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Showing papers on "Water supply published in 2001"


Journal ArticleDOI
TL;DR: Self-sustaining, decentralized approaches to making drinking water safe, including point-of-use chemical and solar disinfection, safe water storage, and behavioral change, have been widely field-tested and merit far greater priority for rapid implementation.
Abstract: Since 1990, the number of people without access to safe water sources has remained constant at approximately 1.1 billion, of whom approximately 2.2 million die of waterborne disease each year. In developing countries, population growth and migrations strain existing water and sanitary infrastructure and complicate planning and construction of new infrastructure. Providing safe water for all is a long-term goal; however, relying only on time- and resource-intensive centralized solutions such as piped, treated water will leave hundreds of millions of people without safe water far into the future. Self-sustaining, decentralized approaches to making drinking water safe, including point-of-use chemical and solar disinfection, safe water storage, and behavioral change, have been widely field-tested. These options target the most affected, enhance health, contribute to development and productivity, and merit far greater priority for rapid implementation.

296 citations


Journal ArticleDOI
11 May 2001-Science
TL;DR: In this paper, the authors recommend equitable market-oriented water pricing mechanisms, including realistic pricing, integrating watershed protection costs into water prices, and charging polluters for their effluents.
Abstract: Growing water scarcity and rapid declines in aquatic biodiversity indicate water policies are failing to protect life9s most vital resource. A major reason for growing water scarcity and freshwater ecosystem decline is that water is undervalued the world over. In this Policy Forum, the authors recommend equitable market-oriented mechanisms, including realistic pricing, integrating watershed protection costs into water prices, and charging polluters for their effluents. Science plays an essential role in providing information needed to make these mechanisms work effectively.

273 citations


Journal ArticleDOI
TL;DR: The water balance model (Aquacycle) developed in this study represents water flows through the urban water supply, stormwater, and wastewater systems and was tested using data from the Woden Valley urban catchment in Canberra, Australia and found able to satisfactorily replicate its water supply and wastewater flows.
Abstract: Current urban water management practices aim to remove stormwater and wastewater efficiently from urban areas. An alternative approach is to consider stormwater and wastewater as a potential resource substitute for a portion of the water imported via the reticulated supply system. A holistic view of urban water resources provides the framework for the evaluation of the demand for water supply, the availability of stormwater and wastewater, and the interactions between them. The water balance model (Aquacycle) developed in this study represents water flows through the urban water supply, stormwater, and wastewater systems. Its daily time step provides temporal distribution of the flows, and enables comparison of the different components of the urban water demand. Aquacycle was tested using data from the Woden Valley urban catchment in Canberra, Australia and found able to satisfactorily replicate its water supply, stormwater and wastewater flows. Crown Copyright  2001 Published by Elsevier Science Ltd. All rights reserved.

253 citations


Journal ArticleDOI
TL;DR: In this article, the authors propose a measure of economies of scope to assess the benefit associated with joint production of water for final customers and water losses, and several measures of returns to evaluate potential gains in exploiting technological flexibility of water networks.
Abstract: Network losses and returns are importantissues for water resource management, that are addressed in thispaper by modeling the structure of production for municipal waterutilities with two outputs: water sold to final customers andwater network losses. We propose a measure of economies of scopeto assess the benefit associated with joint production of waterfor final customers and water losses, and several measures ofreturns to evaluate potential gains in exploiting technologicalflexibility of water networks. We estimate the cost structureof water utilities using a GMM procedure with a Translog costfunction and panel data. Estimation results reveal a positivedegree of economies of scope, and short-run returns to productiondensity and returns to customer density that are not significantlydifferent from 1. Significant economies of scale indicate thatlocal communities may benefit from merging into water districts.

236 citations


Journal ArticleDOI
TL;DR: In this article, the authors present three classes of water vapour processing (AWVP) technology: cooling a surface below the dewpoint of the ambient air, concentrating water vapours through use of solid or liquid desiccants, or inducing and controlling convection in a tower structure.

