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1.
An econometric model was developed to measure the influence of several environmentally oriented variables and an ownership variable upon the average total residential water costs for New Hampshire water systems. The implementation of leak detection programs, localized institutional rules and regulations, and hazardous waste inspection programs were statistically significant in influencing residential water costs. The existence of a water conservation program did not statistically influence these per unit costs. Water systems that were privately owned resulted in per unit costs that were higher relative to firms that were publicly owned.  相似文献   

2.
ABSTRACT: This paper examines the cost of water supply for small and mid-sized private water utilities. An econometric approach was employed in which data on utility costs and characteristics were used to estimate a total water supply cost function from which average and marginal costs were derived. The results suggest that although average and marginal costs decline with output, the rate of decline rapidly approaches zero, and unit costs therefore appear to remain relatively constant over a wide range of output. Implications of the results for pricing policy are examined.  相似文献   

3.
ABSTRACT: Several factors theoretically affect the cost behavior of water systems. These factors include scale, consumer density, and per capita usage. This analysis examines the several possible influences on the unit costs of water service. The statistical analyses indicate that among the factors of scale, per capita use, and consumer density, only the first two factors are important influences on water system costs. Water consumers appear to benefit from being served by large systems and being located in service areas characterized by relatively high per capita consumption. There is little statistical evidence indicating that more dense areas can be provided water service at lower costs than less dense areas.  相似文献   

4.
ABSTRACT: This paper synthesizes and interprets data pertaining to the evolution of average water revenue, water use, and the average cost of water supply in the City of Santa Barbara, California, from 1986 to 1996, a period which included one of the most devastating droughts in California this century. The 1987–1992 drought hit the study area particularly hard. The City of Santa Barbara was dependent exclusively on local sources for its water supply. That made it vulnerable as the regional climate is prone to extreme variability and recurrent droughts. The 1986–1992 drought provided a rare opportunity to assess the sensitivity of municipal water use to pricing, conservation, and other water management measures under extreme drought conditions. Our analysis indicates that the average cost of water rose more than three-fold in real terms from 1986 to 1996, while the gap between the average cost of supply and the average revenue per unit of water (= 100 cubic feet) rose in real terms from $0.14 in 1986 to $ 0.75 in 1996. The rise of $3.08 in the average cost of supplying one unit of water between 1986 and 1996 measures the cost of hedging drought risk in the study area. Water use dropped 46 percent at the height of the drought relative to pro-drought water use, and remains at 61 percent of the pre-drought level. The data derived from the 1987–1992 California drought are unique and valuable insofar as shedding light on drought/water demand adaptive interactions. The experience garnered on drought management during that unique period points to the possibilities available for future water management in the Arid West where dwindling water supplies and burgeoning populations are facts that we must deal with.  相似文献   

5.
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.  相似文献   

6.
The ability to pay for water and wastewater services is a growing issue in the developed world. To this point in time, utilities have helped customers grappling with affordability issues using different types of customer assistance programs (CAPs). Income‐based billing approaches differ from CAPs in that bills are structured so as to be affordable for customers at the outset. Recently, the City of Philadelphia implemented an innovative program to work towards resolving the affordability problem in their city using income‐based billing. This tiered assistance program or TAP structures bills for water, wastewater, and stormwater services to program enrollees’ income. Given the innovative nature of the program, this paper describes the rollout of TAP and assesses the impact of the program on customers and utility revenues. The paper closes with a critical assessment of TAP and considerations for utilities evaluating the implementation of similar programs.  相似文献   

7.
Adjusting for the operational environment in studies of performance measurement is very important, otherwise the analysis may lead to unrealistic scores, especially when its influence on costs is high, such as in the water utilities. In this paper, we study the influence of exogenous variables on the water utilities performance by applying conditional efficiency measures based on the order-m method and its probabilistic formulation. We use a sample of 66 water utilities operating between 2002 and 2008, representing about 70% of the Portuguese population. Our research suggests that inefficiency of Portuguese water utilities is substantial for some utilities: several exogenous variables might influence it considerably. For example, regulation has a positive influence on efficiency but when drinking water supply and wastewater services are provided by the same utility or when the wholesale and retail activities are provided together, the performance is lower. The effect of ownership is inconclusive and the variables residential customers, water source, peak factor, and density of customers have a mixed influence on performance which varies according to their scores.  相似文献   

