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Publications
Publications (109)
Tributary stream systems provide an important source of water for sustaining adjacent irrigated agricultural enterprises. Unfortunately, irrigation withdrawals, depending on the timing and amounts, can have substantial negative impacts on critical aquatic ecosystems in the tributaries. Current regulatory trends in many regions point to increased re...
In Colorado's Lower Arkansas River Basin (LARB), inefficient irrigation and canal seepage contribute to salinization and waterlogging of irrigated lands and to stream-aquifer pollution. The geographic information system (GIS)-based river basin management model River GeoDSS is applied to further explore best management practices (BMPs) earlier deter...
Inefficient irrigation practices in the alluvial Lower Arkansas River Basin (LARB) of Colorado are contributing to salinization, waterlogging, reduced crop yields, and harmful concentrations of pollutants in the stream-aquifer system. Intensive data collection and modeling efforts in the LARB over the past 20 years have resulted in development of t...
Purpose
– The purpose of this paper is to present a real world application of an innovative hybrid system reliability optimization algorithm combining Tabu search with an evolutionary algorithm (TSEA). This algorithm combines Tabu search and Genetic algorithm to provide a more efficient search method.
Design/methodology/approach
– The new algorith...
River management involves satisfying societal preferences alongside environmental needs for a healthy river ecosystem. Environmental flows is a discipline that aims to define streamflow requirements that achieve desired social and ecological conditions in rivers.
The ecological limits of hydrologic alteration (ELOHA) framework takes a regional appr...
There has long existed a dichotomy in the field of water resources systems engineering between simulation and optimization modeling, with each approach having its own advantages and disadvantages. Simulation models provide a means of accurately representing the complex physiochemical, socioeconomic, and legal-administrative behavior of complex wate...
Applications of environmental models may provide imperative information to enable informed decision-making of river management actions, which are often made in the face of high system complexity and uncertainty. We applied Hydrologic Engineering Centers River Analysis System(HEC-RAS) and Curvilinear Hydrodynamics Three-Dimensional (CH3D) models to...
The long-term sustainability of irrigated agriculture is contingent on application of cost-effective water conservation measures and improved management in the face of intense competition for limited freshwater resources from municipal, industrial, and environmental/ecological interests. A geographic information system (GIS)-based decision support...
A generalized software package is presented for developing an
intelligent agent for stochastic optimization of complex river-reservoir
system management and operations. Reinforcement learning is an approach
to artificial intelligence for developing a decision-making agent that
learns the best operational policies without the need for explicit
proba...
Successful implementation of integrated water resources planning and management (IWRM) requires delineation of regions that are relatively homogeneous with respect to multiple criteria, including hydrographic, physical-environmental, socioeconomic, and political-administrative aspects. The water resources planning and management (WARPLAM) DSS is pr...
Attachment of stormwater treatment areas (STAs) or constructed wetlands to stormwater retention reservoirs can achieve substantial reductions in pollutant loadings if properly operated and maintained. Besides water quality improvement, optimally operated reservoir-assisted STAs provide support for ecosystem remediation, flood control, and supplemen...
Artificial neural networks (ANNs) are applied to efficient modeling of stream-aquifer responses in an intensively irrigated river basin under a variety of water management alternatives for improving irrigation efficiency, reducing soil water salinity, increasing crop yields, controlling nonbeneficial consumptive use, and decreasing salt loadings to...
The Lower Arkansas River (LAR) Basin in Colorado, like many intensively irrigated river basins in the Western United States, faces a variety of problems associated with inefficient irrigation, seepage from earthen canals, and inadequate drainage facilities. Upward flows from high water tables have salinized and waterlogged agricultural soils of the...
Real-time monitoring, databases, optimization models and visualization tools have been integrated into a Decision Support System (DSS) for optimal water resources management of two water supply reservoirs, the Daechung Reservoir and the Yongdam Reservoir of the Geum River basin, Daejeon, Korea. The KModSim as a DSS has been designed to provide info...
