‐distribution system. Based on system operation data, model simulations will be used to estimate the percent of water delivered to a specific location from each of eight points of entry to the water‐distribution system.

Select this Article		Optimal Supervision of Drinking Water Distribution Network Ph. Harmant, A. Nace, L. Kiene, and F. Fotoohi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)52 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In the context of the self supervision of drinking water distribution systems, network managers have to carry out regular sampling campaigns. These samplings give a selective overview of quality but may suffer from a lack of representativity. Considering that a rational approach of the choice of sampling sites would improve the control of the quality in the network, the CIRSEE has developed a new strategy of selection of sampling sites. This strategy is based on an algorithm derived from a publication of Lee and Deininger. Modeling of the hydraulic behavior of the network is a compulsory step to street optimal sampling points. A covering matrix, deduced from Piccolo® hydraulics modeling (developed by SAFEGE), defines the link between each network node. Afterwards, the algorithm selects the most representative points (for sampling or on line monitoring) in terms of consumption and of water degradation (function of pipe diameter and water retention time).

Select this Article		Monitoring of Water Quality in Distribution, Systems Using Optimized Models, On‐Line Sensors and Booster Chlorination Stations Laurent Kiene and Aude Hemery ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)53 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In order to control the possible risk of bacterial contamination, chlorine residual should be maintained everywhere in drinking water distribution systems. But it is also important to control the formation of disinfectant by‐products and to keep their level at the minimum. To achieve these two goals: maintain a certain concentration of chlorine and limit the formation of disinfectant by‐products, it is important to know the exact chlorine coverage and improve this coverage by implementation of booster chlorination stations. The objectives are first to develop a very precise model to predict chlorine consumption in distribution systems and second to apply this model to manage disinfectant residual in full size distribution systems by choosing booster chlorination sites and chlorine doses.

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WATER DISTRIBUTION SYSTEMS ANALYSIS VI: OPTIMAL SYSTEM DESIGN & OPERATION

Select this Article		Optimal Operation of Water Distribution Systems for Water Quality Purposes Ayse Burcu Sakarya and Larry W. Mays, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)54 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A new methodology has been developed for determining the optimal operation of water distribution systems for water quality purposes. The methodology is based upon describing the operation as a discrete time optimal control problem that can be used to determine the optimal operation schedules of the pumps in distribution systems. The solution methodology is based upon a mathematical programming approach resulting in a large scale nonlinear programming problem which can not be solved by using existing nonlinear codes. The solution of the optimization problem is obtained by interfacing a simulation code, EPANET, which solves the hydraulic and water quality constraints with a nonlinear optimization code, GRG2. Bound constraints on the state variables are incorporated into the objective function using the augmented Lagrangian and the bracket penalty methods. Three objective functions can be used in the model: (1) the minimization of the deviations of actual substance concentrations from the desired concentration values, (2) the minimization of the total pump duration times, and (3) the minimization of the total energy cost. The effectiveness of methodology has been tested using both hypothetical and existing water distribution systems.

Select this Article		An Optimal Design of Water Distribution Networks with Hydraulic Connectivity and the Genetic Algorithm Hyun‐Gon Shin and Heekyung Park, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)55 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In designing WDN against emergency situation, efforts must be exercised for optimization with two objectives ‐ maximizing reliability and minimizing cost. For such optimization, it is necessary first to quantify the reliability of WDN using a surrogate measure. Hydraulic Connectivity is selected as a surrogate measure in this study which indicates a probability that every demand node in a network is connected to at least one supply source. An optimization model using hydraulic connectivity and GA is formulated. Just for illustration, the optimization model is applied to the New York City water supply tunnel. The yielded optimal design is found to be superior to the least cost design obtained from the Quindry's linear program method by $4.145 million when the connectivity is 0.9818. It is also noted that this approach is able to explore the tradeoff between cost and reliability directly. This permits designers to design WDN based on more quantitative information regarding cost and reliability.

Select this Article		The Application of Simulated Annealing to the Optimal Operation of Water Systems Fred E. Goldman, M.ASCE and Larry W. Mays, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)56 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The operation of water distribution systems impacts the water quality in these systems. EPA regulations require that water quality be maintained at all points in the system including the point of delivery. Methods to optimize water system operations have been restricted to reducing costs related to pumping and costs related to sizing, construction and/or maintenance of piping while meeting customer demands, pressure limits, and tank operation restrictions. There have been few attempts to optimize water system operations for both hydraulic and water quality performance and they have been restricted to simplified systems. A new methodology that formulates the water distribution system problem as a discrete time optimal control problem was developed which linked the method of simulated annealing with EPANET for optimal operation of water distribution systems for both water quality and hydraulic performance. Most optimization techniques require the calculation of derivatives, response functions, or other methods that are limited to specific problems. Simulated annealing allows optimization for a variety of objective functions and can consider many modifications to operational conditions without reprogramming of the optimization procedure. The new methodology was applied to the North Marin Water District, Novato, California system which considered optimal pump operation for minimizing power costs while meeting hydraulic and water quality constraints.

Select this Article		Development of a Booster Chlorination Design Using Distribution System Models Michael E. Tryby and James G. Uber ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)57 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A mixed integer linear programming method is developed which provides locations and operating data for booster disinfection stations in drinking water distribution systems. The problem formulation is related to the general fixed charge facility location problem, requiring that a branch and bound solution procedure be used. Branch and bound, while time consuming, is reliable enough for practical application of the problem to real distribution network models. Results are demonstrated for a network operated by a utility in the eastern United States. The method is used to develop a comparison between preliminary booster station design alternatives.

Select this Article		A Multicommodity Formulation for Multisource Water Distribution Network Shu‐li Yang, Tzong‐Cherang Tsay, Yung‐Hsin Sun, and William W.‐G. Yeh, F.ASCE and Hon.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)58 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Importing waters from two different sources with different water quality, the Metropolitan Water District of Southern California imposes water blending requirements at certain control points in its regional water distribution system. These requirements ensure the satisfactory quality of the water downstream of the control points. To determine optimal water distribution while at the same time meeting blending constraints and minimizing water shortage, a nonlinear multicommodity flow model is here proposed. Solving the proposed model brings some computational difficulty which stems mainly from incorporation of the highly nonlinear perfect mixing conditions. The nonlinear problem is solved with either a projected augmented Lagrangian algorithm or a genetic algorithm. Results show that, although extensive computational time is involved, the genetic algorithm locates a solution closer to global optimum than does the projected augmented Lagrangian algorithm.

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WATER DISTRIBUTION SYSTEMS ANALYSIS VII: FEEDBACK CONTROL OF NETWORK HYDRAULICS & WATER QUALITY

Select this Article		Self‐Adaptive State Estimation in Water Distribution Systems François J.‐C. Bouchart ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)59 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A new approach to estimating the state of a water distribution network is proposed. This approach combines a neural network‐based state estimation model and a reinforcement learning model to guide the management and control actions needed to resolve errors in measurements or to stem uncontrolled demands (i.e., pipe bursts). The contribution of this study is that the methodology focuses on the identification of the most likely underlying cause of inconsistencies between measured and computed state variables. The approach is demonstrated by application to a water distribution network.

Select this Article		Modeling TCE Dynamics in Water Distribution Tanks Thomas M. Walski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)60 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The paper presents a method to determine the concentration of TCE in a water distribution tank given the influent TCE concentration and the tank fill and drain rates. It then shows how to approximate this solution in the EPANET model.

Select this Article		Design of a Feedback Controller for Water Distribution Systems Residual Maintenance Marios M. Polycarpou, James G. Uber, and Umang Desai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)61 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a parameter adaptive formulation for designing feedback control algorithms for regulating chlorine residuals in water distribution systems. The approach is based on approximating the input/output dynamic behavior of chlorine concentration between an injection node (input) and a monitored node (output) as a time‐varying, discrete‐time linear model with uncertain or unknown coefficients. These coefficients are estimated on‐line using parameter estimation methods, such as recursive least squares, and the generated parameter estimates are used for feedback control. This formulation leads to an indirect adaptive control scheme, where on‐line identification and feedback control are performed simultaneously. The proposed approach provides a method for handling multiple, time‐varying transport delays and uncertain decay constants without apriori knowledge of consumer demands.

Select this Article		Chlorine Levels in Water Distribution Networks: From a New Simulation Method to a Control Formulation Sophie Constans, Bernard Brémond, and Paul Morel ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)62 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Chlorine concentrations are one of the main standards used to assess the quality of the water supplied by a distribution network. Chlorine evolution simulators are already available, but network managers still need optimization decision support tools. We thus present a new control‐oriented calculation method for chlorine concentrations in distribution networks. It has been developed for any cyclical velocity distribution from an analysis of the characteristic curves of the concentration transport‐reaction equation over each pipe of a network. Numerical results compare with those of EPANET. Unlike classic algorithms, our method needs neither discretizations inside the pipes, nor the choice of initial conditions. Moreover, it is a first step towards controlling the concentrations. Indeed, the method yields linear relations between the concentrations at both ends of each pipe, taking explicitly the system's dynamics into account. These relations can then be used as constraints for an optimization problem the objective of which is to minimize the deviations from target concentration values.

Select this Article		“CLOCWiSe”: Constraint Logic for Operational Control of Water Systems Mietek Brdys, Tom Creemers, Hans Goossens, Jordi Riera, Anton Heinsbroek, and Zbigniew Lisiak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)63 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Management and operational control of water systems have to meet many requirements from different fields, in order to satisfy consumers with sufficient amount water of appropriate quality, in a robust, reliable, and cost‐effective way. Fulfilling this task requires solving on‐line complex, hybrid, combinatorial problems, dealing with inherent uncertainty of demands and quality, and asks for fast responses to unexpected emergencies. Traditional approaches of decision support can hardly cope with this complexity, because of the highly interactive nature of the problem that necessitates an integrated approach. Constraint Logic Programming (CLP), an innovative programming paradigm, appeared very fruitful in a project, called CLOCWiSe, by a consortium consisting of the authors' institutions, and financially supported by the European Commission. It allowed building a Decision Support System (DSS) for the drinking‐water world offering functionalities not present in existing applications in the field. CLOCWiSe breaks with a simulation‐based approach which generally leaves the combinatorial aspects of the problem to the user and has difficulties to deal with uncertain and imprecise information. CLP offers a highly expressive programming tool which efficiently solves combinatorial problems. The approach is to reduce the initially large domains of possible values for variables by making these domains consistent with the constraints that implement the properties of the problem elements. This reduction approach not only offers a very natural way to express human knowledge but is also very suitable for dealing with uncertainties and incomplete information. Expressing the management and control objectives and the problem properties in the form of constraints allows for fundamental mathematical integration of different aspects of the problem. CLP can then be used to derive an efficient problem solver. In this paper a basic description of CLP is given as well as the concepts used in CLOCWiSe.

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WATER DISTRIBUTION SYSTEMS ANALYSIS VIII: INFORMATION & DECISION SUPPORT SYSTEMS

Select this Article		Using Extended Period Simulation Models for Design and Operation Thomas M. Walski ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)64 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Extended period simulation (EPS) models have been somewhat unpopular because the huge amount of data they produced made it difficult to understand the results of an EPS run. With the coming of improved graphical output, use of EPS models is much more practical. Some practical examples of what to look for in an EPS run are presented.

Select this Article		Using Hierarchical Organization to Reduce Complexity in Water Distribution System Simulation Models Curtis White, Thomas F. Victory, and Larry Mulhern ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)65 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract When confronted with complex systems, people often create an organizational structure to help reduce the complexity. In science, engineering, biology and many other fields of endeavor, the structure chosen is frequently a hierarchical one. A hierarchy is readily understandable. Think of it as a set of “Chinese Boxes”, where containers nest inside each other. Each box can contain several smaller boxes, each of which can contain several smaller boxes, and so on. Common examples of hierarchies are the organization chart of a large corporation, the taxonomic classification of living creatures in biology, and the way books are cataloged in a library. Each proceeds from the general to the specific, from coarse overviews to detailed information. It is natural to approach the problem of investigating the behavior of a complex water system by looking at it from a hierarchical framework.

Select this Article		A Computerized Maintenance Management System for Water Systems René van de Looij ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)66 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Recently, there has been a lot of pressure on water management organizations to optimize all systems in their organizations. Maintenance as a system plays a key role in achieving organizational goals and objectives in the long term against competitive cost. In water management the maintenance of the water system is crucial but up until now no rational way of planning and budgeting maintenance has been thought up. If maintenance needs are to be analyzed then much information on water systems needs to be recorded. So far, parts of the information have been collected in several kinds of database. However, these data collections have not yet all been standardize. Standardization of information is important if a widely usable decision support system (DSS) which makes use of existing information is to be created. This is why the input part of the DSS was built for structured (standardized), automated, user‐friendly registration of management information that can also use existing information. This input part makes use of a geographic information system (GIS) because there is a lot of graphic data has to be linked to alphanumeric data. Existing databases and applications using standard interchange formats can be used. On top of the input part, a DSS is being developed for generating estimates, plans (bills of quantities) and maps for all types of users.

Select this Article		An Ontological Approach to Water Distribution Systems Management P. Costa, A. Esposito, C. Gualtieri, D. Pianese, G. Pulci Doria, and L. Taglialatela ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)67 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water distribution system management involves complex problems and needs reliable models of the water supply system. The rising complexity of the systems to be managed today has exceeded a certain threshold, beyond which it necessary to change the scientific paradigm that supports the management of these systems. On the other hand, it is clear that the type of information required is not, generically speaking, quantitative. For instance, the proper functioning of a water distribution node is guaranteed as long as the pressure falls within a certain range, and does not require a precise value for this parameter. Therefore, the manager does not need to know the exact value of the pressure; rather he needs only know if the data fall within the predetermined limits. Furthermore, the manager is interested in knowing if the different parts of the system are operating in compliance with the established standards or not. In particular the manager wants to know if the objectives for which the system was created are being constantly met or not and, if not, what measures have to be taken to correct the cause of the failure.

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WATER DISTRIBUTION SYSTEMS ANALYSIS IX: POSTERS

Select this Article		Application of an Expert System to Control Treated Water Distribution Simon Bunn and Shane Helms ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)68 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract New Plymouth District Council (NPDC), New Zealand, has implemented an Expert System to optimise the distribution of water from the water treatment plant to five bulk supply reservoirs. The Expert System receives live data from a SCADA system and uses a set of rules to control flow through the trunk mains while optimising production throughput at the plant. A linear program evaluates the changes in system demands, reservoir levels and flow patterns every three hours, then empirically predicts expected future patterns to produce an optimised flow solution. Variation in water demand due to weather is a major consideration. Demand generated by watering gardens on hot summer days can push the daily supply total up by 100% and can be three times a normal winter day. Storage capacity is limited to less than one summer day's supply if safe minimum levels are to be maintained. Peak demand far exceeds the maximum flow rates of the WTP. While peak flow from the WTP is maintained reservoirs run low during the day and fill overnight. Flow constraints in some of the trunk mains are a further complication to solve. In order to maximise the production capacity of the WTP, NPDC contracted Beca Carter Hollings & Ferner Ltd (BCHF) to provide an Expert System to optimise distribution of water. This paper details the formulation of the optimisation problem and issues associated with its integration into the real time control of the pumps and valves within the distribution system. The benefits obtained from the implementation of this integrated approach are provided and discussed.

Select this Article		Long Time‐Series Simulation of Water Quality in Distribution Systems Benjamin L. Harding, P.E. and Thomas M. Walski, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)69 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Dynamic models have largely replaced steady‐state models for simulation of water quality in distribution networks. Dynamic models provide a better representation of the time‐variant behavior of contaminants in distribution networks, particularly that arising from flow reversal in pipes. Dynamic modeling generally has been limited to periods of a day or a few days. This paper describes three modeling studies that used long time series analyses to characterize contamination in the water distribution system of a major city. The use of long time‐series analysis provides a continuous representation of the persistence of contaminants in reservoirs. It also facilitates the understanding of transient operational conditions that may influence the way contaminants are transported within the pipe network. The technique also lends itself well to statistical analyses of exposure. As described in this paper, the methodology is practical for researchers and practitioners using readily available hardware and software.

Select this Article		Modeling of Pressure Reducing Valves Revisited Lyes Khezzar, Saad Harous, and Mohamed Benayoune ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)70 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The problem of simulating the steady state of water networks is very well known. There are many papers that have been written about this subject Also there are software packages available for this purpose. However there is no explicitly described method to model the pressure reducing valves (PRVs). In this paper we present a detailed algorithm to simulate the PRVs.

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SEDIMENT MOVEMENT IN CLOSED STORM DRAINS

Select this Article		Estimating Sediment Movement in Drainage Structures Dennis L. Richards, P.E., M.ASCE and Michael E. Zeller, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)71 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Drainage systems must be designed to adequately convey both water and sediment. Design procedures for the conveyance of water through a structure are readily available, but procedures for quantifying sediment movement through structures are not well documented. This paper presents methods for estimating sediment movement through drainage structures and provides a design example illustrating application of the methods.

Select this Article		Storm Sewer Junction Hydraulics and Sediment Transport Stuart M. Stein, P.E., Xibing Dou, Ph.D., Edward R. Umbrell, and J. Sterling Jones, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)72 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Stormwater can carry substantial loadings of suspended solids into storm sewer systems. A potentially important issue associated with sediment transport through sewers is “shock loading.” This occurs when periods of low flow leave significant sediment deposits in sewers and manholes. A large event can then provide the energy to scour the deposited material and transport far more loading to a receiving waterbody than is generated from the land surface during the event. This could be a potentially critical issue in developing TMDLs since loading might be far greater than expected for large events, and lower than expected for small events. This paper will present the results of significant physical modeling research on energy losses associated with manholes and discuss how these losses might effect sediment transport. Additionally, a 3‐D hydrodynamic model was applied to various manhole configurations to qualitatively assess circulation tendencies and sediment movement within manholes.

Select this Article		Test Methods for Assessing Abrasion Impact on CSP Drainage Structures Brian C. Roberts, P.E. and J. P. Ault, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)73 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The National Corrugated Steel Pipe Association (NCSPA) in conjunction with the American Iron and Steel Institute (AISI) has recently completed a multi‐year effort to develop test methods for evaluating and assessing the impacts of abrasion on CSP coatings. This work is an extention of the previously developed NCSPA Evaluation Methodology for CSP Coating/Invert Treatments, developed by Ocean City Research. The program's major objectives comprise the development of test criteria, test methods, and/or test apparatus to qualify organic and metallic coatings to extend the service life of CSP inverts. This paper presents the test methodology and initial test results of the program.

Select this Article		Recent Results and Research Needs on Cohesive and Non‐Cohesive Sediment Movement in Drainage Systems Jacques W. Delleur ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)74 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A Task Committee has been established to study the problem of sediment movements in urban drainage systems and to make recommendations for new research and for design and modeling improvements. This paper is an initial part of this effort. Sediments can cause sewer blockage, surcharge early overflows and large pollutant discharges and their removal is costly. The review of the recent literature shows that most of the progress has been made in Europe and that fundamental and applied research and development in the United States is urgently needed. It is urged that the National Science Foundation and the Environmental Protection Agency resume funding for further fundamental and applied research and development in this field.

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WATERSHED & RIVER SYSTEM MANAGEMENT

Select this Article		Reliability in Natural Channels — Towards River Planning Md. Mafizur Rahman, N. Tamai, and Y. Kawahara ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)75 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract There have been many attempts regarding the prediction of flow in the channel. Nevertheless, attempts have scarcely been made regarding the reliability analysis in the filed of hydraulics engineering. So, traditional practice still is confined in providing some unique safety factor for all the locations along a river reach. In true sense all the locations of the river reach are not exposed to the same level of risk or uncertainty of being flooded. Again, at the same location of the river reach, the level of risk changes over time. These fluctuations are related to the hydraulic as well as the hydrologic factors. A detailed study is attempted to capture the pattern of this variation of reliability at a certain location of the river reach and the idea is extendable to the whole river reach for any number of sections. FOSM (first order second moment) method is utilized as a means of this analysis. The correlation of the parameters, which is to some extent a critical but the most realistic consideration, is also considered. The results are expressed in terms of very comprehensive and simple manner to facilitate their direct application in the filed by the river managers and the field engineers and not to mention the planners. The main attempt of the research is to find some means in order to find the most dominant parameters responsible for the safety as well as risk at an existing section.

Select this Article		Watershed Management: A Tool for Flood Mitigation in the Petra Area (Jordan) Radwan A. Al‐Weshah, PhD. and Fouad C. El‐Khoury ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)76 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Petra is located in the south‐west region of Jordan about 200 km south of Amman between the Dead Sea and the Gulf of Aqaba. Petra was carved in sandstone canyons by the Nabatean Arabs over 2,000 years ago. It is a major tourism attraction as its monuments are considered the jewels of Jordan. Floods pose a serious threat to the tourist activities in Petra as well as to Petra monuments themselves. To alleviate the impact of floods on tourism in Petra, different flood mitigation measures are proposed. The impact of these measures on flood peakflow and volume is evaluated. These measures include afforestation, terracing, construction of check and storage dams, as well as various combinations of these measures. A flood simulation model depicts reductions up to 70 percent in flood peakflows and volumes due to these flood mitigation measures.

Select this Article		Rio Salado Town Lake: From Concept to Reality, June 1999 Howard C. Hargis, P.E. and Chuck Pedri, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)77 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Salt River is normally dry as it cuts through the Phoenix metropolitan area (commonly known as the Valley of the Sun) bisecting the City of Tempe from east to west. A series of seven reservoirs, constructed in the early 1900's to supply water and power to the Salt River valley, store and divert all river flows to an extensive canal system except under flood flow conditions. As a result, the Salt River flood plain has been a neglected and ugly strip of land, subject to infrequent flooding, mining, and illegal dumping. In 1966, the Arizona State University College of Architecture, located in Tempe, conceived the idea of turning this neglected riverbed into a recreation area. The idea sat dormant for many years until the Rio Salado (Spanish for Salt River) Commission was formed in the late 1970's. In 1987, the concept of improving the Salt River through a Rio Salado Project was submitted to the voters of Maricopa County for approval. The Countywide Initiative failed at the ballot box in all jurisdictions except the City of Tempe.

Select this Article		Impact on Fishery and Navigation of SSFCDI Project in Bangladesh: Recommended Mitigation Measures GM Akram Hossain and Ainun Nishat ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)78 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Flood Control and Drainage (FCD) developments are in conflict with open water fisheries, which are dependent on inland water, bodies. These water bodies are the rivers, beels (low, depressed wetlands), haors (bowl shaped depressions), baors (oxbow lakes) and floodplains which go under water in monsoon months. The occurrence of flooding of the low lands and floodplains are of importance to fisheries, as these areas are rich nurseries and feeding grounds for the larvae, juveniles and fries of many estuarine and marine species of fishes and shrimps. Construction of FCD embankments have reduced the extent of inundated areas negatively affecting open water fishery resources. This study has been taken up to evaluate the impact of small scale flood control, drainage and irrigation (SSFCDI) project of Bangladesh Water Development Board (BWDB) on fisheries and navigation sectors. One hundred and twenty two subprojects were implemented under SSFCDI project of which thirty‐eight have created negative impact on fishery with an estimated annual loss of about 4,100 tons of fish worth Taka 123 million (US$2.6 million). Furthermore subproject interventions like embankments, water control structures and closures have blocked many channels used for internal navigation creating negative impact on boat communication. Eight subprojects disrupted internal navigation affecting farmers to transport their agricultural produces from field during harvest and affected income of professional boatmen and traders' community. Mitigation plan for fisheries included fish friendly/fishpass structures and supplementary stocking of fish in perennial water bodies (beels, baors, and lakes) and seasonally flooded floodplains in subproject areas. Mitigation plan for navigation included navigation locks/boatpass across embankment to restore internal boat communication. The study recommended construction of seventeen fishpass structures and supplementary fish stocking in thirty locations. It has been estimated that fishery mitigation measures will increase open water fish production by about 10,800 tons annually. The study also recommended navigation lock/boatpass structures at 23 location to restore local boat communication and to rehabilitate boatmen and local traders' community. The plans were discussed with the stakeholders for social acceptability and checked for economic viability and were found socially acceptable and economically viable for implementation.

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TREATMENT PLANT DESIGN & EXPANSION

Select this Article		The Allentown Water Treatment Facility Expansion: Managing Expansion while Maintaining Operations James P. Lynch and Joseph J. Slivka ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)79 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In an effort to continue providing high quality and a reliable supply of drinking water, the City of Allentown, Pennsylvania embarked on a major upgrade project to its existing Water Filtration Plant (WFP). The challenges were many. In a period of rapid regulatory change, the City was faced with design and construction challenges that were to be addressed on a space‐constrained site while the plant remained in operation. The forward thinking approach of the City and the design/construction team assembled for the project was truly innovative. This paper will touch on some of the methods employed by the City to successfully achieve its goals for the plant and the project.

Select this Article		Environmental Systems Construction in Deschapelles, Haiti Bruce W. Berdanier, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)80 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Hospital Albert Schweitzer (HAS) was established in Deschapelles, Haiti in 1954 by Dr. and Mrs. William Larimer Mellon. The hospital is currently administered through the Grant Foundation Board of Directors. HAS was conceived, planned and built as a state‐of‐the art hospital for a tropical region. The environmental support systems of the hospital included: water collection, treatment, storage, and distribution; sanitary sewerage collection system; wastewater treatment; and solid waste incineration. The work planned for the subject project is for rehabilitating and replacing the HAS environmental support systems. Although these systems were well conceived and built in 1954, their typical useful design life is approximately 30 years. The staff has kept the systems operational with maintenance and design changes through the years, but major rehabilitation and replacement is now required for continued support of HAS operations and to protect the health of the staff and of the 600,000 residents of the region. Failing systems (such as the sanitary sewerage and wastewater treatment) currently are adversely affecting the health of the residents due to their impact on surface water sources. This project was initiated in the fall of 1995 with HAS staff members defining the need for the project.

