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941.
Michael Donovan Charles A. Job William C. Sonzogni 《Journal of the American Water Resources Association》1981,17(1):23-28
ABSTRACT: The Illinois v. Milwaukee Federal District Court decision is the most far reaching application yet of the federal common law of nuisance to interstate water pollution conflicts. Although a Federal Appelate Court recently rescinded part of the district court decision, Milwaukee must still upgrade its metropolitan sewage system to a level beyond that required by federal and state regulations. The improvements must be completed with or without federal aid. The case points out the apparent inability of the Clean Water Act, the most comprehensive federal legislation affecting the nation's water quality, to deal with certain interstate water quality conflicts. The Milwaukee decision could set a precedent for similar settlements elsewhere which may in turn affect the U.S. Environmental Protection Agency's water quality clean up program. A more integrated, ecosystem conscious approach to management of shared water resources (e.g., the Great Lakes) would help reduce the need for court decisions like Illinois v. Milwaukee. 相似文献
942.
William Whipple James M. DiLouie Theodore Pytlar 《Journal of the American Water Resources Association》1981,17(1):36-45
ABSTRACT: In urbanizing areas, the usual increase in flood flows also increases erosional capability of streams. In order to evaluate such tendencies quantitatively, 25 stream reaches were studied, and were classified as to whether erosion of the channel and banks was light, medium, or heavy. Analysis of characteristics indicated that (1) densely developed areas are correlated with greater erosion, (2) wide stream buffers of natural vegetation are correlated with lesser erosion, and (3) there is no definite correlation of erosion to slope or characteristics of soil. Erosional stream instability can be avoided by retention of storm water runoff, creating additional channel roughness or reducing channel slope during floods by drop structures, such as culverts, which restrict flow. Channel straightening and general bank protection should be minimized in such streams. Design of culverts should take such effects into consideration. 相似文献
943.
Donald J. Epp C. Edwin Young 《Journal of the American Water Resources Association》1981,17(2):215-224
ABSTRACT: Varying treatment levels to meet seasonal variation in assimilative capacity of streams can reduce total costs of treatment. A mathematical model of a Pennsylvania stream based on a theoretically sound approximation of the physical relationships underlying the distribution of DO in a river system was used to determine discharge constraints for an economic optimization model which produced estimates of sewage treatment cost savings. Increasing the number of flow periods during the year enhances cost reducing opportunities even when land application processes are considered. Also, the least cost treatment process for year around operation may not be the least costly under multiple flow period management. 相似文献
944.
LeVerne D. Hudson David J. Schaeffer William J. Tucker William H. Ettinger 《Environmental management》1978,2(6):555-559
During 1976, Illinois experienced a mild drought, of i ntensity equivalent to the once in 5 years frequency. It was anticipated that the drought would result in deteriorated water quality because dilution of point source discharges would be diminished. Furthermore, because productivity in Illinois streams is light limited, reduced runoff should result in clearer streams, higher algae levels, and greater variability in dissolved oxygen levels. In spite of these expectations, both chemical and biologic data showed that water quality in 1976 was appreciably better than that before 1975. The information provided by the Illinois water quality index (Janardan and Schaeffer 1977) coincides with biologic analyses of benthic invertebrates. The index supports and supplements the biologic data and provides a means for quantifying and integrating chemical and biologic data.The results of this study showed that the drought had little, if any, effect on statewide water quality. Although the magnitude of the drought varied across the state, water quality remained unchanged between 1975 and 1976. This may have reflected the ability of unpolluted systems to adjust to natural variations or have been an indication that there were offsetting statewide gains in pollution control in 1976 or that uncharacterized, broad-based phenomena were operating in stream ecology, or that combinations of these were in effect.Based on presentations before the American Water Resources Assocition, Illinois Section, Chicago, Illinois, June 10–11, 1977. 相似文献
945.
Nancy U. Schultz Albert Wilmarth 《Journal of the American Water Resources Association》1978,14(2):275-287
ABSTRACT: Section 208 of the Federal Water Pollution Control Act Amendments of 1972 has provided the Southwestern Illinois Metropolitan and Regional Planning Commission (SIMAPC) with a unique opportunity for comprehensive planning of the region's water quality. SIMAPC initiated the 208 study by researching available technology for the analysis of point and nonpoint sources of pollution and establishing criteria by which to judge the various technniques. This led to SIMAPC'S choice of continuous simulation of stream and reservoir water quality as the most appropriate analytical tool for their needs. A continuous simulation model was calibrated and verified on three basins in the SIMPAC region. It was then used to produce load source analysis, pollution event frequency analysis, and pollution event duration analysis for ten pollutants under existing stream conditions and then under alternative future conditions. These results enabled the weighting of pollutant sources, analysis of the effectiveness of control measures, and quantitative analysis of the marginal benefit of each alternative. 相似文献
946.