Research conducted at the field and regional scales in the Lower Arkansas River (LAR) Valley of Colorado has identified water management alternatives with potential for enhancing agroenvironmental conditions in the basin by reducing waterlogging and soil salinity, salt loadings to the river, and nonbeneficial evapotranspiration in the irrigated str...
Water resources planning and management tools have been moving away from a top down (command and control) approach to a bottom up (grass-roots) approach - which emphasizes the involvement of stakeholders, not only specialists, in all stages of planning - from the identification of problems and issues, the selection of potential solutions to project...
Although several variants of stochastic dynamic programming have been applied to optimal operation of multireservoir systems, they have been plagued by a high-dimensional state space and the inability to accurately incorporate the stochastic environment as characterized by temporally and spatially correlated hydrologic inflows. Reinforcement learni...
Attempts at implementing real-time control systems as a cost-effective means of minimizing the pollution impacts of untreated combined sewer overflows have largely been unsustained due to the complexity of the real-time control problem. Optimal real-time regulation of flows and in-line storage in combined sewer systems is challenging due to the nee...
The MODSIM 8.0 decision support system (DSS) for integrated river basin management (IRBM) has been adapted from a prior appropriation rights-based system to one found in Korea and in much of Asia where water deficits are shared among water use sectors, taking into account priorities established by water policy and institutional frameworks. The Kore...
ABSTRACT This paper briefly reviews the problem of ground water degradation from irrigation and present approaches to controlling ground water quality. As an alternative to these approaches, a management scheme called the Accelerated Salt TRANsport (ASTRAN) method is proposed as being a feasible solution to the problem of salt build-up in irrigated...
A surrrogate-prarmeter approach to modeling groundwater basins is presented, which has the following advantages over current simulation-type methods: (i) conducivness to modeling nonhomogeneous and nonisotropic basins; (ii) there is no need to guess boundary conditions if accurate information is not available; (iii) the model is amenable to systema...
There is considerable misconception about the dangers of opening to a recreating public in great need of additional open areas. A systematic procedure for identifying the factors essential to the selectio, planning, and management of reservoirs for recreation is described. A detailed case study conducted by an interdisciplinary project team is pres...
Development of optimal operational policies for large-scale reservoir systems is often complicated by a multiplicity of conflicting project uses and purposes. A wide range of multiobjective optimization methods are available for appraising tradeoffs between conificting objectives. The purpose of this study is to provide guidance as to those methods...
Many coastal ecosystems have been adversely impacted by increased storm-water drainage due to expanding urbanization. The ecosystem of the St. Lucie Estuary (SLE), located on the east coast of south Florida, has been greatly influenced by development of an
intricate network of storm-water drainage canals in the tributary watershed. A suite of model...
Many river systems include natural and manmade backwater areas providing habitat for a diverse community of aquatic and aviary species, including several listed as endangered by the U.S. Fish and Wildlife Service. Concern has been raised over ecological impacts of river operations on these species and their habitat in these backwater areas. A metho...
MODSIM 8.0 is a generic river basin management decision support system for analysis of long term planning, medium term management, and short term operations on desktop computers operating under MS Windows 2000/XP. MODSIM is free from expensive licenses for proprietary software since all components are developed from native code or shareware under t...
This chapter reports the main results of a workshop held in Boulder, Colorado, on June 21-22, 1999. The workshop dealt with the development potential for water-resources modeling based on climate and hydrology. The workshop participants, who represented a range of expertise in the field of water-resource s management and water-resources modeling, w...
A joint international collaboration between the Korea Water Resources Corporation (KOWACO) and Colorado State University has resulted in development of a decision support system (DSS) for daily operations in the Geum River Basin, Korea. The DSS is a customized version of the MODSIM Generalized River Basin Network Flow Model, which has been adapted...
A comprehensive decision support system (DSS) is presented that combines the MODSIM river basin network flow model with geographic information systems (GIS) and an artificial neural network (ANN) for basin-wide water management and salinity control under appropriative water rights and other legal, institutional, and administrative structures. The M...