Select this Article		Removal of Natural Organic Matter Fractions by Coagulation Taha F. Marhaba and Neeraj S. Pipada ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)81 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Both the proposed USEPA Disinfectant/Disinfection By‐Product and Enhanced Surface Water Treatment rules have provisions for minimizing the formation of undesirable precursors to disinfection by‐products (DBPs) in drinking water. Natural organic matter (NOM) in natural waters contains many of the precursors to the DBPs formed following disinfection of drinking water. DAX‐8 resin procedures were used to isolate and fractionate NOM into six fractions; hydrophobic acid, hydrophobic base, hydrophobic neutral, hydrophilic acid, hydrophilic base and hydrophilic neutral. The reactivities of the fractions to the formation of chlorination DBPs are discussed. Aluminum sulfate (alum) jar coagulation tests were performed to determine the optimum coagulation ranges of each fraction. Different levels of pH, fraction concentrations, and coagulant levels were used in the experiments. Given the reactivities of the individual fractions to the formation of selected DBPs (i.e. trihalomethanes, haloacetonitriles, haloacetic acids), one can optimize on the removal of problematic fractions. Hence, if minimization of DBP formation was solely due to specific removal of precursors, microbial inactivation issues would be resolved due to the fact that CT may be increased without an increase in DBP formation.

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GROUNDWATER MANAGEMENT: SOUTHCENTRAL ARIZONA

Select this Article		Status of the Regional Groundwater Flow Model of the Salt River Valley, Arizona Philip Jahnke ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)82 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Salt River Valley (Phoenix area) model is a USGS‐MODFLOW based groundwater flow model constructed by the Arizona Department of Water Resources (ADWR). The model simulates three‐dimensional groundwater flow in the regional alluvial aquifer system of the Salt River Valley and covers an area of about 14,500 square km (5,600 square miles). The model was developed as a hydrologic and water management tool capable of analyzing past and present groundwater conditions, and capable of testing future water management scenarios. The model has undergone a number of modifications since its publication in 1994. The most recent published runs (ADWR, Modeling Report 11) simulated projected water use scenarios through the year 2025. The model has been used to evaluate Assured Water Supply designations, which are required for municipalities/large developments in the Salt River Valley as a result of the Groundwater Management Act of 1980. These model runs estimated depth to water in the Salt River Valley for the year 2100, or approximately 100 years in the future. Several upgrades are in progress for the model, including the addition of the Interbed Storage Package to simulate the impacts of land subsidence, the addition of newly collected geologic and hydrologic data, replacement of the original River Package with the Prudic Stream Package, the addition of groundwater recharge sites, updating the calibration from 1991 to 1998, and development of a 1900 steady state model and a transient calibration period of 1900 to 1998. These upgrades should add new capability to the original model, and improve its usefulness as a tool to help municipalities and water providers improve future long range water supply planning.

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STORMWATER SYSTEM DESIGN & REPLACEMENT

Select this Article		Success Stories in Stormwater Retrofitting Gordon England, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)83 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In 1990 Brevard County created a Stormwater Utility under the Surface Water Improvement Division (SWID) for the purpose of retrofitting stormwater facilities for water quality and quantity benefits. Since that time over 200 retrofit projects have been constructed at a cost of over $11,000,000. This paper will discuss some of the types of projects implemented and the lessons learned.

Select this Article		Integrating Environmental Criteria into Alignment Selection Katherine Hon, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)84 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Alignments of infrastructure projects such as pipelines and roads are often selected using only engineering and economic criteria. Consideration of environmental issues is postponed until a selected alignment is evaluated in an environmental document or permit application. However, many affordable and buildable projects have been stopped by the environmental documentation or permitting process, or by public opposition. If environmental issues were integrated into the initial alignment evaluation and selection process, considerable effort could be saved. This paper discusses how natural resources and community issues can be integrated with typical design issues into a cohesive, engineering‐environmental evaluation process.

Select this Article		Combined Sewer Replacement Project: Village of Shorewood, WI Robert W. Carr, P.E., M.ASCE and James J. Lynch ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)85 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Another rainstorm occurs resulting in basement flooding. Meanwhile, community leaders struggle to respond to resident concerns and provide solutions that would resolve the basement flooding problems without causing financial difficulties for the community. In mature communities, combined sewers can spawn combined problems. Traditional solutions for combined sewer problems include the separation of the system into storm and sanitary components or the construction of large diameter relief sewers or tunnels. Unfortunately, the high costs of these solutions often deter action to resolve the combined sewer problems. This basement‐flooding scenario described the Village of Shorewood, Wisconsin, during the past twenty years. Following a 25‐year recurrence interval storm that occurred on August 27–28, 1995, the Village contracted with Earth Tech, Inc., formerly Rust Environment and Infrastructure to study the Village's combined sewer system and develop alternatives to alleviate the basement flooding. A strong commitment to communication and public input by the Village coupled with an objective approach by Earth Tech to consider all alternatives set the stage for the development of a final solution which would be technically sound, economically feasible and publicly understood and accepted. During the planning/engineering process, numerous public informational meetings served to provide basic input data as well as keep the residents informed of progress. Engineering information on the existing sewer system was collected and a flow monitoring program was conducted to verify both dry and wet weather flows. Computer modeling of the system's operating characteristics identified the nature and scope of sewer deficiencies. Analysis of alternative solutions resulted in a design to eliminate “bottlenecks” in the existing system, thereby maximizing the flow capacity of the entire system. The implemented improvements, completed in October 1998, has greatly reduced basement flooding problems at a cost savings over other alternatives. The paper will document the entire project process from the August 1995 storm event through the completion of the construction.

Select this Article		Prioritizing Sewer Line Inspection with an Expert System Margaret Hahn, S.M.ASCE, Richard N. Palmer, Ph.D., P.E., M.ASCE, and M. Steve Merrill, Ph.D., P.E. M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)86 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the development of an expert system that prioritizes sewer inspection. The expert system also identifies potential risks and their consequences, provides an appropriate inspection test method, and alerts the user when more information is needed to make an accurate determination. Prioritizing sewer inspection identifies the critical reaches of the system, reduces the number of inspections, and as a result, reduces both emergency repair and preventative costs. The belief network logic of the expert system is based on information to be provided by the sewer utilities often medium‐sized cities. The utilities will provide expert input on the probabilities of occurrence and relational dependencies associated with sewer line defects, condition assessment, and maintenance and rehabilitation procedures. This information helps assign the probability weights and relationships of the system's knowledge base. Feedback on prototype evaluations from the utilities will aid the validation process of the expert system development.

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APPLICATIONS OF ROUNDWATER OPTIMIZATION

Select this Article		Application of Mixed‐Integer Linear Programming Techniques for Water Supply Wellfield Management and Plume Containment at a California EPA Site Robert M. Gailey ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)87 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An evaluation of pumping alternatives was performed in support of remedial action planning for a groundwater cleanup in California. The cleanup was to remedy impacts to a water supply wellfield by a groundwater plume. The evaluation focused on assessing operational requirements for the wellfield in order to (1) accomplish groundwater plume containment and (2) meet water supply demands after treatment. Given the range of interests and perspectives represented by the various project stakeholders, it was clear that additional assessment would likely be required before the final details of the remedial action were agreed upon. Use of a streamlined and rapidly reproducible approach was key to reducing time requirements and successful evaluation of the pumping alternatives. This paper summarizes the results of applying mixed‐integer linear programming techniques to the evaluation of pumping alternatives. The benefits and potential pitfalls of using optimization techniques in consulting work are also highlighted.

Select this Article		Global Optimum Search Technique for Non‐Convex Groundwater Management Problems David W. Watkins, Jr., A.M.ASCE, Ximing Cai, S.M.ASCE, and Daene C. McKinney, A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)88 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A global optimum search technique is developed for solving groundwater management problems involving contaminant transport. Solving these problems is often complicated by the fact that, due to the presence of nonlinear equality constraints, convergence to the global optimum cannot be guaranteed. The proposed technique relies on linear approximations of some nonlinear terms and decomposition of the overall management problem into flow and transport sub‐problems for which globally optimal solutions can be found.

Select this Article		Multiscale Optimal Control of In Situ Bioremediation Yong Liu, Barbara S. Minsker, and Faisal Saied ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)89 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Multiscale methods have been demonstrated to be highly efficient techniques for solving partial differential equations. In this paper, the idea of applying multiscale computation to an optimal control model of groundwater in situ bioremediation is investigated. The optimal control model, which was developed in previous work, uses an optimal control method called successive approximation linear quadratic regulator to identify optimal well locations and pumping rates to minimize pumping costs. The model can be used as an aid in designing more cost‐effective aerobic in situ bioremediation, where injection wells are used to supply oxygen and extraction wells are used to contain the contaminant plume. The goal of this research is to improve the computational efficiency of the model so that complex field sites can be addressed. A spatial multiscale approach is presented in this paper. The spatial multiscale concept comes from discretization of the model domain with different mesh sizes. By solving the optimization on different numerical meshes and using bilinear interpolation operator to switch from the coarser mesh to finest mesh, significant computational savings can be gained. Both the convergence behavior and CPU time are presented for a case study under homogeneous conditions. The impact and choice of penalty weight when applying the multiscale approach are also discussed.

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PARTICIPATORY PROCESS IN WATER RESOURCES ACTIVITIES

Select this Article		Little Colorado River Watershed, Multi‐Objective Management George V. Sabol, PhD, P.E., F.ASCE and Chuck Williams, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)90 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Little Colorado River watershed covers virtually all of northeast Arizona extending into New Mexico, and contains numerous natural resources, including part of the Grand Canyon and the Petrified Forest National Park. The region is rich in cultural resources with several Native American Indian reservations, historic sites including Spanish and western expansion monuments, Route 66 and active missions, and is a major transportation corridor to the Nation via Interstate Highway 40 and railroads. Watercourses in the region, including the Little Colorado River itself, are characterized by long periods of drought and below average runoff followed by intermittent period of flooding that are often severe. Due to the semi‐arid nature of the area, soil and vegetation conditions, and the unique geology, the riverine systems are dynamic, resulting in flooding and sediment related problems that have major impacts on flood control works, transportation systems, development along floodplains, and natural and cultural resources. A system‐wide management approach is needed to achieve cost‐effective floodplain and sediment management while enhancing environmental aspects of the Little Colorado River watershed.

Select this Article		Proposed Restoration of Rio Grande in New Mexico Conrad G. Keyes, Jr., F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)91 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Restoration of the Rio Grande in parts of New Mexico has been suggested for sometime and environmental groups headquartered within New Mexico have recently emphasized the history of such. Two examples of potential restoration have been mentioned by the author with the help of information provided to members of the Rio Grande Compact Commission. The recovery plan of the Rio Grande Silvery Minnow could benefit Rio Grande restoration in the Middle Rio Grande Valley in New Mexico. Also the drain management planning for the Rio Grande Project may provide sufficient instream flows to increase the critical habitat for some wildlife species in the Mesilla Valley above El Paso, Texas. The coordination of each of these New Mexico examples have been described along with the potential of other actions that may affect the entire process of long‐term water management.

Select this Article		Making Stakeholder Values Work for Effective Watershed Management: A Case for Florida Regulators Timothy D. Feather, Ph. D., F. Dale Brown, Ph. D., and Michael T. Beezhold ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)92 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract To support improved and more efficient regulatory decision making, the U. S. Army Corps of Engineers (Corps) has been working with key stakeholder groups to identify central regulatory parameters in Florida. A watershed perspective was employed that addressed some of the fastest growing areas of Florida in highly sensitive environmental regions. In the case described below, approximately 1,500 square miles in southwest Florida were examined for the creation of an Environmental Impact Statement (EIS). The EIS framework was used by the Corps to bring local stakeholders together to develop and analyze alternatives for the study area in determining a reasonable and strategic balance between growth and the environment in the watershed. A carefully managed, professionally facilitated process was used to gain maximum input of the stakeholders. The group had to utilize a mix of quantitative information and best professional judgment to form its conclusions for the Corps. Lastly, geographic information systems (GIS) were used to guide some of the analysis and ultimately to plot the areas where solid agreement existed on how the development‐environmental balance should be formed.

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LARGE‐SCALE OPTIMIZATION IN CALIFORNIA WATER MODELING

Select this Article		A Statewide Economic Optimization Model for California: Modeling Process Brad Newlin, Jay Lund, Ken Kirby, and Mimi Jenkins ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)93 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A network flow optimization model has been developed to identify and assess economically promising institutional and infrastructure options for California's inter‐tied water resources system. The model, CALVIN, uses the US Army Corps of Engineer's prescriptive reservoir model (HEC‐PRM) and a newly developed graphical user interface. CALVIN optimizes statewide system operations based on agricultural and urban value functions and environmental constraints, allowing for the exploration of various infrastructure, market, and policy alternatives. This paper describes the development of the hydrology, network schematic diagram, economic inputs, graphical user interface, and alternatives evaluated by CALVIN.

Select this Article		Optimization Using OASIS with OCL™: California Application Jeffrey K. Meyer, Anthony P. Pulokas, Harold W. Meyer, and Daniel P. Sheer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)94 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An effective way to simulate large scale surface water systems is to use an optimization model. Some modelers in the water resources field have used linear programming to optimize the operation of a system over a period of record with a single optimization. OASIS with OCL™ works very differently. OASIS simulates a period of record by optimizing the operations for a single time step, then going on to the next time step. Modeling the very large and complex California water system using a monthly time step requires the use of several resources. One of which is OCL, short for operations control language, and it gives tremendous power to the modeler. The role of OCL is similar to that of a “scripting language” or “macro language” in other kinds of computer programs. OCL is not the source code for OASIS. Rather, it is a form of input to OASIS, in which the user enters special operating rules. The user w‐rites rules in OCL using various simulation commands. The formulation of the linear program is done using constraints and goal programming which describe the California system. The source code of the model never has to be modified or recompiled. OASIS also uses existing models or modules run in parallel to calculate delta outflow requirements during run time.

Select this Article		Modeling California's Water Resource Systems with CALSIM Armin Munévar and Francis I. Chung ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)95 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Simulation of large‐scale water resource systems for planning studies requires a flexible and efficient modeling tool to assist in the evaluation of rapidly changing alternatives. The California Department of Water Resources (DWR) has developed a general‐purpose river basin simulation model, CALSIM, that empowers users to quickly develop system representations and easily specify or modify operational criteria. CALSIM represents a fundamental change in the modeling approach used to simulate the operation of California's water resource systems, particularly the coordinated operation of the Federal Central Valley Project (CVP) and the California State Water Project (SWP). Model users now specify the system objectives and constraints as input, rather than embedding the simulation goals and logic in thousands of lines of procedural code as is common in traditional simulation models. A new modeling language, Water Resources Engineering Simulation Language (WRESL), has been developed to serve as an interface between the user and the linear programming/mixed integer linear programming solver, time‐series database, and relational database. The physical description of a water resource system and related operating criteria are entirely expressed in WRESL. The WRESL expressions can be compartmentalized to provide for a highly organized arrangement of logical units and to serve as self‐documenting modules. A number of built‐in features are currently available in WRESL, but the use of advanced computer science tools such as Java and JavaCC in the development of WRESL allow for rapid inclusion of additional functions and syntax. CALSIM is intended to replace the California Department of Water Resources' existing simulation model, DWRSIM, as well as PROSIM, another simulation model of the SWP/CVP system extensively used by the U.S. Bureau of Reclamation. However, the structure of the CALSIM engine is highly generic, such that the model can be applied to many other water resource systems.

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WATER SYSTEM PLANNING & ANALYSIS

Select this Article		Integrated Water Resources Planning and Management for Tehran Metropolitan Area in Iran M. Karamouz, F.ASCE, B. Zahraie, S. Torabi, and M. Shahsavarie ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)96 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Excessive demand for water due to growing population, agricultural, and industrial development along with the climate change and depletion of nonrenewable resources, intensities the need for integrated water resources management and optimal use of water resources as a sustainable source of energy. In this paper, a system approach to water resources management in Tehran Metropolitan Area, with its complex system of water supply and demands is discussed. Water resources in this region include water storage in Lar, Latyan, and Karaj reservoirs, Tehran aquifer, as well as water discharge in local rivers and in drainage channels (mainly supplied by urban runoff and wastewater). Framework of a Decision Support System for Tehran reservoir system, as a tool for managers and operators of this multifaceted system are also presented in this paper. The main priority is to provide over 800 million cubic meters of water per year for domestic consumption of 6.7 million population of Tehran. More than 60 percent of this water returns to Tehran aquifer through traditional absorption wells. Some part of this sewage is drained into local Firouz‐abad and Sorkheh‐hesar rivers and Yakhchi‐abad channel. A good portion of these low quality resources are used for irrigation in southern part of Tehran, resulted in a significant rise in water table and considerable environmental problems causing adverse social and sanitation predicaments. A wastewater collection and treatment project is underway and the effects of this project on water recharge of Tehran aquifer have been considered in this study. Reallocation of surface water resources, as well as an improved agricultural development scheme are also considered and discussed in this paper.

Select this Article		Technical Integration of Planning, Regulatory, and Operations Functions at the South Florida Water Management District Daniel P. Sheer, Ph.D., P.E., M.ASCE and Kent Loftin, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)97 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper examines the integration of a set of core functions which must be performed by the South Florida Water Management District (SFWMD). These functions include water supply, preparation of long‐term water management plans, granting permits for water and storm drainage use, and long‐term operations of the Central and South Florida Flood Control Project (C&SFFCP). These functions are carried out interdependently by the Planning, Research, Regulation, and Operations Departments with the underlying support of the Water Resource Evaluation (WRE) Department. These functions are examined together with the analytical tools which support them and the critical data which flows between them. The paper is based on analysis carried out by Water Resources Management Inc. (WRMI) for the SFWMD. The analysis is being revised and implemented on a continuing basis. This paper reflects conditions at the SFWMD as of 1996–7. Many of the problems identified in this paper are in the process of being resolved. This paper is presented as a case study of the kind of analysis required to ensure the logical consistency of the functions described. While it is rare (outside of Florida) that all of these functions are undertaken within a single agency, the authors believe that the logical rationale for moving data and coordinating methods between the functions will be similar even when multiple agencies are involved.

Select this Article		New Resource Developments and Water Company Leakage for UK Water Companies John A. Mawdsley ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)98 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Following water supply difficulties in droughts in the early 1990s, two of the regulators of the water supply companies within England and Wales ‐ the Environment Agency and Ofwat ‐ asked the companies to prepare water resource plans for the next 25 years. These have been produced in draft form following guidelines developed by the Environment Agency. The plans should follow an integrated resource planning approach that considers options to meet forecast deficits between supply and demand, including options to manage customer demand, options to reduce leakage losses from water company pipes, and new resource developments options. The potential impact of climate change on both the demand and the supplies had to be considered. The options chosen had to be based on a least cost economic analysis that included an economic assessment of the costs of the environmental impacts of the options.

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URBAN WATER INFRASTRUCTURE

Select this Article		Sediment Transport Modeling in an Urban Setting: Potrero Creek, Thousand Oaks, California David T. Williams, Ph.D., P.E., F.ASCE, Denny Tuan, P.E., M.ASCE, and James A. Turpin, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)99 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Ventura County Flood Control District (VCFCD), California, contracted WEST Consultants (WEST) to determine the trapping effectiveness of proposed in‐channel sedimentation basins for the purpose of reducing the sediment load entering Lake Westlake from Potrero Creek. Evaluation of the effectiveness was based upon an HEC‐6 sediment transport model that was provided by VCFCD. The existing HEC‐6 model was supplemented with additional geometry, updated sediment information then converted to HEC‐6T, a modified version of HEC‐6 developed by William A. (Tony) Thomas. This revised model was used to determine the effectiveness of various alternatives including optimum sedimentation basin configuration and location, the expected annual maintenance dredging, and the reduction in sediment delivered to Lake Westlake on an annualized basis.

Select this Article		Condition Survey of CSP Detention and Sand Filter Stormwater Management Systems Brian C. Roberts, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)100 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Stormwater management facilities constructed of corrugated steel pipe (CSP) have been used successfully throughout the United States since the 1970's. In recent years, these systems have gained wide acceptance as a preferred method for providing detention in urban areas. While the experience to date has been excellent, there has been no formal survey to assess the overall condition of these structures. This paper presents the methodology and preliminary findings from the National Corrugated Steel Pipe Association (NCSPA) Detention Inspection Program.

Select this Article		Durability Guide for Corrugated Steel Pipe Brian C. Roberts, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)101 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Corrugated Steel Pipe (CSP) has been used successfully in the United States for over one hundred years. While the vast majority of these installations are zinc coated galvanized CSP, numerous coatings and invert treatments are now available to extend the service life and environmental ranges of these products. This growing demand for CSP coatings requires additional guidance on coating selection, use, and service life prediction. In response, the National Corrugated Steel Pipe Association has developed Durability Guidelines. These Guidelines include: Product Usage Guidelines, Coatings Descriptions, Environmental Ranges, and Service Life Prediction for metallic and non‐metallic coatings.

Select this Article		Cost Minimization for Detention Basin System Design Bing Zhao, P.E., A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)102 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Detention basin is defined as a reservoir where water is stored for regulating storm water runoff. Gravity‐flow outlets are used to discharge the stored runoff. A detention basin system consists of a number of detention basins which are hydraulically connected. The conventional design method for a detention basin system is often trial‐and‐error and time‐consuming. The design by the conventional design method may not correspond to the minimal total cost for the detention basin system. The purpose of this study is to apply optimization techniques to find the optimal locations and design capacities for detention basins over a watershed such that the total cost for detention basins is minimized and the flood control objective is achieved. The total cost includes the land acquisition cost, construction cost, and maintenance cost. The flood control objective considered here is that the outflow peak discharge at the very downstream detention basin does not exceed an allowable value. A computer code is written by using MATLAB and MATLAB's optimization tool box to solve a numerical example to illustrate the methodology. The computer code can be easily adapted to solve other similar problems.

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SEDIMENT SOURCES & RESERVOIR SEDIMENTATION

Select this Article		An Alternative Approach to Determine Soil Slip Occurrences Paolo Bartolini, Ivan Nazzaretto, Mauro Di Veroli, and Juan B. Valdés ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)103 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Soil slips and slides are a common occurrence during heavy precipitation in many areas of the world. One of these places is the Ligurian region in northwestern Italy where, during intense precipitation in September 1993, more than 350 soil slips occurred in a small basin near the city of Genoa. Criteria for determining the occurrence of soil slips are usually based on estimates of average intensity and storm duration, to be compared with limiting values, usually represented by a line in a scatter diagram. These criteria, however, can only be used where a large amount of data makes the scatter diagram feasible; moreover, they do not take into account the degree of moistness of the soil. Thus they fail to explain some observed phenomena, e.g. soil slip occurrence under storms with lower total depth (i.e. lower average intensity) with respect to storms which did not produce soil slips. In this paper an alternative approach is presented in which the criteria for determining the occurrence of a soil slip is based on the comparison between soil slip producing and not producing events, their interpretation by using a conceptual model for infiltration, the use of a storm model; the final result is again a threshold line in an average intensity‐duration diagram, with specified values of the initial moisture condition and of the return period of the storms which produce soil slips. The approach was tested in the said basin near Genoa with satisfactory results.

Select this Article		The Growing Reservoir Sedimentation Problem in the U.S. Army Engineer District, Pittsburgh Werner C. Loehlein, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)104 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Most of the Pittsburgh District's sixteen reservoir projects were authorized by the 1936 Flood Control Act for the primary purposes of reducing flood stages and providing low flow augmentation for water quality control in the upper Ohio River basin. However, over the years sedimentation problems, seriously aggravated by erosion from extensive surface mining operations, has forced the District to gradually increase several project's minimum pool elevation. Much of the accumulated sediment is located immediately upstream of the dam. The sediment deposited at some of these reservoirs exceeds 30 feet in thickness for several miles in their lower portion. This paper will discuss the project's loss of storage due to sedimentation, the capability of handling a major flood, the District's attempt to remove the sediment, and the associated reservoir operational problems experienced during the sediment removal period.

Select this Article		Operation of Multiple Reservoir Systems to Control Sedimentation in Rivers and Reservoirs John W. Nicklow, Ph.D., P.E. and Larry W. Mays, Ph.D., P.E., P.H. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)105 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A new methodology is presented for determination of optimal reservoir management strategies that minimize sediment scour and deposition in multiple‐reservoir river networks. Consideration is given to adverse effects of sedimentation occurring in both reservoirs and rivers of an alluvial network. The problem is formulated as a discrete‐time optimal control problem in which a successive approximation linear quadratic regulator (SALQR) optimization algorithm is interfaced with the U.S. Army Corps of Engineers HEC‐6 sediment transport simulator. The simulation model is used to evaluate open channel flow hydraulics and sediment transport dynamics, while the optimization module strategically updates reservoir operation policies and solves the augmented control problem. System operating constraints imposed on stagewise reservoir releases and storage levels are incorporated into the objective function using a quadratic loss penalty function. The model can be used to minimize scour and deposition through an entire network or only at specified locations, and can be used to evaluate policies that alternatively maximize sedimentation. Capabilities of the model are demonstrated through applications to a hypothetical three‐reservoir river network and the Yazoo Basin river‐reservoir network in Mississippi. The resulting methodology serves as an effective decision support mechanism that can be used in the sustainability of rivers and reservoirs, as well as their associated benefits.

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FLOOD PROTECTION PROJECTS

Select this Article		Fool Hollow Spillway Rehabilitation Project Bob Davies, M.ASCE, P.E., Mark Larson, and Gerald Wright, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)106 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Fool Hollow Lake Recreation Area is located in Show Low, Arizona, in the White Mountains about 174 miles Northeast of Phoenix. The dam is owned and operated by the Arizona Game & Fish Department (AGFD). The original earthen dam and reinforced concrete spillway were completed in 1956 with the purpose of impounding a reservoir to provide recreational fishing and habitat for wildlife. The Fool Hollow reservoir has a 6,907,538 cubic meter (5600 acre‐ft) storage capacity to the top of the dam and a 3,947,165 cubic meter (3200 acre‐ft) storage capacity to the top of the spillway crest. The dam's spillway is detached from the dam and discharges into Bagnal Draw and then to Show Low Creek. The spillway has a reinforced concrete spillway 30.49 meters (100 feet) wide with an approach channel that is 97.56 meters (320 feet) in length. This paper summarizes and discusses the physical deterioration of the site since it was constructed, the need for a rehabilitation project, and the process that the project team used to plan and design a solution. The status of the project site near a recreation area and near habitat for endangered species mandated a careful planning and design process, one with the involvement and sanction of the USDA Forest Service (USFS) and other state and federal agencies.

