A SCREENING MODEL FOR WATER RESOURCES PLANNING1

ABSTRACT: Techniques of optimization and simulation are merged to select the most efficient arrangement of components for regional water resources development and management. Application is made to the Elkhorn River Basin in Nebraska. The Basin extends over 7,000 square miles and includes 184 proposed reservoirs. Structure sizes, locations and operating policies are selected for optimal plans based on economic efficiency and regional development. Results indicate that substantial savings in time and costs over conventional planning techniques are effected. Agreement between model output and agency design values was noted.     

A hierarchical framework for stream habitat classification: Viewing streams in a watershed context

Environmental Management - Classification of streams and stream habitats is useful for research involving establishment of monitoring stations, determination of local impacts of land-use practices,...     

ADDRESSING SOCIAL AND ENVIRONMENTAL ISSUES IN WATER RESOURCES PLANNING AND MANAGEMENT1

Understanding social goals and objectives and incorporating them in water resources planning, management, education and engineering processes is the key to solving many current and emerging water resources problems. Water resources professionals must turn more of their attention to this issue. Various avenues are open for their involvement. They include lobbying, participating in government, education and research, publishing, establishing institutions, interacting with the public and analyzing existing systems.     

National water policy: The need for institutional reform

The water policy of the United States of America has evolved over many years from an uncoordinated and often narrowly focused collection of legislative and administrative actions. Unfortunately, these elements are frequently in conflict, with the result that efforts to assure adequate water supplies for the future are ineffective. Water policy reform is urgently needed to preclude a major scale water crisis.The views expressed are those of the author and not necessarily those of the Library of Congress or any member of Congress.     

Applying the Protective Role of Condensed Tannins to Acrylic-based Surface Coatings Exposed to Accelerated Weathering

Condensed tannins, extractable from tree bark have been assessed as functional additives to provide a protective role to acrylic-based coating resins. In addition to retaining high antioxidant capacity, the UV absorption properties of native and chemically modified tannins were found to be variously impacted by pH and degree of esterification or etherification. When added to acrylic-based coatings, these tannins were found to contribute colour to a white-base, but only small perceptive differences were found for clear coated wood using typical additive loadings of 0.1–0.4%. Integration of tannins in native or modified form to do not inhibit the cure of acrylic coatings or found to leach from cured coating films. Accelerated weathering was used to evaluate the photo-stability of tannin-modified acrylic and styrene-acrylic coatings. Native and modified tannins with maleate or methylcarboxylate groups retaining high antioxidant activity were associated with significantly greater coating longevity and performance than use of a synthetic photostabiliser. Moreover, esterified condensed tannins with a high degree of substitution also outperformed synthetic additives indicating the inherent UV absorption potential of these materials also contributed this efficacy within the acrylic and styrene-acrylic coating systems.     

Incorporating cleaner production analysis into environmental impact assessment in china

An environmental impact assessment (EIA) system was established in 1979 in China. Although EIA was designed as a tool for pollution prevention, in practice it has been based on end-of-pipe (EOP) treatment control since it was first introduced. This approach has ensured an overwhelming focus by enterprises on the use of EOP treatment, rather than pollution prevention, to meet environmental standards, and it has produced a low rate of operation for EOP facilities. The low operation rate for EOP facilities can be traced to the traditional EIA system: it leads project proponents to develop large EOP treatment facilities, but once the main production lines are put into operation, proponents rarely have sufficient funds to operate the treatment facilities. This paper analyzes problems that exist in the EIA system in China, and it describes the Cleaner Production Index and Evaluation System, which is being proposed by environmental authorities in China to evaluate EIA projects based on cleaner production criteria. The paper also suggests how cleaner production analysis can be integrated into the EIA system to improve it.