183 citations


Journal ArticleDOI
TL;DR: In this paper, the authors provide a genealogy of concepts of efficiency and equity in water regulation over the past thirty years, prior to evaluating the implications for water consumers of one aspect of this process.
Abstract: Over the past three decades, the business of water supply in England and Wales has been gradually transforming from the supply of a service to citizens, to the sale of a commodity to customers. The paper provides a genealogy of concepts of efficiency and equity in water regulation over the past thirty years, prior to evaluating the implications for water consumers of one aspect of this process – the shift away from policies prioritizing inter- and intra-regional equalization (implying a principle of social equity) towards policies prioritizing economic efficiency (implying a principle of economic equity) in water charging. In closing, alternatives to the current arrangements for domestic consumers are proposed.

155 citations


Journal Article
TL;DR: A fundamental approach is to start at the field level, where water and rice interact, to look at the flow of water in rice fields and understand where reductions in water use can be achieved without impairing yield.
Abstract: Food security in Asia is challenged by increasing food demand and threatened by declining water availability. Rice is the most important staple in Asia, where it provides35-80% of total calorie intake (IRRI 1997). More than 75% of the rice supply comes from 79 million ha of irrigated land. Thus, Asia's present and future food security depends largely on the irrigated rice production system. However, the water-use efficiency of rice is low, and growing rice requires large amounts of water. In Asia, irrigated agriculture accounts for 90% of total diverted freshwater, and more than 50% of this isused to irrigate rice. Until recently, this amount of water has been taken for granted, but now the global "water crisis" threatens the sustainability of irrigated rice production. The available amount of water for irrigation is becoming scarce (Gleick 1993, Postel 1997). The reasons for this are diverse and location-specific, but include decreasing quality (chemical pollution, salinization), decreasing resources (e.g., falling groundwater tables, silting of reservoirs), and increased competition from other sectors such as urban and industrial users. Because of the increasing scarcity of water, the costs of its use and resource development are increasing as well. Therefore, farmers and researchers alike are looking for ways to decrease water use in rice production and increase its use efficiency. A fundamental approach is to start at the field level, where water and rice interact. For farmers with no control over the availability or distribution of water beyond their farm gates, thecrucial question to be addressed is "What are the options to cope with decreasing water supply (or the increasing costs of it) at the farm or field inlets?" To answer this question, we have to look at the flow of water in rice fields and understand where reductions in water use can be achieved without impairing yield (Fig. 1).

150 citations


Journal ArticleDOI
TL;DR: In this article, a case study in Adelaide, Australia shows that the genetic algorithm can be a powerful tool to assist in planning the rehabilitation of water pipes and demonstrates the use of the GA technique to find a near optimal schedule for the replacement of the water supply pipes.
Abstract: Like most other utilities, water authorities must manage many aging capital assets that are in varying degrees of deterioration; some of which are nearing the end of their useful lives. The annual funds available to the water authorities for the rehabilitation of these assets are only a small fraction of the total replacement cost of the infrastructure. It is important, therefore, that the available funds are used in the most effective manner. This paper demonstrates the use of the genetic algorithm technique to find a near optimal schedule for the replacement of the water supply pipes. The goal is to minimize the present value of capital, repair, and damage costs. A case study in Adelaide, Australia shows that the genetic algorithm can be a powerful tool to assist in planning the rehabilitation of water pipes.

134 citations


Journal ArticleDOI
TL;DR: In this article, the authors highlight the water scarcity and resource depletion in the North China Plain, the breadbasket of China, and suggest that the conventional wisdom of opening up new sources and economising on the use of resources may not be an optimal way to deal with water scarcity in the region.
Abstract: In this paper we highlight the water scarcity and resource depletion in the North China Plain, the ‘breadbasket’ of China. A projection of water demand in the region indicates a continuous aggravation in water deficit in the coming years. Analyses of countermeasures on the supply and demand side suggest that the conventional wisdom of ‘opening up new sources and economising on the use of resources’ may not be an optimal way to deal with water scarcity in the region. Importing water in the form of grain should be taken as an additional measure. This ‘virtual water import’ option needs to be incorporated into the current regional and national agricultural development strategy in which crop structural adjustment is at the core.