Select this Article		The Flood Protection of Barbers Corners Christian A. Smith, M.ASCE and Delbert D. Franz, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)107 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 750 acre tract of land known as the Barbers Corners quarry in Bolingbrook, Illinois is subject to periodic inundation from higher magnitude flood events on the East Branch of the DuPage River (EBDR). The July 1996 storm event caused widespread flooding in 11 northeastern Illinois counties and millions of dollars in damages at the Barbers Corners quarry. The owners of the Barbers Corners quarry are in the process of acquiring permits to construct improvements to the quarry property which will reduce the potential for loss of life and economic damage at the quarry due to inundation from overbank flooding of the EBDR. This paper describes the establishment of the existing and proposed hydrologic and hydraulic conditions at the quarry and in the river utilizing the dynamic hydrologic and hydraulic FEQ computer program. This paper also compares the results for existing and proposed conditions obtained from the hydrologic and hydraulic analyses and examines the regulatory issues associated with permitting the proposed improvements.

Select this Article		Mobile Flood Protection Walls — Experiments and Reflections on the Risk of Flood Waves Caused by a Failure Rosi Liem and Jürgen Köngeter ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)108 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In Europe, many urban regions are strongly affected by flooding of rivers. To avoid the unpleasant appearance of high walls and levees along riversides, mobile flood‐protection‐systems have been designed. These systems are set up any time a flood is forecasted. Since risk assessment indicated possible danger to human beings caused by the propagating flood wave in case of a failure, it seemed to be reasonable to set restrictions on the dimensions of the wall elements. Therefore, at the Institute of Hydraulic Engineering and Water Resources Management (IWW) at Aachen University of Technology, experiments were carried out to obtain water levels and velocities within the propagating flood wave. In comparison to a dam break initial flow conditions, water levels and the amount of water passing the broken protection wall are varying. Due to the differences a modification of the main flow direction of the wave caused by the parallel main stream of the river and velocity profiles depending on the discharge of the river were noticed. By analyzing the obtained data with respect to the acting forces within the propagating wave as well as water levels, a required area of evacuation around the flood protection walls was derived depending on the dimensions of the wall elements.

Select this Article		Less Today Provides More Tomorrow Michael D. Heaton, P.E. and L. Steven Miller, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)109 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The South Phoenix/Laveen Drainage Improvement Project is the second of a two‐phase study sponsored by the Flood Control District of Maricopa County (FCDMC). The initial phase evaluated the magnitude of the storm water runoff and delineated the inundated area. This created a very large floodplain adjacent to the only natural drainage channel in the region, the Maricopa Drain. The delineation and hydrologic modeling was completed according to FEMA criteria. The purpose of the Phase 2 South Phoenix/Laveen Drainage Improvement Project was to identify flood control measures that would control the storm water runoff and provide flood protection for the future development in the region. The Phase 1 hydrologic modeling results were used as the basis of comparison between alternative plans developed by HDR. The Recommended Alternative was selected through an extensive evaluation process. The Phase 1 HEC‐1 model was revised in Phase 2 to reflect the features of the Recommended Alternative. Existing condition hydrologic models (10‐, 25‐ and 50‐year) were also developed to compare to a future condition model which included this project and also the County's 100‐year, 2‐hour retention policy. This comparison was then used to determine the design frequencies for the storm drains and detention basins.

Select this Article		Sacramento—A Case Study in Local Flood Control Implementation Paul T. Devereux, P.E. and Robert J. Cermak, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)110 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The City of Sacramento sits at the confluence of the Sacramento and American Rivers. Together, these rivers drain an estimated 4,820 km^2> (1860 square miles) including half the State of California and a portion of Oregon. As with most western cities in the 1800's, the City was located near the river for transportation purposes. Before there were highways, airports and even trains, the river was the source of life. It provided water to drink, irrigate crops, raise animals and a means of contact with the outside world. Yet as much as the river was needed to live, it could also be a deadly enemy. The entire Central Valley of California was known as an “inland sea” during many winters. Floodwaters would stretch for hundreds of miles from Redding in the north to the San Francisco Bay in the south and from the foothills of the Sierra mountains on the east to the Coastal ranges on the west. The Sacramento Area Flood Control Agency (SAFCA) is a joint powers agency which was formed by the City and County of Sacramento, Sutter County, the American River Flood Control District and Reclamation District 1000 following the major flood of 1986. By organizing a single regional flood control agency, the Sacramento area felt it had the best opportunity to secure a major Federal flood control project. It also provided a single unified local sponsor to work with the State and Federal government.

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NATURAL ATTENUATION MANAGEMENT ISSUES

Select this Article		Cost‐Effective Long‐Term Monitoring Design for Intrinsic Bioremediation P. Reed, B. Minsker, and A. Valocchi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)111 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The goal of this research is to develop a formal methodology for long‐term sampling and monitoring at intrinsic bioremediation sites. Intrinsic bioremediation couples the ability of indigenous microbial activity to decay contaminants with long‐term site sampling and monitoring to insure regulatory compliance. This methodology combines optimization and simulation to choose sampling locations that quantify the mass of contaminant while minimizing monitoring costs. It has three primary components: (1) groundwater fate‐and‐transport simulation, (2) geostatistical interpolation and global mass estimation, and (3) monitoring plan design using a genetic algorithm (GA). Contaminant concentrations at all potential monitoring locations are predicted using the Reactive Transport in 3‐Dimensions (RT3D) simulation package. Kriging subroutines are then combined with a GA to search for sampling plans that accurately describe the contaminant mass in the plume at minimal cost. For each sampling plan, the RT3D output is used by the kriging subroutines to estimate contaminant concentrations at all unsampled locations within the domain and the total mass of contaminant. Results show that this methodology is effective at both reducing sampling costs and accurately quantifying the mass of contaminant in the plume. The effects of various GA parameters on model performance are also presented. Extensions of this work in the future will include exploring the efficacy of alternate plume interpolation schemes, incorporating uncertainty, and testing other types of GAs.

Select this Article		Natural Attenuation of Solvents in Marsh Sediments J. J. Quinn, C. R. Yuen, and L. E. Martino ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)112 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Biological dechlorination of chlorinated organic compounds 1,1,2,2‐tetrachloroethane (TeCA), tetrachloroethylene (PCE), and trichloroethylene (TCE) under anaerobic conditions has been observed in many laboratory studies. However, few field studies have documented the degradation of TeCA under field conditions. This study provides field evidence that complete dechlorination of TeCA, as well as of PCE and TCE, to ethylene and ethane is occurring under anaerobic conditions in freshwater estuarine marsh sediments. The study area is located at J‐Field, Aberdeen Proving Ground, Maryland. PCE, TeCA, and TCE disposed of in an upland trench have leached into groundwater. The contaminated groundwater has migrated beneath and discharges to an adjacent freshwater marsh. Groundwater in the marsh sediments and underlying aquifer undergoes seasonal flow reversals: upward flow in the spring and downward flow in the summer and fall. The net result of this groundwater movement is an increase in the residence time for contaminated groundwater in the anaerobic, sulphate‐reducing, marsh sediments. Within the organic‐rich sediment, the TeCA, PCE, and TCE in the groundwater are anaerobically biodegraded to ethylene and ethane gases. This study provides evidence that, under favorable hydrologic conditions, a marsh can be an ideal site for complete dechlorination of TeCA, PCE, and TCE. Natural attenuation is, therefore, a promising alternative under certain conditions for low‐cost remediation of groundwater.

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INSTITUTIONAL MODELS FOR WATER MANAGEMENT

Select this Article		Keep the Boats Moving: Institutional Roles for Managing the Panama Canal Watershed Hal Cardwell, A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)113 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract When the new Panama Canal Authority (PCA) takes control of the Panama Canal on December 31, 1999, it will have to not only manage the engineering infrastructure of this “eighth wonder of the world” but will also be responsible for managing the lifeblood of this freshwater canal ‐ the watershed. Under the auspices of its Inter‐Institutional Commission for the Canal Watershed, the PCA will need to coordinate with multiple other national government institutions, non‐governmental institutions, the private sector and communities to ensure sustainable management of the natural resources of the watershed. It will need to educate the public about the function of the watershed, monitor the bio‐physical health of the watershed, and identify sustainable funding sources for its watershed management activities. As the Canal prepares to transfer, environmental professionals will be working to develop the policies and regulations to guide the operation of the Inter‐Institutional Commission, determining the relative roles and responsibilities in the watershed and answers to the all important “Who pays?” question. The paper presents this “work in progress” of engineers, ecologists, lawyers and politicians as they learn from history and look into the future to create the institutional structure to manage this water resource of international significance.

Select this Article		Water Management for the Twenty‐First Century Terence R. Lee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)114 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract There is a widespread and growing opinion among many of the professionals involved in water management, and among much of the public, because these opinions are widely expressed, that the world faces an imminent and ever more serious water crisis. This crisis is presented not just in the sense that water as a resource will become a more scarce commodity than it has been historically, but in the sense that the scarcity will be so marked as to cause serious economic, political and social repercussions. There are an increasing number of papers being presented to academic conferences, articles in the press and official reports which suggest that the threat of increasing water scarcity is becoming so grave as, a relatively balanced report from the United Nations states, to be “weakening one of the resources bases on which human society has been built.” Other reports, are less cautious and speak of increases in water scarcity leading to “conflicts among users, regions and countries.” In an absolute sense, however, even given climate change, water is not becoming scarcer. It is true that the amount of water is finite, but it is not only finite, it is inherently stable. We are not using up the water resource, because we cannot us it up. Water is not exhaustible, in the sense that coal, oil, any metal ore or other natural resource is and it cannot be used up. The amount of water available on earth has not changed for a very long period of time. Why then is there this concern? The concern with water scarcity seems to be due to the interaction of a multiplicity of very different factors. Among these factors the most important seem to be the idea that water is a finite and limited resource, a bureaucratic approach to water management, a concern with the continuing growth of the human population, the increasingly widespread economic change and growth in a globalized economy which is reflected in the expansion of industrial, urban and irrigation demands for water. There is also a strong Malthusian tendency expressed by many commentators which has been strengthened by the uncertainties introduced by the possibility of climate change due to global warming.

Select this Article		Institutional Arrangements Regarding Binational Plans for the Remediation of Water Quality in Great Lakes' Connecting Channels Bruce A. Kirschner and Anna Corro ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)115 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Great Lakes Water Quality Agreement of 1978 as amended calls for the Governments of Canada and the United States to develop and implement Remedial Action Plans in designated locations called Areas of Concern in order to restore and protect water quality in these locations. The binational connecting channels represent the most challenging institutional environment in which to develop and implement Remedial Action Plans. Institutional challenges in the connecting channel Areas of Concern have, in some instances, resulted in lengthy delays regarding the development and implementation of these plans. The authors have examined the various ongoing government activities focused on these Areas of Concern. Different institutional arrangements have evolved at the five connecting channels‐St. Marys River, St. Clair River, Detroit River, Niagara River, and the St. Lawrence River. These arrangements are compared and the apparently more effective arrangements are highlighted.

Select this Article		Water Resources Management in Developing Countries and the Role of World Bank I. Kaan Tuncok, Ph.D., P.E., Larry W. Mays, P.E., and John Briscoe ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)116 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water is an important element for life and a vital factor to economic and social development of countries. It carries an increasing importance for the developing countries in the Middle East, Sub‐Saharan Africa, and Central Asia; because of their rapid population growth, urbanization and limited renewable resources. A well‐defined framework to analyze policies and options would help determine water resources management policies for these countries. The World Bank, during the past three decades has contributed to the development of management tools suitable to the countries' needs for resources and capacities.

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ECONOMIC‐BASED SYSTEM OPTIMIZATION FOR CALIFORNIA WATER DISTRIBUTION SYSTEMS ANALYSIS

Select this Article		Economic Valuation of Urban Water Use for Large Scale Modeling Marion W. (Mimi) Jenkins and Jay R. Lund ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)117 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper explains how urban water values are developed from estimates of the own‐price elasticity of demand for residential use and from data on production lost due to water shortages for industrial use. These values are used in a large‐scale economic‐based optimization of California's state‐wide water system (CALVIN). The effects of season, climate, and consumption patterns (unique characteristics of a utility's water demand) are considered and accounted for where data are available to assess their impacts on demand. Demand functions that include residential, commercial, and government water use are generated by month and urban area over the range of typical urban water prices in California. Reduced industrial production as a function of water shortage is constructed by month and county from data for the Bay and Southern Coastal Areas of California. These functions are then converted to economic penalty functions that drive the optimization. Limitations of these urban water valuation methods for large‐scale modeling are discussed.

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INNOVATIVE STORMWATER MANAGEMENT APPROACHES FOR URBAN WATERSHEDS

Select this Article		Low‐Impact Development: An Innovative Alternative Approach to Stormwater Management Larry S. Coffman, Robert Goo, and Rod Frederick, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)118 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract To assist local governments in their efforts to develop more effective stormwater management programs. Prince George's County, Maryland Department of Environmental Resources (PGDER) in cooperation with the United States Environmental Protection Agency (EPA) has recently developed a guidance manual for an innovative alternative comprehensive approach to stormwater management referred to as Low‐Impact Development (LID). We believe that this new approach is a significant step forward towards advancing the state‐of‐the‐art of stormwater management and will be a valuable and useful tool for local governments in their efforts to control urban runoff. This new urban runoff control manual was adapted from PGDER's 1997 LID Design Manual. EPA provided grant funding to assist PGDER in their efforts to develop a general manual of LID'S principles and practices to make LID technology available to other local governments throughout the nation. Some practitioners have found LID'S site oriented micro‐scale control approach to be controversial, as it often conflicts with or challenges conventional stormwater management technology and site development practices. However, many have found LID'S source control techniques to be an economical common sense approach that can be used to better manage new development or retrofit existing development. It is hoped that the LID manual will help to stimulate debate on the state of current watershed protection technology and its future direction. This paper only briefly outlines the development of LID technology and its basic source control principles.

Select this Article		“Start at the Source”: Site Planning and Design Guidance Manual for Storm Water Quality Protection Tom Richman, ASLA and Jill Bicknell, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)119 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The site planning and design phase of land development projects presents the best opportunities for, and is critical to, reducing the impacts of development on the quality of the nation's waters. Unfortunately, most currently accepted site planning and design principles negatively affect water quality by increasing impervious surfaces and increasing the volume and velocity of runoff and pollutants that reach receiving waters. Recognizing the need for guidance in site planning and design, the (San Francisco) Bay Area Stormwater Management Agencies Association (BASMAA) published the document “Start at the Source ‐ Residential Site Planning and Design Guidance Manual for Stormwater Quality Protection” and a second edition in 1999 that also included guidance for industrial and commercial development. This manual, and its companion workshops, sought to educate planners, engineers, designers, builders, and public officials on the emerging practice of sustainable stormwater management. The manual communicates basic stormwater management concepts and illustrates simple, practical techniques to preserve the natural hydrologic cycle. It stresses the importance of minimizing impervious area and controlling and/or infiltrating runoff “at the source” rather than conveying it away for end‐of‐pipe treatment. The manual presents a menu of well‐illustrated choices for stormwater controls based on this design philosophy. This paper focuses on the effect of the manual on the current state of storm water management practice related to control of development impacts in the San Francisco Bay Area. It also discusses the obstacles to regenerative storm water systems and presents examples of successes and failures in site planning and design.

Select this Article		Low Impact Parking Lot Design Reduces Runoff and Pollutant Loads Betty Rushton, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)120 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An innovative parking lot design at the Florida Aquarium in Tampa, Florida, is being used as a research site and demonstration project to show how small alterations to parking lot designs can dramatically decrease runoff and pollutant loads. Three paving surfaces are compared as well as basins with and without swales to measure pollutant concentrations and infiltration. Preliminary results from eight storms indicate that for rain less than two centimeters, the basins with permeable paving have 60 to 90 percent less runoff than the basins without swales, and 40 to 70 percent less runoff than the other basins with swales. Larger rain events do not show any differences in runoff from the different paving types but basins with swales have 40 percent less runoff than basins without swales. Rainfall water quality and quantity are also evaluated and rain is found to be a significant input for inorganic nitrogen. Other water quality data show higher phosphorus concentrations in basins with vegetated swales, and higher metal concentrations in basins paved with asphalt rather than cement or permeable paving.

Select this Article		Integration of GIS and Optimization for Evaluating Urban Storm Water Quality Options James P. Heancy, David Sample, and Leonard Wright ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)121 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Urban storm water quality can be protected by maximizing the infiltration of frequent micro storms that account for the majority of the precipitation in urban areas. A proposed criterion is that the pre‐development initial abstraction of precipitation should not be decreased by development. The NRCS Curve Number Method is used to estimate the initial abstraction. Traditional approaches only partition land use into major categories such as medium density residential. Using GIS, land use can be measured down to the individual functional units such as roofs and driveways. Also, the critically important right of way area can be identified as a separate land use. Right of way constitutes a significant portion of urban land use and is responsible for a large proportion of the directly connected impervious area and pollutant loads. A linear programming (LP) model is used to find the mix of functional land use types that minimizes the cost of retaining the initial abstraction at its pre‐development level. This LP model uses land use information from the GIS as input data. The methodology is demonstrated on a case study to illustrate the procedure.

Select this Article		Field Testing of Ultra‐Urban BMP's Shaw L. Yu, M.ASCE, Xiao Zhang, Andrew Earles, and Mark Sievers ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)122 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The paper summarized recent results of field testing of “ultra‐urban”, or “space‐limited”, best management practices (BMP's). Beginning in July 1997, the University of Virginia has been testing a vault/reservoir structure installed at a bus maintenance facility in Charlottesville, Virginia. Two larger such structures were later installed in Warrenton, Virginia and were monitored between October 1997 and September 1998. Another ultra‐urban BMP, a bioretention area, was installed at a high school site in 1998 and has been monitored since November 1998. A total of 22 storm events were sampled at the vault/reservoir structure sites, and 4 storms have been sampled at the bioretention site. Water quality parameters examined included total suspended solids (TSS); total phosphorus (TP); chemical oxygen demand (COD), and oil and grease (OG). Results for the vault structure show that the smaller structure at the Charlottesville site removed on the average 68% of TSS; 53% of COD; 51% for OG, but only 7% for TP. The larger units in Warrenton removed 75% of TSS; 66% of COD; 79% of OG, and 44% of TP. Maintenance needs, however, is a major concern for such structures. Preliminary results collected at the bioretention site show 86% removal for TSS; 97% for COD; 67% for OG, and 90% for TP. More data are needed for the bioretention area assessment.

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STREAM STABILITY & SCOUR

Select this Article		Flood Proofing: Channel Stabilization Utilizing Soil‐Cement Randall P. Bass ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)123 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract During a six day period in the Fall of 1983 Tucson, Arizona received 17cm (6.7 inches) of rain (60% of the annual precipitation) which produced severe flooding along the Santa Cruz River. In 1993, a 14 day rainfall event in the same area produced flooding with a smaller peak but the flooding occurred for a longer duration. Each flood event subjected natural stream banks and soil‐cement protected banks to large velocities, long durations, and heavy bed loads. The effectiveness of the soil‐cement protected banks and drop structures was demonstrated during these floods and is now used quite extensively in the southwestern part of the United States. This paper discusses the evolution of the development of soil‐cement for water resources applications as used in bank protection and drop structures, the design considerations, and typical construction means and methods. Recent projects have been designed in sensitive areas that required greater emphasis on durability and appearance of the soil‐cement. Channel velocities are exceeding 7 m/sec (25 fps) and communities are demanding for the channel modifications to fit in with the natural surroundings. Example projects will be used to demonstrate the latest concepts in soil‐cement bank protection.

Select this Article		What Caused the Palm Canyon Wash Drop Structure Problem? Solving a Mystery and Finding Solutions in Palm Springs, California Marc A. Schulte, A.M.ASCE, David Smith, M.ASCE, and David T. Williams, Ph.D., F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)124 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Scour and stability problems on Palm Canyon Wash were threatening the structural integrity of a drop structure upstream of the Bogert Trail Bridge in Palm Springs, California. An incised channel had developed below the drop structure within the constructed watercourse, extending downstream of the bridge and threatening that structure as well. Our objectives were twofold. First, we needed to determine the cause of the degradation of Palm Canyon Wash. Once we had found the likely culprit, we would then propose a solution that would arrest the process and restore the channel to its intended condition. We proceeded along two lines of inquiry in our investigation of the cause of the degradation problem. First, we examined the energy‐dissipating effectiveness of the current drop structure upstream of Bogert Trail. The second possible culprit was the excessive mining of bed material from the channel in the early 1980's. Using hydraulic modeling and stable‐slope analysis, we concluded that the stream was seeking a new equilibrium, resulting an the incised channel within the wash. Once the incision reached the drop structure, the resulting loss in its energy‐dissipating effectiveness would serve to exacerbate the problem. Our stable slope analysis, corroborated by a comparison of recent survey data, told us that the incised channel was approaching an equilibrium state, but further degradation was still possible. In order to stop the progression of the degradation process, we proposed to install a second drop structure downstream of the Bogert Trail Bridge. Considering several designs, we determined that a sloping drop structure with a stilling basin and baffle blocks was the most appropriate, primarily because the flow at the drop was characterized by a low Froude number. We also made recommendations to increase the energy‐dissipation effectiveness of the upstream drop structure.

Select this Article		Hydrologic Analysis of Stream Stabilization and Stream Grade Control Structures Marshall Boyken, Ruochuan Gu, and Robert A. Lohnes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)125 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Grade control structures, namely sheet pile, h‐pile, rock sill, and concrete block weirs, are used extensively to control river channel degradation. Quantitative evaluations of these structures (such as in loess covered areas of western Iowa) can aid to determine their durability and provide guidance for future design. Although local geology and groundwater can affect field performance, streamflow rate is one of the most important factors because it represents the forces exerted on the structures. Structures that experiences different flows may perform differently, depending on the relationship between the stability of the structures and the external forces exerted on the structure, i.e., hydrologic and hydraulic conditions (flow rate and velocity). An objective evaluation of the durability and performance of grade control structures requires information on the flow that has passed through each structure. A comparison of historical flows to design flows is needed to correlate measured external forces and structure performance observed in field. In this study, a hydrologic analysis of stream stabilization and stream grade control structures is performed for drainage basins consisting of small streams and rivers in rural areas where no streamflow gauging stations are available. The reconstruction of streamflow history provides an estimate of the maximum historical discharge that can be compared with the design discharge. Historical flows are determined from precipitation data and drainage basin characteristics, using a computer simulation program (HEC‐1). The model is validated using field data from western Iowa and can be applied to ungaged sites in other regions.

Select this Article		Safety Assessment of Grade Control Structures Carlos C. Carriaga, PhD, P.E. and Patricia Q. Deschamps, P.E., R.L.S. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)126 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A procedure was developed to evaluate the performance of grade control structures for the presence of dangerous hydraulic jumps known as ‘rollers.’ Formation of ‘rollers’ around vertical drops, weirs, and spillway structures is known as the principal cause of many drowning deaths in the United States. A validity test was performed to check the credibility of the proposed analytical procedure. This is achieved by using results of physical model tests found in the literature with results evaluated from the use of the analytical procedure. The hydraulic analysis performed on the existing grade control structure showed that ‘rollers’ do occur for a wide range of flood discharges tested. Because of potential hazards and threat to public safety, recommendation was made to modify the existing grade control structure.

Select this Article		Kentucky Bridge Scour Program W. Ron Gardner, P.E., James R. Stahl, P.E., and Stephen R. Noe, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)127 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In 1995, the Kentucky Transportation Cabinet (KYTC) started working with Ogden Environmental and Energy Services (Ogden) to establish a risk assessment approach to analyze bridge scour. This program integrated the best ideas from other state scour programs, and the experiences of KYTC and Ogden. KYTC was responsible for 8,713 bridges over water at the outset of program implementation.

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RESERVOIR OPERATIONS DURING FLOODS

Select this Article		Conducting a Virtual Flood for Devils Lake, North Dakota William Werick, Richard Palmer, and Andrew Wood ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)128 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the process of planning and conducting a Virtual Flood of Devils Lake, North Dakota. A Virtual Flood is a workshop in which interested parties can use computer simulations to test flood fighting measures. Devils Lake, a terminal lake located in North Dakota, has risen over 20 feet during the last four years. This increase in elevation has generated approximately $120 million in damages and mitigation efforts. In 1995, 1996 and 1997, the lake rose to levels hydrologists had said were possible, but improbable. Levees were built and then raised, and raised again. The St. Paul District of the US Army Corps of Engineers and the State of North Dakota are studying a plan to pump lake water into an adjacent river basin. The first analysis showed the costs for the pump were much greater than the benefits, but many distrusted the analysis because the economic benefits of the pumping plan were based on the estimate of probable future lake levels. The question in many peoples' minds was, if we were forecasting lake levels better, would the benefits exceed the costs? Late in 1997, the Corps, the state, and stakeholder groups agreed to participate in a Virtual Flood of Devils Lake. The goal of the Virtual Flood of Devils Lake, held on March 11, 1998 in Grand Forks, North Dakota, was to develop a common understanding among stakeholders and management agencies of the effectiveness of a proposed artificial outlet in reducing flood damages. The Virtual Flood demonstrated that the outlet would likely not reduce lake levels enough in the next several years to avoid other flood fighting costs, such as the construction of levees and road raises.

Select this Article		Flood Control Optimization Using Mixed‐Integer Programming David W. Watkins, A.M.ASCE, Dustin J. Jones, and David T. Ford, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)129 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract To support flood control planning and operations studies by the U.S. Army Corps of Engineers, the Hydrologic Engineering Center has developed a mixed‐integer linear programming model for flood control optimization (FCMIP). Given a set of inflow hydrographs at various locations in a river basin, along with flood damage functions at key control points, the model makes reservoir release decisions that reduce flood damage consistent with the goals and priorities of system operation. Applied within the framework of implicit stochastic optimization, the model can help the user infer an improved operating policy for an existing flood control system or screen structural alternatives for system enhancement. This paper describes the mathematical formulation, solution technique, and expected benefits of the model.