8.
ABSTRACT: The Rio Grande Valley National Water-Quality Assessment study unit encompasses about 45,700 square miles in Colorado, New Mexico, and Texas upstream from the gaging station Rio Grande at El Paso, Texas, and includes surface-water closed basins east of the Continental Divide in New Mexico, and the San Luis Closed Basin in Colorado. The mean annual precipitation ranges from less than 6 to more than 50 inches; potential evapo-transpiration ranges from less than 35 to more than 80 inches per year. Land use is mainly rangeland, forest land, and cropland. Total irrigated acreage in 1990 was about 914,000 acres and water use was about 3,410,000 acre-feet. Two structural settings are found in the study unit: alluvial basins and bedrock basins. The alluvial basins can have through-flowing surface water or be closed basins. The discussion of streamflow and water quality for the surface-water system is based on four river reaches for the 750 miles of the main stem. The quality of the ground water is affected by both natural process and human activities and by nonpoint and point sources. Nonpoint sources for surface water include agriculture, hydromodification, and mining operations; point sources are mainly discharge from wastewater treatment plants. Nonpoint sources for ground water include agriculture and septic tanks and cesspools; point sources include leaking underground storage tanks, unlined or manure-lined holding ponds used for disposal of dairy wastes, landfills, and mining operations.  相似文献   

9.
Abstract: Agricultural runoff, such as dissolved mineral salts and selenium, creates pronounced downstream impacts to agricultural producers and to wildlife. The ability to manage these problems efficiently depends critically on the institutional pricing structure of irrigation water delivery agencies. An important characteristic of irrigation water delivery is whether irrigators pay per unit of water received or make one payment regardless of the quantity of water received. In this study we compare the effectiveness of agricultural runoff reduction policies in two regions that employ these different water pricing structures. We find that reduction policy is more effective and can be achieved at a lower cost when water is priced on a per unit basis and that growers have greater incentive to act on their own to reduce runoff problems. Operating under a per unit pricing system encourages water conservation and runoff reduction, which creates public benefits that are not achieved under the single-payment, fixed allotment method of irrigation water delivery.  相似文献   

10.
ABSTRACT. A rationale is set forth for requiring and/or encouraging the consolidation or regionalization of all systems beneath certain population size levels based on the small water systems’ capability to produce an adequate supply of safe drinking water at a reasonable cost to customers. Estimates for basic costs of water service including personnel, other operation and maintenance and capital are made and a range of water rates is suggested based on reasonableness and acceptability to customers. Guidelines are then drawn for a moderate rate of $10.00 per month and an upper limit rate of $15.00 per month to show the sizes at which public water systems might be expected to achieve fiscal viability. Finally, recommendations are made to State and Federal governmental agencies concerning possible legislation, plans and programs to achieve better public water service through the regionalization or consolidation of small public water systems.  相似文献   

11.
ABSTRACT: The continuous availability of ground water to riparian phreatophytic vegetation results in large evapotranspiration (ET) losses in summer. Chemical or physical eradication of this vegetation can have undesirable environmental side effects. Spraying phreatophyte foliage with a nontoxic antitranspirant (AT) may reduce transpiration without eradication. Transpiration rate per unit leaf area was similar for several phreatophyte species, but ET per unit land area of phreatophytes depneds more on stand density than species. The mean ET for saltcedar in June was 8.1 mm/day measured by Bowen ratio, compared with 7.9 mm by lysimeters. ATs and growth-retardants reduced transpiration by over 50 percent in laboratory tests where foliage was thoroughly sprayed. In the field AT sprayed by a back-pack mistblower reduced ET by 20–35 percent initially and 10 percent after a month. No ET reduction occurred when AT was sprayed by helicopter on saltcedar, because excessive droplet size and heavy salt deposits on the foliage resulted in poor spray adherence. Wax-based AT was relatively nontoxic to fish and wildlife. Dissolved oxygen could be reduced for aquatic life, but further AT dilution in streams and ponds would minimize this. Helicopter spraying may affect bird nests and egg hatchability. Although ATs significantly reduce ET, their high cost and spraying difficulties preclude current use on phreatophytes. With improvement they may economically help to conserve water in riparian areas in future years.  相似文献   

