CAPITAL COST OF RURAL WATER DISTRIBUTION SYSTEMS1

ABSTRACT: The cost of water service to rural residents is very high compared to urban areas. This is true even after subsidization by Farmers Home Administration (FmHA) loans and grants. Capital cost data on 44 projects financed by the Ohio office of the FmHA during the period August 1968 to January 1977 are used to derive cost equations for 26 components of rural water distribution systems. These components represent 92 percent of the capital cost of the pipeline distribution systems studied. The data can be used to economically design rural water supply systems from a capital cost viewpoint. More data are needed on operation and maintenance costs as well as central and cluster well costs before totally economic system designs can be undertaken.     

CAPITAL COSTS OF RURAL WATER SYSTEMS: AN EMPIRICAL APPROACH1

ABSTRACT: In the last two decades the federal government has provided substantial capital to construct rural water distribution systems. Loans at subsidized interest rates and front-end grants through the Farmers Home Administration have been the main source of this capital. Recent federal policy redirections have reduced substantially the availability of grants and subsidized loans. Because of design and material differences, capital cost estimates from urban systems are not uniformly applicable to rural water services. This study presents an econometric analysis of capital costs, using Illinois rural water system construction contract bids. Cost equations by systems components representing 90 percent of capital costs are estimated. The type of information developed here can be used in initial planning and optimization design models contributing to the efficient provision of rural water services.     

ECONOMIC DESIGN OF CENTRAL WATER SUPPLY SYSTEMS FOR MEDIUM SIZED TOWNS1

ABSTRACT. Adequate and good-quality water supply for medium sized towns is costly when there are insufficient quantity and low quality of groundwater or surface water. In a central water supply system serving a number of towns, the economies of scale may permit a sufficient and good-quality supply at lesser rates. Such a system has the flexibility of supplying rural population through small service lines. The system may be an interbasin or intrabasin conveyance depending on the location of a suitable water source and the economics of the supply network. Seven cost elements are pertinent to the optimum or least-cost design of network consisting of pipelines and pumping stations. The relevant cost functions are based on the available data gathered from various sources. Water conveyance costs are calculated for various flow rates, pipeline diameters, flow variabilities, static heads, and interest rates, thus providing a measure of sensitivity of the conveyance cost to such variations. The economies of scale, the sensitivity of optimum unit conveyance costs, and variations in unit costs with change in cost functions are useful in making a feasibility study for a proposed conveyance system.     

THE DYNAMICS OF WATER RESOURCES MANAGEMENT IN AN URBAN ENVIRONMENT1

The traditional approach to water resources management for urban areas has been based on the examination of needs and the design of separate facilities for water supply, drainage, and waste water collection and treatment. The complexity and interaction among the separate systems required by a metropolitan area has complicated their management and promoted research interest in developing a methodology for better coordination. However, a more thorough evaluation of the problem reveals the real research need to be both more complicated and different in character than the problem in systems analysis suggested by the first superficial glance. Water management relates to the much broader problem of community design; when, where, and in what manner should new urban development take place. Furthermore, the character and needs of areas within the metropolis are constantly changing. The key distinctiveness of urban water management is the imperative for design and operation flexibility. The key research need is to develop new designs, operation procedures, and institutional arrangements to make the flexibility demanded by a dynamic urban community possible.     

DEVELOPMENT OF DESIGN STORM HYETOGRAPHS FOR CINCINNATI,OHIO1

ABSTRACT A synthetic storm rainfall hyetograph for a one-year design frequency is derived from the one-year intensity-duration curve developed for Cincinnati, Ohio. Detailed rainfall data for a three-year period were collected from three raingages triangulating the Bloody Run Sewer Watershed, an urban drainage areas of 2380 acres'in Cincinnati, Ohio. The advancement of the synthetic storm pattern is obtained from an analysis of the antecedent precipitation immediately preceding the maximum period of three selected durations. Rains which produced excessive runoff at least for some duration were considered only. The same approach can be used for other design frequencies. The purpose of this study is to provide synthetic storm hyetographs to be used as input in deterministic mathematical models simulating urban storm water runoff for the design, analysis and possible surcharge prediction of sewer systems.     

ANALYZING THE IMPACT OF LAND USE ON SEWER SERVICE AREA PLANNING1

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.     