Select this Article		Simulations of Flood and Inundation Affected by Pumping‐Station and Flood‐Gate Operations Wei‐Hsien Teng, Ming‐Hsi Hsu, Chung‐Jen Lu, and Tsang‐Jung Chang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)130 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The surface inundation under influences of pumping‐station and flood‐gate operations has been simulated. The pumping‐station and flood‐gate systems affect water flow discharge between the river and drainage basin. A numerical model, consisting of a one‐dimensional dynamic‐flood routing for a river and a two‐dimensional zero‐inertial overland flow model for a drainage basin, is developed to simulate river flow and basin inundation during flood. The study area, located in the western part of Metropolitan Taipei city is selected for simulation. The rainfall data, geographic features, capacity of pumping‐station and flood‐gate operations are input for numerical simulations. The field recorded data of Typhoon Herb event in 1996 is used for the calibration of the numerical model. The model is also applied to simulate the inundation in the study area under the full operation of pumping‐station and the exact closure if flood‐gate.

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GROUNDWATER ISSUES IN POLICY & DECISION MAKING

Select this Article		Disposal of Oil Field Wastes and NORM Wastes into Salt Caverns John A. Veil ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)131 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Salt caverns can be formed through solution mining in the bedded or domal salt formations that are found in many states. Salt caverns have traditionally been used for hydrocarbon storage, but caverns have also been used to dispose of some types of wastes. This paper provides an overview of several years of research by Argonne National Laboratory on the feasibility and legality of using salt caverns for disposing of nonhazardous oil field wastes (NOW) and naturally occurring radioactive materials (NORM), the risks to human populations from this disposal method, and the cost of cavern disposal. Costs are compared between the four operating U.S. disposal caverns and other commercial disposal options located in the same geographic area as the caverns. Argonne's research indicates that disposal of NOW into salt caverns is feasible and, in most cases, would not be prohibited by state agencies (although those agencies may need to revise their wastes management regulations). A risk analysis of several cavern leakage scenarios suggests that the risk from cavern disposal of NOW and NORM wastes is below accepted safe risk thresholds. Disposal caverns are economically competitive with other disposal options.

Select this Article		Eastern Interstate Water Compacts Joseph W. Dellapenna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)132 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract States have often sought to solve problems that cross state lines cooperatively without surrendering control entirely to the federal government. The legal instrumentality for such cooperative action is the interstate compact. Many compacts have dealt with problems of interstate water management. In western states, the emphasis has been on simple allocation of scarce water resources, without much concern about ongoing cooperative management. Eastern states have followed a very different path, emphasizing the need for just such ongoing cooperative management in order to maintain the quality of the waters rather than to allocate their benefits. Most eastern compacts, however, provide only for the exchange of information and for consultations on mutual problems. The Delaware River Basin Compact provides a very different model, combining the state and federal governments in a commission authorized to make far‐reaching regulatory and operational steps in order both to preserve and protect the water environment of the basin and to allocate the benefits of the waters of the basin to individual and public entities within the basin. This paper begins with a survey of the law of interstate compacts generally. It then compares the usual patterns of interstate water compacts in the west and the east. It then proceeds to describe in some detail the provisions and workings of the Delaware River Basin Compact. It continues with a brief survey of the Great Lakes legal system as a model of what I call the “we'll keep in touch” sort of compact that provides the template for most eastern interstate water compacts. Finally, it closes with a brief discussion of the efforts to craft a workable compact in the southeast of the United States to manage the waters of the rivers shard by Alabama, Florida, and Georgia.

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INTRASTATE REGULATIONS IN TRADITIONALLY RIPARIAN AREAS

Select this Article		Surface Water Withdrawal Allocation Systems for Traditionally Riparian Areas J. Wayland Eheart and Jessica J. Cragan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)133 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In recent years there has been an increasingly apparent need for water regulations in states traditionally under the Riparian doctrine. Several states have passed water laws to control withdrawals from streams. Few, if any, however, have set up consistent, formulaic, and reproducible methods for allocating water to users. This paper presents several options for such allocations, examining each in detail and offering numerical examples that compare each on the basis of economic efficiency and effectiveness in maintaining critical streamflow standards. In keeping with the historical features of the riparian doctrine, all methods that are viewed as being capable of implementation are based on sharing shortages and surfeits, so that the amount of water a given user is allowed to withdraw increases and decreases with the amount of water flowing in the stream. The paper first describes the options for allocation and then, after briefly summarizing methods for doing so, presents the results of a study to determine the efficacy of two alternative allocation methods. The findings presented here are the results of a study to assess the vulnerability of Midwestern streams to climate change and, especially, surface supplied irrigation spawned by such climate change. Accordingly, there is a focus on irrigated agriculture as a major consumer of surface water.

Select this Article		Balancing Tests in English Water Law R. Peter Terrebonne ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)134 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract It is said that rules governing water rights in the eastern United States are based upon English common law. This paper compares balancing tests in English water law to the American test of balancing the gravity of the plaintiff's harm against the utility of the defendant's conduct. The American reasonable use test was explicitly rejected by English courts.

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UNCERTAINTY IN HYDROLOGIC SYSTEMS

Select this Article		Estimating Uncertainty in Hydrologic Model Predictions Kathryn Goodwin, Carlos Rentas, Kevin Lansey, Bisher Imam, and Soroosh Sorooshian ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)135 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Parameters for physically based hydrologic models are typically developed based upon user judgement and look up tables. Parameter estimates inherently contain a certain amount of error that affect the reliability of hydrologic models. By considering these estimates to be random variables, the output of the models in which they are used must also be considered as uncertain. While sensitivity analysis provides information about how much the output changes with small changes in a particular input parameter, uncertainty analysis goes further. It provides the statistical properties and an estimate of the statistical distribution of the output from the statistics or distribution of the input. Thus, the error introduced into model results by uncertain model input parameters can be assessed quantitatively.

Select this Article		Analysis and Control for Hydrosystems under Uncertainty Bing Zhao, Ph.D., P.E., A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)136 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Hydrosystems are subject to uncertainty. This paper will attempt to answer three challenging questions associated with hydrosystems under uncertainty. The first one is how to perform model calibration and model validation. The second one is how to quantify uncertainty and risk. The third one is how to reduce uncertainty and risk. The proposed methodologies are based on optimization‐based model calibration, statistical validation, bootstrap‐based storm resampling, constrained Monte‐Carlo simulation, probabilistic point‐estimate, and feedback control. The proposed methodologies will be applied to a rainfall‐runoff hydrosystem in Taiwan and the United Kingdoms, and an estuary hydrosystem in Texas, USA. The methods discussed in this paper can be applied to other hydrosystems.

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ANALYSIS OF IMPACTS FROM URBAN RUNOFF IN SMALL WATERSHEDS

Select this Article		Assessing the Effectiveness of a Stormwater Pollution Prevention Program in an Industrial Catchment Dan Cloak, P.E. and Jill Bicknell, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)137 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 1996 handbook Environmental Indicators to Assess Stormwater Control Programs and Practices describes the use of 26 indicators within 6 general categories — water quality, physical/hydrological, biological, social, programmatic and site‐specific — to measure the success of stormwater programs. The handbook also suggests a methodology for using the indicators to identify problems within local watersheds and for assessing, reevaluating and improving stormwater management programs. With grant assistance from the Water Environment Research Foundation, the Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP) is demonstrating this methodology at a watershed scale (Coyote Creek watershed, Santa Clara County, California) and at a smaller, more defined scale, that of a 28‐acre industrial catchment in the City of Santa Clara, California (one of SCVURPPP's participating agencies). The focus of this paper is the application of the indicator methodology to this industrial catchment (Walsh Avenue). Samples of runoff from the Walsh Avenue catchment collected during 1988–1992 were found to have elevated concentrations of zinc, copper and lead, which caused acute toxicity in indicator organisms. Currently, SCVURPPP is documenting the City of Santa Clara's pollution‐prevention outreach to local businesses (Indicator #18), evaluating the number of BMPs installed and maintained (#22), reviewing industrial stormwater permitting and compliance records (#23), and compiling records of industrial inspections (#11). During the 1998–1999 rainy season, runoff from the catchment will be monitored for water‐quality constituents (Indicator #1), including heavy metals, and for toxicity (#2). Analysis will include a calculation of non‐point source loads (#3). This suite of indicators should allow the SCVURPPP to assess its programmatic effectiveness (e.g., are BMPs being implemented?) and may also allow an assessment of the program 's effectiveness in improving runoff quality.

Select this Article		Integrated Stream Stability Assessment and Water Quality Modeling for a Watershed Study Michael Clar, Donald Outen, and Eldon Gemmill ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)138 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the current approach adopted by Baltimore County, Maryland, to integrate stream stability assessment and water quality modeling for a comprehensive study of the Patapsco River Watershed in south‐western Baltimore County. This watershed of 3,687 square kilometers (1,424 square miles) drains three urbanizing counties in the Piedmont physiographic province and empties into the Coastal Plain, Baltimore Harbor and the Chesapeake Bay. Land uses cover a range from commercial‐industrial to residential, rural, institutional, and agricultural. The subject watershed study covers an area of 130 square kilometers (50 square miles) and 283 kilometers (176 miles of streams. Historically watershed studies began as primarily hydrologic/hydraulic studies focused on drainage structures and flood control. Later, in response to our growing awareness for water quality issues, water quality models which identify pollutant sources and calculate pollutant loadings were added to the scope of watershed studies. Continued concern for the accelerated degradation of stream channels, the accompanying loss of habitat values, and the problems associated with accelerated stream channel erosion and downstream sediment deposition have convinced Baltimore County to adopt methods to integrate stream stability assessment with water quality modeling and hydraulic analysis in watershed studies.

Select this Article		Performance of Stream Restoration Efforts in Small Watersheds James W. Gracie, A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)139 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A number of stream restoration efforts have been carried out in small watersheds in Maryland for the past ten years. Nearly all have been deemed successful based upon evaluations of the project immediately after construction has been completed. The success of a project that has attempted to restore stability and reduce erosion should be evaluated on the basis of long term monitoring to insure that stability is an enduring condition. Stability is defined as a dynamic condition in which dimension, pattern and profile are stable and neither aggradation nor degradation is occurring. The goal of virtually all of the restoration projects described in this paper was to reduce high sediment supply from bank and bed erosion and to increase sediment transport, thus restoring a condition of equilibrium between sediment supply and sediment transport. Most of the impacted streams in small watersheds in Maryland have experienced a dramatic increase in sediment supply as the channels enlarge to accommodate an increase in flow regime caused by land development. When this increase in sediment supply exceeds the capacity of the stream to transport it, depositional features form which in turn can cause more erosion. This process follows a positive feedback mechanism. The most apparent feature of steams in this condition of disequilibrium is a very large component of fine sediment. Particle size distributions of bed material show a bimodal distribution with most of the particles in the fine sand range. A successful restoration effort should result in a decrease in the fine fraction of this bed material size distribution. This paper presents a monitoring protocol and evaluates performance of several projects which have had varying degrees of success. Monitoring results are presented for up to five years on some projects. Biological monitoring results are presented for some of the projects.

Select this Article		Receiving Water Quality Monitoring for Assessment of Storm Water Runoff Impacts: A Case Study Scott M. Taylor, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)140 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A receiving water quality monitoring program was developed to measure beneficial use impacts resulting from toxicity in storm water runoff. Significant toxicity has been identified through field sampling in San Diego Creek, the primary tributary to Upper Newport Bay in Orange County California and in Upper Newport Bay. The goals of the water quality monitoring program are to determine the persistence, fate and significance of the aquatic toxicity in the receiving water. The program is being completed in two phases reflecting the finding from two EPA grants. A 205(j) planning grant is providing resources for characterizing the toxicity in the receiving waters using standard EPA tests. A 319(h) implementation grant is providing resources for determining the source of the toxicity in the watershed, and ultimately, to develop source control BMPs for the constituents identified as a part of the planning portion of the program. The initial receiving water testing began in the fall of 1997. To date, there is toxicity to Ceriodaphnia (freshwater zooplankton), Mysidopsis bahia (marine zooplankton), and, in an isolated case, Pimphales promelas (fathead minnow larvae). About one‐half of the toxicity has been identified through directed Toxicity Investigation Evaluations (TIEs) as resulting from organophosphorous pesticides. The remaining toxicity was not identified through a conventional TIE. Additional investigation is currently underway to identify the compounds responsible for the unidentified portion of the toxicity and the significance of the toxicity in the Bay to aquatic life.

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CHANNEL IMPROVEMENTS

Select this Article		Optimization Approach to Stable Channel Design Carlos C. Carriaga, Ph.D., P.E. and Larry W. Mays, Ph.D., P.H., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)141 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A procedure to design stable channels is proposed in this paper. This procedure employs the concept of optimization, which requires the definition of an objective function and the consideration of governing system equations that describe the flow hydraulics involved, the bed erosion and mobility in the channel, and system requirements that set the design criteria. The advantages of this procedure are presented against the advantages of conventional procedures. As a case study, an existing project that was analyzed using conventional methods is analyzed using the optimization procedure.

Select this Article		Minimizing Errors Due to Cross‐Section Point Reduction Quentin Travis, P.E. and Burke Lokey, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)142 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The geometric and hydraulic effects of eliminating cross‐section data points were analyzed for a major floodplain study in Arizona. The subject of the study was a very wide wash, and the cross‐sections for the study were computer generated, which resulted in ten cross‐sections with a number of data points beyond the 100 point maximum allowed by HEC‐2. Therefore, a reduction paradigm was developed to eliminate the least significant data points. To analyze the impact of this reduction, a variety of statistical and hydraulic parameters were calculated. From these parameters, a differential analysis was performed to estimate the error to the calculated high‐water depth. The analysis indicated that the reduction paradigm reduced the cross‐section data points without significant effect on either the cross‐sectional geometry or the estimated high‐water depth. Despite the fact that some cross‐sections were reduced by nearly 50% of their original data points, the maximum estimated error to the high‐water depth was only 2 mm (0.006 ft).

Select this Article		Tug Fork Channelization, Floodplain and Wetlands Mitigation: Lessons Learned David Dee, Jr., P.E., M.ASCE, Neal Carte, and Gregory Hoer, ASLA ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)143 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The West Virginia Department of Transportation Division of Highways (WVDOH) used a two‐level channel excavation concept to mitigate the hydraulic impacts of relocating U.S. Route 119 in the floodplain of the Tug Fork river. The proposed alignment placed much of the proposed roadway embankment within the floodplain of the river. The encroachment reduced the available conveyance of the Tug Fork by as much as one half at some locations. Over 800,000 cubic yards of channel and floodplain excavation proved to be the only alternative, of a dozen considered, that would provide the necessary conveyance needed so as not to affect flood level elevations at the U.S. Army Corps of Engineers flood protection projects located upstream in Williamson and Fairview, West Virginia. This conclusion was reached after twelve alternatives were hydraulically analyzed to test the effects of variations made to the bridge designs, pier alignments and configurations, raising the vertical alignment of the roadway above the flood levels as much as practical; relief structures, and channelization and floodplain modifications.

Select this Article		Control of Alluvial Fan Flooding: Reata Pass Channel, City of Scottsdale, Arizona Lan Weber, P.E., Ph.D., M.ASCE, Mark Landsiedel, P.E., and John Rodriguez, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)144 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract As part of the Desert Greenbelt Project, the Reata Pass Channel improvement is underway. This channel collects flows from the McDowell Mountain and is a naturally unconfined, unstable, alluvial fan. Unlike a typical fan, which has a single apex, this alluvial fan channel has multiple locations identified as major apexes, which results in an extensive flooding area as shown in the current Flood Insurance Rate Map. Without construction of a regional facility, current homes are subject to damages, and future developments will involve costly, uncoordinated local protection. In addition to flooding, the alluvial fan flow has extremely high erosion potential, which is destructive to land and structures and is unsafe for current and future residents. This paper describes the channel improvement plans, technical challenges, and the partnership between the approval agencies and the consultant team.

Select this Article		Channel Improvement Studies for Mission Creek, Santa Barbara R. Walton, P.E., A. Raman, J. Turpin, and V. Crisostomo, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)145 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An overflow analysis for major flood events was conducted on the Lower Mission Creek and Laguna Channel system in Santa Barbara, California. The study also considered two alternatives for channel improvements on the Lower Mission Creek. The link‐node hydrodynamic model, WDWBM, was set up for the study area and calibrated for the 50‐year flood event (January 10, 1995), and then various synthetic floods, representing the 25‐, 100‐ and 500‐year events, were simulated. The model was used to evaluate the reduction in overbank flooding, and subsequently the reduction in flood damage costs, for various potential system improvements. Alternatives evaluated included channel widening and reshaping, and replacing many of the existing bridges with larger structures. This study provided information to the LA District, Corps of Engineers for an economics impacts assessment of major floods.

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IRRIGATION PRACTICES

Select this Article		A Methodology for Assessing Success and Failure of an Agricultural Water Conservation Program Jobaid Kabir, M.ASCE and Quentin Martin, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)146 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Rice farming accounts for about 70 percent of all water diverted from the Lower Colorado River in Texas. Meeting irrigation water needs during droughts would be difficult in the future due to ever increasing demand for water for municipal and industrial use and consequently decreasing available supply for irrigation. To extend the available water supply from the lower Colorado River, the Lower Colorado River Authority (LCRA) launched its agricultural water conservation program in 1985 by developing an educational video informing rice farmers how to grow more rice with less water. In 1987 LCRA initiated the Irrigation Canal Rehabilitation Project for improving canal conveyance efficiency, reducing power consumption and improving canal system management. In 1989 LCRA started phased implementation of the Volumetric Pricing and Billing Project. These three initiatives were designed to conserve water in rice farming at the LCRA's Lakeside and Gulf Coast irrigation districts. Phased implementation of the Canal Rehabilitation and the Volumetric Pricing and Billing Projects were complete in 1996.

Select this Article		Evaluation of Agricultural Practices and Irrigation Scheduling on Water Resources, Southwestern Kansas Shimin Zou ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)147 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The effects of selected agricultural land‐management practices, major crops, and irrigation schedules on basinwide water resources are assessed using the SWAT model. Six different crops are simulated and different runoff curve numbers are utilized to represent different land‐management practices. Five different water stress factors are used to represent five irrigation scheduling scenarios. The simulation results show that both irrigation scheduling and conservation practices have significant effects on surface runoff and groundwater recharge. For a given conservation practice the mean annual surface runoff and groundwater recharge increase with the increase of irrigation frequency (less stressed conditions). For a given irrigation schedule (same stress factor) the mean annual groundwater recharge increases with the increase of efficiency of conservation practices. On the other hand, the mean annual surface runoff decreases with the increase of efficiency of conservation practices. However, the mean annual irrigation depth, evapotranspiration, and soil water content are relatively independent of the conservation practices and are dependent more on the irrigation schedules. Under the same conservation practice (SCS curve number = 60) and irrigation schedule (water stress factor (WSF) = 0.5), wheat produces the highest mean annual surface runoff and groundwater recharge along with the highest soil water content, the lowest irrigation requirement and the lowest evapotranspiration. Corn, on the other hand, has the lowest mean annual surface runoff, groundwater recharge, and soil water content, along with the highest irrigation requirement and the highest evapotranspiration.

Select this Article		Irrigation Water Management for Agricultural Development in Kuwait M. Abdal and M. Suleiman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)148 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water resources for agricultural development in Kuwait are very limited and the quality of the irrigation water is deteriorating from the continuous over pumping. Resources for irrigation water are limited to brackish underground water; treated sewage water; and expensive desalinated seawater. Water drainage is practically not common for agricultural development in Kuwait and salts accumulation is tremendously affected crops production. Evaporation is very high (3000mm/year) and rainfall is limited to 100mm/year. Soil water holding capacity is low (7%) and organic matter content is below 0.1%. Soil texture is mostly sandy with high calcareous materials and infiltration rate rage between 50‐100 cm/hour. Improvement of water irrigation in arid area of Kuwait requires intensive application of advance irrigation technology and train manpower to maintain irrigation equipment. Efficient water delivery to plant in the exact amount and time necessitate the understanding of the environmental condition in the arid area and various plant nutrients need. The high evaporation and water infiltration through the soil profile exert the introduction of soil conditioner and mulches to decrease water lose. Accumulation of salt materials within the soil profile from brackish water application affected crop production and plant growth. Introduction and installation of different drainage equipment and understanding salt leaching requirement will improve soil capability and increase crop yield. The paper discuss the environmental condition in arid area of Kuwait and the obstacles for crop production with emphasis on water irrigation management to improve crop production and efficient water application.

Select this Article		Water Requirement for Urban Landscape in Kuwait M. Abdal, M. Suleiman, and S. Al‐Ghaws ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)149 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Kuwait is a small country with enormous resource for human development and general industry. Urbanization within the country over the last forty years force the decision makers to beautified the cities and the neighborhood to enhance environmental condition. The main problem of urban landscape in Kuwait is the limitation of water resource and plants materials to tolerate the harsh arid environment. Water resources in Kuwait for urban landscape and greenery is limited to underground water, desalinated seawater, and treated sewage water. Underground water resources is limited with high salinity (3000‐10,000mg/l) and the quality is deteriorating from continuous over pumping. The desalinated seawater is too expensive for any agricultural activities, while the treated sewage water is most ideal resource for urban landscape and greenery for Kuwait. Soil of Kuwait is sandy in texture with small surface area and the soil water holding capacity is very small (7%). The evaporation is very high (3000 mm/year) and water infiltration through the soil profile is rapid (50‐100 cm/hour). Irrigation water management in arid environment of Kuwait requires the introduction of advance technology in equipment and manpower development to increase efficiency and save resource. The paper discusses the water resource in Kuwait for urban landscape and greenery with emphasis for irrigation management for efficient water application.

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RISK‐BASED REMEDIATION

Select this Article		Overview of the ASTM Risk‐Based Corrective Action (RBCA) Program John A. Connor, P.E. and Charles J. Newell, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)150 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Over the past five years risk‐based corrective action (RBCA) has become a more important approach for managing releases of chemicals to the environment. One of the key forces behind this transformation has been the efforts of American Society for Testing and Materials (ASTM) committee members who have developed standardized frameworks for implementing RBCA programs. Currently over 40 states are considering adoption of RBCA procedures for management of corrective action at USTs (Underground Storage Tanks) based on an ASTM (American Society of Testing and Materials) standard issued in 1995. A new ASTM Standard, Standard Provisional Guide to Risk‐Based Corrective Action” (PS 104‐98) was issued in 1998 and supercedes the older petroleum release standard. The new standard is more generic, and addresses a wide variety of chemical releases to the environment. Overall, the new focus on risk‐based approaches is a positive development. A risk‐based approach means environmental cleanups can be conducted on a rationale manner based on the actual risk that the site poses to society, and allows for a flexible approach to managing those risks. Movement towards risk‐based approaches does raise a concern that they will impose greater complexity on site evaluation processes, with significant variability among states. However, software tools can help to make make it easier to implement RBCA approaches at a wide variety of sites.

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SHARED USE OF TRANSBOUNDARY WATER RESOURCES

Select this Article		Rivers as Legal Structures Joseph W. Dellapenna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)151 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Fresh water is a uniquely important natural resource. Of all natural resources, only air is more ubiquitous, essential, or variable than water. Deprive us of air and we die in minutes. Deprive us of water and we die in days. Deprive us of food, and we can go on for weeks or months—as inmates of concentration camps or persons on hunger strikes have repeatedly demonstrated. And, as a Turkish businessman recently commented, “Countless millions of people have lived without love, but none without water.” Water is also our most nearly universal solvent. Almost anything will dissolve in water without affecting water's molecular structure, enabling us to make nearly infinitely diverse uses of water and to depend on its ability to recycle after almost any use. Water is found nearly everywhere on our planet in some form as it moves through the hydrologic cycle. While water is found nearly everywhere, water for our essential needs is often in the wrong place, or inadequate in amount, or too impure. Furthermore, precipitation patterns usually vary considerably with the season. The qualitative variability of water—one of the aspects of water that makes it so useful to us—means that pure water is a manufactured product that simply does not exist in nature. Humans and most plants and animals of use to humans can tolerate only a narrow range of impurities in the water they consume. Therefore, water's variability also makes usable forms of water a scarce and valuable commodity. Yet, there has been a nine‐fold increase in per capita consumption of water worldwide since 1900, arising from changing technologies and changing personal habits. Demand is further increased by burgeoning global population, at least in societies that fail to adjust their water consumption patterns to current realities. As a result, the management of fresh water generally requires the relocation of its flow in time or in space or both.

Select this Article		Draft Comprehensive Transboundary International Water Quality Management Agreement Conrad G. Keyes, Jr., F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)152 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The draft Comprehensive Transboundary International Water Quality Management (CTIWQM) draft agreement was first created in April of 1998. The process for the ASCE Border International Water Quality (BIWQ) Standards Committee was described at the ASCE Water Resources Planning and Management specialty conference in Chicago in June 1998. Revisions to the draft agreement have occurred between July 1998 and May 1999. The‐articles‐of‐the agreement include: (1) Declaration of policy and purposes, (2) General provisions, (3) Administration, (4) Transboundary water quality management, (5) Financing, (6) Dispute Resolution, (7) Effectuation, and (8) References. The purpose of the agreement is presented and the major articles of the agreement are summarized in this presentation. This comprehensive transboundary international water quality management agreement can be used by two adjoining countries, for a compact between states that are developing water quality management plans, and by Native Indian nations adjacent to large municipalities that require such agreements to satisfy source water protection on all fronts.

Select this Article		Transboundary Water Sharing: An International Issue of Significance Don Phelps, P.E., M.ASCE and Stephen Draper, Ph.D., P.E., Esq., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)153 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The need for effective international co‐operation among riparian countries is greater now than ever before. The demand for water in all countries is escalating and increasingly the harmful effects of activities in upstream countries are being observed. Over a third of the 200 international river basins are not covered by an international agreement; only some 30 have co‐operative institutional arrangements. Clearly, efforts are needed to formulate and reach agreement on an international “code of conduct” or convention in the utilization of shared water basins so that the water needs of some countries are not undermined by irresponsible utilization of water resources by others. Improved international co‐operation is also necessary regarding the transfer of knowledge and technology in the water resources field. The United Nations Convention on the Law of the Non‐Navigational Uses of International Watercourses, 1998, sets the standard for all agreements involving the shared use of transboundary water resources. It specifically establishes the dual criteria of “equitable and reasonable utilization” of the water resources and the need to “exchange data and consult on the possible effects of planned measures on the condition” of the water resource. The U.N. Convention provides the overall framework for transboundary water sharing. However, despite the presence of the Convention, specific agreements are necessary to implement effective water sharing. This paper provides a limited overview on the extent of the historical problems of transboundary water sharing, reviews the different mechanisms that have been adopted to resolve the problems, and introduces a series of model agreements that can be used to assist in resolving water sharing conflicts.

