Showing papers on "Water supply published in 1984"

WHO guidelines for drinking-water quality.

Abstract: In soil, fertilizers containing inorganic nitrogen and wastes containing organic nitrogen are first decomposed to give ammonia, which is then oxidized to nitrite and nitrate. The nitrate is taken up by plants during their growth and used in the synthesis of organic nitrogenous compounds. Surplus nitrate readily moves with groundwater (2, 3). Under aerobic conditions, it percolates in large quantities into the aquifer because of the small extent to which degradation or denitrification occurs. Under anaerobic conditions, nitrate may be denitrified or degraded almost completely to nitrogen. The presence of high or low water tables, the amount of rainwater, the presence of other organic material, and other physicochemical properties are also important in determining the fate of nitrate in soil ( 4). In surface water, nitrification and denitrification may also occur, depending on the temperature and pH. The uptake of nitrate by plants, however, is responsible for most of the nitrate reduction in surface water. Nitrogen compounds are formed in the air by lightning or discharged into it from industrial processes, motor vehicles, and intensive agriculture. Nitrate is present in air primarily as nitric acid and inorganic aerosols, as well as nitrate radicals and organic gases or aerosols. These are removed by wet and dry deposition.

Economic Considerations of Deficit Irrigation

Abstract: The factors related to potential yields of crops are briefly described. The most important are water, fertility, and available energy as measured by the evaporative potential. Mathematical yield models are presented relating crop evapotranspiration and total water available to relative yields. Data relative to irrigation amounts, rainfall, type of irrigation, water costs, costs of applying water, total crop production expenditures, and the range of crop incomes for various California crops are used to determine how various factors relate to the economics of deficit irrigation. The principal considerations in evaluating profit include whether land or water are limiting resources, the value of crop production based on yield and price, the contribution of rainfall to the crop water supply, the costs of irrigation water and its relationship to total crop production costs. Other considerations, such as leaching requirements and the need to promote uniform maturing of a crop, are briefly described. A minimum da...

Saving Water in a Desert City

Abstract: The lessons learned from a political battle in Tucson, Arizona, over water conservation derive from a policy analysis started by the city in 1976 when per capita water had dropped 30% below the 205-gallon per capita peak reached in 1973-74. This case history relates the role of the four P's (preachments, prices, politics, and practices) in a way water is perceived and used. Tucson's experience suggests better ways to estimate demand under block rates and recommends a more rational price structure for municipal water. It also shows how water-use issues interact with and influence municipal growth and development. Among the conclusions from public surveys are that conservation does not always benefit the environment, that increasing block rates do not always reflect costs, that the public responds best to voluntary conservation, and that urban residents in arid regions are not more wasteful. 206 references, 11 figures, 25 tables.

Microbiology of Potable Water

Abstract: Publisher Summary This chapter describes the microbiology of potable water from a historical as well as an ecological perspective The historical perspective reacquaints with the insights and endeavors of investigators who preceded researchers in the quest for protection and understanding of the microbial quality of water The ecological perspective is reviewed as it applies to applied ecology, which attempts to explain why and how organisms move from one ecosystem to another and the mechanisms which prevent or enhance such movement “Ecosystem” is defined as each unique environment, ie, source waters, treatment plants, or distribution systems Once this view is adopted, the subject of potable water microbiology becomes a series of discrete yet intimately linked parts One can imagine the source water, treatment plants, and the distribution system as separate ecosystems linked together by the continuous flow of water from its origin to the consumer This chapter identifies the critical linkages and how they function in each of these systems It endeavors to report not only the state of knowledge of microbiology, but also the importance of chemistry and engineering aspects, in each compartment of the potable water system

Water supply and health in developing countries: selective primary health care revisited.

Abstract: The inclusion of water supply and sanitation programs as a component of primary health care (PHC) has been questioned on the basis of calculations of the costs of these programs per infant death averted. In this paper the procedures used in these cost-effectiveness calculations are examined and found to be wanting. The calculations are misleading since gross rather than net costs have been used, and the health impact of these programs underestimated. It is also shown that the methodology used is biased against water supply and sanitation and other programs with multiple outputs. The time constraints facing mothers in implementing PHC programs, as well as the contribution of improved water supplies in alleviating these constraints are outlined. Data are presented to show that, if poor women in developing countries were to choose the mix of activities to be included in PHC programs, improved water supplies would frequently constitute part of that mix.

