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1.
Abstract: The diffuculty in understanding the listings of many available hydrologic models programmed in FORTRAN is a serious limitation to their verification and use. By expending more effort in creating clearly written computer programs, more information can be transferred to those interested in modeling hydrologic process. The use of simulation languages to produce more understandable program listings and increase the flow of informationg is recommended. An example is presented in which surface water runoff from storms on small rural watershedds is modeled.  相似文献   

2.
ABSTRACT: Many water systems in small cities and rural areas throughout the United States are facing water quality and supply problems. These problems are typically not the result of an unexpected event, but are the result of growth trends or decreasing water quality experienced over several years. This analysis uses the contingent valuation and benefit transfer methods to evaluate the willingness to pay for a rural water system in northcentral Montana. Both of the procedures resulted in similar values, ranging from about $4.05 to $7.50 per household per month for urban residents and $5.40 to $11.50 per household per month for rural residents, which is equal to 11 percent to 23 percent of current average water costs. The willingness to pay estimates do not include non-household water users. This analysis shows that useful planning information can be obtained from relatively inexpensive contingent valuation mail survey data and the benefit transfer method as long as the limitations of the data are understood. The willingness to pay for ensuring good quality rural water supplies in the future is likely to be low compared to the costs of extensive diversion and treatment systems. Willingness to pay estimates provide decision makers with information that can be used to avoid building a large water supply system that water users do not want to connect to because of high costs.  相似文献   

3.
ABSTRACT: The use of artificial recharge in Saskatchewan and the rest of Canada to improve rural community and farmstead domestic water supply has great potential. Approximately 75 percent of the people in rural Saskatchewan and 26 percent of all the people in Canada are dependent on ground water for their domestic water supply. Typically, this water is highly mineralized and is often unpalatable due to odor and taste. A source of readily available, high quality water to eliminate expensive chemical treatment of available water and long distance hauling would be of significant value to rural residents. Storage of high quality water in aquifers by injection through wells has been documented and has been shown to depend on the use of a surface water catchment system to provide the high quality water. Since air entrainment or formation clogging can occur in poorly operated recharge schemes, development of proper design and operation of recharging procedure is required. This can be accomplished by using an injection response computer model and a properly designed injection system. Small scale artificial recharge projects will provide a valuable commodity to rural water users and will promote sustainable and conjunctive use of surface and ground water resources.  相似文献   

4.
ABSTRACT The selection of an evaporator design must reflect the balancing of captial cost (primarily in heat exchanger surface and vessels) against operating cost (primarily steam cost) to achieve minimum cost. In a conjunctive plant the tendency is to select a low-capital cost, high-operating cost plant. In addition, it is advantageous to use a high-capacity plant which needs to be operated much less of the time than a plant which is sized just at the needed rate. For example, in the study of a possible system to satisfy a future increase of 450 MGD in water supply to New York Qty, a plant of 750 MGD capacity was selected as optimum. This plant, of the advanced VTE-MSF process type, would have a performance ratio of 9 lb product/1000 Btu as compared to 10-13 normally used for base-loaded plants. Steam would be supplied by a multi-unit dual-purpose nuclear power plant. The most economical type of energy supply would be “interruptible”; the steam would be used by a low pressure turbine to generate electricity during periods of peak electrical demand but would be available to the desalting plant at other times. The low pressure turbine would be available as spinning reserve during desalting plant operation. It is estimated that the desalting plant would have a load factor of 27 per cent over its life.  相似文献   

5.
The paper describes and analyses the 100 year development of water supply and sanitation and the lessons learnt in Porvoo, a municipality of 46,000 people on the southern coast of Finland. In urban areas the municipality‐owned utility has always dominated. Over 90 per cent of the investments for the recent wastewater treatment plant went into services, equipment and goods bought from the private sector through 12 tenders, all based on competition. In the neighbouring rural areas, recently merged with the city, there are nine consumer‐managed, non‐profit water cooperatives that buy water in bulk from the city water utility. Although the solutions are based on local conditions and subsidiarity, some more general principles are also highlighted and discussed. Past decisions inevitably also affect future development options.  相似文献   