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WATERSHED MODELING

Select this Article		Integrating Geographic Information Systems (GIS) and Watershed Modeling David P. Preusch, P.E. and Massoud Rezakhani ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)154 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The integration of Geographic Information Systems (GIS) and watershed modeling is moving hydrologic and hydraulic analysis to a new dimension. What was once was a tedious process of defining drainage boundaries on topographic maps, planimetering drainage areas, area‐weighting runoff curve numbers from soils and land use maps, and inputting this information in a hydrologic model can now be automated using Digital Terrain Models (DTMs) and GIS technology. Digital data needed to perform this analysis are becoming more available from government agencies. Programs which link the digital watershed data to hydrologic models include WMS (Watershed Modeling System) from the Engineering Computer Graphics Lab at Brigham Young University and GISHYDRO2 from the University of Maryland. GIS is used to preprocess watershed data, watershed boundaries are delineated and drainage areas calculated from a DEM, Runoff Curve Numbers (RCNs) are generated, and runoff hydrographs are developed and displayed using graphical user interfaces.

Select this Article		A GIS Approach to Watershed Modeling in Maricopa County, Arizona E. James Nelson, Ph.D., M.ASCE, Christopher M. Smemoe, and Bing Zhao, Ph.D., P.E., A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)155 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Most conventional rainfall‐runoff modeling methods are tedious and time‐consuming. The Watershed Modeling System (WMS) is a comprehensive computer software application for watershed characterization and rainfall‐runoff modeling in a graphical user interface environment. Through several GIS operations and tight integration with GIS databases, WMS enables hydrologists and water resource engineers to perform rainfall‐runoff modeling more efficiently than conventional modeling methods. In this paper, methods of computing hydrologic parameters for the Flood Control District of Maricopa County are discussed, and demonstrated by applying them to the Gavilan Peak Watershed. This watershed is located in the vicinity of the community of New River in northern Maricopa County, Arizona.

Select this Article		Hydrologic Studies in Support of South Florida Ecosystem Restoration Raymond W. Schaffranek, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)156 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The U. S. Geological Survey (USGS), which is the principal science agency of the Department of the Interior, has a prominent role in the Federal Government's initiative aimed at restoration of the south Florida ecosystem. USGS scientists, in cooperation with researchers from other Federal and State agencies, as well as academia, are undertaking a comprehensive program to document the ecosystem's physical characteristics and properties in order to provide the basic data and scientific information needed to ensure its survivability. The objective is to invoke the latest scientific findings in the decision‐making process of land and resource managers for planning, evaluating, and executing restoration actions. One major component of the program is focused on investigating the hydrologic and hydraulic factors that affect the flow of water through the ecosystem. Hydrologic studies are yielding scientific findings that are helping to quantify hydroperiods and flow patterns that define wet‐season durations critical to sustaining habitat for flora and fauna. In addition, the results of these discrete process studies are serving to improve numerical models that are being used to investigate cause‐and‐effect relations among hydrologic processes. In this paper, several hydrologic studies that are being conducted in support of the development of a numerical model of the interface of the Everglades ecosystem with Florida Bay are described, some preliminary findings of these process studies are presented, and the role of these scientific findings in the development of models for the south Florida ecosystem is discussed.

Select this Article		Dynamic Evaluation of Frank Lake Management Alternatives Michael Bender, Mark Digel, and Alan Pentney ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)157 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A water balance analysis is presented for the Frank Lake wetland complex, located in southern Alberta, Canada. Frank Lake is operated by Ducks Unlimited to provide waterfowl and shorebird habitat, but also receives effluent from municipal and industrial sources. The complex represents an important staging area for spring and fall migration, and supports a seasonal resident population in the order of 10,000 ducks. The availability and reliability of the water supply, and potential improvement to the management of the wetland complex were evaluated for a number of management scenarios. The methodology for this assessment incorporated a dynamic modelling tool to conduct water balance simulations for a range of possible hydraulic configurations and operating policies for Frank Lake. The selected tool, STELLA by High Performance Systems Inc., facilitated efficient model calibration and testing of different management options. Experimental learning exercises were then used to evaluate alternative operating policies and diversion options based on several objectives. These objectives include flood control to prevent discharges to the Little Bow River, retention policies for efficient treatment of effluent prior to discharge from Frank Lake, and optimal control of water levels for shorebird habitat. The complexity of the water management objectives presented interesting challenges for selecting appropriate management measures. The dynamic object‐oriented water balance model proved to be a powerful analytical aid for improving the understanding of hydraulic characteristics of the wetland complex, for identifying practical operating rules for hydraulic control structures, and for altering the water management system of basin control structures and diversion channels. Additional studies for evaluating water quality are not reported here.

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BEST MANAGEMENT PRACTICES

Select this Article		Constructed Wetlands for Stormwater Management Marie L. O'Shea, Ph.D., Michael Borst, Daniel Liao, Ph.D., Shaw L. Yu, Ph.D., and T. Andrew Earles, M.S. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)158 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Wetland systems have long been used for treating municipal and industrial wastewater, and are often more cost‐effective than advanced wastewater‐treatment systems. The available literature on the performance of wastewater‐wetland systems is fairly extensive; however, information on the use of natural or constructed wetlands for controlling stormwater pollution, a newer application, is relatively scarce. In addition, the data available on wastewater wetlands may not apply directly to stormwater wetlands because of the unique characteristics of stormwater runoff, including: highly variable flow rates that are usually intermittent and seasonal; two‐to‐three order of magnitude between‐storm differences in the chemical and suspended solids composition of stormwater runoff; and, site‐specific nutrient ratios and concentrations. Consequently, in stormwater wetland systems, plant species' performance and removal efficiency is often tied to the biota's ability to tolerate these extremely variable conditions. Additional factors which effect pollutant removals include: the comparative contributions of settling, sorption, plant uptake under various hydrologic (e.g., detention time) conditions, and a pollutant's partitioning between the substratum, water column, and plant tissue. To address these unknowns and design concerns, a bench‐scale vegetative‐treatment‐cell study is being conducted for the purpose of examining nutrient and metal dynamics and removal efficiencies of three individual plant species under various stormwater pollutant loadings and detention times. The plant species being evaluated are: cattails (Typha latifolia), reeds (Phragmites sp.), and bulrushes (Scirpus sp.). For each of these species, two detention times (7 day and 14 day) and two pollutant loading levels (e.g., COD and SS >100 mg/l and <75 mg/l, respectively) are being investigated to determine wetland‐process dynamics; relative removal efficiencies of stormwater‐associated pollutants (e.g., total phosphorus and copper) as a function of detention time, water depths, and pollutant loadings, and expected solids removal and effluent‐particle‐size distributions.

Select this Article		Development of National Stormwater BMP Database Jane Clary, John O'Brien, and Ben Urbonas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)159 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Urban Water Resources Research Council of the American Society of Civil Engineers (ASCE) entered into a cooperative agreement with the U.S. Environmental Protection Agency (EPA) to develop a scientific approach and management tool for the information needed to evaluate the effectiveness of urban stormwater runoff BMPs nationwide. The long‐term goal of the project is to promote technical design improvements for BMPs and to better match their selection and design to the local stormwater problems being addressed. As a key component of this project, the ASCE project team has developed the National Stormwater BMP Database. The key features of this database are described in this paper The National Stormwater BMP Database is a user‐friendly, menu‐driven program developed in a run‐time version of Microsoft Access. The software has two key components: data entry and data retrieval. The data entry portion of the software serves multiple purposes including providing BMP researchers with a standard set of reporting parameters for BMP research and developing a more consistent and complete base of information for evaluating BMP performance and design. Key categories of data requested in the database include test site location characteristics, sponsoring and testing agencies, watershed characteristics, BMP design and cost data, monitoring locations and instrumentation, monitoring costs, precipitation data, flow data, and water quality data. All of the data are linked together based on key fields in multiple tables comprising the relational database. The data retrieval, or search engine, portion of the software enables users to retrieve BMP data sets based on a variety of search criteria such as geographic location, watershed size, BMP type, and water quality parameters. The user can either print search results or export the data to Microsoft Access or a comma‐delimited text file. As of early 1999, the database contains approximately 64 BMP studies which are being evaluated by the ASCE team to identify BMP performance measures and guide additional research activities.

Select this Article		Analysis of EPA's National Stormwater BMP Database Eric W. Strecker, Marcus M. Quigley, and Ben R. Urbonas ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)160 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This EPA cooperative research program with the American Society of Civil Engineers (ASCE) is charged with developing a more useful set of data on the performance and effectiveness of individual best management practices (BMPs) and to assess the relationship between measures of efficiency and BMP design. BMP monitoring data should not only be useful for a particular site, but also be useful for comparing studies of similar and different types of BMPs in other locations. Almost all past BMP monitoring studies have provided very limited data that is useful for comparing BMP design and selection. This paper overviews some of the comparability problems of past BMP monitoring. It suggests some of the ways that data should be collected to make it more useful for assessing factors (such as settling characteristics of inflow solids and physical features of the BMP) that might have led to the performance levels achieved. It recommends efficiency calculation methods and appropriate terminology to be used in evaluating BMP assessment studies. Finally, the paper also discusses other considerations that affect data transferability, such as the statistical tests used, reporting techniques, etc.

Select this Article		An Assessment of Urban Storm Water Quality Control in the Arid West: Best Management of Urban Storm Water or Urban Storm Water Polluters? Mark T. Murphy, Ph.D. and Burke Lokey, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)161 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Phase I of the EPA, National Storm Water Program has brought about a wide variety of outreach program, structures and ordinances to eliminate urban runoff pollution, collectively termed best management practices (BMPs). Success rate for these BMPs have varied widely, depending, in part, upon how storm water pollution is defined. In the arid West, receiving streams require different models than Eastern US rivers. Western watersheds differ fundamentally in storm duration/intensity, soil types, stream discharge, and background pollutant levels. We have developed a model that attempts to assess urban BMP efficiency on the total pollutant load using a simple spreadsheet and Monte‐Carlo style simulator. BMP efficiencies were taken from both literature reports and municipal records. The model suggests that many BMPs used to comply with the National Pollutant Discharge Elimination System requirements appear to have little impact on the annual load. It might be argued that many BMPs need to be evaluated at the source, not the receiving stream.

Select this Article		Are BMP Criteria Really Environmentally Friendly Larry A. Roesner, Ph.D., P.E. and Robert W. Brashear, Ph.D., P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)162 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Over the last eight to ten years, a number of Best Management Practices Manuals have been developed that address the control of urban runoff for receiving water quality protection. More recently, several papers that have investigated the effectiveness of these BMPs in protecting the environment and have concluded that they do not. Investigation of both the design practices and the effectiveness investigations reveals that there is a lot of ignorance in the scientific community about what constitutes a properly designed BMP and what it really achieves, with respect to environmental protection. Another issue that confuses the urban drainage community is defining what constitutes an socially acceptable urban stream. This paper discusses the state‐of‐the‐art in BMP design practice and points out its strengths and weaknesses with respect to real protection of the downstream receiving water environment. The paper recommends a design criteria development approach that can be applied over a wide variety of climatologic, topologic, and geologic conditions to protect receiving waters systems.

Select this Article		Robust On ‐ Line Monitoring of Mixing Quality in Water Supply Networks Mietek A. Brdys and Zbigniew Lisiak ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)163 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The paper applies an algorithm for recursive estimation of variables and parameters in general dynamic networks that has been developed by to robust on‐line monitoring of the mixing water quality in dynamic water networks. A complete hydraulic information is assumed to be available on‐line. First a parsimonious parametrisation of a mathematical model of mixing quality is derived. Next a recursive estimation algorithm is designed that uses the model and available measurements to generate on‐line robust estimates of unknown quantities. The parameters and variables are estimated simultaneously. Robustness of the estimates is achieved through non‐probabilistic set‐bounded modelling of uncertainty in the measurement and modelling errors. The stable and tight bounds on the estimated quantities are obtained by employing a concept of moving information window. The estimation scheme is very flexible in integrating the information available. In particular, if only concentrations of the quality parameters in a network inputs are measured, the estimator operates as the quality simulator under uncertain models and not accurately known inputs. This can be viewed as a sort of generic soft sensor. Performance of the monitoring scheme is illustrated by applications to two case‐study networks.

Select this Article		Bioretention: Water Quality Performance Data and Design Modifications Derek A. Winogradoff and Lany S. Coffman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)164 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Prince George's County, Maryland first introduced the bioretention device (commonly referred to as a “rain garden”) in 1990. Since that time, they have been in widespread use across the Country to provide an economical means of efficiently treating stormwater runoff. Utilizing physical, chemical and biological treatment processes within an aerobic soil media / vegetated filter system, bioretention has been shown to be highly effective in removing pollutants such as heavy metals and nutrients from urban runoff. By capturing, infiltrating or filtering stormwater runoff close to the source, the use of bioretention treatment can also restore hydrologic functions. Reproducing the predevelopment hydrologic regimes of a site is one of the most important factors in maintaining recharge areas, protecting the ecological and physical integrity receiving waters, small streams and wetlands. This paper summarizes the most recent laboratory and field studies and provides suggestions on design modifications to increase the effectiveness of bioretention.

Select this Article		Stormwater Wetland BMP Performance — A Continuing Study Robert G. Traver, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)165 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The author presents results from two of his graduate students from an ongoing research project into the effectiveness of a stormwater wetland Best Management Practice. The first thesis examines the calibration and performance of a hydrologic model in recreating recorded storm events from both the stormwater wetlands and the wetlands stream, while the second examines the nutrient removal effectiveness of the stormwater wetland basin.

Select this Article		Integrating Urban Design for Creek Restoration Projects Bruce M. Phillips, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)166 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Creek restoration in highly urbanized settings offer unique opportunities to enrich the community in decaying brownfield areas. These projects can enhance a sense of identity through the creation of a cultural system which results in a landmark focal point, illustrating that flood control does not have to be ugly. Historically successful urban creek restoration projects which have integrated urban design elements have resulted in “river walk” type features which can enhance the quality of life and human activity, as well as environmental enhancement. Urban redevelopment projects often include existing flood control facilities or flood protection requirements which typically manifest as physical constraints rather than approached as opportunities. Introduction of the urban design element as part of the flood control planning assists in developing a vision for the project which integrates the adjacent redevelopment areas that will result in bringing vitality and grace to the community. Creek restoration through urban centers requires a flexible design program resulting from a collaboration of river engineering, hydraulics, urban design, environmental and ecology, landscape and bioengineering, and business development which allows collective solutions. Urban design allows water to serve as a common thread that links the project's spaces together. Important issues which need to be addressed in the planning process includes (1) transportation, (2) landscape restoration, (3) ecosystem benefits, (4) historical landscape and native feature preservation, and (5) recreational design elements. The driving concern in the majority of urban redevelopment projects is restoring the economic growth and vitality of the community. The “river walk” feature provides a vehicle to attract the general public to this area and ensure the economic success of the project. A case study is reviewed which applied urban design planning for a commercial redevelopment project in the City of Vista, California involving the replacement of a 1950 concrete flood control channel into a restored natural “river walk” linear park. The proposed creek restoration would provide the focal point for an economic revitalization of the downtown area that includes restaurants, shops, and entertainment center, with the creek providing the common linkage.

Select this Article		Field Test of Grassed Swale Performance in Removing Runoff Pollution Jan‐Tai Kuo, Shaw L. Yu, M.ASCE, Elizabeth A. Fassman, and Henry Pan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)167 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The following paper presents results of field tests of pollutant removal efficiencies of grassed swales conducted in Taiwan and Virginia. Swales are a low cost stormwater best management practice (BMP), which have been reported as a cost‐effective method for controlling runoff pollution from land surfaces, especially highways and agricultural lands. The Virginia experiments tested a highway median swale, while the Taiwan experiments were conducted on an agricultural test farm. Average pollutant removal efficiencies reported for the test swales vary from 14% to 99% for total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP). The wide range of performance results indicates the importance of design parameters such as length, longitudinal slope, and the presence of check dams. Minimum design guidelines for use of swales as BMPs are suggested.

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REGIONAL WATER RESOURCES MANAGEMENT IN SOUTHEAST ASIA

Select this Article		Small Scale Irrigation Weirs in Laos: Post‐Construction System Performance Max McGowan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)168 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Between 1978 and 1994, Quaker Service Laos (QSL), a private non‐governmental relief and development agency, provided grant funding assistance for over 70 small scale irrigation projects in Laos. Total QSL program assistance was slightly over $1,200,000 as of July, 1994. In 1994 QSL conducted a project monitoring survey of 60 QSL‐assisted small scale irrigation projects throughout Laos. The survey collected information from farmers using the systems, regarding the operational status of the projects and the effect of the projects on increases in area under cultivation and rice production. A brief background and description of the Quaker Service Laos small scale irrigation program and an overview of the survey is provided. Small in‐stream diversion weir projects are given a more in‐depth study, including an analysis of the value of the increased rice production. Direct project costs are also calculated, and certain relationships between costs and benefits are explored. All of the results are based on farmer's responses, and are considered indicative, not definitive.

Select this Article		Area‐Wide Environmental Assessment in Dong Nai Province, Vietnam Harold Jack Day, P.E., M.ASCE, Walter M. Grayman, P.E., M.ASCE, and Pham Gia Hai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)169 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A two‐year study on industrial pollution reduction in Dong Nai Province of Vietnam was conducted. The project was a cooperative effort between the United Nations (UNDP and UNIDO) and the Federal and Provincial governments in Vietnam. A comprehensive approach was used to assess the impacts and strategies for reducing industrial, municipal and agricultural pollution to the water, air and land. The strategy is based upon use of knowledge in four subject areas, economics, ecology, technology and institutions, integrated within a framework for regional environmental quality management, sometimes called Areawide Environmental Quality Management (AEQM). Environmental modeling and monitoring provided basic data and information on the likely impacts of alternative management strategies.

Select this Article		System Analysis for Water Resources Management in Kao‐Ping River Basin, Taiwan S. K. Ning, H. W. Chen, and Ni‐Bin Chang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)170 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The conservation of water resources in the river basin depends critically on the internal features of availability of water resources over seasons and its transfer requirements over natural boundary. The inherent needs and limitations of water resources redistribution and transfer between or within river basin systems have become one of the most stringent challenges in south Taiwan. However, due to the remarkable differences of rainfall between dry and wet seasons in Kao‐Ping river basins, the water resources management strategies have to be reconsidered based on the significant changes of stream flows within the water year. This paper explores the impacts of water resources redistribution and pollution prevention actions in Kao‐Ping river system in order to ensure the essential water quality of water body in the future. Focus will be placed on the conjunctive use of water resources within Kao‐Ping and Tseng‐Wen river basin systems and its subsequent impact to the water quality in Kao‐Ping river system. It shows such transfer requirements and pollution prevention actions cannot improve water quality in the Kao‐Ping river basin especially in the dry season. Further pollution control actions arc needed in the future.

Select this Article		Integrated Water Quality Management in the Tha Chin River Basin, Thailand: Using the Linkage of a Simulation Model and a Desktop GIS Wijarn Simachaya and Isobel Heathcote ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)171 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Tha Chin River Basin is the second most important basin in Thailand, covering 12,000 km² and a population of 1.2 million. The main stem of the river is about 320 km in length, and over much of that distance water quality has deteriorated significantly over the past two decades, largely as a result of waste inputs from municipal sewage, agricultural activities, and industrial operations. Although the Thai government has launched many projects to resolve these problems, few of these attempted to take a basin‐wide approach. Most actions to date have been local in nature, with the result that water quality continues to deteriorate in the river. Currently, the most urgent water quality problems relate to dissolved oxygen depletion and high loadings of ammonia, primarily from agricultural sources. The research described in this paper is the first effort to develop a basin‐wide management plan for the Tha Chin River Basin. It brings together US EPA's WASP5 (Water Analysis Simulation Program) model and ArcView, a desktop Geographic Information System. The linkage between the two systems was created using the object‐oriented language AVENUE. The linked model was then used to simulate water quality in the river, as a method of testing a variety of management scenarios under present and future conditions. Significant analytical challenges in this work related to the cultural and economic context in Thailand. GIS data, although available, were inadequately digitized and required extensive manipulation. Available water quality data were limited and largely inadequate to characterize tidal reaches of the river. Finally, the economic crisis in the country imposed a variety of constraints on data acquisition and made prioritization of remedial measures a central requirement. The resolution of these research obstacles may be of special interest to those working with agencies and issues in other less developed countries.

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PRECIPITATION & PEAK FLOW ESTIMATION FOR FLOODS

Select this Article		Site Specific PMP and Inflow Design Flood for Lynx Lake Dam, Near Prescott Arizona George V. Sabol, PhD, P.E., F.ASCE and John F. Henz, CCM ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)172 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Lynx Lake Dam is on Lynx Creek in Yavapai County, near Prescott, Arizona. The dam is owned and operated by the Arizona Game and Fish Department for wildlife and recreational purposes. The dam and lake are contained within the Prescott National Forest and therefore within the resource management of the U.S. Forest Service. As part of the National Dam Safety Inspection Program, the dam was determined to be inadequate to safely pass the spillway inflow design flood without overtopping the earthen and rock embankment. The dam is under the jurisdiction of the Arizona Department of Water Resources which classified the dam as unsafe, non‐emergency. Accordingly, the Arizona Game and Fish Department was required to bring the dam into compliance with Arizona rules and regulations for jurisdictional dams. The initial hydrologic studies, using traditional methods for estimating the probable maximum precipitation (PMP) and the probable maximum flood (PMF) indicated that the spillway could only pass about 20 percent of the regulatory inflow design flood (0.5 PMF). However, spillway enlargement and/or dam raising require review and approval by the U.S. Forest Service along with environmental compliance. Additionally, the cost of such spillway enlargement and dam modifications could be significant. Therefore, due to regulatory, environmental and economic factors, there was interest by the Arizona Game and Fish Department in cooperation with the U.S. Forest Service and the Arizona Department of Water Resources to enter into a reappraisal of the inflow design flood and assessment of dam modifications.

Select this Article		Design Rainfall Criteria for Maricopa County, Arizona George V. Sabol, PhD, P.E., F.ASCE and Amir M. Motamedi, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)173 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Maricopa County, in Central Arizona, comprises a large and diverse land area and includes the Phoenix metropolitan area. A comprehensive drainage design procedure is used for purposes of flood control, urban development, transportation design and other water resources and land development purposes. In 1990 the Flood Control District of Maricopa County developed a drainage design manual for hydrology. As part of that manual, a design rainfall criteria was developed for severe, local storms. Such storms, often called thunderstorms, are the flood producing rainfalls for relatively small, typically less than 50 square miles, watersheds in Maricopa County. Research in such severe, local storms resulted in the development of design rainfall criteria to be used for drainage design in Maricopa County. The Maricopa County local storm design rainfall criteria are based on records of historic, regional rainfalls. The local storm rainfall criteria define the temporal and spatial distributions of such severe thunderstorms. The area averaged temporal distribution of the storm is determined to vary according to the size of the storm, and therefore, in application, varies according to the size of the drainage area. Both the equivalent uniform depth of rainfall and also the areal averaged rainfall intensity over the entire watershed diminishes with increasingly larger watershed area. The design storm is defined by a series of temporal distributions, called storm patterns, that are selected according to drainage area. A rainfall depth‐area reduction factor is also provided. The drainage design procedure in Maricopa County is developed for use with the HEC‐1 rainfall‐runoff computer program. The use of the Maricopa County design rainfall criteria with the HEC‐1 program is facilitated by a separate HEC‐1 input file‐processing program that was prepared by the Flood Control District. The historic rainfall records and development of the design rainfall criteria are presented. That criteria, along with the overall drainage design procedure, have produced consistent and reasonable estimates of flood magnitudes for use in Maricopa County.

Select this Article		Frequency of Heavy Rainfall in Southeastern Wisconsin Eric D. Loucks and Amy L. Sansone ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)174 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Rainfall frequency data is an important issue in Greater Milwaukee. The Milwaukee area is traversed by four large rivers and dozens of tributaries. In the 1997 and 1998 events, the heavy rainfalls caused widespread flooding due to both failure of local drainage systems and overbank flooding from the rivers and streams. As the area, particularly Milwaukee County, seeks solutions to these flooding problems, reliable rainfall frequency estimates will be critical to the development of policies and structural solutions to address these flooding problems. At least three comprehensive rainfall frequency studies for the Milwaukee area have been undertaken in the last 40 years. Although each study used a different period of record, they all based their results on fits to the Extreme Value Type I or Gumbel distribution. The 100‐year, 24‐hour rainfall estimates from these studies are nearly identical ranging from 13.6 to 14.1 cm. However, based on recent experience and careful reexamination of the historical records, it appears these studies have greatly underestimated the actual 100‐year, 24‐hour rainfall volume.

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GROUNDWATER RECHARGE

Select this Article		Middle New River Watercourse Master Plan — Groundwater Recharge Stephanie Gerlach, A.M.ASCE, Scot. S. Schlund, P.E., and Herman Bouwer, PhD, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)175 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Flood Control District of Maricopa County (District), in cooperation with the City of Peoria (Peoria) and the City of Glendale (Glendale), is currently performing a master plan study of New River from the confluence of Skunk Creek to the New River Dam. Groundwater recharge is included in the study in accordance with requirement of Arizona statutes for such watercourse master plans. Research is being conducted to determine the feasibility of groundwater recharge in that reach of New River. The study considers several elements: recharge objectives, water supply, hydrogeology, and recharge technology. The main objective of the recharge project is to enhance the water supplies of the Cities of Peoria and Glendale. Other objectives being explored include storage of wastewater treatment plant reuse water and Colorado River water, and recreational, wildlife and aesthetic benefits. The project could potentially use water from either storm water runoff, wastewater treatment plant reuse water or the Central Arizona Project (CAP) water. The study considers the amount attainable from each source in terms of average flow, peak flow, and variability. The study will also consider water quality and variability of water quality. The water for recharge must not cause or contribute to the violation of aquifer water quality standards. Also, the water will be studied for potential plugging by suspended solids, geochemical reactions and biological growth.