Water and the search for public health in London in the eighteenth and nineteenth centuries

Abstract: THE history of water supplies in England is a poorly documented subject. Although various accounts of the history of water technology, and learned articles on the political and administrative aspects of water supply have been written, the history of water in relation to public health remains largely unexplored. As this is, especially concerning the nineteenth century, a voluminous subject, the present paper attempts no more than a broad survey of the process by which water came to be recognized as a vital element in public health, of the gradual discovery and application of criteria for water purity, and of the means by which supplies satisfactory in quantity and quality were obtained. The roots of the modern concern with environment and its effect on health lie in the eighteenth century, and in this period the first indications of interest in the quality and physical effects of water are found. Health and cleanliness were treated as personal matters in the eighteenth and earlier nineteenth centuries: in the first parliamentary inquiry into water quality in 1828 there is little evidence of any wider concern with the health of the general population. It was only in the later 1 830s and 1840s that the idea of public health in its widest, or modern, sense began to gain currency, and only in the second half of the nineteenth century that the term came to have, for certain social elements, a further dimension of public morality as well. It is against this background of movement from an individual to a social concern that the development of modern standards of water services must be viewed. The evolution of the public health idea during this period is reflected in the nature and quantity of primary sources. These are sparse for the eighteenth century, but plentiful by the second half of the nineteenth. The sources for the latter period are also more familiar, and therefore have been treated more cavalierly in this paper: the intention has been more to illuminate less familiar aspects of the water question than to present a definitive history. The geographical scope of this account has been limited to London, partly for convenience, but also because the experience of the capital was crucial in influencing the development of medical and legislative concern with water.

Toxins of freshwater cyanobacteria

Abstract: Animal deaths after drinking water containing toxic cyanobacteria have been known for over a century. Poisonings occur annually and the fate of the toxins in natural and man-made waters is unknown. This article reviews the formation, properties and effects of freshwater cyanobacterial toxins.

Water for the Dyehouse: Supply, Consumption, Recovery and Disposal

Abstract: Factors which account for the almost universal choice of water as a medium for textile dyeing processes are outlined. Many of the dominant trends in the development of improved equipment and processes during the last decade have been associated with the control and treatment of this essential resource. Typical examples include the strong links between water conservation and most of the effective ways of saving energy, improvements in effluent treatment plants to minimise the impact of water-borne contaminants on the environment, exploitation of the possibilities for reuse of process water or treated effluent in further processing, as well as the direct objective of holding in check the rising contribution of water supply and effluent treatment to limit overall costs. This broad expanse of water, pure and impure, is surveyed from the viewpoint of the textile dye user, since, by virtue of the physical and chemical properties of textile dyes, he is also invariably a continual user of water.

Water supply method and system

Abstract: A system for supplying water from a main to a plurality of points of utilisation includes a manifold 13, a branch pipe 10 connecting the manifold inlet 12 to the water main, and a plurality of pipes 17 connecting the manifold outlets 15 to the points of utilisation of the water. The manifold 13 is disposed within a covered access shaft and each manifold outlet 15 is provided with an individual stop valve 16 to turn on and off the water supply to each point of utilisation.

Removal of enteric viruses from surface water at eight waterworks in The Netherlands.

Abstract: Eight waterworks in The Netherlands, which use surface water as their raw water source, were sampled repeatedly between November 1978 and June 1981 At five waterworks , 30 of 45 samples of raw water contained viruses Of 55 samples of partially purified water, 11 were virus positive, including 8 after coagulation, sedimentation, and rapid sand filtration, 2 after storage, coagulation, sedimentation, transport chlorination, and rapid sand filtration, and 1 after storage in open reservoirs for 5 months No viruses were detected in 100 samples of drinking water of 500 liters each from six waterworks Most isolated viruses were typed, and a great variety of human enteroviruses were found, reflecting both pollution of raw water sources with sewage and vaccination with oral polio vaccine in neighboring countries

The evaluation of eutrophication impact in public water supply reservoirs in East Anglia

Abstract: Etude comparative de l'evolution de la qualite de l'eau de 12 reservoirs: causes mecanismes, evolution et effets de l'eutrophisation sur l'adduction d'eau

Enhanced oil recovery water requirements

Abstract: Water requirements for enhanced oil recovery (EOR) are thoroughly evaluated using publicly available information, data from actual field applications and information provided by knowledgeable EOR technologists in fourteen major oil companies. Water quanity and quality requirements are estimated for individual EOR processes (steam drive,in situ combustion and carbon dioxide, micellar-polymer, polymer and caustic flooding) in those states and specific geographical locations where these processes will likely play major roles in future petroleum production by the year 2000. The estimated quantity requirements represent thetotal water needed from all sources, e.g. aquifers, lakes and produced water. A reduction in these quantities can be achieved by reinjecting all of the produced water potentially available for recyle, e.g. some is lost in oil and water separation and water treatment processes, in the oil recovery method. For injection water quality requirements, it is noted that not all of the water used for EOR needs to be fresh. The use oftreated produced water can significantly reduce the quantities of fresh water that would be sought from other sources. Although no major EOR project to date has been abandoned because of water supply problems, competing regional uses for water, drought situations, and scarcity of high quality, e.g. low total dissolved solids, surface water and ground water could be impediments to certain projects in the near future.

