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1.
ABSTRACT: In order to plan for land use in a lake basin to maintain or improve lake water quality, municipal planners need a method of evaluating lakeshore and watershed land use that is technically sound, objective, reasonably quick, and cheap enough to be incorporated into their time and dollar budgets. Such a system is presented. It consists of measuring and rating four lakeshore land use characteristics (type of sewage disposal system, lot size, road proximity, and intensity of public use areas), and three upland watershed land use characteristics (intensity of development, forest cover, and agriculture and open space). These seven characteristics are measured, rated, and then combined to provide a two-digit index number. This number, when compared with the indexes of other lakes in the region and interpreted with assistance from officials of the State Health and Water Resources Department, indicates on a relative basis the degree to which various land uses are contributing to accelerated, cultural eutrophication. Interpretation of the index suggests land use controls necessary to improve lake water. It supplements, and should be used with, an index of lake vulnerability to accelerated eutrophication and a comparative measure of present water quality.  相似文献   

2.
ABSTRACT: Wetlands occur in a variety of geologic, hydrologic, and topographic settings and exhibit diverse hydrogeologic characteristics. A wetland is more than an organic mat - it is an element in a larger hydrogeologic system. Three distinct but related effects of wetlands are: modifying the character of runoff from a basin, influencing the discharge/recharge relationship with the underlying aquifer, and effecting the potential for ground water development in a wetland dominated basin. An important goal of wetland research is to define the diverse roles that wetlands play in the regional hydrology and to define the geologic, hydrologic, and topographic factors that will allow meaningful distinctions among wetlands. Geologic and hydrologic factors include character and thickness of surficial materials; bedrock type; hydrologic position; permeability of organic layer; transmissivity, quality, and hydrologic connection of wetland related aquifers; ground water outflow; and depth of standing water. Topographic factors are position in the drainage basin, relative size, and absolute size of wetlands. A wetland classification to aid hydrologists and land use planners is proposed using selected factors involving hydrologic position, topographic position, and geologic type.  相似文献   

3.
Abstract: A model that incorportaes performace data about data about several wastewater management systems is discussed. From these data the excepted behavior of an individual wastewater system or group of systems can be product of the performace probabilities of its individual components. The modeel can be used on a regional scale facilitating land use planning by allowing accurate estimates of performance for a prospective wastewater management system. At this scale it can allow the impact evaluation of new wastewater technology on land use in a region.  相似文献   

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ABSTRACT: A growing concern for environmental quality paralleled with increasing demands on our forest resources has prompted the Washington State Department of Natural Resources to evaluate simulation modeling as a technique for analyzing management decisions in terms of their environmental effects. The evaluation focused on a system of integrated models developed at the University of Washington which simulate processes and activities within the forest ecosystem. A major part of the system is a hydrologic model which predicts changes in discharge, stream temperature, and concentrations of suspended sediment and dissolved oxygen based on information generated by other models representing intensive management practices. The evaluation consisted of applying the system to a 72,000 acre tract of forest land, validating the models with two years of discharge and water quality data from a 93,000 acre watershed, and determining the pertinence of hydrologic modeling for management purposes. Results show several potential uses of hydrologic modeling for forest management planning, especially for analyzing the effects of timber harvesting strategies on water quality.  相似文献   

6.
ABSTRACT: The state of Texas passed legislation in 1997 that established a process for developing a 50‐year state water plan through a bottoms‐up approach involving representation from at least 11 recommended special interest groups. Moorhouse Associates Inc. was contracted to develop and implement a Public Participation Plan for the South Central Texas Region. The two goals of the public process were to take planning information out to the public and to provide a format for bringing the public opinion back to the planning group. The overall goal of the project was to provide public input throughout the planning process that will facilitate the development of a water plan that is widely accepted by the public. By using county government to establish focus groups, participation was encouraged from all of the twenty‐one counties in the region. The tools used in the process included an Internet site, surveys, focus groups, public meetings, community group presentations, media communications, and newspaper clippings. The public participation process as implemented, maintained communication throughout the planning process and at key decision points. This ongoing communication helped alleviate an initial uneasiness with the integrated resource planning approach.  相似文献   

7.
ABSTRACT: An environmental simulation model of the Upper St. Johns River Basin, Florida, has been developed in order to predict hydrologic responses under proposed management plans. Land use projections for each of 19 hydrologic planning units are provided by a linear programming analysis of agricultural activities. Inputs to the model include rainfall, runoff, evapotranspiration (ET), aquifer properties, topography, soil types, and vegetative patterns. A water balance is developed in the uplands based on infiltration, ET, surface runoff, and groundwater flow. Valley continuity is based on stage-volume relationship for inflows and outflows and a variable roughness coefficient dependent on vegetative patterns. Land use changes form the basis for predicting hydroperiod variation under alternative management schemes. Plans are ranked according to two criteria, deviation from a natural hydroperiod and flood or drought control provided. Results indicate that (1) a single reservoir without irrigation and (2) floodplain preservation plans are superior to (3) multiple reservoir with irrigation and (4) uncontrolled floodplain plans with regard to both criteria.  相似文献   

