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91.
Taiye B. Sangoyomi Benjamin L. Harding 《Journal of the American Water Resources Association》1995,31(5):925-938
ABSTRACT: We evaluated the effects of institutional responses developed for coping with a severe sustained drought (SSD) in the Colorado River Basin on selected system variables using a SSD inflow hydrology derived from the drought which occurred in the Colorado River basin from 1579–1616. Institutional responses considered are reverse equalization, salinity reduction, minimum flow requirements, and temporary suspension of the delivery obligation of the Colorado River Compact. Selected system variables (reservoir contents, streamflows, consumptive uses, salinity, and power generation) from scenarios incorporating the drought-coping responses were compared to those from Baseline conditions using the current operating criteria. The coping responses successfully mitigated some impacts of the SSD on consumptive uses in the Upper Basin with only slight impacts on consumptive uses in the Lower Basin, and successfully maintained specified minimum streamflows throughout the drought with no apparent effect on consumptive uses. The impacts of the coping responses on other system variables were not as clear cut. We also assessed the effects of the drought-coping responses to normal and wet hydrologic conditions to determine if they were overly conservative. The results show that the rules would have inconsequential effects on the system during normal and wet years. 相似文献
92.
Assessing national sustainable development strategies: Strengthening the links to operational policy
At the Earth Summit in Rio de Janeiro in 1992, it was agreed that all countries should develop a national sustainable develop‐ment strategy (NSDS) as a key component of implementing the goals of Agenda 21. Progress has been limited. Few countries have established a formal strategy, and many of the strategies that exist have been only partially implemented. This article proposes an approach that addresses the need to improve existing strategic planning mechanisms. The approach is based on a periodic assessment of existing systems, to evaluate the extent to which they incorporate NSDS principles, and identify areas to be strengthened. The article describes an assessment methodology, presents examples of its use, and discusses ways in which current approaches to NSDS may be complemented by continual review and improvement of existing planning processes. 相似文献
93.
Jessica Sargent‐Michaud Kevin J. Boyle Andrew E. Smith 《Journal of the American Water Resources Association》2006,42(5):1237-1245
ABSTRACT: This study was undertaken to investigate the cost effectiveness of selected arsenic avoidance methods. Annual costs of reverse osmosis (RO), activated alumina (AA), bottled water, and rented and purchased water coolers for various household sizes in Maine were compared. Relative ranking of systems shows that RO ($411 annually) is the most cost effective, followed by AA ($518) and one‐gallon jugs of water ($321 to $1,285), respectively, for households larger than one person. One‐gallon jugs ($321) followed by 2.5‐gallon jugs ($358) of water were found to be the most cost effective for households of one person or for households with arsenic III concentrations of 0.02 to 0.06 mg/L and arsenic V concentrations of 0.08 to 1.0 mg/L. Point‐of‐entry systems and water coolers were not found to be cost effective under any of the study's conditions. The research reported here will help states make more definitive treatment recommendations to households regarding the cost effectiveness of alternative treatment systems to reduce arsenic concentrations below 0.01 mg/L. While arsenic removal technologies are improving, which enhances removal rates and reduces costs, the major insights from this analysis appear to be reinforced by technological improvements. 相似文献
94.
Donald M. Anderson Mark W. Rodney 《Journal of the American Water Resources Association》2006,42(5):1391-1403
ABSTRACT: Efforts are under way to recover habitat for several threatened and endangered species in and along the Platte River in central Nebraska. A proposed recovery program for these species requires a means of characterizing “wet” versus “normal” versus “dry” hydrologic conditions in order to set corresponding Platte River instream flow targets. Methods of characterizing hydrologic conditions in real time were investigated for this purpose. Initially, 10 watershed variables were identified as potentially valuable indicators of hydrologic conditions. Ultimately, six multiple linear regression equations were developed for six periods of the year using a subset of these variables expressed as frequencies of nonexceedence. The adequacy of these equations for characterizing conditions was assessed by evaluating their historic correlation to subsequent flow in the central Platte River (1947–1994). These equations explained 54 to 82 percent of variability in the observed flow exceedences in the validation datasets, depending upon the period of year evaluated. These equations will provide initial criteria for setting applicable flow targets to determine, in real time, whether water regulation projects associated with the species recovery effort can divert or store flows without conflicting with recovery objectives. 相似文献
95.