Water Conservation and Capacity Expansion

Abstract: AS water becomes relatively more scarce and as the cost of developing new sources of water increases, projects designed to reduce the quantities of water consumed (i.e, demand management projects) become more attractive alternatives to supply augmentation projects. A framework is presented that allows planners of water supply systems to make efficient use of water resources by explicitly considering the management of the demand for water as a supplement to traditional supply augmentation projects. The framework includes a dynamic programming algorithm to determine the optimal combination of supply augmentation and demand management projects. Two optimization criteria are considered: (1) Minimization of the present value of the cost of implementing the projects; and (2) minimization of the expected value of the costs to cope with emergencies in the supply of water. The tradeoffs between the two objectives are examined through the development of the set of noninferior solutions using the Non‐Inferior Set Es...

Water supply in the United States

Abstract: TO its excellent series of pamphlets on water supply the United States Geological Survey has just added three papers, one (No. 270) descriptive of the hydrographical features of the Great Basin, an immense tract of country 208,000 square miles in area (just as large as Germany), and extending over parts of the States of Utah, Nevada, Idaho, Oregon, and California; the other two, practical manuals entitled, respectively, “Underground Waters” (Paper No. 258) and “Well-Drilling Methods” (Paper No. 257).

Effects of Acid Rain on Water Supplies in the Northeast

Abstract: Results of the first study concerning the impact of acid precipitation on drinking water are reported in terms of health effects in humans as measured by US Environmental Protection Agency maximum contaminant levels. The study focused on sampling surface water and ground water supplies in the New England states but also included other sites in the Northeast and the Appalachians. No adverse effects on human health were demonstrated, although the highly corrosive nature of New England waters may be at least partly attributable to acidic deposition in poorly buffered watersheds and aquifers.

Crop-water production functions: economic implications for colorado

Abstract: Crop-water production functions are estimated for corn, soybeans, and sugar beets grown in Colorado with two irrigation efficiency levels. Farmers with high-cost water can conserve water and increase profits by applying profit- rather than yield-maximizing water quantities if crop prices are low. Application efficiencies. have a greater effect on profits at high water costs, but a greater effect on water use at low water costs.. Water supply restrictionsof 10 percent or less have a small effect on farm profits. Farmers should .maintain full Acreage in production and reduce water, applications per acre.for maximum profits under water supply restrictions of 20 percent or less.

Water Today and Tomorrow

Abstract: These conference proceedings include 87 papers dealing with irrigation-related topics concerning water supplies, water quality, legal and social infrastructure, irrigation projects and on-farm concerns. Topics include: irrigation project planning, operations, maintenance and post analysis; irrigating with high saline waters and waste water; drainage schemes for the San Joaquin Valley; analysis of aquifer systems; surface irrigation modeling; evaluation and management of farm irrigation systems and equipment; crop water requirements; watershed management and surface runoff modeling; innovations in flood control management; social and legal implications of water development; weather modification; assessing modern data bases on water resource information; and water quality management with conjunctive use of diversified water supplies.

Acid precipitation and drinking water supplies

Abstract: Three areas of concern about the effect of acid precipitation on drinking water supplies are evaluated - the increased levels of heavy metals in raw water, biological imbalances in water supplies, and increased corrosivity of delivered water. Although two thirds of the US water supplies are corrosive, the extent to which this corrosivity is related to acid precipitation is unknown. Shallow wells in the Adirondack Mountains that are directly recharged by rainfall are exceptionally corrosive. Potential management practices are suggested.

An Attempt to Reduce Nitrate Content in Ground Water Used for Municipal Water Supply by Changing Agricultural Practices

Abstract: The heavy use of manure and fertilizers has in some parts of Sweden resulted in unacceptable concentrations of nitrate in ground water used for private and municipal water supply. In Halland for example, several of the municipal water supplies have nitrate concentrations close to 50 mg/I. Either anionic exchange or mixing with water with less nitrate are used to reduce the nitrate content in the distributed water. However, some wells have been abandoned because of high nitrate concentrations. In this study an attempt is made to reduce the nitrogen contamination of the ground water at the source. In well recharge areas the agricultural practices are investigated and, if necessary, alterations are proposed to the farmer in order to decrease the nitrogen leaching from the soil profile. The effect of these improvements is continuously studied in soil and ground water. An action plan is proposed for water supplies with dominating arable land in the recharge area.