With construction of new large-scale water storage projects on the wane in the U.S. and other developed countries, attention must focus on improving the operational effectiveness and efficiency of existing reservoir systems for maximizing the beneficial uses of these projects. Optimal coordination of the many facets of reservoir systems requires th...
The hydropower unit commitment and loading problem represents a complex decision-making process involving the integrated hourly scheduling of generators in a multiproject hydropower system. Optimal scheduling maximizes basinwide operating efficiency while satisfying power load demands, water demands, reliability constraints, operational restriction...
A tool is presented for modeling complex stream-aquifer interactions by integrating an artificial neural network (ANN) with a geographic information system (GIS) and a numerical groundwater model. The proposed methodology allows development of dynamic, spatially dependent relationships between measurable aquifer stresses and river return flow. A we...
The lower Colorado River below Parker Dam is highly influenced by the needs of mankind, with several dams and diversion structures controlling flow for a variety of purposes. Along this reach of river, many natural and manmade backwater areas provide habitat for a diverse community of aquatic and aviary species. The environmental, ecological, engin...
A prototype spatial decision support system (SDSS) is presented for integrated, real-time river basin flood control in a multipurpose, multireservoir system. The SDSS integrates a geographic information system with a database management subsystem, a real-time meteorological and hydrological data monitoring system, a model-base subsystem for simulat...
A prototype spatial decision support system (SDSS) is presented for integrated, real-time river basin flood control in a multipurpose, multireservoir system. The SDSS integrates a geographic information system with a database management subsystem, a real-time meteorological and hydrological data monitoring system, a model-base subsystem for system...
Saline high water tables pose a growing threat to the world's productive irrigated land. Much of this land lies along and alluvial plains, where solutions must now be developed in the context of changing constraints on river management. Findings are presented from the preliminary phase of a project aimed at developing, through well-conceived data c...
Desalination of sea and brackish water is gaining interest as a viable water source in several and regions of the world where limited freshwater resources are under stress from increasing demands and deteriorating water quality. Although a few large desalination plants exist and are planned for future implementation, most desalinization facilities...
The MODSIM river basin network flow model is extended to directly incorporate constraints on concentrations of conservative water quality constituents. The extended model MODSIMQ is linked with the U.S. Environmental Protection Agency's QUAL2E streamflow water quality model and a model for estimating quality of irrigation return flows. An iterative...
An optimization model has been developed toaid decision making in real time fordeficit irrigation when conflict betweenwater supply and demand arises in amultiple crop irrigation scheme. The resultis the optimal allocation of short-termsupply of irrigation water. Theoptimization model is based on DynamicProgramming. In the optimization model, thesh...
A vast array of techniques have been developed and applied to optimal operation of large-scale multireservoir systems. Researchers
continue to be challenged by the highly complex, stochastic, nonlinear, and high dimensional nature of this dynamic optimization
problem. An optimal control model is presented which incorporates chance-constraints on s...
A Decision Support System (DSS) for optimal operation of multireservoir systems employs the powerful graphical user interface for the MODSIM river basin network flow model in creating applications for the CSUDP dynamic programming package. The DSS provides capability for graphical construction of multireservoir system networks and object oriented d...
The integration of surface water quantity and quality objectives within the framework of a decision-support tool is presented in an application to the 12,400-km2 Piracicaba River Basin in the state of Sao Paulo, Brazil. Emphasis is given to simulation-based assessment of strategic planning alternatives through the combined use of water allocation (...
Handling a community's waste streams can be one of the greatest challenges faced urban planners and engineers. Many urban areas are finding geographic information systems (GIS) to be an important tool to reduce costs of installation, expansion, and maintenance of stormwater and waste management systems. This chapter is divided into two sections. Th...
As with all dynamic programming formulations, differential dynamic
programming (DDP) successfully exploits the sequential decision structure
of multi-reservoir optimization problems, overcomes difficulties
with the nonconvexity of energy production functions for hydropower
systems, and provides optimal feedback release policies. DDP is particularly...