12.
This article asks three connected questions: First, does the public view private and public utilities differently, and if so, does this affect attitudes to conservation? Second, do public and private utilities differ in their approaches to conservation? Finally, do differences in the approaches of the utilities, if any, relate to differences in public attitudes? We survey public attitudes in California toward (hypothetical but plausible) voluntary and mandated water conservation, as well as to price increases, during a recent period of shortage. We do this by interviewing households in three pairs of adjacent public and private utilities. We also survey managers of public and private urban water utilities to see if they differ in their approaches to conservation and to their customers. On the user side we do not find pronounced differences, though a minority of customers in all private companies would be more willing to conserve or pay higher prices under a public operator. No respondent in public utility said the reverse. Negative attitudes toward private operators were most pronounced in the pair marked by a controversial recent privatization and a price hike. Nonetheless, we find that California’s history of recurrent droughts and the visible role of the state in water supply and drought management undermine the distinction between public and private. Private utilities themselves work to underplay the distinction by stressing the collective ownership of the water source and the collective value of conservation. Overall, California’s public utilities appear more proactive and target-oriented in asking their customers to conserve than their private counterparts and the state continues to be important in legitimating and guiding conservation behavior, whether the utility is in public hands or private.  相似文献   

13.
The purpose of the study was to use economic analysis in determining the ability of a small strip mining company to incure the financial burden of carrying out various alternative mine drainage abatement programs. The quantity and quality of water with which the company has to deal were determined and treatment and diversion programs were costed out. The company's market area and the market structure were analyzed. It was found that pricing policies were determined by a dominant firm, so the target company had no control over its price per ton of coal. The costs and revenue of the firm were analyzed for the period 1960-1970 and, even without a water quality program, losses were incurred in six out of eleven years. Analysis of the average cost curve indicates that the per unit cost could have been reduced by increasing output thereby increasing efficiency. The conclusions of the study were that the small company could not unilaterally implement mine drainage programs because the added costs would seriously worsen its already precarious financial position. Even uniformly enforced legislation might reduce the small firms competitive position because of economies of scale associated with the large treatment facilities used by big mining companies.  相似文献   

14.
ABSTRACT: The cost of the liquid wast treatment measures required to meet federal as well as typical state and local regulations was examined for dairy processing plants of various sizes. Federal effluent standards were found to produce higher estimated capital costs per unit of raw material for smaller plants, even with relaxed requirements for smaller plants. State regulations limiting the effluent BOD5- concentration were also found to result in inequitable costs for smaller processors. These inequities result from economies of scale and not such factors as level of process technology employed or amount of waste produced per unit of raw material. In contrast, applying an example sewer surcharge formula did not produce inequities from economies of scale.  相似文献   

15.
ABSTRACT: The term flashiness reflects the frequency and rapidity of short term changes in streamflow, especially during runoff events. Flashiness is an important component of a stream's hydrologic regime. A variety of land use and land management changes may lead to increased or decreased flashiness, often to the detriment of aquatic life. This paper presents a newly developed flashiness index, which is based on mean daily flows. The index is calculated by dividing the pathlength of flow oscillations for a time interval (i.e., the sum of the absolute values of day‐to‐day changes in mean daily flow) by total discharge during that time interval. This index has low interannual variability, relative to most flow regime indicators, and thus greater power to detect trends. Index values were calculated for 515 Midwestern streams for the 27‐year period from 1975 through 2001. Statistically significant increases were present in 22 percent of the streams, primarily in the eastern portion of the study area, while decreases were present in 9 percent, primarily in the western portion. Index values tend to decrease with increasing watershed area and with increasing unit area ground water inputs. Area compensated index values often shift at ecoregion boundaries. Potential index applications include evaluation of programs to restore more natural flow regimes.  相似文献   

16.
This paper explores the trends in industrial water intake, discharge, recycling, and gross water use to see whether or not the 1972 Clean Water Act (CWA) has had an impact on industrial effluent discharge. Quinquennial Census data indicate that the levels of discharge, both generally and per unit of product, have been falling for as long as these data have been gathered. Trends in gross water use and recycling ratios suggest that during the 25 years of record production processes were gradually modified so that less total water was discharged and less was used per unit of output. Untreated discharge as a percent of all discharge fell fairly steadily across all industries until 1973 and continued to fall in 1978 in the major BOD-discharging industries. By 1978, 75 percent of the pulp and paper effluent and 40 percent of the food processing effluent was treated. The consistent increase in treated discharge in the pulp and paper mills, with their large component of BOD-related process discharge, was not matched by parallel trends in the steel, petroleum, and chemicals industries with their relatively smaller amounts (and percents) of process discharge. This suggests that the CWA may have been responsible in part for the change in the former. In the pulp and paper industry, there is further evidence that the CWA has influenced wastewater discharge. Although, for the century as a whole, pulp and paper mills discharged less water, and more discharge was treated, in 1978 than in 1973, these trends were especially dramatic among firms in the Northeast where controls were likely to have been most stringent. Finally, using the only direct evidence we have, it appears that the drop in discharge levels and the increasing amounts of treatment had a significant effect on the amount of BOD discharged to surface and ground water. In 1973 the pulp and paper mills in Wisconsin discharged an average of about 868,000 lbs/day; by 1982, despite increased levels of production, they discharged less than 10 percent of that. There is no doubt that industrial water use changed over the 25 years of record. Although the evidence is circumstantial, it appears that the CWA and the environmental ethic which spawned it played an important part in some aspects of the shifts.  相似文献   