Drought-related impacts on municipal and major self-supplied industrial water withdrawals in Tennessee -- Part A

Abstract: During 1981, 463 public community water facilities supplied water to approximately 3,814,000 people or 83% of the 1980 population of Tennessee. Total water supplied was 566.1 million gallons per day of which 346.8 millions gallons per day or 61% was from surface-water sources and 219.3 million gallons per day or 39% was from ground water. Ground water was used for public supply statewide, however, it was the sole source of public supply west of the Tennessee River basin. Of the 219.3 million gallons per day used statewide, 164.0 million gallons per day or 75% was used in West Tennessee. Statewide 129 companies indicated a self-supplied water use of 0.1 million gallons per day or more. The total self-supplied water used by these companies was 1,106.7 million gallons per day of which 1,006.8 million gallons per day or 91% was surface water while 99.9 million gallons per day or 9% was ground water. Analysis of the study results and findings indicates that many communities in Tennessee do experience occasional water-supply, quantity-related shortages. Some type of problem was reported at 107 of the public water suppliers and 23 of the self-supplied commercial and industrial water users. Altogether, 172 problems were reported whichmore » could be grouped into 18 types. Occasional turbidity, inadequate storage capacity, inadequate water supply during droughts, and excessive water losses due to leaks in distribution lines accounted for 110 or 64% of the problems reported. Twenty-five or 15% of the problems reported were related to water shortage. Only two large, self-supplied industries reported experiencing water shortage during periods of droughts. Both were located in the Tennessee River basin. No problems were reported by industry in the West Tennessee area or in the Cumberland River basin.« less

Canadian Water Management: A One Armed Giant

Abstract: The need for increased emphasis on water demand management in Canada is outlined in the paper, as a complementary strategy to the traditional water supply management approaches. The general water supply management approaches tend to unvalue or undervalue water resources. Thus, water is seen as a limitless resource and water systems are wasteful rather than economically efficient. The principal resource allocation means in Western economies, the price system, is then examined to assess its usefulness in the water resource field. Examples are provided of areas in which demand-based approaches would be useful adjuncts to current approaches. Finally, it is also argued that demand management is a pro-development strategy, in contrast to some perceptions that incorporation of demand management strategies would inhibit development.

Monitoring device for water supply equipment

Abstract: PURPOSE:To effectively monitor the leakage out of a water supply equipment by providing a water leakage detection means in the water supply equipment CONSTITUTION:A water service meter 11 having a transmitter is used as a water supply volume detection means that outputs a detection pulse P1 at every predetermined water supply volume of the public water service into a water reservoir tank 3 An alarm device 12 is a water detection means, and consists of a microcomputer control section, ten keys for setting a standard water consumption volume and an indicator panel The alarm device 12 counts the pulse P1 from th meter 11 and compares it with the reference water consumption, and if the reference consumption is exceeded, the indicator panel lets out an alarm to tell the leakage In this manner, the water leakage in the water supply equipment in a building, etc due to a failure of a flash valve in the toilet or neglect to turn off the tap, etc can effectively be detected

Compatibility of Multiple Uses: Potable Water Supplies and Fisheries

Abstract: Development of multipurpose impoundments which include water supply and fisheries uses has resulted in a controversy between agencies responsible for water supply quality and those responsible for fisheries management. A survey of 16 states indicated that this controversy exists in many geographical areas of the United States. The focal point of the issue is primarily related to the widespread practice of leaving standing timber in the impoundment to provide useable habitat by certain game fishes. A review of the literature indicates that such practices contribute little to degradation of water quality. Lake morphology, drainage basin land use practices, and natural seasonal variation in climates contribute most significantly to frequently encountered water quality problems associated with drinking water supplies.

Water Supply for Power in Texas‐Gulf Region

Abstract: Most water-energy assessments have considered only a few water supply types and conservation technologies. Yet utilities are not only developing traditional surface sources, but are also using ground and waste water and buying water rights from irrigators. A linear program is developed that incorporates: (1) Supply curves for several water sources that reflect institutional constraints; and (2) water demand curves based on the cost of alternative power plant cooling methods. The purpose of the model is to aid the Electric Power Research Institute in strategic planning on water availability issues. For the Texas-Gulf region in the year 2000, it is found that the high cost of dry or mixed wet/dry cooling is unjustified unless: (1) New technologies lower the incremental cost of wet/dry cooling by more than 80%; or (2) unforeseen institutional restrictions prevent utilities from securing economic surface and ground water supplies. This conclusion contradicts previous studies which projected serious water-energy conflicts for the region.