The quality of impounded waters often degrades over time because of
thermal stratification, sediment oxygen demands, and accumulation of
pollutants. Consequently, reservoir releases impact water quality in
tailwaters, channels, and other downstream water bodies. Low dissolved
oxygen (DO) concentrations in the Cumberland River below Old Hickory dam...
A decision support system (DSS) is presented for conjunctive management of surface water and ground water under prior appropriation. The DSS is constructed around the generalized river basin network flow model MODSIM, providing an open architecture allowing access to input and output database and modification and verification at all levels of the m...
The indexed sequential hydrologic modeling (ISM) methodology is utilized by the Western Area Power Administration as the basis for risk-based estimation of project-dependable hydropower capacity for several federally owned/operated projects. ISM is a technique based on synthetic generation of a series of overlapping short-term inflow sequences obta...
Detention basins are the most popular structural measure for urban food control and have proven effective for both water quantity and quality management. Integrated, watershed-level planning of the layour and sizing of detention systems is essential because localized solutions may actually aggravate the negative impacts of urban drainage. Successiv...
The predictive canal operation method (PCOM) provides optimal real-time control of irrigation canals with incorporation of current and forecasted demands. PCOM utilizes an efficient, nonlinear, optimal control algorithm interacting with a fully dynamic, unsteady-flow hydraulic model. Optimal predictive controls are determined for all check structur...
Many powerful optimal design models have been developed for municipal water-distribution networks but few are in practical use since they are difficult for water engineers to understand and require an extensive data base for implementation. To aid in technology transfer of water-distribution system optimizers, a prototype decision support system WA...
A methodology is presented for water quantity and quality assessment for wetland development which enables planners to evaluate the results of restoring and managing a large wetland complex based on a set of criteria developed under multi-disciplinary guidelines. The methodology includes addressing temporal and spatial variability of climatic data...
A methodology is presented for water quantity and quality assessment for wetland development which enables planners to evaluate the results of restoring and managing a large wetland complex based on a set of criteria developed under multi-disciplinary guidelines. The methodology includes addressing temporal and spatial variability of climatic data...
Increasing use of distributed, physically based urban storm water management models requires urban water managers to acquire, maintain, and utilize the extensive, spatially referenced data bases necessary to support these efforts. Geographic information systems (GIS) are ideally suited to preparing, storing, updating, analyzing, and displaying thes...
Historically, there has existed a dichotomy in relation to the use of descriptive models (i.e. simulation) and prescriptive models (i.e. optimization) in river basin management. This is unfortunate, since there are unique advantages with each modelling approach which can be greatly enhanced through their joint usage. Descriptive models allow accura...
Computerized decision support systems can provide the foundation of maximizing the productivity, cost-effectiveness and reliability of complex water resource systems. The three fundamental subsystems of a decision support system (DSS) are: (i) dialogue subsystem, (ii) data subsystem, and (iii) models subsystem. The microcomputer revolution and the...
The U.S. Bureau of Reclamation has the responsibility for developing implementation strategies for salinity control projects in the Colorado River Basin. Determining when and which projects should be built depends primarily upon the planning and construction funds available at various times during the program period and other considerations. The pa...
A comprehensive scheduling algorithm is presented for optimally integrating irrigation and pump operational decisions in center-pivot sprinkler systems. Dynamic programming successive approximations (DPSA) is applied to optimal timing of center pivot operations which minimizes energy costs subject to maintaining required system pressures and favora...
Indexed sequential modeling (ISM) has been proposed by the Western Area Power Administration as an alternative approach to developing firm marketable capacity, i.e., project-dependable hydropower capacity (PDC), in contrast with the usual approach of basing PDC on the most adverse period of record. ISM allows a probabilistic analysis of hydropower...
Large-scale water resource projects must be operated and maintained so that the benefits for which they were built actually occur. The key to substantial improvement in project performance is in operating the various project components in a comprehensive, integrated fashion. Optimal integration of the system's many facets and analysis of tradeoffs...