132 citations


Journal ArticleDOI
TL;DR: In this paper, a ground water modeling system was used to simulate the three-dimensional ground water flow and contaminant transport in the Tahta region of the Nile Valley Aquifer, and to predict the future concentrations of chemical fertilizer species.
Abstract: Chemical fertilizer use in Egypt has increased significantly since the construction of the Aswan High Dam in 1968. Increased applications of chemical fertilizers in irrigated lands are likely to create nonpoint contamination sources of chemical fertilizer species. This study was conducted to investigate the contamination of ground water by nitrogen and phosphorus chemical fertilizers, as well as the availability of ground water for irrigation and public water supply for the next century. Future concentrations of NO3, and PO3- in shallow and deep ground water in the Nile Valley were assessed under realizable rates of fertilizer application. A ground water modeling system (GMS) was used to simulate the three-dimensional ground water flow and contaminant transport in the Tahta region of the Nile Valley Aquifer, and to predict the future concentrations of chemical fertilizer species. Results of the transport simulation predict the occurrence of ground water contamination at shallow depths (30 m) due to the high rate and method of chemical fertilizer applications. Best management practices should be employed to control and reduce the nitrate leaching and future impact of phosphorus and potassium fertilizer applications. At the same time, new deeper wells should be constructed. In addition, the use of hand pumps, in zones close to croplands (15 m depth) must be avoided due to susceptibility to fertilizer contamination. Ground water from existing deep wells can be used as an alternative water supply. Furthermore, a ground water quality monitoring system should be established for early detection of ground water contamination and to determine progress of the fertilizer contaminant plume. A properly designed system should monitor nitrate and phosphate composition in observation and water supply wells.

132 citations


Journal ArticleDOI
TL;DR: In this article, a decision-support system for the evaluation and selection of potential non-conventional water resources supply; these include desalination of brackish and seawater, treated waste water, importation of water across boundaries and water harvesting.

01 Jan 2001
TL;DR: In this article, DFID's recently published water strategy paper, "Addressing the Water Crisis - Healthier and More Productive Lives for Poor People" was published to highlight the need for renewed efforts to improve the situation.
Abstract: There has been encouraging progress with access to safe drinking water and sanitation in both rural and urban areas since the United Nations Water Decade of the 1980s However, more than 1 billion people around the world still lack access to safe water supplies and more than 24 billion are without adequate sanitation A substantial majority of these people live in Asia where the lack of sanitation provision is particularly acute In Africa, over one third of the population still remains without access to safe water and sanitation, and many of these can only be served by groundwater The need for renewed efforts to improve the situation is recognised in DFID’s recently published water strategy paper – "Addressing the Water Crisis - Healthier and More Productive Lives for Poor People" The health benefits of safe water supply are only properly realised when programmes combine safe water supply with sanitation and the promotion of safe hygiene practice With increasing population, the pressure on land in all cities is becoming intense High levels of pollution are increasing the risk to groundwater from sanitation and drainage facilities These guidelines are an important contribution to risk assessment and the avoidance of the contamination of groundwater supplies from on-site sanitation They have been developed as part of a project funded by DFID through the water component of the Infrastructure and Urban Development Division’s Knowledge and Research Programme

Journal ArticleDOI
TL;DR: In this paper, the authors developed a flexible mechanism that produces a Pareto-efficient allocation for every possible flow volume in a river, based on stylized water demand relationships for India and Bangladesh.
Abstract: Increasing scarcity of water resources, and greatervariability in available water supply, are causingacute difficulties for allocation agreements amongusers of water bodies. One cause of controversy,especially for river waters, is the inability of mostallocation operations to accommodate variations inconditions. In this paper we develop a flexiblemechanism that produces a Pareto-efficient allocationfor every possible flow volume in a river. Extensionsto accommodate other kinds of variation, such as waterdemand, are feasible. The mechanism is demonstratedusing historical water flow data for the Ganges, basedon stylized water demand relationships for India andBangladesh. Quantitative comparison between fixed andvariable allocation suggests that variable allocationsubstantially outperforms fixed allocation, improvingregional welfare by at least ten percent.