江苏省城市防汛决策支持系统研究 总被引:2,自引:2,他引:2
在分析江苏省城市防汛问题的基础上,设计了其防汛决策支持系统;根据江苏省城市洪涝灾情特点研建和选用了适宜的数学模型,该模型可以迅速、可靠和正确地模拟城市雨情、水情、灾情的发展过程和可能后果,为城市防汛决策提供多层次的信息服务和多种支持手段。 相似文献
96.
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98.
Vinod Lohani David F. Kibler Jeffery Chanat 《Journal of the American Water Resources Association》2002,38(2):439-452
ABSTRACT: This paper describes the integration of a comprehensive hydrological model known as the Hydrological Simulation Program Fortran (HSPF) into a problem solving environment (PSE) for watershed management. The original PSE concept was a structure providing web‐based access to a suite of models, including HSPF and other models of in‐stream hydrodynamics, biological impacts and economic effects, for the watershed‐wide assessment of alternative land use scenarios. The present paper describes only the HSPF integration into the PSE program. Example applications to the 148 square kilometer (57 square mile) Back Creek subwatershed in the upper Roanoke River system (1,479 square kilometers or 571 square miles) in southwest Virginia are used to illustrate important concepts and linkages between land development and hydrological change using hypothetical' what if'scenarios. The features of HSPF and its limitations in this context are discussed. The paper as such is a proof‐of‐concept paper and not a completion report. It is intended to describe the PSE tool building process rather than analysis of the many possible simulation outcomes. However, the dominance of raw imperviousness as a contributor to hydrograph response is apparent in all the PSE simulations described in this paper. 相似文献
99.
Mark R. S. Johannes Kim D. Hyatt Josie K. Cleland Leila Hanslit Margot M. Stockwell 《Journal of the American Water Resources Association》2002,38(2):555-562
ABSTRACT: Watershed stewardship activities throughout North America have evolved into a process that requires more involvement in planning and decision making by community stakeholders. Active involvement of all stakeholders in the process of watershed stewardship is dependent on effective exchange of information among participants, and active involvement of a wide range of stakeholders from “communities of place” as well as those from “communities of interest.” We developed a map‐based stream narrative tool as a means to: (a) assemble a wealth of incompletely documented, “traditional” ecological or natural history observations for rivers or streams; and (b) promote a higher level of active involvement by community stakeholders in contributing to information‐based, watershed management. Creation of stream narratives is intended for use as a tool to actively engage local stakeholders in the development of a more comprehensive information system to improve management for multiple stewardship objectives in watersheds. Completion of map‐based stream narrative atlases provides a valuable supplement to other independent efforts to assemble observations and knowledge about land‐based natural resources covering entire watersheds. We are confident that completion of stream narrative projects will make a valuable addition to the information and decision making tools that are currently available to the public and resource agencies interested in advancing the cause of community‐based approaches to watershed and ecosystem management. 相似文献
100.
Robin S. Gregory Ralph L. Keeney 《Journal of the American Water Resources Association》2002,38(6):1601-1612
ABSTRACT: This paper outlines a sound, practical approach for making more informed decisions about environmental policy choices. It emphasizes the importance of using a structured decision process to specify and organize values, use these values to create alternatives, and assess tradeoffs to help achieve a desired balance across key objectives. Although these decision making steps are based on common sense, they are often neglected or poorly carried out as part of the complex evaluations of natural resource options. We discuss several reasons for this frequent neglect of decision making principles and provide examples from recent water use planning projects to demonstrate some of the benefits of using a structured, decision focused approach: new and better solutions, increased and more productive participation by stakeholders, and greater defensibility and acceptance of the resource management evaluation process and its conclusions. 相似文献