A water supply network optimization model called MODSIM3 is presented as a decision-support tool for aiding city staff in determining how best to utilize and exchange existing and potential water supplies with other users in a river basin. The model is applied to the City of Fort Collins, Colorado, water supply system as a means of determining opti...
A generalized network flow model has been developed to simulate the allocation of additional water supplies in a river basin with observance of the prior appropriation doctrine of water rights and other legal requirements such as interstate compact agreements. The computer model, called MODSIMR, is capable of simulating complex river basin morpholo...
A compendium of several important articles on the application of computerized decision support systems (DSS) in water resources management is presented. The articles cover software development, hardware selection, data acquisition and control, successes, pitfalls, and both a small and large scale. DSSs are described for hydropower system operation,...
A methodology is developed for estimating and forecasting soil water depletion and crop evapotranspiration, with explicit consideration of modeling errors and stochastic inputs. The water balance of an irrigated field and a time series model for reference crop evapotranspiration are formulated in state-space form, with soil moisture depletion and r...
A dynamic programming model is formulated for determining surface
irrigation schedules over the short term that minimize irrigation labor
costs while meeting crop requirements under a limited water supply. This
is a relevant problem for a large number of farm operations on the High
Plains served by wells tapping the Ogallala Aquifer. The model is
c...
A methodology employing dynamic programming is presented for integrating the optimal design of water supply, treatment, and conveyance systems, where demands for water may vary over a year. The analysis begins with the water conveyance system so as to determine overall monthly water allocations for various possible discrete levels of annual firm yi...
Bibliography: p. 122-125. CCRICWRI100147CRPT CSU Centers and Research Institutes Data Dictionary
A mixed-integer optimization model is developed which provides scheduling guidelines for surface irrigation systems over one to two week forecast periods. The model is linked with USDA-ARS Irrigation Scheduling Program for predicting evapotranspiration and soil moisture depletions. The solution algorithm utilizes a branch and bound technique which...
In developing a plan to effectively manage a complex water resource system, some form of water supply forecasting is required. In areas with a large spring snowmelt runoff, a total seasonal forecast of streamflow is often available from snow surveys as input to some type of multiple linear regression model. These seasonal estimates provide a basis...
A methodology combining simulation and optimization techniques is
presented for determining optimal operational guidelines for selective
withdrawal structures to meet downstream water temperature objectives.
The goal is to develop operating rules that take into account
anticipation of future critical temperature conditions that could occur.
A one-d...
Real-time, short-term rainfall forecasting is gaining recognition as a
valuable input to more effective performance of a variety of urban water
management activities, including controlling the incidence of untreated
combined sewer overflows. An important question is, What levels of
forecast error can be tolerated before it is better to abandon adap...
River basin computer simulation studies often do not properly include the complex legal and institutional factors governing water allocation. These factors include formal water rights and informal borrowing agreements among the basin water users. An attempt has been made in this study to show that such factors can be included. We also show that an...
The impacts of additional new demands for water on a complex multipurpose, multireservoir river basin system such as the Cache la Poudre, in Colorado are pervasive and difficult to analyze without the use of computer models. This paper reports on a study that analyzes the impacts of a new demand in the basin for a cooling pond water supply for oper...
A particularly challenging problem is the development of appropriate optimal control logic for adjustable valves, gates and regulators that includes consideration of unsteady sewer flows and backwater effects. Dynamic programming appears to be a particularly attractive optimization approach, but the multidimensional character of the control problem...
A new salinity management strategy for irrigated stream-aquifer systems, called the accelerated salt transport (astran) method, is described. It is based on the idea that the generally slow salt transport naturally occurring in the saturated zone of a groundwater basin can be augmented by using well pumpage on irrigated lands downstream of the well...
The accelerated salt transport (astran) method for managing salinity in an irrigated stream-aquifer system is applied to the lower San Luis Rey River basin in southern California. The hierarchical management algorithm developed in Part I is applied for optimally implementing astran over the basin. Three subbasins are included in the study; Pauma, P...