Select this Article		Optimal Operation of Soil Aquifer Treatment Systems under Uncertainty Using Genetic Algorithms Aihua Tang, Ph.D., A.M.ASCE and Larry W. Mays, Ph.D., P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)176 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A stochastic optimization model with chance‐constraints has been developed to account for parameter uncertainty and an enhanced genetic algorithm is applied to solve the optimal operation problem of the SAT systems. The model identifies the optimal operation schedules, i.e., the water application time and drying time for the infiltration basins to obtain a maximum hydraulic loading rate. Hydraulic criteria are satisfied using bound constraints on the water content. There are incorporated chance constraints to account for the uncertainty due to physical variability and parameter measurement.

Select this Article		Using Simulation to Develop a Conjunctive Use Policy: The Salt River Project Experience Yvonne Reining, M.ASCE, Jon Behrens, and Charles Ester ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)177 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Salt River Project (SRP) is one of the oldest reclamation projects in the United States. With its formation in 1903, SRP's purpose was to manage and deliver surface and groundwater to agricultural users within its 250,000 acres (101,172 hectares) service area. The water demand from this service area is satisfied with surface water stored in six reservoirs and groundwater is pumped from about 250 wells. Surface water and groundwater are managed conjunctively. Prior to safety‐of‐dams modifications, SRP's reservoir system was designed strictly for water conservation. A 77‐ft (23.5m) addition to Roosevelt Dam provides for some additional conservation space and the creation of a flood‐control and safety‐of‐dams pool. SRP continues to be the operator of the dam and reservoir, but has now also flood‐control responsibility. Operating the SRP system is challenging because the storage on the Verde is much smaller than on the Salt and there is no flood‐control space on the Verde system. This means that the Verde River system is much more likely to spill and cause downstream flooding than is the Salt system. SRP is charged with managing these two rivers and the groundwater to maximize water conservation. Creation of Groundwater Saving Facility legislation also has forced SRP to change its conjunctive use operating philosophy. In addition, other parties have vested rights to some portions of the water storage in both the Salt and Verde reservoirs. SRP must, by existing operating agreements, manage the modified reservoir system in such a way as not to impact prior water rights interests. SRP is using the RiverSim basin modeling kit to simulate these conflicting interests and come up with a new reservoir operating philosophy.

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TRENDS IN U.S.‐MEXICO WATER RESOURCES MANAGEMENT

Select this Article		Technical Assistance and the Project Development Assistance Program: Border Environment Cooperation Commission Juan Rangel and Bernardino Olague, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)178 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The governments of the United States and Mexico recognized the severity of the environmental infrastructure along the U.S. – Mexico border. Thus, creating the Border Environment Cooperation Commission (BECC) as a side agreements to the North American Free Trade Agreement. The North American Development Bank (NADB), sister organization of the BECC, was also created under this agreement in 1993.One of the BECC's functions is to assist communities develop infrastructure projects and project proposals for BECC certification. To execute this function, the BECC created a Technical Assistance Program that has two mechanisms through which grants can be awarded to communities for the development of projects and preparation of various studies. These mechanisms include the Project Development Assistance Program (PDAP) which operates with grants contributed by the Environmental Protection Agency (EPA). To date, the BECC has made contributions in the order of $568 million, through its operating technical assistance funds and the PDAP.

Select this Article		Accessing Information on U.S.‐Mexico Water Resources Management Opportunities Mark W. Kiligore, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)179 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The North American Free Trade Agreement (NAFTA) was signed in 1993 and implemented in 1994. Five years have now passed, and some progress has been made in addressing U.S.‐Mexico border water quality problems. The promise of a leveraged multi‐billion dollar improvement program has yet to materialize. Human health issues, water pollution, water quantity shortages and too much demand on limited water and wastewater infrastructure all contribute to continuing environmental difficulties in the border region. This paper will focus on: Actions by the Border Environment Cooperation Commission (BECC) to date; North American Development Bank's performance in finding projects; EPA's Border 21 Program; and useful resources for engineers.

Select this Article		National Weather Service River and Flood Forecasting Technology Transfer Project for Mexico Curtis B. Barrett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)180 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In 1996, the United States and Mexico began to cooperate on transferring operational National Weather Service (NWS) River Forecast System (NWSRFS) technology to the Comisión Nacional del Agua (CNA). As a result, a cost reimbursable river‐forecasting technology transfer project is being undertaken as part of a multi year, comprehensive, water‐management modernization program, known as PROMMA (Programa de Modernización del Manejo del Agua). This modernization program is being undertaken by CNA with Mexican government and World Bank funding. PROMMA is a large, multi facet project designed to decentralize water management in Mexico and provide integrated regional water‐resources management. Project areas concern surface water, groundwater, water quality, dam safety, data communications, and infrastructure.

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DROUGHT PLANNING & MODELING

Select this Article		Options for Water Conservation in Casablanca, Morocco Mohamed Lahlou and Dale Colyer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)181 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Conservation programs in Morocco have been implemented only occasionally, usually during a water shortage crisis arising either from technical reasons or from drought. In the past increases in demand have been met by development of supplies, but these sources are limited. Some of the conservation approaches used in this study included public education, plumbing code revisions to require use of water conservation devises, leak detection and repair, pricing policy, metering, and pressure reduction. The results indicate that considerable saving in water use can be attained through a comprehensive water demand management program.

Select this Article		Derivation of Water Rationing Rules Using Goal Programming Peiffer A. Brandt and Donald T. Lauria ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)182 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract When the reservoir capacity of a municipality is insufficient for water demands to be met, the typical response of utilities is to invoke rationing. The amount of water in storage is the criterion most frequently used for rationing. If storage is above the trigger level, rationing is not required. In some cases, different storage levels trigger different stages or types of rationing; e.g. voluntary restrictions of, say, lawn irrigation may be requested when the level is relatively high, and mandatory rationing may be required when it is low. Setting trigger levels in the rationing rule is usually a matter of judgment. Rationing rules do not always work well. They may require too much or too little rationing, sometimes too soon or too late. The problem in selecting rules is particularly difficult for 1) water systems that are just approaching the limits of their capacity, 2) unusually dry years, and 3) utilities that lack extensive experience in operating their systems. The economic consequences of rationing can be severe. For example, restrictions on outdoor watering can result in expensive landscape losses for households and lost revenue for utilities; hence, mistakes in setting rationing policy need to be minimized. This research aims at developing an improved methodology for rationing, one less dependent on experience and judgment and more reliant on mathematical optimization and statistical analysis.

Select this Article		Dynamic Modeling of Droughts Vinod K. Lohani, A.M.ASCE and G. V. Loganathan, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)183 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Long term monthly records of Palmer drought index in respect of one climatic division each in Arizona, California, and Virginia are analyzed to explain empirically observed bi‐modal distribution. The classical Fokker Planck equation is solved to obtain steady state and time varying probability density functions of the index. An example is presented showing application of computed densities in making forecasts of index values.

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WATER RIGHTS MARKETS WATER LAW SESSION

Select this Article		Is Privatization Practical When Water is the Paradigm Public Property? Joseph W. Dellapenna ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)184 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Privatization is a fashionable idea for water resources. Its champions advance private property and markets as nearly painless means for resolving problems of water allocation, distribution, and preservation. The foremost champions of private property in, and markets for, water mostly are professional economists, which is only to be expected as the study and employment of markets is, at least in western economics, their stock in trade. They advocate privatization for national or local managerial processes. The champions of markets present markets as functioning automatically and nearly painlessly and in our society market‐based allocations have always been accorded a very strong presumption of validity. The presumption of validity has only reinforced by the utter failure of socialism.

Select this Article		Tradeable Water Withdrawal Permits for Traditionally Riparian Areas J. Wayland Eheart and Jessica J. Cragan ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)185 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In a previous paper by the same authors, several methods of defining and allocating water withdrawal permits were compared. On the basis of a modeling study for a small unimpounded Midwestern basin, it was found that water withdrawal permits that were defined to leave a fraction of the streamflowin the stream were very effective, when that fraction was appropriately chosen, at both maintaining minimum streamflows and upholding profits from irrigated agriculture. In the present paper, we address the issues surrounding the consolidation of withdrawal permits through markets. In particular, we determine how the low flow reliability and users' profits are affected by this regulatory feature. The paper uses the same modeling method and example application as the previous paper, which focuses on irrigated agriculture as the water consuming and profit making economic activity. We envision the existence of a regulatory authority which has already determined how to allocate water to a particular group of riparian surface water users, and which is now considering whether and how to allow those users to trade permits. It wishes to know how such permit trading would affect the frequency of low streamflow incidents and users' profits.

Select this Article		The Elements and Structure of a “Full Service” Water Market Daniel Sheer, Debra Knopman, David Eaton, and Theodore Rosenberg ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)186 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract There is a long history of water transfers in the West. These are largely “simple” transfers, with little or no change in the place, timing, and purpose of use. As a result, they have few effects on those not involved in the trade (externalities), and provide only modest gains in the economic efficiency of water use. Pressure is growing to consider “complex” water transfers, which do involve changes in time, place, and type of use. These usually involve quite significant externalities, and the potential for enormous economic gains as well. In this paper we propose a structure for a formal, full service water market which can minimize the difficulties and reduce the transaction costs associated with complex transfers, by explicitly incorporating protection of third party and environmental interests in the trading process. We believe that this will allow a formal market to improve economic efficiency. The structure we describe is general, and is intended to be customized to fit the needs of the particular geographic location of a particular market. The need to specify geographic extent is dealt with in detail in the paper. While the structure may be adaptable to interstate transfers, we will not deal with interstate issues in this paper. The political, legal, and constitutional issues involved in interstate transfers are beyond the scope of this effort.

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COMPUTER‐BASED TOOLS FOR INTERACTIVE DECISION SUPPORT IN WATER & ENVIRONMENTAL SYSTEMS

Select this Article		STREMTUL 2.0 — A Visual Method to Manipulate and Display TR‐20 Keith L. Harner, P.E., M.ASCE and Andrew C. Weaver, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)187 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Stremtul is a computer program which allows the user to modify and build TR‐20 input files visually. The program also allows the user to visually display differences in the existing and future storm water flow rates based upon different development patterns or storm water control measures. This manuscript provides the technical information on how the computer program accomplishes the visual interface with TR‐20.

Select this Article		A Spatial Hydrology Model for Flood Estimation M. Hubail Ajward and I. Muzik ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)188 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Traditional methods for flood hydrograph estimation involves the use of observed rainfall runoff data and unit hydrographs derived from them. In the recent past, the use of physically based rainfall runoff estimation methods such as the geomorphologic instantaneous unit hydrograph (GIUH) have evolved. This paper presents a physically based flood hydrograph simulation model, formulated on the concept of a spatially derived unit hydrograph. The theoretical basis of the model, is the time‐area method for unit hydrograph derivation. By using the geographic information system (GIS), the model is able to account for spatially varied data of soils and land use/land cover. The model employs a cell structure and routes the spatially distributed excess rainfall from one cell to the other following the direction of steepest descent over the landscape to the watershed outlet. Application of the model is illustrated by an example using data from a 230 km² watershed located on the eastern slopes of the Canadian Rockies in Alberta, Canada. The derived spatial unit hydrographs gave excellent results in simulating the observed flood hydrographs.

Select this Article		The Internet: Water Resources Project Management for the Next Millennium — Today Marc P. Walch, P.E. and Jonathan N. Antevy ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)189 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water Resources Project Management in the next millennium will involve Information Management of a digital environment. The Internet offers us a media with literally infinite possibilities to manage projects.

Select this Article		Use of Object‐Oriented Programming in Water Supply System Modeling Wendy J. Cox Royston ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)190 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Object‐oriented programming can be an effective tool in watershed management. It allows the modeler to create model structures that are easily understood. As a result, interested parties can make better informed decisions without having to decipher complex model code, increasing opportunities for stakeholder involvement in the modeling process. STELLA® is one example of an object‐oriented programming language. Two examples of reservoir operations models developed using STELLA® are presented. The first model was used to evaluate the effects of various withdrawal and release scenarios on the safe yield of a proposed water supply reservoir. The existing system, which consists of five reservoirs, was simulated as a single large reservoir connected to the proposed reservoir. The model predicted the system's safe yield under a variety of operating conditions and determined which factors had the greatest impact on the safe yield. The second model, which simulated the upper Black Warrior River Basin in Alabama, was developed in part to determine whether additional system storage was required to accommodate multiple uses including power generation, navigation, flood control, and drinking water supply. The model was set up so that it could be run under conditions similar to those of an existing HEC‐5 model of the system to facilitate comparisons of the two models' predictions. Although results from the two models were similar, the STELLA® model was easily understood and used by individuals not involved in the model development process. It was also more easily modified to simulate alternate operating procedures. Under HEC‐5 model conditions, the model showed that additional storage was required to prevent shortages. However, under alternate operating conditions, the model predicted that existing system storage could be adequate. These two models demonstrate the potential for using object‐oriented programming to develop watershed management models that are easily comprehended and utilized by everyone involved.

Select this Article		Hydrology, Power Studies, Hydraulics, and Fish Habitat: IMP 4.0 — Software for Teaching Charles D. D. Howard and Tracey Kenward ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)191 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Integrated Method for Power (IMP) was developed to assist in the assessment of economic potential and instream environmental impacts of small hydro sites on ungaged watersheds. The objective of the software is to reduce the investment risks, especially in remote areas where data are sparse, by raising the level of technology used in studies. IMP 4.0 is suitable for teaching and training because it deals with common issues in water resources engineering. IMP 4.0 combines theoretical and practical concepts, it provides real data, and has a convenient graphical interface.

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ECONOMICS & THE COLORADO RIVER

Select this Article		Benefit and Cost Analysis: Western Threatened & Endangered Fish Critical Habitat Earl R. Ekstrand and John Loomis ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)192 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A current project has estimated national economic benefits for preserving threatened and endangered (T&E) fish species on the Colorado Plateau in the Four Corners Region of the U.S. These species are affected by Bureau of Reclamation (BOR) activities and BOR has ongoing projects to preserve these species. Also, U.S. Fish and Wildlife Service has designated critical habitat for them. Values for U.S. households were estimated by incorporating respondent uncertainty into the model. However, in the past, little effort has been made to compare these benefits with the costs that are incurred to protect the species and habitat. It is assumed by researchers and society that the benefits will exceed costs but no effort is made to test this assumption. This research examines the national costs along with the regional costs for preserving these species and habitat and compare those costs to the benefits to determine the benefit/cost ratio.

Select this Article		Economic Impact of Changes in Water Supply Salinity Ray Mokhtari, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)193 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Salinity refers to the total dissolved solids (TDS) content of water and is of concern because high TDS water can cause corrosion of pipes, scaling, and spotting; reduce the useful life of water‐using appliances; and require greater use of cleaning products. Vegetation can experience restricted growth when salinity becomes too high. As salinity increases, industrial users incur extra treatment costs for water uses in cooling towers, boilers and manufacturing processes. At sufficiently high levels, salty water also begins to have an unpleasant taste, resulting in increased purchases of bottled water or home treatment devices. High salinity is a primary water quality constraint to water recycling and groundwater replenishment activities.

Select this Article		Economic Benefits of Recharging Aquifers with Colorado River Water Ed Harvey, Steve Robbins, P.E., and Doug Jeavons ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)194 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Groundwater recharge has become an increasingly popular method of enhancing water supplies for the Western U.S. over the past 15 years. The Las Vegas Valley Water District and the City of Las Vegas recharge treated Colorado River water for peak summer usage. Arizona providers make extensive use of groundwater recharge of Colorado River water, typically conveyed by the Central Arizona Project Canal. For California, Nevada, and other states, recharge efforts and plans are proliferating. Colorado River water serves a unique role within the resource portfolios of Basin water providers. If the provider has access to a portion of its State's allocation, the quantity of water can be ample. Basin water providers also recognize that previously allocated Colorado River waters not applied to beneficial use can be lost to others. In its raw form at the point of diversion, this water source is very inexpensive in relative terms. However, conveyance and water treatment can add considerably to the expense of Colorado River water supplies for certain users.

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EPA URBAN WATERSHEDS MANAGEMENT BRANCH: WET WEATHER FLOW RESEARCH

Select this Article		Street Surface Storage for CSO Control Stuart Walesh, P.E., M.ASCE, Carolyn Esposito, and Robert Carr, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)195 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a discussion of the use of on‐street storage as an effective means to control stormwater runoff. It focuses on the success achieved by using street storage in two communities in Illinois and includes a description and evaluation of how this technology eliminated surcharging and basement flooding, complied with regulations and proved to be a cost‐effective solution which earned public support. Wet weather flow (WWF), including combine sewer overflow (CSO) and stormwater discharges, is one of the leading causes of water‐quality impairment in the United States today. Improvement of controls is one of two priority water focus areas cited by the EPA's Office of Water in its National Agenda for the Future. Pollution problems stemming from WWF are extensive throughout the country. Many CSO occurrences can be eliminated, or their impacts attenuated by flow retardation techniques. However, even as these retardation techniques may attenuate the CSO, they usually exacerbate other problems, e.g., basement flooding. In addition, CSOs provide relief only for sewer systems; upstream areas may not have overflow routing and thus, the system is relieved by surcharging into basements, or to the ground surfaces. Surcharging and flooding cause health hazards, structural damage (due to hydrostatic pressures and/or washouts) and damage to personal property. Over the past several years, numerous investigations have been undertaken to determine cost‐effective methods of abating CSO. Much of this effort has concentrated on methods of controlling and retaining upstream stormwater. One such cost‐effective method is source control. This approach avoids upstream flooding by not allowing stormwater into sewers until capacity is available, and avoids downstream surcharging and CSO by permitting downstream flow to be conveyed away before upstream flows can arrive. Source control temporarily stores stormwater in urban areas on the surface (on‐street and off‐street) and, as needed, below the surface, close to the source. “Close to the source” refers to the stormwater prior to its entry to a combined sewer or storm sewer. This on‐ and off‐street storage may be an effective means to control stormwater runoff, protecting intercepting sewers from surcharging and/or creating CSO conditions.

Select this Article		Environmental Technology Verification (ETV) Program: Wet‐Weather Flow/Source Water Protection Mary K. Stinson, Anthony N. Tafuri, P.E., and Raymond M. Frederick ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)196 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an overview of the Environmental Protection Agency's (EPA) Environmental Technology Verification (ETV) program which was established to overcome the numerous impediments to commercialization experienced by developers of innovative environmental technologies. Among those most frequently mentioned is the lack of credible performance data. It is believed that objective, independently acquired, high quality performance data and operational information on new technologies will significantly facilitate the use, permitting, financing, export, purchase, and general marketplace acceptance of such technologies. The purpose of ETV is to provide such data and information to the customer groups that require them in order to accelerate the real world implementation of improved technology. This paper describes the ETV approach and two recently initiated pilot programs for verification testing of wet‐weather flow and source water protection technologies.

Select this Article		EPA's Watershed Management and Stormwater Modeling Research Program Michael Borst and Marie O'Shea ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)197 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Watershed management presumes that community groups can best solve many water quality and ecosystem problems at the watershed level rather than at the individual site, receiving waterbody, or discharger level. After assessing and ranking watershed problems, and setting environmental goals, watershed management options can be analyzed. This analysis typically considers system constraints, cost‐effectiveness, the probability of meeting the watershed goal, the time required to achieve the goal, and the likelihood of a sustained change. Watershed management research at ORD's National Risk Management Research Laboratory's (NRMRL) address the following question: what effective watershed management strategies are available and how do communities select the most appropriate subset from these to match specific watershed needs? Watershed managers rely on various tools to enumerate, evaluate, and select management options. An important tool available to evaluate the array of available management alternatives available is a decision support system, i.e., a collection of approaches enabling water resource planners to select consistent, appropriate interventions with reasonable a priori estimates of their effectiveness. NRMRL watershed management research is creating a set of holistic, adaptive tools that enable local communities to select cost‐effective approaches to protect or restore the water resources within their watershed. NRMRL's research concentrates on identifying, collating, and developing techniques with associated data on cost, efficiency, execution, performance, and longevity emphasizing approaches likely to be within the pooled resources of watershed managers coupling flexibility with incremental quality improvements that allow adaptive management.

Select this Article		Overview of EPA's Wet‐Weather Flow Research Program Daniel Sullivan, P.E. and Richard Field, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)198 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an overview of the Environmental Protection Agency's (EPA's) wet‐weather flow (WWF) research program, which was expanded in October 1995 with the establishment of the Urban Watershed Management Branch at Edison, New Jersey. Research priorities for 1999 are presented as well as efforts to collaborate with other government organizations and professional societies. The branch is in the Water Supply and Water Resources Division (WSWRD) of EPA‐ORD's National Risk Management Research Laboratory. In November 1996, it issued the “Risk Management Research Plan for Wet Weather Flows” (EPA/600/R‐96/140), a peer‐reviewed plan which emphasizes the risk management aspects of urban WWF problems and anticipated research directions for the next five years. EPA divided the research plan into five major areas, each discussing a specific WWF problem and the anticipated research approach to solve the problem. The five research areas are: characterization and problem assessment, watershed management, toxic substances characterization and control, control technologies, and infrastructure improvement. Within each area, the state‐of‐the‐art knowledge is presented and the unknowns cited; research questions to address the unknown are also posed. An update of the 1996 research plan will be issued in 1999. In the time since November 1996, other organizations, notably the Water Environment Research Foundation (WERF), have reviewed WWF research programs and developed associated research needs reports. EPA endorses these efforts and views collaboration as essential in times of limited resources.

Select this Article		Combining New Technologies with Computer Modeling to Prevent Sanitary Sewer Overflows Resulting from Urban Rainfall Induced Peak Flow Conditions — The Miami‐Dade Water and Sewer Department Experience Marc P. Walch, P.E., Thomas J. Christ, P.E., and William M. Brant, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)199 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The United States Environmental Protection Agency (EPA) and the Miami‐Dade Waster and Sewer Department (MDWASD) (Miami, Florida) negotiated a Consent Decree settlement, which required them to undertake the installation and maintenance of a computerized collection and transmission system model. The “Virtual Dynamic Computer Model” has the ability to predict potential sanitary sewer overflows resulting from peak flow conditions. The system discharges flow to three wastewater treatment plants, which collectively treat up to 325 MGD (1.23 × 10⁶ m³/d). MDWASD's sewer collection and transmission system (“System”) consists of approximately 1,500 miles (2,414 kilometers) of force main, 2,500 miles of gravity sewer (4,023 kilometers) 1,000 MDWASD pumps, repump and booster stations, and also receives flow from approximately 1,000 private pump stations. The county is bounded to the north by Broward County, to the west by the Everglades, and to the east and south by Biscayne Bay (both of which are extremely sensitive environmental bodies).

Select this Article		High‐Rate Disinfection Techniques for Combined Sewer Overflow Mary K. Stinson, Izabela Wojtenko, and Richard Field, M.ASCE, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)200 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an overview of high‐rate disinfection technologies for combined sewer overflow (CSO). The presented high‐rate disinfection technologies depend on: ultraviolet light irradiation (UV), ozone (O₃), chlorination/dechlorination (Cl₂), chlorine dioxide (ClO₂), peracetic acid (PAA or CH₃COOOH), and high‐voltage electron beam irradiation (E‐Beam), respectively. Discussions of the technologies include: commercial availability and extent of use, state‐of‐development when not commercial, and where available, performance data and cost of either full‐scale or pilot‐scale installation. Also discussed is utility of increased mixing in concert with any disinfection technology. Disinfection of CSO is generally practiced to control the discharge of pathogens into receiving waters. Therefore, the disinfectant used at a facility for treatment of CSO should be adaptable to intermittent (dry and wet weather flow) use. Other considerations include effectiveness, oxidation rate, safety, and cost. Commonly used disinfection by chlorination forms toxic residual byproducts. Newer disinfectants such as UV, ClO₂, O₃, CH₃COOOH, and E‐Beam have a far lesser potential to generate toxic byproducts. Since CSO flowrates and volumes are significantly greater than dry weather flows, use of high‐rate processes requiring less tankage and space is more cost‐effective than use of conventional processes. High‐rate disinfection can be accomplished by: (1) applying mixing energy, (2) increasing disinfectant concentration, (3) using faster acting oxidants, (4) using high‐energy irradiation, or (5) using combinations of these. Use of increased mixing with any disinfection technology provides better dispersion of the disinfectant and forces disinfectant contact with a greater number of microorganisms per unit time. The increased rate of collisions decreases the required contact time, which enables a high‐rate disinfection.

Select this Article		A Protocol for Determining WWF Settling Velocities for Treatment Process Design Enhancement T. P. O'Connor, J. Cigana, and D. Fischer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)201 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A new settling testing method is compared to a traditional test in a laboratory side‐by‐side evaluation. The newer, smaller column settling test is thought to be more amenable for field use because of ease of transport and sampling, and the limited number of samples generated. The comparison attempted to determine whether these tests can capture the rapidly settling particles in wet‐weather flow. Measurements of suspended solids and the sample time were used to calculate percent removals. A summary of the performance as measured by predicted percent removal of the columns for 15 laboratory bench‐scale tests are presented and compared. The limitations and advantages of each approach are also discussed.

Select this Article		Stormwater Impacts on Ground Water Quality via Detention Basins David Fischer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)202 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Use of stormwater retention and detention basins has become a popular method for managing urban and suburban stormwater runoff. Infiltration of stormwater through these basins, however, may increase the risk to ground‐water quality, especially in areas like the Coastal Plain of southern New Jersey, where the soil is sandy and the water table shallow, and contaminants may not have a chance to degrade or sorb onto soil particles before reaching the saturated zone. Ground water from monitoring wells installed in basins in Camden and Gloucester Counties, New Jersey, was sampled and analyzed for volatile organic compounds (VOCs), pesticides, nutrients, and major ions. Results of analysis of these detention‐basin samples were compared to “background” ground‐water quality at sites in areas of “new‐ruban” land use. Initial results show elevated concentrations of some ions and nutrients, but VOC and pesticide concentrations did not differ greatly from background concentrations found elsewhere in the area. Dissolved‐oxygen concentrations in detention‐basin samples were considerably lower than background levels.