6.
In the examination of the implementation of rural drinking water facilities, not enough attention has been paid to analyzing the socioeconomic and political relationships that affect the effective utilization of the facilities, particularly as these relate to women in rural society. This paper suggests that much of the difficulty in instituting the utilization of safe water supply sources has to do with the rather low economic status of women—the main water collectors. Poverty consigns women to long periods of work in activities or jobs that bring little reward. This makes it difficult to effectively digest the messages delivered by program staff and limits the extent of usage of the safe water facilities.  相似文献   

7.
ABSTRACT: Rapid population growth in the metropolitan area of Denver, Colorado, is causing conflicts over water use. Two cities, Thomton and Westminster, have begun condemnation proceedings against three irrigation companies to secure agricultural water rights for municipal use. This is the first condemnation proceeding against irrigation water rights for municipal use. Should the suit succeed, over 30,000 acres of presently irrigated land will lose its water supply. There are about four hundred landowners in the area; two hundred of these are commercial farmers, including truck, dairy and specialty farms. Total agricultural production amounts to about $8 million per year. About 561 jobs related to agriculture will disappear along with about $4 million in not income. Only 6.4 percent of the farmland along the Front Range is irrigated. Continued urban growth will put pressure on the water supply of much of this land. The interested parties of the region should cooperate to lessen the impact of urban growth on agricultural lands and water by forming a metropolitan water district. Such a district could share costs of development of additional municipal water and develop systems where municipalities would recycle waste water back to the irrigated lands.  相似文献   

8.
Full integration of projects and programmes for rural water supply and sanitation has yet to take place in most developing countries, thus contributing to a situation in which long-term success in the sector has been difficult to demonstrate. It is suggested that full integration in individual countries will require reorientation of project planning procedures, and the development of a community support programme (CSP) to provide backup to communities after project completion. Ultimately, full integration of projects and programmes is an iterative process, requiring the evaluation of past efforts in the field. Experience in the International Drinking Water Supply and Sanitation Decade (1981–90) has demonstrated that coverage alone — as the de facto indicator of success — is not sufficient (particularly in rural areas). The 1990s represent a fresh chance to modify indicators for success, and to go beyond coverage by integrating projects and programmes for rural water supply and sanitation.  相似文献   

9.
ABSTRACT: Adequate water supplies are critical to the maintenance of a community's health and economic well-being. Across the nation communities are struggling to meet an expanding demand for water from municipal, industrial, agricultural, recreation, water quality, and power generation users. As the demand grows and communities actively compete with one another for a limited water supply, states are being called upon to help solve the problem. One possible solution that is being used in many areas is the development and implementation of a water conservation program to stretch the limited supply as far as possible. using a mailed survey, state water conservation programs and some of the characteristics of the different programs were documented. Responses to the nationwide survey were obtained from all 50 states. The specific water conservation program elements on which information was received from the survey included laws and restricted use, community assistance, education, research, and other services. Recommendations for states developing or considering the development of a water conservation program are outlined.  相似文献   

10.
ABSTRACT: It is estimated that by about 1984 water demand in the District will nearly equal Nature's average annual replenishment of the supply and that, thereafter, unless means are developed to augment our in-District resources, water mining will be required on a grand scale. Sources of augmentation include: (1) reduction of wastes; (2) industrial recycling of previously-used water; (3) use of municipal sewage effluents; (4) desalination of brackish ground water; (5) aquifer recharge from all available, high-quality sources, particularly flood waters; and (6) importation of excess waters from such out-of-District sources as the lower courses of the Suwannee and Apalachicola Rivers. To achieve maximum beneficial uses of in-District sources a regional water and sewer authority is needed that can develop and transmit water from all available sources to the various county and city systems on a wholesale basis. It is envisioned that such a supply system would tie together all production sources, much as the electrical generation and supply systems are currently organized into regional electric power hookups. At least two bills are currently before the Florida Legislature to achieve these goals.  相似文献   