Journal ArticleDOI
TL;DR: This approach will facilitate the accelerated and sustainable extension of environmentally responsible wastewater services to MENA's small communities and offers great potential for cost reduction, accommodates the necessary domestic water conservation efforts, reduces freshwater inputs in wastewater transportation thus eliminating unnecessary demand on freshwater, reduces associated environmental risks and increases wastewater reuse opportunities.

Journal ArticleDOI
TL;DR: The Safe Water System, which consists of point-of-use water treatment with sodium hypochlorite, safe storage, and behavior change techniques, was implemented within the already established WASEH infrastructure, using existing community organizations in combination with a social marketing approach that introduced affordable products.
Abstract: To prevent diarrheal diseases in western Kenya, CARE Kenya initiated the Water, Sanitation, and Education for Health (WASEH) Project in 1998. The project targets 72 farming and fishing communities with a total population of 43 000. Although the WASEH Project facilitated construction of shallow wells and pit latrines, the water quality still needed improvement. Consequently, in 2001, CARE implemented the Safe Water System (which consists of point-of-use water treatment with sodium hypochlorite, safe storage, and behavior change techniques) within the already established WASEH infrastructure, using existing community organizations in combination with a social marketing approach that introduced affordable products. The project has resulted in adoption rates of 33.5% for chemical water treatment and 18.5% for clay pots modified for safe water storage.

Journal ArticleDOI
01 Apr 2001
TL;DR: In this paper, the authors determine the optimal size of a water supply enterprise with the minimum average cost, using sample data from Japanese water supply organizations, and show that there are slight diseconomies of scale at the sample mean point.
Abstract: Within this analysis we determine the optimal size (that is, with the minimum average cost) of a water supply enterprise and reconsider the matter of scale economies, using sample data from Japanese water supply organizations. After surveying evidence from previous studies of scale economies in the water supply industry, we estimate cost functions with three different cost models: the log-linear, translog and translog with a hedonic function. We obtain the result that economies of network density do exist, but that there are slight diseconomies of scale at the sample mean point. The optimal size of a water supply organization would be one supplying a population of approximately 766,000 people. JEL classification: L95, L11

Book
01 Jan 2001
TL;DR: The challenge of urban water management Urban water as a part of integrated catchment management Interactions with the environment Infrastructure integration issues Emerging paradigms in water supply and sanitation Problems of developing countries Economic and financial aspects Social, institutional and regulatory issues Outlook for the 21st Century as mentioned in this paper.
Abstract: The challenge of urban water management Urban water as a part of integrated catchment management Interactions with the environment Infrastructure integration issues Emerging paradigms in water supply and sanitation Problems of developing countries Economic and financial aspects Social, institutional and regulatory issues Outlook for the 21st Century

Journal ArticleDOI
TL;DR: In this article, the authors discuss issues relating to the selection of proactive, planned adaptation measures for the near term (next decade) for the Canadian water sector, and propose a set of selection criteria.
Abstract: Climate change poses significant challenges for the Canadian water sector. This paper discusses issues relating to the selection of proactive, planned adaptation measures for the near term (next decade). A set of selection criteria is offered, and these are used in three cases to illustrate how stakeholders can identify measures appropriate for the near term. Cases include municipal water supply in the Grand River basin, Ontario; irrigation in southern Alberta; and commercial navigation on the Great Lakes. In all three cases, it is possible to identify adaptations to climate change that also represent appropriate responses to existing conditions; these should be pursued first.