The report describes the development of a simulation model for water planning or management in a Front Range River basin or sub-basin. The application of the model is illustrated by two cases. Cooling water demands for the Rawhide Power Plant in Larimer County are proposed to be met with reusable foreign water from Fort Collins' sewer effluent. The...
Bibliography: p. 62-63. CCRICWRI100111CRPT CSU Centers and Research Institutes Data Dictionary
4 number of United States cities have applied, or plan to study, automatic computer control technology to urban stormwater management. Several control strategies are compared, from simple set point or reactive control, to stochastic optimal control with full storm forecasting carried out adaptively in real-time. A simulated real-time experiment was...
One of the pressing problems facing the irrigation intensive areas of
the world is the increasing salinity of groundwater. A cost-effective
salinity management technique, called the accelerated salt transport
(Astran) method, has been developed which may be feasible for many
stream aquifer systems. The basic idea is to encourage application of
pump...
Scheduling programs that recommend the date and volume of water to apply to each field are developed and used for assisting management. The new management program optimizes the on-farm allocation of water within the limits of available water and labor as demonstrated on one farm with 40 fields.
Bibliography: p. 141-145. CCRICWRI100110CRPT CSU Centers and Research Institutes Data Dictionary
Simulation and optimization techniques were employed in developing strategies for the operation of detention reservoirs for the control of combined sewer overflows. A single subbasin reservoir system in the San Francisco Plan for Wastewater Management was used as a case study. A simulation model was constructed and used in conjunction with both art...
Many geohydrologists believe that the step-drawdown test is useful in determining many important characteristics of a well, whereas others altogether question its utility. In addition to this controversy, its application is hindered because the graphical analysis of data is unwieldy. A computer code is presented for step-drawdown test analysis whic...
The pollution of receiving waters by overflows from combined sewers is a national problem of serious concern. A recent viable solution strategy for the problem involves the development of automatic control systems as an alternative to more expensive sewer separation or large-scale treatment projects. Development of the control logic is difficult, d...
There is a critical need for the development and implementation of control strategies for minimizing receiving water pollution caused by overflows from urban combined sewer systems. Automation and control of such systems has risen as a viable approach to this problem. Control is carried out through regulation of ambient and/or auxiliary storage in...
Deficiency of data is a serious obstacle to river basin management in developing countries. A lumped, nonlinear, seasonally time variant rainfall-runoff model is applied to the problem of augmenting limited monthly runoff data for the Todzie River basin, Ghana. When the trade-off between model realism (and therefore complexity) and its practical us...
A MATHEMATICAL MODEL IS PRESENTED AS A TOOL IN FACILITATING THE ANALYSIS AND OPTIMISATION OF THE CONJUNCTIVE USE OF SURFACE AND GROUND WATER RESOURCES OF A SUBSYSTEM OF THE INDUS BASIN IRRIGATION SYSTEM IN PAKISTAN.THE OBJECTIVE OF THE STUDY IS TO DETERMINE THE SIZE OF THE CANAL SYSTEM, THE SURFACE RESERVOIR, AND THE GROUND WATER PUMPING FACILITIES...
The MODSIM river basin management model has been extended to GEO-MODSIM for integration with GIS for spatial data base management, analysis, and display. GEO-MODSIM is a custom ArcMap extension that provides the foundation for integrated river basin management. Numerous geodatabase layers are loaded and processed in GEO-MODSIM, including topography...
A methodology is presented for modeling stream-aquifer interactions at the river basin scale that integrates an artificial neural network (ANN), a geographical information system (GIS), and the MODSIM generalized river basin network flow model. The methodology allows development of dynamic, spatially dependent relationships between measurable aquif...
The lack of uniform and integrated water resources regions is a critical issue, especially in transboundary water regions and federative countries. Overlaying levels of planning and man-agement, as a result of uncoordinated water resources regions, hamper Integrated Water Resources Management. In order to harmonize multiple objectives and better re...