A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, nonpoint source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas.

Large Area Hydrologic Modeling and Assessment Part i: Model Development

Preface. 1. Tight relaxations for nonconvex optimization problems using the Reformulation-Linearization/Convexification Technique (RLT) H.D. Sherali. 2. Exact algorithms for global optimization of mixed-integer nonlinear programs M. Tawarmalani, N.V. Sahinidis. 3. Algorithms for global optimization and discrete problems based on methods for local optimization W. Murray, Kien-Ming Ng. 4. An introduction to dynamical search L. Pronzato, et al. 5. Two-phase methods for global optimization F. Schoen. 6. Simulated annealing algorithms for continuous global optimization M. Locatelli. 7. Stochastic Adaptive Search G.R. Wood, Z.B. Zabinsky. 8. Implementation of Stochastic Adaptive Search with Hit-and-Run as a generator Z.B. Zabinsky, G.R. Wood. 9. Genetic algorithms J.E. Smith. 10. Dataflow learning in coupled lattices: an application to artificial neural networks J.C. Principe, et al. 11. Taboo Search: an approach to the multiple-minima problem for continuous functions D. Cvijovic, J. Klinowski. 12. Recent advances in the direct methods of X-ray crystallography H.A. Hauptman. 13. Deformation methods of global optimization in chemistry and physics L. Piela. 14. Experimental analysis of algorithms C.C. McGeoch. 15. Global optimization: software, test problems, and applications J.D. Pinter.

/pdf/handbook-of-global-optimization-u51z5be3s6.pdf

Handbook of global optimization

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 the assistance of computer modeling tools to provide information for rational management and operational decisions. The purpose of this review is to assess the state-of-the-art in optimization of reservoir system management and operations and consider future directions for additional research and application. Optimization methods designed to prevail over the high-dimensional, dynamic, nonlinear, and stochastic characteristics of reservoir systems are scrutinized, as well as extensions into multiobjective optimization. Application of heuristic programming methods using evolutionary and genetic algorithms are described, along with application of neural networks and fuzzy rule-based systems for inferring reservoir system operating rules.

Optimal Operation of Multireservoir Systems: State-of-the-Art Review

Three criteria for evaluating the possible performance of water resource systems are discussed. These measures describe how likely a system is to fail (reliability), how quickly it recovers from failure (resiliency), and how severe the consequences of failure may be (vulnerability). These criteria can be used to assist in the evaluation and selection of alternative design and operating policies for a wide variety of water resource projects. The performance of a water supply reservoir with a variety of operating policies illustrates their use.

/pdf/reliability-resiliency-and-vulnerability-criteria-for-water-r6hc6h6q56.pdf

Reliability, resiliency, and vulnerability criteria for water resource system performance evaluation

The objective of this paper is to review the state-of-the-art of mathematical models developed for reservoir operations, including simulation. Algorithms and methods surveyed include linear programming (LP), dynamic programming (DP), nonliner programming (NLP), and simulation. A general overview is first presented. The historical development of each key model is critically reviewed. Conclusions and recommendations for future research are presented.

Reservoir Management and Operations Models: A State‐of‐the‐Art Review

Water resource systems planning and analysis

Multireservoir operating policies are usually defined by rules that specify either individual reservoir desired (target) storage volumes or desired (target) releases based on the time of year and the existing total storage volume in all reservoirs. This paper focuses on the use of genetic search algorithms to derive these multireservoir operating policies. The genetic algorithms use real-valued vectors containing information needed to define both system release and individual reservoir storage volume targets as functions of total storage in each of multiple within-year periods. Elitism, arithmetic crossover, mutation, and “en bloc” replacement are used in the algorithms to generate successive sets of possible operating policies. Each policy is then evaluated using simulation to compute a performance index for a given flow series. The better performing policies are then used as a basis for generating new sets of possible policies. The process of improved policy generation and evaluation is repeated until no further improvement in performance is obtained. The proposed algorithm is applied to example reservoir systems used for water supply and hydropower.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/96WR03745

Operating rules for multireservoir systems

Water distinguishes our planet compared to all the others we know about. While the global supply of available freshwater is more than adequate to meet all current and foreseeable water demands, its spatial and temporal distributions are not. There are many regions where our freshwater resources are inadequate to meet domestic, economic development and environmental needs. In such regions, the lack of adequate clean water to meet human drinking water and sanitation needs is indeed a constraint on human health and productivity and hence on economic development as well as on the maintenance of a clean environment and healthy ecosystems. All of us involved in research must find ways to remove these constraints. We face multiple challenges in doing that, especially given a changing and uncertain future climate, and a rapidly growing population that is driving increased social and economic development, globalization, and urbanization. How best to meet these challenges requires research in all aspects of water management. Since 1965, the journal Water Resources Research has played an important role in reporting and disseminating current research related to managing the quantity and quality and cost of this resource. This paper identifies the issues facing water managers today and future research needed to better inform those who strive to create a more sustainable and desirable future.

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1002/2014WR016869

Water management: Current and future challenges and research directions

An inexact two-stage stochastic programming (ITSP) model is proposed for water resources management under uncertainty. The model is a hybrid of inexact optimization and two-stage stochastic programming. It can reflect not only uncertainties expressed as probability distributions but also those being available as intervals. The solution meth od for ITSP is computationally effective, which makes it applicable to practical problems. The ITSP is applied to a hypothetical case study of water resources system operation. The results indicate that reasonable solutions have been obtained. They are further analyzed and interpreted for generating decision alternatives and identifying significant factors that affect the system's performance. The information obtained through these post-optimality analyses can provide useful decision support for water managers.

Daniel P. Loucks

Papers

Reliability, resiliency, and vulnerability criteria for water resource system performance evaluation

Water resource systems planning and analysis

Operating rules for multireservoir systems

Water management: Current and future challenges and research directions

An inexact two-stage stochastic programming model for water resources management under uncertainty