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281.
Nora M. Znotinas Keith William Hipel 《Journal of the American Water Resources Association》1979,15(1):44-59
ABSTRACT: Procedures are presented for comparing and evaluating alternative engineering designs for a particular water resources project. By using certain aspects of fuzzy set theory, it is possible to introduce both quantitative and qualitative considerations into the decisionmaking process. In addition, the viewpoints of the various interest groups involved with the water resources development can be realistically incorporated by the evaluation techniques for the alternative designs. Methods are given for eliminating undesirable alternatives and thereby obtaining a reduced set of possible feasible solutions to the problem. Because of the flexibility of the evaluation methods, the viable alternatives should not only satisfy economical, technical. environmental and other types of constraints, but these possible solutions should be politically feasible as well. A method is formulated for checking the sensitivity of the feasible results with respect to the factors that are considered in the analysis. 相似文献
282.
James Fulton William L. Chase 《Journal of the American Water Resources Association》1979,15(2):426-435
ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed. 相似文献
283.
William E. Cox Keith A. Argow 《Journal of the American Water Resources Association》1979,15(3):728-739
ABSTRACT: The issues involved in the conflict between the rights of the public and those of riparian landowners are examined by reviewing the public access situation with regard to inland streams in the State of Virginia. Consideration is given to the legal framework defining access rights and to the attitudes of riparian landowners regarding the access question. Existing provisions of law suggest only limited recognition of public rights, but this law is incompletely developed. A considerably broader concept of public rights could be developed within the existing framework due to the existence of unresolved questions. The analysis of landowner attitudes is based on a survey of a sample of riparian owners chosen from throughout the state. The questionnaire used in the survey contained 123 questions in a variety of areas, including landowners' perceptions of public rights, problems encountered as the result of recreational water use, attitudes toward state designation and protection of scenic rivers, and the acceptability of alternatives for increasing public access. Although the survey results indicate substantial acceptance of the concept of public use, the landowners expressed concern over governmental control of land use and did not indicate a generally acceptable means for increasing public use. 相似文献
284.
William G. Wilber Joseph V. Hunter 《Journal of the American Water Resources Association》1979,15(3):790-800
ABSTRACT: A three-year study has been conducted on a 4.6 mile stretch of the Saddle River near Lodi, New Jersey. The primary objectives of this investigation were (1) to provide baseline information on the concentration and distribution of heavy metals in bottom sediments of the Saddle River; (2) to qualitatively evaluate which parameters affect this distribution; and (3) to determine the effect of urbanization on the concentration and distribution of these materials. Significant enrichments of several heavy metals were observed in bottom sediments of the lower Saddle River near Lodi, New Jersey, as compared to the upper Saddle River. Attempts to correlate metal concentrations in bottom sediments with chemical-oxygen demand were not successful in demonstrating a relationship between these two factors. Metal concentrations were found to be strongly dependent upon particle size. In general, metal concentrations in bottom sediments increased with decreasing partical diameter. However, metals enrichment was observed to be considerably greater in the larger sediment fractions studied (>420μ) than the smaller sediment fractions as one proceeded downstream through the urban area. Since the larger sediment fractions are least effected by scour and transport they may best reflect the effect of urbanization on the distribution of heavy metals over an extended period of time at a given location. 相似文献
285.
William E. Hammitt 《Environmental management》1980,4(5):425-431
Bogs are of interest to outdoor recreationists, but little information exists concerning how recreation resource managers might manage these areas to enhance visitor benefits. This study evaluates bog visitor characteristics and experiences, visual preferences, and reasons for visiting. Implications for recreational resource management of bogs include the location and design of boardwalk trails and management of understory vegetation to meet the visual preferences and motives of bog visitors. 相似文献
286.
287.
David M. Meko Charles W. Stockton William R. Boggess 《Journal of the American Water Resources Association》1980,16(4):594-600
ABSTRACT: Indices of annual diameter growth of trees were used to reconstruct drought in southern California back to A.D. 1700. A regional Palmer Drought Index served as predictand and tree-ring indices from eight sites as predictors in multiple linear regression analyses that yielded the prediction (reconstruction) equations. The regression explained 69 percent of the variance in Palmer Index in the period of calibration. The long-term reconstruction indicated that drought was rare in the first half of the current century relative to other discrete 50-year periods, and that based on evidence to date the last half of the 20th century may well turn out to be the most drought prone since A.D. 1700 in southern California. 相似文献
288.
This article documents the general need to reuse water reclaimed from sewage effluents for beneficial purposes and then considers in detail which specific uses will be most beneficial. The analysis begins by describing five levels of wastewater treatment: primary, secondary, tertiary, advanced, and advanced plus complete treatment. Next, five major uses for reclaimed water are identified: groundwater recharge, industrial use, irrigation, recreational lakes, and direct municipal reuse. Subcategories of reuse falling under each of the five major reuse categories are also identified and discussed. The analysis then proceeds to review significant literature available on health and environmental effects, treatment and distribution costs, and public opinion concerns in relation to each of the five major uses and their related subcategories. The paper concludes with a cumulative numerical analysis of the disbenefits associated with each specific type of reuse summed over the health effects, environmental effects, treatment costs, distribution costs, and public opinion concerns. Uses of reclaimed water for industrial purposes and for irrigation of fodder and fiber crops are found to be most beneficial by the analysis here employed, and use for aquifer recharge and direct municipal reuse are found to be least beneficial. 相似文献
289.
290.