17.
ABSTRACT The long-term effects of presently used and alternatively proposed water pricing policies were studied using some tools of operations research and economics. A discrete deterministic dynamic programming model was structured and operated to determine the optimal water supply capacity expansion paths for a hypothetical residential community with a given water pricing policy. The objective of the model was the maximization of future discounted consumers'surpluses plus producer's revenues net of the long-run cost of supply. State variables were the size of system capacity in MGD and stage variables were the times of feasible capacity increase in years. Demand curves, population sizes, and growth rates for various economic sectors of the community were assumed known, as well as short-run production and capital construction costs. Several policies, including constant unit rates, decreasing or increasing block rates and summer differential rates were tested. It was concluded that price plays a major role in the short-run allocation and long-run planning and conservation of water supplies. Conservational pricing policies were advocated as means of lowering the long-run cost of water, using the water price-demand function as a planning tool. Further research in these areas was recommended.  相似文献   

18.
Abstract: Residential water demand is a function of several factors, some of which are within the control of water utilities (e.g., price, water restrictions, rebate programs) and some of which are not (e.g., climate and weather, demographic characteristics). In this study of Aurora, Colorado, factors influencing residential water demand are reviewed during a turbulent drought period (2000‐2005). Findings expand the understanding of residential demand in at least three salient ways: first, by documenting that pricing and outdoor water restriction policies interact with each other ensuring that total water savings are not additive of each program operating independently; second, by showing that the effectiveness of pricing and restrictions policies varies among different classes of customers (i.e., low, middle, and high volume water users) and between predrought and drought periods; and third, in demonstrating that real‐time information about consumptive use (via the Water Smart Reader) helps customers reach water‐use targets.  相似文献   

19.
ABSTRACT: The paper outlines both the methods used and the results obtained in a study of the demand for municipal and industrial water for the Seattle region. The study was made as part of a regional water management study program, one objective of which is to “… identify, quantify, and set priorities for all current and future water uses …”. A basic concept in the study of municipal and industrial water use is that the demand for water is derived from the demand for output and the direct services that water provides. Principal characteristics of the study are: (1) Water use is studied by type - residential, commercial, industrial and public -with identification of factors affecting each; (2) Water demands are studied by season as well as on an annual basis; (3) Projections of future water use are tied directly to projections of economic change in the service area; and (4) The effects of alternative policies on water use are estimated. Water use levels are projected under alternative regional growth assumptions provided by the Puget Sound Governmental Conference, a regional planning agency. Thus, the water use planning is consistent with other regional planning programs in this respect. The results can be varied according to changes in specific factors affecting water use. The factors considered in the present study include: single-family residential lot size, distribution of population between single- and multi-family units, per capita water use by multi-family unit residents, and industrial and commercial water use per employee. An income elasticity of demand was estimated for single-family residential water use.  相似文献   

20.
The purpose of this study was to determine the degree of influence of various factors on municipal water consumption in Illinois. For the collection of basic data, questionnaires were sent to all public water works of incorporated towns. The questionnaire was designed to obtain information on factors which may have any effect on water use. The effects of the different parameters on water consumption were based on several correlation and regression combinations of predictands and predictors. It was found that in the Chicago region the percent of services and water used for commercial and industrial purposes and the age of the water works were the most important parameters influencing water consumption (gallons per capita per day) when pumpage is metered at the water works as well as at the customers. For the State, excluding the Chicago region, percent of public water use, persons per service, population and commercial and industrial water use were the most important parameters. It has been recommended that similar statistical analysis be conducted periodically to establish a trend or law of change from the influencing parameters.  相似文献   

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