11.
ABSTRACT: Snowmelt runoff is a primary source of water supply in much of the Western United States. Multipurpose planning requires long-range forecasts and the accuracy of the forecasts has a significant effect on economic benefits. In an effort to increase the accuracy of snowrnelt runoff forecasts, selected practices in water supply forecasting were evaluated. These practices include 1) using multiple regression in developing forecasting models;2) using a model that was calibrated to make forecasts an April 1 for making forecasts at other times;3) using maximum snow water equivalent measurements in forecast equations; and 4) using weighted snow water equivalent measurements for making forecasts. The results of a case study indicate that forecasting accuracy is significantly affected by these practices. Goodness-of-fit statistics may not be indicative of the accuracy of forecasts when the prediction equations are used to make forecasts for dates other than that used in calibration. The use of maximum snow water equivalentmeasurements and weighted averages did not improve forecast accuracy.  相似文献   

12.
ABSTRACT: This study proposes that demand management through pricing policies can be used in conjunction with supply management to solve water supply problems. Economic principles are shown to apply to rural residential water use. A demand function for water was developed based on cross-sectional water use data collected in Kentucky. Price was found to be a significant determinant of the quantity of water demanded. A constant price elasticity of -0.92 was found. The demand function was used in a simulation analysis to determine reservoir capacity needed to supply water needs of a rural community. The simulation revealed that price can significantly affect required reservoir storage.  相似文献   

13.
There is still serious impact of inadequate and unsafe water supply on human health in many countries, and not only in developing ones. Waterborne diseases, such as diarrhoea, are responsible for more than 3 million deaths per year. Vector-borne diseases, such as malaria and schistosomiasis, are still rampant in the tropics causing severe human suffering and economic losses. Chemical hazards related to water are not only due to the presence of toxic substances, such as pesticides or heavy metals, but also due to excessive or deficient amounts of natural substances such as fluoride or iodine. Chemical risks have to be balanced with biological risks, and disinfection practices enforced without compromises. There is a long way to go, however, to fill the gaps in service coverage for water supply and sanitation, particularly in the rural areas and in the impoverished periurban areas. Various international programmes are in place or being initiated to this end.  相似文献   

14.
In Liberia, as in many developing countries, electrification of towns and cities throughout the country has long been a major development goal. However, fuel expenditures by the Liberian Electricity Corporation (LEC) for its rural public stations represent a major and growing burden on the financially hard-pressed utility. In this paper we evaluate the economics of supplying wood to rural electric power plants utilizing different sources of feedstock. We also evaluate the cost implications of differences in wood supply requirements based on the use of steam or gasifier technology, and from variation in plant utilization level.
The wood supply we consider as sources are: (1) retired rubber trees; (2) the harvesting of secondary-growth forest just before the land is returned to temporary cultivation; (3) the establishment of commercial short-rotation wood energy plantations; and (4) adding to the system of shifting agriculture the planting of fast-growing wood species. The results indicate that wood can probably be supplied under a wide range of supply and demand conditions for US$1.00–1.70 per GJ. We estimate that wood steam plants can generate power for about $0.09-0.14 per kWh and gasifier plants for $0.10-0.18 per kWh. These costs are well below the present cost of oil-based rural electric power generation in Liberia (about $0.20–0.27 per kWh).  相似文献   

15.
Summary In Kumaun Himalaya, India, 60 percent of the rural population is dependent on natural springs for water supply. The authors claim that substantial reductions in spring water discharges are due to losses in the indigenous oak forest coverage and its partial replacement by pine. Other factors, such as overall forest cover depletion and construction activities, combine to produce severe reductions in spring discharge rates.Drs Anil Singh and Ravindra Pande are members of academic staff at Kumaun University working in the Laboratory for Hydrological and Geomorphological Investigations in the Department of Geography.  相似文献   