Select this Article		Sewer and Tank Flushing for Corrosion and Pollution Control Chi‐Yuan Fan, M.ASCE, P.E., Richard Field, M.ASCE, P.E., William C. Pisano, M.ASCE, P.E., James Barsanti, M.ASCE, P.E., and James J. Joyce, M.ASCE, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)203 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents an overview of causes of sewer deterioration concurrently with a discussion of control methods that can prevent or arrest this deterioration. In particular, discussed are inline‐ and combined sewer overflow‐ (CSO) storage‐tank‐flushing systems for removal of sediments and minimizing hydrogen sulfide production and associated corrosion. During low‐flow dry‐weather periods, sanitary wastewater organics and solids deposited in combined sewer (CS) systems can generate hydrogen sulfide and methane gases due to anaerobic conditions. Sulfates are reduced to hydrogen sulfide gas which can then be oxidized to sulfuric acid on pipes and structure walls by further biochemical transformation. Furthermore, these solids deposits or sediments are discharged to the urban streams during storm events which can cause degradation of receiving‐water quality. Thus, dry‐weather sewer sedimentation not only creates hazardous conditions and sewer degradation but contributes significant pollutant loads to the urban receiving waters during wet‐weather high‐flow periods. Performance of two technologies, i.e., the tipping flusher and the flushing gate was evaluated by a detailed examination of 18 facilities in Germany, Canada, and United States. As a result, both the tipping flusher and flushing gate technology appear to be the most cost‐ effective means for flushing solids and debris from CSO‐storage tanks, while the flushing gate is considered to be the most efficient method for flushing large diameter, flat sewers. In addition, cost‐effectiveness analysis was conducted for an actual project under construction, comparing flushing gate technology versus conventional large pipe cleaning operations using bucketing methods.

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WATER RESOURCES APPLICATIONS

Select this Article		Development of Water‐Resources Planning Models in England with Special Reference to Environmental Issues Mehmet Ali Yurdusev ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)204 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract History of water‐resources planning for England and Wales in England exhibits a good example in terms of both the methods used and their applications. Early modelling studies date back to the sixties. Since then several models have appeared, three of which in this paper have been reviewed. By emphasising how the environmental issues being treated, the applications of the models to the whole country are mentioned.

Select this Article		Future Data Collection Needs on Water Supply Reservoirs Saša Tomi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)205 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In the 20^th century, a tremendous amount of effort has been devoted to development and improvement of flood frequency analysis (FFA) methods. In spite of the resulting volume of research, there has still not been a general consensus on the best way(s) to develop flood frequency curves for regulated streamflows. Because a sample of regulated streamflows is not homogeneous, the present statistical methods of FFA are not appropriate. On the other hand, the deterministic methods, based on rainfall‐runoff modeling, suffer from the ‘loss‐of‐variance’ problem. This paper presents an evaluation of future reservoir data collection programs needed for the solution of the regulated FFA problem using a new deterministic‐stochastic approach, also discussed in the paper. The paper starts with an evaluation of the reservoir data that is collected currently at dams and reservoirs. We have contacted more than 20 agencies that are involved in reservoir data collection or in operation/maintenance of dams. For each agency, we have evaluated what data is collected, at what frequency the data is collected, and how the data is stored. Using the results of the data availability study, a Monte Carlo simulation was developed employing the new deterministic‐stochastic solution methodology. The simulation uses a reservoir routing module as the deterministic part of the solution framework, and the variation in reservoir initial and boundary conditions, as well as randomness in the reservoir inflow as the stochastic component. The results of the simulations indicated that additional reservoir data is needed for the use in this solution framework. While most agencies collect data on individual outlet gate settings and discharges, these data are usually maintained only in hard‐copy form, and thus are not readily available for use in computer modeling. However, this data is necessary for the definition of probability distributions of reservoir boundary conditions.

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GROUNDWATER MEASUREMENT ISSUES

Select this Article		Quantifying Ground‐Water Pumping Impacts on Surface Water in Idaho Gary S. Johnson and Donna M. Cosgrove ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)206 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Idaho has embraced the concept of conjunctive management and the administration of surface and ground water rights in a common priority system. The means for quantifying impacts of ground water use on surface water resources is currently being developed. The process is complicated by the widespread effects of ground water use and the high degree of temporal attenuation of effects. One possible quantification method relies on the development and application of response functions. Response functions describing the temporal variation in river gains and losses resulting from ground water use have been developed from a numerical ground water flow model of the Snake River Plain aquifer. Response functions describing impact on each of several reaches of the Snake River are being aggregated to form zones throughout the aquifer. The response functions are proving to be useful educational tools for water users and managers and will be instrumental in the development of plans for mitigating ground‐water pumping impacts on senior surface water users.

Select this Article		Generating Groundwater Vulnerability Indices in North Carolina Using GIS Emmanuel U. Nzewi, A.M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)207 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper presents a method for generating groundwater vulnerability assessment indices. In this particular study, potential and current groundwater sources in North Carolina are addressed. The general definition for groundwater vulnerability to contamination is “The tendency or likelihood for contaminants to reach a specified position in the groundwater system after introduction at some location above the uppermost aquifer.” According to the First Law of Groundwater Vulnerability, all groundwater is vulnerable. Therefore, the likelihood of contamination of a given body of groundwater is an important statistic if it can be reasonably assessed. In fact, such a measure could be used in several ways. For example, it could be used as a guide for planning the use of a piece of land or as an index for the development of a decision support system for managing operations that may result in groundwater contamination. Furthermore, a vulnerability index could be used as a planning guide in developing strategies for the protection of critical sources of (ground) water supply. With regards to management, vulnerability indices could be used in the development of best management practices for regional water supply systems. In such a case, practices that could result in groundwater contamination may be so managed that they collectively present the lowest risk possible to the underlying groundwater sources. In this study, a geographic information system (GIS) is used to manage hydrogeologic information and other data (related to groundwater use) in developing regional vulnerability indices for North Carolina. Several factors considered in the generation of vulnerability indices are discussed.

Select this Article		Formulating the Subsurface Flow from the Sloping Valley Bed Alluvium E. Khazai ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)208 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper describes the investigation which was carried out for formulating the subsurface flow from the alluvium forming the valley beds in the mountainous areas of the catchments in south east of Iran. The formula has a useful application in the conceptual model developed by the author for estimating the groundwater recharge in the region.

Select this Article		Electrical Imaging: An Old Technology Effectively Modernized Richard A. Hoover, CPGS and Jeffrey L. Leberfinger, P.G. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)209 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Electrical imaging represents a re‐emergence of an old technology. The technology has been hampered by high cost compared to other methods. However, through advances in field equipment design capability, and the development of computer algorithms necessary to effectively and accurately reduce and present the geophysical data, electrical imaging is now cost competitive with more commonly used geophysical techniques. The new and future applications of this technique for the efficient development of groundwater resources will change the way groundwater aquifers are exploited and managed.

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LINKING ENGINEERING & ECOLOGY: INTERDISCIPLINARY MODELING IN WATER RESOURCES

Select this Article		Linking Hydrodynamic and Ecological Models at Shasta Lake Laurel Saito, R. Blair Hanna, John Bartholow, and Brett Johnson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)210 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Water resources managers have long recognized that water management issues are inherently interdisciplinary. For this reason, effective water resources decisions require input from more than one discipline. For example, engineers monitor and regulate flows, fisheries biologists study fish populations, entomologists study aquatic insects, limnologists study l^lake chemistry, geomorphologists look at how flows alter and shape landscapes, and recreation managers are concerned with providing environments that satisfy recreationalists such as boaters and anglers. The interdisciplinary nature of water resources management means that decisions based on specific concerns in any one of these disciplines will have effects that concern other disciplines. While this may appear to some as an overwhelming circular maze of cause and effects, it is the premise of this paper that the expertise that has been built into each of these disciplines can be used in interdisciplinary approaches that link the existing knowledge together. This paper presents the development and application of a linked modeling approach at Shasta Lake that incorporates engineering and ecological models to address the interdisciplinary issue of managing reservoir releases to enhance downstream fish habitat, maximize hydropower production, and provide adequate in‐reservoir water quality and fishery conditions.

Select this Article		Including Long‐Term Biological Index Performance in a Multi‐Criteria Decision Support System Terry J. Waddle, M.ASCE, Zachary H. Bowen, and Ken D. Bovee ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)211 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract A Decision Support System (DSS) was developed for the reservoirs operated by the U.S. Bureau of Reclamation that incorporates biological resources in a palette of decision variables. A scoring technique was developed for the DSS to help to evaluate the long‐term effects of proposed reservoir system operations on those variables. The biological component of the DSS was developed to help Bureau of Reclamation reservoir operators evaluate the effects of different scenarios of reservoir operations on a variety of water‐related biological resources. In this DSS, Reclamation's Reservoir Operations Modeling System (ROMS) is linked to modules evaluating power production, flood control benefits, irrigation water deliveries, municipal and industrial water supplies, habitat for endemic fish communities, tailwater fisheries, nesting habitat for shorebirds, reservoir recreation, reservoir fisheries, and regeneration of riparian cottonwood forests. Operation scenarios generated in ROMS are scored for each decision variable by comparison to a target range of a decision variable for a reference location and time period. The score for a variable is calculated based on the ratio between the percent of time that target conditions are met under alternative operating conditions and under the reference condition, respectively. A scoring technique was developed that recognizes that under either natural or highly managed conditions the reference target is not met at all times. Higher scores are achieved for environmental decision variables by operations scenarios that approach natural seasonal and annual variability in habitat availability.

Select this Article		Restoration and Management of Western River Ecosystems: A Systems Impact Assessment Model for the Klamath‐Trinity River Marshall Flug, John Bartholow, and Sharon Campbell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)212 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In 1986 the US Congress took action to restore anadromous fisheries to optimum levels by the year 2006 in the Klamath River Basin of Oregon and California. This action created the Klamath River Fisheries Task Force which represents over sixteen water user interests within the basin. The US Geological Survey (USGS) interacts with this Task Force and others, including four Native American tribes, to develop a better scientific understanding of how water quantity and quality affect or limit anadromous fisheries restoration. The Western Riverine Ecosystems Research Team, within the USGS Midcontinent Ecological Science Center, has developed an integrated group of models for resource management. This System Impact Assessment Model (SIAM) is applied to the Klamath River of northern California and southern Oregon. SIAM consists of computer models describing water flow, water quality, fish habitat quantity and quality, anadromous fish populations, and economics. This paper describes the development, implementation, and transfer of SIAM for water management within the basin. Major goals of the modeling activities are to improve anadromous fish restoration, to assist with analysis of water management alternatives, and to help address upcoming Federal Energy Regulatory Commission re‐license applications.

Select this Article		Linking Hydrology and Ecology in Simulations for Impact Assessments Mark B. Bain and D. P. Loucks ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)213 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In a study of several small watersheds near Ithaca, NJ', we are attempting to simulate the impacts of land uses and water management on flow regime, water qualify, and the integrity of the aquatic and riparian biota. This paper describes the ecological indicators and suitability functions we are using to link hydrology and ecology, focusing on the stream habitats of our watersheds. We believe similar approaches may be applicable to the simulation of the changing states of the ecology of other watersheds as well.

Select this Article		HydroBasin™: Relicensing Planning for Hydroelectric Watersheds James R. Young, Scott Akenhead, Geoff Rabone, and Ed Gregr ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)214 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract We need a basin‐wide planning and multiple‐objectives optimization tool to manage the risks inherent in relicensing a complex network of hydroelectric facilities and to increase the probability of a successful outcome. The goal is to find the best‐suited and most cost‐effective locations for enhancing environmental and recreation benefits of the watershed while containing costs, reducing the risk of generation losses, and preserving existing hydro assets. Public involvement of stakeholders is critical for successful relicensing under Federal Energy Regulatory Commission (FERC) guidelines. HydroBasin, developed by Facet Decision Systems for EPRI and Southern California Edison (SCE), is a watershed planning tool that integrates models for systems operation, fisheries, recreation, and runoff prediction to create and evaluate watershed management scenarios. The model is designed for negotiation support with relicensing stakeholders. A new optimization method was developed based on “adaptive simulated annealing” but with conservation of mass within a network. HydroBasin finds the best places, according to stakeholder values, for fish and recreation while optimizing electricity revenue.

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ANALYSIS & MODELING RIVER SYSTEM WATER QUALITY

Select this Article		Modeling Phosphorus Uptake and Plant Growth Dynamics in an Urban River System: Application of the ECOL1 Model in the Grand River Basin, Ontario Alison Humphries and Isobel Heathcote ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)215 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Phosphorus dynamics are notoriously complex in most aquatic systems, yet can be central to a good understanding of eutrophication and dissolved oxygen phenomena. Most plant‐growth simulation models employ a lumped‐ or single‐species approach and thus are relatively crude predictive tools. Few attempt to incorporate the growth patterns of multiple species. One of these is ECOL, a plant‐growth model originally developed as a subroutine of the Grand River Simulation Model (GRSM) in the late 1970s. ECOL predicts the biomass, phosphorus uptake and oxgyen production of three types of aquatic plants: the attached alga Cladophora, the rooted aquatic plant Potamogeton, and periphyton. GRSM and ECOL were subsequently used in planning water management strategies for the Grand River Basin (Ontario) and its nine major municipalities in the early 1980s. In 1995, the Grand River Conservation Authority approached the University of Guelph to assist them in upgrading the ECOL model to reflect recent research on phosphorus dynamics and river ecology. In collaboration with researchers at the University of Waterloo (Department of Biology), researchers at the School of Engineering at the University of Guelph developed and tested new algorithms to improve the ways in which ECOL manages light, temperature, and phosphorus impacts on plant growth. The reconfigured model provides highly accurate simulations of plant growth phenomena in an important urban river system, as well as insights into the impact of phosphorus‐control measures in urban and agricultural systems.

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WATER CONSERVATION PRICING

Select this Article		Methods to Evaluate Conservation Rate Structures David M. Pekelney, Ph.D. and Thomas W. Chesnutt, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)216 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Evaluating a rate structure is an analytic activity that improves understanding of the consequences of rate structure choices. The appropriate amount of analysis depends on both the cost of conducting the analysis and the benefit derived from the analysis. Water agencies with stable system costs and demands may need to invest less in evaluation. Water agencies facing rapidly changing system costs, demands, or other significant uncertainties may need to invest more in evaluation. In general, we aim to reduce the cost and increase the benefits of rate structure evaluation.

Select this Article		The Chilean Water Market System and Obstacles to Efficient Water Use Matthew D. Davis and Jay R. Lund ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)217 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The formal water market system in Chile is presented, focusing on obstacles to economically, environmentally, and socially efficient use of water. In Chile water resources availability varies substantially by longitudinal location, with arid and semiarid conditions in the north and center of the country, the principal areas of population and economic activity. Water distribution management is characterized by broad private‐sector involvement based on historical participation in agricultural communities and reinforced in the Water Code of 1981, which encourages market transactions to redistribute water. Other water management sectors are less developed. The overall water resources management system is subject to weak and fragmented oversight by numerous government institutions that sometimes have competing and overlapping responsibilities. Water market transactions have been limited in magnitude due to physical limitations, an incomplete economic framework, administrative difficulties, weaknesses in other management sectors, and social attitudes. In addition, environmental concerns and social cost are not directly considered in the present system. Water markets can serve to redistribute water where it is scarce and there is competition for the resource. However, a comprehensive supportive framework must be in place to assist free water market transactions, one that addresses the multiuse nature of water and that considers economic, environmental, and social objectives.

Select this Article		The Optimal Nonlinear Pricing Rules for Water Services J. C. Elnaboulsi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)218 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this article is to determine the optimal nonlinear pricing rules for water services. The model presents a standard water distribution system and a separate wastewater collection and treatment system. Technical and financial constraints are considered. The optimization process of a welfare utility function subject to different kind of constraints provides the optimal pricing rules for drinking water and sewerage services. These prices reflect efficiently the costs of systems constraints, the cyclicity of demands, the time‐of‐use, heterogeneity types of consumers and the real value of water resources scarcity. They provide important guidance in the design of efficient water rates and in the development of different water utilities planning strategies. New technologies in water metering (telemetry) should permit applying this model.

Select this Article		What Can We Learn About Water Services Management and Privatization in France? J. C. Elnaboulsi ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)219 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The water industry is largely a natural monopoly. Water distribution and sewerage services are characterized by networks and its natural monopoly derives from the established local networks of drinking water and sewers. In France, local communities have a local requirement of providing public services and subject to respect different kind of standards in terms of water quality and level of services. They are responsible for producing and distributing drinking water, and collecting and treating wastewater. Furthermore, the French water utilities are required to be financially self‐sufficient. Rate‐setting varies across regions and local territories due to a variety of organizational features of services and availability of water resources. The management of these local public services can be public or private: local governments have the right, by the constitution, to delegate water service management to private companies which operate under the oversight of local municipal authorities. Different reasons are responsible for the poor performance and low productivity of most French public water utilities. Many public water utilities have looked for alternative ways to provide water and sanitation services more efficiently, to improve both operational and investment efficiency, and to attract private finance. The purpose of this paper is to present the French organizational system of providing drinking water services, and collecting and treating wastewater services: legal aspects, contracts of delegation, and competition.

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DESIGN ISSUES IN USER INTERFACES: EXPERIENCES

Select this Article		Negotiating a User Interface David Moser, Michael Walsh, and Cory Rogers ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)220 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The Institute for Water Resources (IWR) of the US Army Corps of Engineers provides research and development services to organizations within the Corps of Engineers. Over time, IWR has developed a variety of computer programs for internal and external use. In general, the problems that are addressed by these systems are complex. The solutions require large amounts of data as input and can generate large amounts of data as output. Many potential users are unfamiliar with the basic concepts embodied in both the problem and the solution. Further, understanding of the problems has grown over time, and users have requested enhancements and modifications, requiring continual revision in the programs. The user interface of each model has changed over time, starting out as simple, DOS‐based text and file interfaces, then evolving to 16‐bit and 32‐bit Windows applications using relational database technology. The user interfaces are developed through a series of negotiations between developers and clients/users, involving trade‐offs between clarity and capabilities of the interface, features of the simulation model, and the time and effort required to develop the interface.

Select this Article		Graphical User Interfaces for HEC NexGen Programs — Concepts and Commentary William Charley, Lisa Pray, and Gary Brunner ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)221 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The U.S. Army Corps of Engineers Hydrologic Engineering Center's NexGen software modernization project has recently fielded two major hydrologic/hydraulic modeling computer programs and is in the process of developing several more. The programs make extensive use of graphical user interfaces in obtaining complex data input from the user in order to perform their simulations. A prime objective in the development of these programs was to allow new users to rapidly understand and interpret data, while not restricting experienced users. This paper describes the experiences and lessons learned in the Center's modernization project.

Select this Article		Operations Control Language (OCL™): The Key to a Flexible Planning Model Daniel P. Sheer, Anthony P. Pulokas, Jeffrey K. Meyer, Dean Randall, and Harold W. Meyer ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)222 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Most current modeling tools of water resources systems are limited by the ability to program operating rules. The authors have been able to create a highly generalized tool by developing the Operations Control Language (OCL™). With this language, a modeler controls the forms of the operating rules in the model, not just the parameters. This approach is simple and natural because the rules are fed into a mixed‐integer linear programming algorithm. Thus, the rules that a modeler writes only specify what objectives and constraints drive the operation; they do not have to specify how the objectives and constraints are met. This approach has been developed from the authors' experience modeling a wide variety of water resources systems. The authors have given the language features that will best enhance its role in a highly generalized tool, including commands that allow the operations model to run in parallel other models.

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SOUTHWEST CLIMATE ASSESSMENT PROJECT

Select this Article		Climate Assessment Project for the Southwest R. Bales, B. Morehouse, and D. Liverman ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)223 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract CLIMAS, the Climate Assessment Project for the Southwest, was established in 1998 with seed funding from the National Oceanic and Atmospheric Administration (NOAA) to assess climate variability and longer‐term climate change in terms of impacts on human and natural systems in the Southwest. The project's mission is to improve the ability of the region to respond sufficiently and appropriately to climatic events and climate changes. CLIMAS aims to foster participatory, iterative research involving researchers, decision makers, resource users, educators, and others who need more and better information about climate and its impacts. In support of these efforts, the project fosters research on the nature, causes, and consequences of climate change and variability in the Southwestern U.S., and supports efforts to improve climate and hydrologic forecasting in the region. CLIMAS is part of a larger initiative to develop better‐quality and more‐detailed climate assessments at the regional level. To this end, the project, which is housed within the Institute for the Study of Planet Earth at the University of Arizona, supports interdisciplinary research on past, current, and future climates in the region and provides a focal point for identifying and serving the information needs of stakeholders at the local, state, national, and international levels. CLIMAS brings together researchers who study the processes and effects of climate on the Southwest region with individuals and organizations who need climate information to make informed decisions. The initial focus of CLIMAS is on: i) working with stakeholders to identify and evaluate climate information and forecast needs and products, ii) supporting research on physical characteristics and processes, iii) supporting research on human and ecological impacts, iv) providing Southwest climate information and forecasts to people in the public, private, and non‐profit sectors, and v) participating in climate assessment activities carried out in other regions and by various governmental entities.

Select this Article		Assessing Climate Variability in the Southwest: State of the Science Andrew C. Comrie, Paul R. Sheppard, Gregory D. Packin, Kurt Angersbach, and Malcolm K. Hughes ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)224 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Dry, and hot! For many, these two words sum up the climate of the southwestern United States. The region's low deserts experience searing heat and desiccating winds in the early summer while, in contrast, the forested mountains and plateaus endure biting cold and drifting snow in the heart of winter. The Southwest may be drenched by torrential monsoon thunderstorms in July and August, yet it can warm gently under fair skies from fall to spring. Records of temperature and precipitation change span time scales shorter than seasons and longer than millennia. Droughts and floods that would make headlines elsewhere are almost routine in the Southwest. Variability is therefore the norm, and climate is always fluctuating within this region. How do we explain the complex climate of the Southwest? How has it changed over time, and what might we expect of future climate? In this paper we aim to answer these and related questions to produce an account of the current state of knowledge of natural climate variability in the Southwest. Specifically: What is our understanding of climate variability in the Southwest on seasonal to inter‐decadal time scales and what are the sources of this variability? What are the major patterns or types of variability evident from the instrumental record and natural archives such as tree rings, in terms of extremes, drifts in mean, trends or periodic and quasi periodic features? How typical has the instrumental period (i.e., the 20th century) been in the context of these patterns from natural archives?

Select this Article		Assessing the Vulnerability of the Southwest's Urban Water Sector to Climate Variability Rebecca H. Carter, Petra Tschakert, and Barbara J. Morehouse ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)225 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Climate variability at the seasonal, interannual and inter‐decadal time scales can be an important factor in management of urban water resources in the Southwest, yet little research on the nature and magnitude of climate impacts on that sector has occurred to date. This paper discusses a methodological framework for assessing the sensitivity of water supply and demand in five Arizona communities to variations in precipitation, and presents some preliminary findings from the assessment.

Select this Article		Water Resources Simulation in the Rio Grande Basin Using Coupled Models Everett P. Springer, C. Larrabee Winter, and James E. Bossert ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)226 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Regional assessments of water resources under global climate change require models that can resolve management, land use, and climate effects. Los Alamos National Laboratory is developing a coupled model of water resources that places a river basin in its global context. The upper Rio Grande basin above El Paso, Texas is the testbed for this model. The model structure and computational approach are emphasize and issues such as nonlinear feedback between components and spatial and temporal scaling of processes are discussed. Using simulations of regional meteorology, the effects of high spatial resolution simulations on the distribution of precipitation are demonstrated.

Select this Article		Seasonal Forecasts and Water Management in Arizona: A Case Study of the 1997–98 El Niño Event Thomas C. Pagano, Holly C. Hartmann, and Soroosh Sorooshian ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)227 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 1997–98 El Niño provided a unique opportunity for climate information and forecasts to be utilized by water management agencies in the Southwestern U.S. While Arizona has experienced high streamflow associated with previous El Niño events, never before had an event of such magnitude been predicted with advance warning of several months. Likewise, the availability of information, including Internet sources and widespread media coverage, was higher than ever before. Insights about use of this information in operational water management decision processes are developed through a series of semi‐structured in‐depth interviews with key personnel from a broad array of agencies responsible for emergency management and water supply, with jurisdictions ranging from urban to rural and local to regional. The interviews investigate where information was acquired, how it was interpreted and how it was incorporated into specific actions. The interviews also investigate agency satisfaction with the products available to them, their operational decisions, and intentions to utilize forecast products in the future. Study findings lead to recommendations about how to more effectively provide intended users of forecasts with information required to enact mitigation measures and utilize opportunities that some climatic events present.

Select this Article		Weather, Climate, and Hydrologic Forecasting for the Southwest U.S. Holly C. Hartmann, R. Bales, and S. Sorooshian ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)228 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In support of the Climate Assessment (CLIMAS) Project for the Southwest, a review was conducted of the current state of weather, climate, and hydrologic forecasting for the Southwest. A key element of the review was a workshop that examined the availability, use, accuracy, and value of forecasts, with participants consisting primarily of agency personnel involved in operational forecasting via directly issuing forecasts, providing key data for making forecasts, or serving as a key link for communicating forecasts. The broad range of forecast products encompasses myriad variables, time‐scales from minutes to seasons, and lead‐times from minutes to over a year. Current forecast products and techniques are reviewed, and implications for use in decision making are discussed. The forecast review identified needs for additional research to be addressed by the CLIMAS Project, including local evaluation of monthly and seasonal climate outlooks, retrospective evaluation of operational water supply outlooks, hindcast reanalysis of probabilistic water supply outlook techniques, and incorporation of climate outlooks into statistical water supply outlook techniques.

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ECONOMICS OF STORMWATER MANAGEMENT

Select this Article		Integrated Flood Planning with Risk‐Based Optimization Jay R. Lund ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)229 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The economical integration structural and non‐structural flood control options is a long‐standing problem in water resources planning and management. A two‐stage linear programming formulation of this problem is proposed and demonstrated which provides an explicit economic basis for developing integrated flood control plans. The approach minimizes the expected value of flood damages and costs, given a flood frequency distribution. A wide variety of structural and non‐structural management options can be examined in the method, and interactive effects of options on flood damage reduction can be represented. The approach is demonstrated and discussed for a realistic hypothetical example. Limitations of the method also are discussed.

Select this Article		Costs‐Benefits Analysis for Flood Defense Works P. Mazzalai and F. Garzon ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)230 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract When we plan a floods‐protection work as dams or embankments, it should be necessary to evaluate which dimensions give rise to the lowest costs‐benefits ratio; this study gives an innovative analytic solution to this important and complex question.