AN INTEGRATED APPROACH TO WATER RESOURCES DEVELOPMENT OF THE TEHRAN REGION IN IRAN1

ABSTRACT: In this paper, a system approach to water resources development in Tehran Metropolitan Area, with its complex system of water supply and demands, is discussed. Water resources in this region include water storage in the Lar, Latyan, and Karaj reservoirs, the Tehran aquifer, as well as water discharge in local rivers and in drainage channels (mainly supplied by urban runoff and wastewater). This study consists of three phases of long‐term water resources planning and management in the Tehran metropolitan area. In each phase, a different level of details among different components of the system is considered. In the first phase, optimal operating policies for Tehran reservoirs and a decision support system are developed. In the second phase, interactions between surface and ground water resources as well as surface runoffs and wastewater disposal in different subareas are investigated. The water table fluctuations as a result of implementing sewerage collection project was also simulated. In the last phase, long‐term scenarios for water resources and agricultural development in the Southern part of Tehran are defined, and the effects of each scenario on the quality and quantity of surface and ground water resources are studied.     

AN IMPLICIT APPROACH TO PRICING AGRICULTURAL WATER TRANSFERS TO URBAN USES1

ABSTRACT: The increased agricultural efficiency of the American farmer has been a substantial impetus to this nation's rapid urbanization. In many western regions where total water supplies are limited, urbanization has required the transfer of heretofore agricultural water rights to the urban use. A major problem in such transfers has been the value or price of the water. A management level model of a typical urban water system was developed to optimize water supply, distribution, and wastewater treatment alternatives. The values of agricultural transfers were determined as the cost advantages of increasing allowable reuse levels of urban effluents which imply the use of a downstream right. This procedure is justified by the economic theory of alternative cost. Results for a test application to the Denver, Colorado area indicate values on the order of $1,000 per acre-foot of transferable water depending on effluent water quality restrictions and operational policies.     

FINANCING FEDERAL WATER DEVELOPEMNT PROJECTS AND SHARING THE COSTS1

ABSTRACT: The Federal Government's interest and involvement in water resource development in discussed in the context of project financing and cost sharing. After drawing a clear distinction between the two issues - who puts up the money, and who repays over time - the authors survey a number of Federal acts from which have evolved nearly 200 separate cost-sharing rules. Selected cost sharing and financing issues discussed include consistency in policies, rehabilitation of urban water supply systems, multipurpose water quality projects, and ground water management. Two proposals for cost/finance sharing reform introduced in the 96th Congress are discussed in detail and their impacts compared with current policy. The joint venture approach (Administration proposal) results in an effective composite cost share which changes significantly but not drastically (from 19 to 35 percent non-Federal share for a hypothetical project). The block grant approach (Domenici-Moynihan proposal) would alter the regional distribution of Federal water developement funding from the South and West to the Northwest and North Central States.     

WATER QUALITY SAMPLING SCHEMES FOR VARIABLE FLOW CANALS AT REMOTE SITES1

ABSTRACT: Growing interest in water quality has resulted in the development of monitoring networks and intensive sampling for various constituents. Common purposes are regulatory, source and sink understanding, and trend observations. Water quality monitoring involves monitoring system design; sampling site instrumentation; and sampling, analysis, quality control, and assurance. Sampling is a process to gather information with the least cost and least error. Various water quality sampling schemes have been applied for different sampling objectives and time frames. In this study, a flow proportional composite sampling scheme is applied to variable flow remote canals where the flow rate is not known a priori. In this scheme, historical weekly flow data are analyzed to develop high flow and low flow sampling trigger volumes for auto‐samplers. The median flow is used to estimate low flow sampling trigger volume and the five percent exceedence probability flow is used for high flow sampling trigger volume. A computer simulation of high resolution sampling is used to demonstrate the comparative bias in load estimation and operational cost among four sampling schemes. Weekly flow proportional composite auto‐sampling resulted in the least bias in load estimation with competitive operational cost compared to daily grab, weekly grab sampling and time proportional auto‐sampling.     