Journal ArticleDOI
TL;DR: The current status of water reuse in Japan is summarized and dominant uses of reclaimed water are discussed, emphasizing non-potable urban applications such as toilet flushing, industrial reuse, and environmental water.

Journal ArticleDOI
TL;DR: Investigation within six selected German drinking water treatment plants in the course of the purification-process of surface water and in a subsequent drinking water supply gives a short survey about the prevalence and reduction of FLA in processing and supply of drinking water.

Journal ArticleDOI
TL;DR: In this article, the Union of most National Associations of Water Suppliers and Wastewater Services in Europe (Eureau) is involved in setting up international best practices and guidelines related to the reuse of treated wastewater.


Journal ArticleDOI
TL;DR: The study examines how residents living in a foothill community of the Valley of Mexico experience bodily distress associated with water scarcity and reveals some of the efforts made by people to address what they consider to be the social origins of their bodily distress.
Abstract: This article is an ethnographic analysis of what it means to "suffer from water." Using a critical medical anthropology approach, the study examines how residents living in a foothill community of the Valley of Mexico experience bodily distress associated with water scarcity. Data for the study come from participant-observation of domestic water use and community drinking water management as well as interviews with local civil and religious officials who monitor the water distribution system. While the community discourse on suffering from water does not correspond to biomedical categories of illness, it does speak to the physical and emotional hardships and the social conditions that limit residents' access to an adequate supply of domestic water. By taking a broad view of water-related suffering, the study reveals some of the efforts made by people to address what they consider to be the social origins of their bodily distress.

Journal ArticleDOI
TL;DR: Wang et al. as mentioned in this paper grouped possible solutions to water shortage, pollution, transferring water out of agriculture, and a surprisingly low water use efficiency into two categories: supply-side and demand-side solutions.

Journal ArticleDOI
C. J. Perry1
TL;DR: In this paper, the marginal price of water must be significant to bring supply and demand into balance, and the prices required to control demand are unlikely to be within the politically feasible range.
Abstract: Inadequate funding for maintenance of irrigation works and emerging shortages of water are prevalent. The use of water charges to generate resources for maintenance and to reduce demand is widely advocated. Examples from other utilities, and from the domestic/industrial sectors of water supply suggest the approach could be effective. In developing countries, the facilities required for measured and controlled delivery of irrigation are rarely in place, and would require a massive investment in physical, legal and administrative infrastructure. To be effective in curtailing demand, the marginal price of water must be significant. The price levels required to cover operation and maintenance (O&M) costs are too low to have a substantial impact on demand, much less to actually bring supply and demand into balance. On the other hand, the prices required to control demand are unlikely to be within the politically feasible range. Furthermore, water supplied is a proper measure of service in domestic and industrial uses. But in irrigation, and especially as the water resource itself becomes constrained, water consumption is the appropriate unit for water accounting. This is exceptionally difficult to measure. An alternative approach to cope with shortage would focus on assigning volumes to specific uses-effectively rationing water where demand exceeds supply. This approach has a number of potential benefits including simplicity, transparency, and the potential to tailor allocations specifically to hydrological situations, particularly where salinity is a problem. Data from Iran are presented to support these contentions.

Journal ArticleDOI
TL;DR: Water from tube-wells should be treated if used as drinking water in Matlab, Bangladesh, because results for some of the parameters were outside the accepted limits recommended by the World Health Organization for drinking water.
Abstract: Five tube-wells in Matlab, Bangladesh, were selected for analysis of selected biophysicochemical parameters. The results showed that all tube-well water samples contained zooplankton and bacteria. Results for some of the parameters were outside the accepted limits recommended by the World Health Organization for drinking water. It is concluded that water from tube-wells should be treated if used as drinking water.