16.
Our immense national water quality control program has been launched on a wholly empirical basis, much as our ancestors initiated early navigation improvements and flood control. Not only has there been no effort to determine the benefits of water quality control; the theoretical groundwork for optimization has not been developed. Three main national objectives for consideration are national economic efficiency, preserving and improving the national environment for man's use and development (conservation), and regional development. Although popular at present, the regional development objective is not particularly useful from an economic viewpoint. Efficiency objectives other than environmental can be evaluated but are apt to be minor. Other water quality benefits can be broken down appropriately into four main categories: (a) man's recreational environment; (b) man's home environment; (c) man's working environment; (d) intangibles related to scientific, historic, health and cultural values. In management of water quality, various technical relationships must be considered, particularly as to quantity of water needed for waste disposal, and relationship of this use to water supply withdrawals. Advanced waste treatment must be compared with other alternatives, not only of flow augmentation, but also technological process changes, distribution of effluents, and artificial river aeration.  相似文献   

17.
A method is presented for calculating allowable use of tracked vehicles on the US Army's Pinon Canyon Maneuver Site in southeastern Colorado. The first step in this process is to determine the sheet and rill erosion rate on each soil series using the revised Universal Soil Loss Equation. Soil series are then ranked according to their trainability (e g., ranked based on how much vegetative cover can be lost without exceeding soil loss tolerance) Maximum onetime surface use, allowable surface use per year, usable hectares per year, and tracked vehicle days per year can then be calculated Examples are given to illustrate how these values can be manipulated to assist land managers and military trainers to better plan and match training missions to available land. Also, short- and long-term monitoring schemes are presented that can be used to verify or adjust estimates of allowable use. The methods presented can be converted to determine allowable use of other types of activities that disturb the vegetation and expose the soil surface to the erosive forces of wind and water (e g, recreational and off-road vehicles).  相似文献   

18.
Rural industries and water pollution in China   总被引:10,自引:0,他引:10  
Water pollution from small rural industries is a serious problem throughout China. Over half of all river sections monitored for water quality are rated as being unsafe for human contact, and this pollution is estimated to cost several per cent of GDP. While China has some of the toughest environmental protection laws in the world, the implementation of these laws in rural areas is not effective. This paper explains the reasons for this implementation gap. It argues that the factors that have underpinned the economic success of rural industry are precisely the same factors that cause water pollution from rural industry to remain such a serious problem in China. This means that the control of rural water pollution is not simply a technical problem of designing a more appropriate governance system, or finding better policy instruments or more funding. Instead, solutions lie in changes in the model that underpins rural development in China.  相似文献   

19.
The demand for energy services is growing rapidly in developing countries. Low levels of energy efficiency in electric power supply and in energy use mean that the energy sector threatens to absorb an intolerably high share of available financial resources. Energy inefficiency also contributes to local and global environmental problems. A strategy of vigorously improving energy efficiency is thus a key element of a sustainable development path. Results reported in this paper show that there is considerable room for efficiency improvement in both existing and new capital stocks, but a much larger effort than presently underway is essential if the potential is to be realized. Assistance from the industrialized countries can play a major role in such an effort.  相似文献   

20.
ABSTRACT: The population in the Jemez y Sangre Water Planning Region of New Mexico has reached the point at which the demand for water exceeds available supplies, particularly when precipitation is below average, as has frequently occurred in recent years. The desire to develop a sustainable water supply that relies on renewable supplies in wet years and preserves the water in storage for times of drought motivated a diverse set of stakeholders in the region to participate in regional water planning. The planning effort culminated in development of the Jemez y Sangre Regional Water Plan, which was adopted by municipal and county governments in the region. The plan assesses and compares water supply and demand in the region and recommends alternatives for protecting and restoring the existing water supply and addressing the pending gap between supply and demand anticipated by the year 2060. To convey to decision makers the alternatives available to solve the future water shortage, option charts were developed to portray the amount of water that could be obtained or conserved through their implementation. The option charts show that the projected gap between supply and demand cannot be met through one alternative only, but will require a combination of alternatives.  相似文献   

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