Herbert W. Greydanus 《Journal of the American Water Resources Association》1978,14(2):477-480
ABSTRACT: Most of California's precipitation falls at the wrong place in the wrong season in relation to the water needs. Redistribution and regulation are essential. Aquifer systems – groundwater basins – can provide a share of the future cyclic storage regulation. There are some differences in management concepts in using a full basin in comparison with a partially dewatered basin. Legal, water quality, and physical impacts on aquifer systems, including subsidence, are concerns. Storage may be for the benefit of overlying water users or for distant areas. Extraction during dry periods or recharge methods will require careful planning. Existing rights and uses and equitable treatment of all parties must be assured. Financial compensation may be involved. Changes in methods of operation or degree of self-determination by affected water agencies will require committed watermanship to resolve. Legislation or amendments to organic acts may be needed but much can be accomplished within existing statutes. Environmental impacts which can be avoided by not using large surface storage sites are important. Energy for pumping will be a key consideration. About 40 percent of California is underlain by aquifer systems. This resource offers major potential in overcoming the maldistribution of natural water resources. 相似文献
947.
D. T. O'Laoghaire 《Journal of the American Water Resources Association》1978,14(4):809-826
ABSTRACT: This paper describes a mathematical model, an algorithm and a computer program that were specially developed to study the problem of a water quality management system undergoing a rapidly increasing environmental stress. The model output will determine the locations, sizes and the timing of construction of new treatment plants plus an overall treatment plant operating policy so that environmental standards are maintained at a minimum cost. The model, as formulated, is a 0-1 mixed integer programming problem which is solved by decomposing it into a capital budgeting problem (solved by Little's branch and bound algorithm) and an operational policy problem (solved by linear programming). The coded algorithm (in FORTRAN 10) has been tested with a semi-realistic example. 相似文献
948.
Howard T. Odum W. Kemp Maurice Sell Walter Boynton M. Lehman 《Environmental management》1977,1(4):297-315
New concepts and insights concerning human and natural systems in the coastal zone are emerging from recent energy analysis and synthesis studies. By using new concepts for measuring the quality of energy, one can express the work of ecosystems and human economies in equivalent terms. From energy models and new energy quality evaluations, one can learn what kinds of coastal systems maximize power, are competitive, economically vital, and likely to have a survival advantage.Energy analysis and synthesis is aided by energy circuit diagrams. Models of the coastal zone that emphasize the change in external driving functions related to world energy sources provide insights and some predictive abilities that are not found in economic studies, since money flows alone do not evaluate external driving energies.This paper suggests four procedures for coastal planning: 1) calculation of investment ratio in units of equal quality to determine which projects are economic in a broad sense, 2) development of energy signatures for coastal ecosystems, 3) determination of which interface ecosystems develop the best energy flows, and 4) development of regional models that include the main features of human and natural ecosystems. 相似文献
949.
E. M. Davis D. M. Casserly J. D. Moore 《Journal of the American Water Resources Association》1977,13(5):895-906
ABSTRACT: Data were developed within a three-year period for indicator bacteria and three species of bacterial pathogens following rural storm event hydrographs. The first flush concept was confirmed in all hydrographs. Bacterial density peaking occurred at or before the hydrograph peaks. FC and FS values were higher in more developed areas than the primary rural test site and their numerical ratios followed similar trends. Chlorine demand of storm waters varied between 8 and 16 mg/l and, the ozone requirement was greater than 32 mg/l in the same waters. Aftergrowth of total coliform bacteria occurred following chlorine and ozone doses of 16 mg/l and 32 mg/l respectively. Fecal coliform, fecal streptococci, Salmonella sp., and Pseudomonas sp. all were reduced to near detectable limits by the disinfectants up to 8 days. Staphylococcus sp. demonstrated a propensity to restablish their populations. Multiple regression analysis of the bacterial groups and species in storm waters suggested the fecal streptococci to have been the most useful group in evaluating bacterial storm water quality, with staphylocci have been closely related insofar as their statistical significance was concerned. 相似文献
950.
James I. Hoffman 《Journal of the American Water Resources Association》1977,13(5):941-952
ABSTRACT: Completion of a 1270 acre recreational impoundment (Legend Lake) in the glacial sands of Menominee County, Wisconsin, produced geochemical and hydrologic alterations in some nearby natural lakes. The impoundment was produced by the construction of three dams, one of which proved to be temporary, connecting 9 natural lakes and ponds of 383 acres with 951 acres of flooded lands. Water levels were raised 3–15 feet within the impounded area. Much of the flooded area was peat rich wetland associated with the prior drainage. Water depths are less than 15 feet in 70% of the impoundment. Three seepage lakes, located less than 1/2 mile from the impoundment, experienced shoreline flooding, shoreline and soil erosion, some tree kills, and increased turbidity. These lakes also experienced concentration increases in several chemical constituents which indicate an influx of impoundment water through a regional alternation in the groundwater flow paths. The three lakes were connected by canals, and a 2.3 cfs gravity drain with an auxiliary pumping station was built to return excess water to the outflow of the impoundment. Future projects of this type would benefit from a more extensive hydrologic and geochemical analysis prior to initiation. Had environmental assessments been required at the time of this development, as they now are in Wisconsin for similar projects, some of the problems encountered might have been alleviated. 相似文献