8.
The emphasis upon comprehensive regional water resources planning in the past decade has encouraged the hydrologic engineer to take advantage of improvements in technology to develop new hydrologic engineering techniques for use in regional planning studies. The new techniques are necessary because the traditional hydro-logic engineering techniques are not always consistent with the increased scope and diversified objectives of regional planning studies. The Hydrologic Engineering Center has been involved in aiding in the development of some of these new techniques as the result of studies that have been made in cooperation with other Corps of Engineers offices. Most of the new techniques being developed emphasize computational procedures developed specifically for use with electronic computers. Applications of new techniques range from framework studies to planning of day-to-day operation criteria. Studies recently completed or in progress include: (1) development of a regional flood control site screening plan for the North Atlantic Region study; (2) use of streamflow simulation for planning and operation of the Missouri River mainstem projects; (3) development of an operation plan for the Arkansas-White-Red Rivers Reservoir System; (4) standard project flood and flood frequency estimates for the Colorado River Basin Framework Study; and several other projects which are described in more detail in the following paragraphs. One of the initial efforts in regional analysis was the formulation of procedures for determining standard project flood estimates for southern California coastal streams using generalized criteria. Techniques were developed that were readily adaptable to the computer and which would determine representative unit hydrographs, losses and standard project precipitation for any location in the study area. The resulting standard project flood estimates were consistent with the accuracy required for framework studies; however, they could be refined easily for design studies. As a result of the recent drought in the Northeastern United States, a study was made to evaluate both present and future water supply reservoirs in that region. The study consisted of computerized studies of the hypothetical operation of a large number of reservoirs as a system. The reservoirs were on many different streams throughout the region and had varying constraints, depending upon the stream and the state in which the reservoir was located. Since only preliminary data was available on the proposed reservoirs, it was not possible to refine the studies to a large degree. However, the models of each system can be easily refined as more accurate design data become available. The development of a computer-aided screening procedure for use in evaluating several hundred potential reservoir sites for the Missouri River Basin Comprehensive Framework Study is a third example of regional analysis. The adopted procedures used available physical, hydrologic, and climatologic data in estimating reservoir storage requirements throughout the basin. Because the procedure is based upon the techniques often used in more refined studies, it is expected that the results of the screening study will be very useful in future planning and design work. Shortcomings of some of the traditional techniques have helped in the development of new techniques. For maximum usefulness the new techniques should: (1) be consistent with the scope, objectives, and requirements of the overall study; (2) use all available physical, hydrologic, and climatologic data without requiring extensive data which may not be available; (3) take full advantage of the capabilities of the computer and associated data processing systems; and (4) produce results which form a firm basis for future, more detailed, planning and design studies instead of being limited in usefulness largely to the study at hand.  相似文献   

9.
ABSTRACT: The development of a regional water supply system for the six-county area of Northeastern Illinois is presented in this paper, including: 1) the establishment of regional water supply technical planning policies; 2) the development and utilization of a regional water supply computer model to identify the principal and secondary sources of water supply for each entity in the study area, based on an apparent cost-effective source analysis; and 3) utilization of the study results to develop for the year 2010 a suggested preliminary regional water supply system. Using the findings from task 2 above, a proposed plan for overall Lake Michigan water use through the year 2010 was also developed. The effects of the proposed regional water supply system on future water levels in the deep aquifer were also discussed.  相似文献   

10.
ABSTRACT: This paper uses the fundamental values of decision makers to guide a long-term wastewater planning process at Seattle Metro, a major utility district. Multiattribute value assessment is used to elicit the objectives of several elected officials and other key decision makers. The results are structured into a fundamental objectives hierarchy and a means-ends objectives network. A set of measures to indicate the performance of planning alternatives in terms of the fundamental objectives is developed. Preliminary value tradeoffs between objectives are elicited from several elected officials. The results of these steps are useful for many aspects of long-term planning: facilitating communication about values and priorities; designing attractive alternatives that are more likely to serve stakeholder interests; identifying information needed to evaluate alternatives; clarifying the relative importance of information about different impacts; providing a basis for quantitative evaluation of the alternatives with multiple objective analysis; and focusing attention on key tradeoffs that will affect the choice of alternatives.  相似文献   