USE OF MICROCOMPUTERS FOR THE MANAGEMENT OF WATER QUALITY DATA1

ABSTRACT: Information on raw water quality, treatment process removal efficiency, and distribution system monitoring is essential to the proper management and operation of a water utility system. Microcomputer hardware and software systems using commercially available data base management systems (DBMS) have emerged within the last few years as an effective means of managing, analyzing, and displaying water quality data. Understanding hardware, software, and training requirements is essential to the proper use of these systems. Three types of data base design are common: relational, hierarchical, and network. Only the relational type of data base architecture is widely implemented on microcomputer DBMS. In this paper two examples of the application of DBMS to water utility problems are presented. One example deals with collection and analysis of data concerning the water quality of the Mississippi River. The second example deals with the DBMS as a means of analyzing water quality data in the North Penn Water Authority (NPWA) distribution system.     

A STORM WATER MANAGEMENT MODEL FOR URBAN AREAS IN KUWAIT1

ABSTRACT: A comprehensive study was conducted to implement the Storm Water Management Model (SWMM) for urban areas in Kuwait. The updated version of the model designed to run on an IBM Personal Computer and compatibles (PCSWMM3.2C) was utilized. The study revealed that urban runoff simulation in arid areas by the SWMM model is a powerful and efficient tool in designing drainage systems and as such, a viable replacement of the commonly used rational method. It was found that only the streets and paved areas that are hydraulically connected to the drainage system contribute to runoff. Fine and coarse discretization approaches were used in the study. The difference between the hydrographs simulated by the two approaches were relatively small. The performance of the existing drainage system and the accuracy of the design method used were tested using a 25-year storm. The result of the simulation revealed that the storm sewers were oversized by factors ranging from 1.2 to 3.6. The SWMM model was used to estimate the storm water runoff volume collected from all urbanized areas in Kuwait City. The annual expected harvested runoff water was found to be significant; however, the quality of runoff water needs to be assessed before a decision is made on its reuse.     

A NET BENEFIT MODEL FOR RECREATION PLANNING AT DRINKING WATER RESERVOIRS1

A management model was developed for determining levels of recreation activities at public drinking water reservoirs. Quabbin Reservoir, located in central Massachusetts, served as a case study for the model. An interdisciplinary research team was formed to study the impact of selected recreation activities on water quality, public demand and willingness to pay for selected recreation activities, carrying capacity constraints, and the economic cost/benefits associated with increases in recreation at the Quabbin Reservation. Study variables were integrated into a quadratic programming model, producing the number of participants that corresponds to maximum net benefits for specific development packages on design days. The recreation mix associated with maximum net economic benefits was found to be cost-effective (assuming the use of reasonable entrance fees) and not deleterious to water quality. However, as a result of the findings of a related study, it was recommended that nutrients, particularly from wastewater, not be permitted to enter the reservoir, since the current phosphorous level may be at a critical point. Management techniques that would safeguard against this occurrence were recommended. The model was sensitive to management objectives; recommendations were limited to activities that would not lower the existing high quality of Quabbin water.     

Benefit–Cost Analysis of StormwaterQuality Improvements

The major purpose of this paper is to explore the potential value of benefit–cost evaluation for stormwater quality management decisions at a local level. A preliminary benefit–cost analysis (BCA) screening method is used for maximum extent practicable (MEP) analysis, identifying promising management practices, and identifying societal and economic tradeoffs for local stormwater problems. Ballona Creek, a major urban storm drain in Los Angeles, California, USA, is used to illustrate the practicality of the benefit–cost evaluation. The Ballona Creek example demonstrates the economic limits of stormwater management in an urban region and attests to the value of coordinated basinwide management compared to uncoordinated management by individual landowners. Evaluation results suggest that in urban areas, the benefit of stormwater quality improvements might be far greater if accompanied by comprehensive redesign of drainage networks and neighboring land uses. In this case, benefit–cost analysis is found to be useful for evaluating and understanding stormwater management alternatives despite the uncertainties in characterizing stormwater quality and the effects of stormwater management on improving receiving water quality.     

ECONOMIC APPRAISAL OF A GROUND WATER DEVELOPMENT PROJECT1

A ground water development project in the northern part of Thailand was appraised by means of benefit-cost analysis. This is the first project in Thailand to develop ground water for irrigation purposes and it is also the first project which made use of an underground PVC pipe water distribution system. Results indicate that the project is economically feasible. In comparing different water distribution systems, it is also found that distribution by means of underground PVC pipes is more economical compared to an open ditch system if the life of the latter is relatively short and the rates of inflation are high.     