Journal ArticleDOI
TL;DR: In this paper, a series of semi-structured in-depth interviews with key personnel from agencies responsible for emergency management and water supply; their jurisdictions ranged from urban to rural and local to regional.
Abstract: Unrelenting pressure on limited surface water supplies requires increasingly sophisticated water management approaches. Climate forecasts of seasonal precipitation and temperature are potentially useful, but the operational water management community currently underutilizes them. However, some agencies in Arizona took unprecedented advantage of forecasts for a potentially wet winter during the 1997–1998 El Nino event. This study investigates use of this information through a series of semi-structured in-depth interviews with key personnel from agencies responsible for emergency management and water supply; their jurisdictions ranged from urban to rural and local to regional. Interviews investigated information acquisition, interpretation, and incorporation into specific decisions and actions. While unprecedented actions were taken by some water management agencies and no agencies implemented inappropriate measures, some missed opportunities for more effective response, primarily through inaction. This study reveals a variety of technical factors and institutional characteristics affecting forecast use. Study findings emphasize the need for: (a) closer ongoing relationships between forecast producers and users, (b) increased institutional flexibility to exploit the increasing skill of seasonal climate forecasts, (c) demonstration projects of effective forecast use, and (d) a regional forum to facilitate information transfer between the hydro-climatic research community and operational water managers.

Journal ArticleDOI
TL;DR: The concept of HACCP (Hazard Analysis and Critical Control Points) was used to guarantee hygienically safe drinking water production to obtain a sustainable water catchment in the dune area of the Flemish west coast.

Journal ArticleDOI
TL;DR: The objective of this study was to assess whether use of irrigation seepage water for drinking results in less diarrhoea than directUse of irrigation water and how irrigation water management would impact on health.
Abstract: BACKGROUND In arid and semi-arid countries there are often large areas where groundwater is brackish and where people have to obtain water from irrigation canals for all uses, including domestic ones. An alternative to drawing drinking water directly from irrigation canals or village water reservoirs is to use the water that has seeped from the irrigation canals and irrigated fields and that has formed a small layer of fresh water on top of the brackish groundwater. The objective of this study was to assess whether use of irrigation seepage water for drinking results in less diarrhoea than direct use of irrigation water and how irrigation water management would impact on health. METHODS The study was undertaken in an irrigated area in the southern Punjab, Pakistan. Over a one-year period, drinking water sources used and diarrhoea episodes were recorded each day for all individuals of 200 households in 10 villages. Separate surveys were undertaken to collect information on hygiene behaviour, sanitary facilities, and socio-economic status. RESULTS Seepage water was of much better quality than surface water, but this did not translate into less diarrhoea. This could only be partially explained by the generally poor quality of water in the in-house storage vessels, reflecting considerable in-house contamination of drinking water. Risk factors for diarrhoea were absence of a water connection and water storage facility, lack of a toilet, low standard of hygiene, and low socio-economic status. The association between water quality and diarrhoea varied by the level of water availability and the presence or absence of a toilet. Among people having a high quantity of water available and a toilet, the incidence rate of diarrhoea was higher when surface water was used for drinking than when seepage water was used (relative risk 1.68; 95% CI 1.31–2.15). For people with less water available the direction of the association between water quality and diarrhoea was different (relative risk 0.80; 95% CI 0.69–0.93). This indicates that good quality drinking water provides additional health benefits only when sufficient quantities of water and a toilet are available. In a multivariate analysis no association was found between water quality and diarrhoea but there was a significant effect of water quantity on diarrhoea which was to a large extent mediated through sanitation and hygiene behaviour. CONCLUSIONS Increasing the availability of water in the house by having a household connection and a storage facility is the most important factor associated with reduced diarrhoea in this area. Safe use of canal irrigation water seems possible if households can pump seepage water to a large storage tank in their house and have a continuous water supply for sanitation and hygiene. Irrigation water management clearly has an impact on health and bridging the gap between the irrigation and drinking water supply sectors could provide important health benefits by taking into account the domestic water availability when managing irrigation water.

Journal ArticleDOI
Peter Newman1
TL;DR: The 'big pipes in, big pipes out' approach to urban water management was developed in the 19th century for a particular linear urban form but it has never worked in poor cities and an alternative which uses new small-scale technology and is more community-based is suggested.