11.
ABSTRACT Water resources planning has emphasized the consideration of alternatives in the formulation of goals and objectives. With greater availability of data and projection models, optimization of plans is now much nearer to accomplishment. In contrast to these favorable aspects of planning, increased complexity of plans and large number of alternatives serving differing sets of goals have extended the time horizons from initial plan formulation to eventual implementation. In this paper a man-machine strategy is proposed to reduce the time required for decision making and conflict resolution. A panel of representatives of the decision makers, influentials and publics involved are selected and brought through a series of dynamic planning steps that simulate real time decision making. Computer interaction graphics is used to visualize the decision making process and to illustrate where and why conflict arises. A mechanism for resolution of conflict and retention of consistency in policy formulation using a cognograph is described.  相似文献   

12.
ABSTRACT: A nonlinear multilevel transportation model is developed to study large-scale allocations in a water resources system. The model uses a modified transportation matrix formulated with nonlinear cost functions as the basic subregional model and the goal coordination method for multilevel decomposition and optimization of the overall regional system. The model is applied to projected water requirements for Salt Lake County in 1985. Sources of water supply - surface water, ground water, import water, and reuse of reclaimed wastewater on a restricted basis - are available to satisfy water requirements for municipal, industrial, and agricultural sectors in four subregions. The conjugate gradient projection method is used to optimize the first level subregional models having cost functions of the form of C = aXb, and the second level problem is solved using the conjugate gradient method.  相似文献   

13.
ABSTRACT: A computer program (MAPS - Methodology for Areawide Planning Studies) has been developed by the U.S. Army Corps of Engineers, Waterways Experiment Station to assist planners in producing a comprehensive array of alternatives without sacrificing the detail and accuracy of the analyses. MAPS is a set of computer based models which can be used to simulate the water resource alternatives and to develop planning level design and cost estimates. Two application examples are discussed. The Salinas-Monterey (California) Urban Study sought to identify and determine cost of combinations of water source, transmission, and treatment to meet an array of water needs in future years. The Nashville (Tennessee) Urban Study had similar objectives but the output was prepared on a service area basis for more than 40 such units. Using MAPS it was possible to prepare planning level design and cost estimates for a very large number of alternatives.  相似文献   

14.
Since the publication of Rachel Carson's Silent Spring in 1962 there has been a rapidly growing public concern over widespread contamination of the environment with hazardous wastes. In recent years scientific findings on the ecological effects of various hazardous substances have posed several important questions. What exactly are hazardous wastes? Can these substances be disposed of in a technically feasible, economical, and safe way with assurance that they have been permanently eliminated from the ecosystem? What compositional alterations or movements of the hazardous wastes occur in water, soil, or air systems? What effect will these wastes have on the water, soil, or air systems? What effect will these wastes have on the water, soil, or air properties? Consequently, a University of Louisville study has developed a relevant definition of hazardous wastes for the Environmental Engineering profession together with priority of concern rating systems to delineate the degree of environmental impact imposed on a total ecosystem by a hazardous waste and the feasibility of disposing of hazardous substances at specific landfill sites. It is felt that refinements of the priority of concern rating systems offered here may provide a sound basis from which procedural decisions may be structured to establish future national hazardous waste disposal sites.  相似文献   

15.
ABSTRACT: Piped water supply and sewerage have been taken almost for granted in the developed countries. However, most people in the United States have little knowledge of the condition of public health amenities in the developing countries. The paper reviews the importance, background and current status of water and wastewater facilities in India. The relative situation in urban and rural areas, conventional practices in environmental hygiene, the programs for improvement and the problems involved with possible solutions are given. The case history of a town is also included for illustrative purposes.  相似文献   

16.
ABSTRACT. Planning an optimal system of activities for generating economic goods and services within an existing natural resource capacity is a difficult problem to solve. A mathematical programming model with the capacity to check multiple resource demand and supply compatibility over many time periods was developed for the solution to this type of problem. The characteristics of natural resource supply and the demand of activities were utilized to reduce the number of time periods and to minimize the loss of the dynamic reality of the problem. Reduction in the number of time periods extended the capability of the model to the solution of complex resource planning problems without oversimplification.  相似文献   

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ABSTRACT: By field investigations and planning, it is profitable to rehabilitate gravel pits as recreational lakes in urban areas. Some of the important aspects to be considered are topography, soil, surface water and groundwater. A case study is presented and some general guidelines in the rehabilitation process are given. This kind of a use for derelict land is important at the present time as there is a growing demand for recreational lakes in urban areas.  相似文献   

19.
ABSTRACT: The density and distribution of land uses has important consequences for the planning of sewerage systems and for the costs of these systems. This paper examines these consequences using a simplified service area model. The model determines the area to be served by a central waste treatment plant, where alternative on-lot disposal systems are also available. The model is applied to various urban area configurations, which are summarized by their total populations and by their population density distributions. Both minimum regional cost and minimum local cost service area configurations are determined. In addition, the sensitivity of the model to the parameters of the cost and population density functions is assessed. It is found that the model is most sensitive to the parameters of the collection cost function.  相似文献   

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