Analysis of the quality of the recovered paper from commingled collection systems

The need to increase the recovery rates of recyclables from households, reducing at the same time the collection costs, has favoured the spreading of commingled collection systems. This study presents a thorough analysis of the quality of a secondary source of recovered paper of a Spanish newsprint mill, imported from the United Kingdom, where these systems are widely practiced. The results show that the quality of recovered paper from commingled systems is very far from the quality obtained with selective systems: the unusable material content vary from 1% to 29% (11.9% on average) compared to less than 1%. Larger materials recovery facilities (MRFs), less oversaturated and with advanced sorting techniques, have demonstrated to be able to render better qualities, the unusable material content varying from 0.3% to 16.6% (8.1% on average). However, the quality is still far from contamination levels typically found with selective systems, especially in terms of non-paper components. This fact limits significantly the use of this recovered paper for graphic paper production where the major potential for an extended use of recovered paper in papermaking lies. Furthermore, there is a discussion on the cost efficiency of these systems and how the legislation and private or public initiatives are affecting the spreading of these systems, especially in the United States and the United Kingdom.     

THE IMPACT OF WATER QUALITY OBJECTIVES ON URBAN WATER SUPPLY PLANNING1

ABSTRACT: Optimal policies for supplying rapidly expanding urban centers with additional water supplies are shown to be dependent on water quality goals for the urban effluent. As effluents are required to meet increasingly stringent standards, the unit costs associated with adding capacity to existing wastewater treatment systems to renovate some waters for reuse are shown to substantially decrease. A nonlinear elimination algorithm is developed to delineate optimal policies. A model employing the technique was applied to the wastewater treatment system of a typical urban system and the water quality objectives varied. A comparison of costs with and without various levels of reuse were made and unit costs of reused water under these conditions determined.     

LEAST COST SOLUTIONS TO THE PROBLEM OF EFFLUENT ABATEMENT IN URBAN SYSTEMS1

ABSTRACT: There is a significant misallocation of resources in the construction and operation of municipal sewage treatment systems in North America. Central to this misallocation is the inadequate evaluation of alternative treatment technologies, alternative distributions of responsibility for waste treatment, and alternative mechanisms for inducing compliance with treatment system requirements. Perverse incentives in the current institutional structure limit the scope of alternatives examined by decisionmakers. Determination of the least cost solution to the problem of urban effluent abatement requires mathematical modeling for the delineation of optimal treatment strategies on a system wide basis. The adoption of modern methods of systems analysis can identify significant opportunities for the reduction of economic waste in the treatment of municipal sewage.     

ALTERNATIVES TO THE USE OF AGRICULTURAL DRAINAGE WELLS1

ABSTRACT: A large number of agricultural drainage wells (ADWs) are located in north-central Iowa. These wells permit sediments, pesticides, nitrate, and bacteria in surface and subsurface drainage water to enter regional aquifers that are currently being used for drinking-water supplies, mostly by rural families and communities. This paper reports some possible alternatives to control the entry of surface and subsurface drainage waters into groundwater systems, and describes a methodology to make comprehensive economic feasibility studies of alternative drainage outlets. The estimated cost of providing main subsurface drains varied from $220 to $960 per hectare. If the use of ADWs was completely eliminated without providing alternative drainage, it is estimated that the average annual loss to the farmers of the area would be at least $270 per hectare in reduced crop yields. Of course, losses would be weather dependent and highly variable. Management practices to reduce the pollutant load in water draining to ADWs are also discussed.     

DATA REQUIREMENTS OF A WATER QUALITY MANAGEMENT PROGRAM1

ABSTRACT: Routine data collection currently consumes a large amount of the total resources devoted to water quality management. All too often data collection becomes an end in itself, with little thought given to the purpose of the data collection. The problem generally stems from a lack of proper routine surveillance system design and a failure on the part of the designers to initially identify the data needs of the management program. This study attempts, in a general way, to delineate the data needs of a water quality management program. This first required an identification of the activities involved in water quality management. The activities were then discussed in terms of the types of information needed to successfully complete their assigned tasks. Several detailed examples are given. The results of the discussion are summarized and several strategies are proposed to relate the results to surveillance system design.