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ECOSYSTEM RESTORATION ALONG THE SALT RIVER: CHALLENGES & SUCCESSES

Select this Article		The Ecosystem Restoration Program of the Corps of Engineers: Case Study along the Salt River in Phoenix and Tempe Area Mike Ternak, Alex Watt, and James Chieh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)231 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Ecosystem restoration represents a non‐traditional approach to civil works projects conducted by the Corps of Engineers. This paper describes the increased momentum that the Corps' restoration program has gained over the last 5 years, and highlights a case study in the Arizona area. Under Senate Appropriations Bill H.R. 2445, U.S. Army Corps of Engineers, Los Angeles District conducted a feasibility study of the water resources problems and opportunities along the Salt River in the Phoenix and Tempe metropolitan area of Maricopa County, Arizona. Upon initiation of the feasibility effort, the entire 33 mile reach studied under the reconnaissance phase was evaluated for potential environmental restoration. Two specific sites were identified which would be of immediate interest in an environmental restoration construction project. The first site, Tempe Reach, is located in Tempo, Arizona, on portions of the Indian Bend Wash and Salt River. The second site, Phoenix Reach, is located entirely in the Salt River within the City of Phoenix. The total length of the Phoenix Reach is approximately 5 miles. A number of habitat restoration alternatives were developed in cooperation with the non‐Federal sponsor and evaluated relative to their effectiveness, acceptability, and incremental economic and ecosystem output efficiency. The alternative selected would provide riparian habitat, marginal surface and groundwater quality improvement from well‐head treatment and the natural filtering ability of wetland vegetation, and incidental flood control and recreational opportunities.

Select this Article		Death to Rule Curves Charles D. D. Howard, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)232 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The purpose of this paper is to focus attention on the potential for increasing the benefits from existing dams. Some reservoirs are operated by controlling releases to maintain reservoir water levels within established bounds that depend on the time of year. These time dependant bounds, or “rule curves”, are determined by office studies that may have evolved many years ago during the design of the dam. Rule curves have one advantage ‐ simplicity for the operator of the dam. They can have two disadvantages ‐ disregard for present circumstances of weather and watershed conditions, and lack of a clearly defined objective function. In general, rule curves displace opportunities for optimization with a blind constraint. In specific cases, rule curves can be arrogant artifacts that restrict discretion, wisdom, experience, and effective use of real‐time data. The alternative is to provide operators of river systems with decision support systems that recommend current reservoir releases based on currently observed data and computer models that will satisfy constraints and maximize an objective function. This paper describes how such models are developed and two of the applications where they have been implemented.

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LONG TERM FORECASTING & WATER RESOURCES SYSTEMS OPERATIONS

Select this Article		Hydrometeorologic Forecasting at Salt River Project—1999 Jon Skindlov, Dallas Reigle, Charles Dempsey, Tim Skarupa, Yvonne Reinink, and Charles Ester ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)233 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Salt River Project (SRP), through its Water Resource Operations division, manages six reservoirs with a storage capacity of about two million acre‐feet on the 13,000 square mile Salt‐Verde watershed in central Arizona. Long‐range models and conditions in the tropical Pacific Ocean provide an initial outlook of winter precipitation and runoff. During the runoff season (primarily December through March), several meteorological models are consulted daily to anticipate weather at the medium‐range (3 to 10 days out) and to produce short‐range (out to 48 hours) weather forecasts. Hydrologic storm runoff models utilizing forecast precipitation and snow level produce a forecast hydrograph for each basin. Storms in Arizona are tracked by a variety of weather and hydrologic sensors. Throughout the winter, snow accumulation is measured every two weeks. SRP and two Federal agencies arrive at semi‐monthly consensus seasonal runoff forecasts after consulting several water supply forecast models. SRP's Project Reservoir Operations Planning (PROP) committee uses this information when making reservoir operation decisions. SRP has found the coordinated use of numerical and statistical models essential for the safe and efficient management of the Salt‐Verde reservoir system.

Select this Article		Long Term Probabilistic River Forecasting Applied to International Integrated Water Management Projects Curtis B. Barrett ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)234 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The National Oceanic and Atmospheric Administration (NOAA), National Weather Service (NWS) is transferring National Weather Service hydrometeorological forecast system technology to many countries throughout the world. The demand for NWS technology continues to increase due to an increasing stress on freshwater resources, that is caused by a continuing increase in water demand among various types of water uses and complicated by growing pollution. Conflicts in water use transcend local, regional, country and transboundry levels. The NWS is transferring the National Weather Service River Forecast System (NWSRFS) to Panama, Mexico, and South Africa. These countries have recently experienced severe droughts and floods, and are determined to manage their existing water resources more effectively. Application of long term probabilistic forecasting capability is an important step in achieving optimal management of water supplies. The NWSRFS is a computer system consisting of many software modules which perform various hydrologic, hydraulic and data management operations to forecast streamflow. NWSRFS includes the Calibration System, Operational Forecast System, Interactive Forecast Program, and the Ensemble Streamflow Prediction (ESP) component. The ESP uses conceptual hydrologic/hydraulic models to forecast future streamflow using the current snow, soil moisture, river, and reservoir conditions and historical meteorological data. The ESP system assumes that meteorological events that occurred in the past are representative of events that may occur in the future. Each year of historical meteorological data is assumed to be a possible representation of the future events and is used to simulate a streamflow trace. The simulated streamflow traces can be scanned for maximum flow, minimum flow, volume of flow, reservoir stage, etc. for any period in the future. Applications for ESP for water management have proven quite effective in improving longterm water management.

Select this Article		Simulation Analysis Using RS and NPS Modeling as an Integrated Tool H. W. Chen and Ni‐Bin Chang ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)235 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Due to rapid economic growth in Taiwan, the role of reservoir watershed management is changing from water resources conservation toward the maximization of land‐use potential that may further endanger the reservoir water quality from a long‐term perspective. Recent concern of sustainable development in reservoir watershed focus on the identification of watershed land‐use program for preventing the impact of nonpoint source pollution from the deterioration of reservoir water quality. To achieving this purpose, the state‐of‐the‐art 3'S information technology by properly integrating remote sensing (RS), geographic information system (GIS), and global positioning system (GPS) is viewed as an important tool for reservoir watershed management. SPOT images were found to be useful in identifying land cover types. Substantial effort of this study will be placed upon the integration of non‐point source pollution modeling and remote sensing technology in order to estimate the potential impact to reservoir water quality due to various land‐use programs in Tseng‐Wen reservoir, south Taiwan. The use of 3'S information technology is proven as a promising approach in this study and the management strategy for seven types of land‐use patterns for non‐point source pollution control can be easily figured out based on such an analytical approach. However, illegal cultivation of beetle nut cannot be distinguished at the present stage. But it will be critical for land cover change and evolution in the reservoir watershed study in Taiwan in the future

Select this Article		An Optimal Neural Network Model for Daily Water Demand Forecasting Joong H. Kim, M.ASCE, Seok H. Hwang, and Hyun S. Shin ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)236 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract An optimal neural network model for daily water demand forecasting is presented. It has been reported that variation of water demand is related to the weather. A number of researches have shown that the relationships between daily water demand and exogenous variables usually are nonlinear. However, the majority of the short‐term water demand forecasting models published have treated the daily water demands as a stochastic time series, and described the relationships by using linear expressions. This study tackles the complexity of the relationship between daily water demands and exogenous variables. In an effort to more effectively forecast the daily water demands, a neuro‐genetic algorithm is adopted in this study, which is a combination of the Neural network and the Genetic algorithm. Temperatures, previous day's water demand, sunshine‐duration period, and day type have significant impact on the daily water demand forecasting. If only one input parameter is to be used, a model which uses previous day's water demand as an input parameter shows the best results. Among all the models tested in this study, a neuro‐genetic model with input parameters of two previous days' demands and today's and yesterday's average temperatures shows the best performance in today's water demand forecasting. It is recommended that a number of models with various input parameters be tested before any particular model is adopted for a specific service area.

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REAL TIME DATA ACQUISITION, TRANSMISSION, MANAGEMENT, & DISPLAY

Select this Article		Data Acquisition for Hydroelectric Operations Charles D. D. Howard, M.ASCE and Douglas I. Smith ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)237 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Efficient operation of hydroelectric systems requires a decision support system of hardware and software. The purpose of the decision support system is to acquire data and to increase its information content. This purpose is achieved by computer programs that minimize the manual input required by busy hydroelectric operators and suggest recommendations for good operating decisions that recognize all of the factors involved in a current situation. This paper briefly describes the HYDROPS decision support system and focuses on the satellite downlink hardware and software which is used for data acquisition, display, and editing.

Select this Article		Managing and Distributing Real‐Time and Archived Hydrologic Data from the Urban Drainage and Flood Control District's ALERT System Kevin G. Stewart, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)238 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Background information will be provided on the development of early flood detection networks and local flood warning programs in the Urban Drainage and Flood Control District. With seven basin flood warning plans currently supported by the District, the automated gauges associated with these plans now total more than 140 stations with over 260 sensors providing continuous real‐time measurements of rainfall, water level, wind, temperature, humidity, barometric pressure and other parameters. Many public safety and public works agencies in the Denver, Colorado area are provided with free dial‐up access to this system, commonly known as the ALERT System (Automated Local Evaluation in Real‐Time). Two Denver television stations also routinely access the ALERT system to provide their viewers with current rainfall and flood information, and to increase the chance that their camera crews will be first on the scene for live storm coverage. ALERT data is also heavily used during non‐flood times for fire weather, stormwater quality monitoring and other alternative applications. With the demand for this data continuing to increase, Internet access was added in 1998. The District expects many users will soon prefer this data communications option. This paper will focus on how improved computer graphics and the data communication technologies of the information age have led to a renewed interest in an early flood detection system that has been serving the public well for 20 years.

Select this Article		Radar‐Based Precipitation Processing for NWS Hydrologic Forecast Services Dennis A. Miller, Jay P. Breidenbach, Richard A. Fulton, and Dong‐Jun Seo ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)239 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The National Weather Service (NWS) runs an operational, multi‐stage, precipitation processing system which determines rainfall accumulation estimates over a variety of spatial and temporal scales for use in forecasting, warning and numerical modeling applications and for dissemination to the general public. The primary input data to this system are radar reflectivity factor returns provided by the Weather Surveillance Radar‐1988 Doppler (WSR‐88D) radars of the Next Generation Weather Radar (NEXRAD) program. Since 1991 over 160 of these radars have been deployed, providing nearly contiguous coverage across most of the United States. Rain gage data are also incorporated at various stages of the system, principally to provide calibration of radar rainfall estimates. As the processing proceeds across NWS venues from a local to a regional to a national level, numerous quality control operations are performed, radar rainfall data are composited together spatially (“mosaicked”), and a wide variety of products are generated including alphanumeric, graphics‐display, and high‐resolution, digital‐data. The products, which are updated as often as every five minutes, provide guidance to forecasters and input to hydrologic and other numerical models. In some instances, they are made available to users outside the Weather Service, as well.

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CURRENT ISSUES & ACTIVITIES IN SPILL PREVENTION

Select this Article		Future Prospects for Spill Prevention Activity Andrew Dzurik, P.E., M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)240 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The issues and activities presented in this session suggest a rapidly growing recognition of the need to address spill prevention as an element of water resources management. Whereas we have developed a wide array of programs and technologies for cleanup and mitigation efforts, we are just in the early stages of developing adequate spill prevention programs and technologies. Recent examples of merchant marine, cruise lines and navy ships show that a substantial number of spills continue to occur throughout the world, and additional legal and technological attention is needed. A review of websites provides further evidence of problems and opportunities. This paper summarizes important successes and identifies opportunities for growth in this area in order to further our abilities to protect the nation's water resources. The paper is also intended as a focal point for discussion among session participants.

Select this Article		Secondary Containment Systems for Bulk Oil Storage Facilities in Region 5 Barbara A. Carr, Ph.D. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)241 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract In the past few years, several hundred facility inspections have been conducted for the Spill Prevention, Control and Countermeasures (SPCC) program in the six states within U.S. EPA's Region 5 (Illinois, Minnesota, Michigan, Ohio, Indiana and Wisconsin). The predominant violations/deficiencies cited for these facilities were 1) lack of a spill prevention plan; 2) lack of appropriate containment, diversionary structures or equipment to prevent discharged oil from reaching a navigable water course; 3) inadequate or permeable secondary containment or diversionary structures; and 4) lack of or an inadequate quick drainage system in the facility tank car or tank truck loading/unloading area. Preliminary results from a Liner Study conducted by the U.S. EPA indicates that there are several effective and feasible designs which can significantly improve the effectiveness and impermeability of secondary containment for aboveground storage tanks (AST). These include one or more of the following: the addition of a liner in the secondary containment, retrofitting the bottom of an AST with a second steel plate, using a geosynthetic liner on top of the original bottom, installing a leak detection system in the interstitial space between the steel plates, or installing an undertank liner with a leak detection system during construction of a new AST.

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CLIMATE VARIABILITY & CHANGE IMPACTS ON REGIONAL WATER RESOURCES

Select this Article		Implications of the El Niño‐Southern Oscillation for Long‐Range Streamflow Forecasting: The Columbia River Basin Thomas C. Piechota, M.ASCE and John A. Dracup, F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)242 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The increased demands of water users in the Pacific Northwest region of the United States has also accentuated the need for long range forecasts of streamflow. At present, long range streamflow forecasts are not available to water resource managers. Yet in the Pacific Northwest, a significant lag relationship exists between ENSO (El Niño‐Southern Oscillation) and streamflow. Using this lag relationship, this study proposes to extend the prediction of spring‐summer runoff in the Pacific Northwest from the current one‐ to three‐month lead time to a three‐ to seven‐month lead time. Presented here is the development of a long range seasonal streamflow forecasting model for the Columbia River Basin. The model uses, as predictors, Persistence in streamflow along with two ENSO indicators: the Southern Oscillation Index (SOI) and the Wright Sea Surface Temperatures (SST_W). A probabilistic streamflow forecast is made from an optimal linear combination of Persistence, SOI Linear Discriminant Analysis (LDA), and SST_W LDA forecasts. Two forms of the forecast are developed — a categorical forecast of below normal, normal or above normal streamflow, and an exceedance probability forecast. These two approaches are tested on data from eight Columbia River Basin streamflow stations covering the time period 1911 to 1992. It is encouraging that, at some stations, a three‐ to seven‐month lead time forecast of spring‐summer runoff has better skill than Climatology. This information may provide guidance to managers of water resource systems.

Select this Article		An Evaluation of the Impact of ENSO on the Discharges of the Salt River, Arizona Juan B. Valdés, Dara Entekhabi, Hyun‐Min Shin, and Huey‐Hong Hsieh ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)243 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The 1997–98 ENSO episode was one of the warmest on record and most closely monitored. The impact of the ENSO phenomena in the Southwest has been studied by several researchers. In this paper the impacts on the ENSO phenomena in the hydro‐climatology of the Salt River Basin is studied with particular emphasis in the latest episode.

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WATER DISTRIBUTION SYSTEMS ANALYSIS V: REAL TIME MONITORING & ANALYSIS OF WATER QUALITY

Select this Article		Optimizing Disinfection Strategy in the Network after a Dramatic Improvement of the Water Quality Leaving the Treatment Plant Ph. Piriou, A. Hemery, L. Kiene, M. R. Chevallier, and C. Anselme ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)244 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract To improve and make the finished water quality more reliable, the upgrading of the Vigneux sur Seine treatment plant was decided in 1996 and completed in 1997. Located in the Southeast of Paris, the Vigneux sur Seine treatment plant with a capacity of 55,000 m³/day provides potable water to at least 200,000 inhabitants. Measurement campaigns have already been performed at the treatment plant and on the network (10 sampling sites) before and after the implementation of CRISTAL® process to define the impact of this new treatment. They shows that CRISTAL® process leads to a decrease of more than 50% for TOC to reach values below 1.0 mg/l and BDOC around 0.2 mg/l in the network. TTHM decrease also by 10 (average value around 5 μg/l). A reduction of water chlorine demand by more than 2 is also noticed and leads to higher chlorine residuals in the network. The next step of this study is to adjust the existing chlorination strategy to this new water quality. Because bacterial regrowth phenomena in distribution systems are mainly under control of chlorine residuals and BDOC concentration, only water quality modeling can give us some indications on the combined effect of BDOC and chlorine residuals on water quality evolution in the network, by combining chlorine decay and bacterial regrowth (PICCOBIO) modeling. These models have been used in order to define a new chlorination strategy.

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SHORT‐TERM HYDROLOGICAL WATER DEM& FORECASTING & WATER OPERATIONS

Select this Article		Forecasting for Urban Water Demand Management Tracey C. Kenward, P. Eng. and Charles D. D. Howard, M.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)245 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The water supplies for major cities of the Pacific Northwest depend on surface runoff stored in reservoirs. The reservoir operation goal is to refill during the spring melt so that supplies will be available during the summer when precipitation is usually small and water demands are high. The possibility of water shortages during the late summer and fall is always a concern. The probability of water shortages depends on the probability distribution of inflows to the reservoirs, and the probability distribution of water consumption. In general, these distributions are not independent, nor are they highly correlated. Together they define the joint probability distribution function which is required to determine the reliability of the water supply system. The consumption can be managed through appeals to the customers as part of a water shortage response plan. This paper describes the methodology used in developing the water consumption forecast for the summer season in Vancouver and Victoria and the economic risk analysis used in the Seattle water supply expansion planning study.

Select this Article		Scheduling Hydro Generation — More Dollars or More Megawatt Hours: The TVA Story Arland W. Whitlock, P.E., M.ASCE, Clyde H. Rogers, and Christopher D. Ungate, P.E. ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)246 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The TVA hydro system consists of 29 TVA‐owned hydro plants and a pump‐storage plant with a total of 113 units and a nameplate capacity of 5,025 mw. In addition, TVA schedules the output of 4 ALCOA dams and 9 U.S. Army Corps of Engineers plants. Most of these plants had historically been scheduled for tomorrow based on yesterday's observed generation adjusted for unit availability as a surrogate for available capacity. A multi‐disciplinary team, with cumulative responsibility for multipurpose river operations, power scheduling and marketing, and hydro plant operations and maintenance was assembled within TVA to look at ways to increase the value of hydro generation. This paper describes HIGHER OUTPUT HYDRO (HOH) ‐ one of the 14 opportunities identified for design, development, and implementation to increase the net revenue of the TVA power system.

Select this Article		Modeling the Climatic Influences on Water Services Pricing Mahdi Al‐Sayed and A. Al‐Mershed ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)247 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The introduction of a new charging scheme and the imposition of stricter controls on water quality have apparently had effects on water use that have not considered in the past. In this pilot study of water consumption in metropolitan Kuwait, a quantitative assessment of the impact of the 1996 climatic conditions on water use is attempted using the demand management model PLAN. Three water consumption slices are identified to which the data are available namely: house‐hold, governmental, and agricultural. The variation in monthly in‐house water use is positively correlated with the temperature. The demand model PLAN indicated that the dry spell has a significant effect on water demand. The model also presented the relevant monthly water service charges per capita per consumption slice based on the modified PCI tariff system. The study suggests that, in order to conserve the fresh water resources under different climatic conditions, the price of water should properly be established through the interaction of the supply and demand while considering the effects of climatic changes.

Select this Article		A Decision Support System for Short Term Hydropower Scheduling and Reservoir Management in a Competitive Market Z. K. Shawwash, T. K. Siu, and S. O. Russell ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)248 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract This paper introduces a fast, user‐friendly decision support system that is currently used by the BC Hydro real‐time operations engineers for short‐term hydropower scheduling and reservoir management in a competitive energy market environment. The system consists of four major components: the Graphical User Interface (GUI), the Communication Protocols, the Simulation model, and the Optimization model. The GUI is a user‐friendly tool and a front end that allows the user to dynamically select a set of river systems and generating facilities to be included for simulation and optimization studies. It also allows the user to dynamically select one of several optimization objective functions, add or drop some of the model's constraints and specify some of its user input parameters and limits. The simulation model is coded in C language that accurately simulates the planned reservoir operations and calculates some of the optimization model input parameters and limits. The optimization model is formulated as a large‐scale linear programming algorithm and is solved using an advanced, commercially available algebraic modeling language and a linear programming package. The optimization model accurately represents the hydraulic and main environmental constraints of the modeled river systems. It also models the spot energy markets for Alberta and the Western U.S., and helps real‐time operations engineers in setting the optimal spot energy sale schedules that maximize the value of the B.C. Hydro resources. The system is linked to other operational tools, and is configured to launch the GUI from a Windows‐based personal computer client workstation, and to run the simulation and optimization models on a Windows NT server.

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FLOODPLAIN REGULATION & FLOOD WARNING RESPONSE PLANS

Select this Article		Regulatory Approval of Advanced Technology Floodplain Mapping Procedures in DuPage County, Illinois Robert Covey, Eric Loucks, and Jonathon Steffen ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)249 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract DuPage County is located approximately 30 miles west of downtown Chicago in northeastern Illinois. Although the 332 square mile county is the smallest of the “collar” counties surrounding Chicago, it is also the most populous. Rapid growth and development in the County during the 1960's and 1970's has put a tremendous strain on the natural stormwater drainage systems in DuPage County. This burden combined with poor stormwater management practices resulted in large areas of commercial and residential development within flood hazard areas. Frequent flooding throughout the 1970's and 1980's caused damages to many residential and commercial structures. A major flood, which occurred in August, 1987, caused more than $200 million in damages in DuPage County. In 1988, the County embarked on an ambitious program to address flooding problems. This program included the construction of more than $100 million in flood control projects, the strict enforcement of a comprehensive stormwater and floodplain ordinance, and the development of updated regulatory floodplain maps throughout the County. These initiatives became the responsibility of the newly formed Stormwater Management Division (SMD) of the DuPage County Department of Environmental Concerns. The SMD has managed the planning, design, and construction of many major flood control facilities over the last ten years. The SMD developed the Countywide Stormwater and Flood Plain Ordinance in 1991, and started enforcement of the Ordinance in February, 1992. Overall progress on revised floodplain maps has fallen short of expectations because of the reluctance of State and Federal agencies to approve a new floodplain mapping procedure. This paper presents the major elements of the DuPage County floodplain mapping techniques and the challenges that were encountered in gaining State and Federal approval of the advanced technology procedures. The purpose of this paper is twofold: first, it introduces the advanced technology procedures that are being utilized in DuPage County for floodplain mapping, and second, it presents the floodplain mapping case study of Ginger Creek.

Select this Article		Resolving Conflicts in Hydrologic Design Criteria: A Case Study in Maryland Michael A. Ports, F.ASCE ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)250 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Maryland law requires that all proposed changes to the course, current, or cross section of any non‐tidal waters of the State must first obtain a waterway construction permit from the State. Also by law, the waters of the State are defined to include the stream channel as well as the 100‐year floodplain. The Maryland State Highway Administration (SHA), therefore, is required to obtain waterway construction permits from the Maryland Department of the Environment (MDE)for every proposed bridge, culvert, or other roadway feature that encroaches into the 100‐year floodplain. As part of each permit application, the SHA must present the potential impacts from the proposed projects for the 2‐year, IO‐year, and 100‐year floods. In most, but not all, situations the hydrologic analysis must address ultimate development conditions in the affected watershed. For a variety of reasons, the MDE historically required, or at least preferred, the application of the TR‐20 watershed model to estimate peak flow rates under both existing and ultimate development conditions. Because sufficient data generally is not available to calibrate the TR‐20 model, significant time and resources frequently were expended by the two agencies merely to obtain agreement on the flow rates. The SHA felt that other hydrologic methods, such as gauging records, regression equations, or other models, should be considered where appropriate. In general, the SHA believed that the approved flow rates were too high and, thus, resulted in over‐designs. Significant conflict arose between the agencies.

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IMPACTS OF CLIMATE CHANGE ON WATER RESOURCES

Select this Article		Comparisons of Climate Elasticity of Streamflow in the United States Richard M. Vogel, M.ASCE, A. Sankarasubramanian, James F. Limbrunner, and Ian Wilson ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)251 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract The sensitivity of streamflow to climate is investigated by calculating precipitation and potential evapotranspiration elasticity of streamflow for 1,447 watersheds in the United States. A unique dataset of streamflow and climate time‐series is constructed which accounts for the complex spatial variations in climate across the U.S. Average annual values of streamflow, precipitation, temperature, and potential evapotransiration are used to estimate climate elasticity of the long‐term mean streamflow using a nonparametric (databased) approach, a regional regression approach and a water balance modeling approach. Comparisons are provided with nine previous climate change studies based on monthly water balance models and soil moisture accounting models Our results suggest that streamflow is more sensitive to changes in precipitation than to changes in potential evapotranspiration. Streamflow is particularly sensitive to both precipitation and potential evapotranspiration in the midwestern regions of the U.S. Difficulties with both the concept of elasticity and with its estimation are discussed and ongoing research is summarized. Climate elasticities derived from detailed monthly simulation experiments agree nicely with the simpler annual approaches outlined in this study.

Select this Article		Low‐Flow Frequency Exacerbation by Irrigation Withdrawals in the Agricultural Midwest under Various Climate Change Scenarios J. Wayland Eheart and Daniel W. Tornil ASCE Conf. Proc. doi:http://dx.doi.org/10.1061/40430(1999)252 Online Publication Date: 17 September 2004 Full Text: \| Download PDF
	+ -	Show Abstract Global climate change projections have created concern for the world's freshwater resources. Diminished precipitation, while directly decreasing the inflows to a region's surface water reserves, can also increase the surface water demand of irrigated agriculture. In the U.S. Midwest rainfall is normally abundant, droughts sporadic, and irrigation is not widespread. In such an area, even the threat of climate change may motivate farmers to invest in irrigation equipment to ensure they stay competitive in the market. Once such an investment is made, farmers will irrigate when increases in yield are only moderate, since the operating costs are low compared to capital costs. Riparian irrigators will likely withdraw directly from a watercourse, demand tending to be greatest when streamflows are lowest from late June through early August. This period includes the critical silking phase for corn. Moreover, the years with the greatest irrigation requirements will also be the years with the lowest streamflows. Since irrigation is likely to be concentrated at times when water resources are vulnerable, it is important to know how frequently that concentration will result in low‐flow events. Estimating that frequency is the focus of this paper, using Illinois as a typical example.