Showing papers on "Water supply published in 1999"

The Impact and Sustainability of Community Water Supply and Sanitation Programmes in Developing Countries

Abstract: Sound strategies for community water supply and sanitation programmes in developing countries should be based on a clear understanding of the existing problems, the beneficial impacts achievable, and the factors which determine sustainability. The impacts of many water and sanitation programmes are limited, and many systems break down and are abandoned prematurely. Only limited impacts are achievable in the short term without greatly increased investment. Sustainability, in the sense of continued delivery and uptake of services, is threatened by numerous attitudinal, institutional and economic factors, and community participation approaches alone are no guarantee of success. The key to sustainability is that all stakeholders involved in consumption/use, maintenance, cost recovery, and continuing support perceive it in their best interests to deliver high quality services. The paper proposes new sets of programme aims and objectives in relation to impact and sustainability, which can be used in programme design, monitoring and evaluation. It also makes longer term recommendations to external support agencies.

Water pollution and human health in China.

Abstract: China's extraordinary economic growth, industrialization, and urbanization, coupled with inadequate investment in basic water supply and treatment infrastructure, have resulted in widespread water ...

A new modeling approach for water resources policy analysis

Abstract: Water resources policy analysis deals with the protection of people from the harmful effects of water and assurance of a consistent, adequate supply of usable water. Population and regulatory pressures, political and economic instabilities, and climatic variations can all be expected to further stress water supply resources. Developing policy for managing water systems for human needs in such an environment is difficult, slow, and very costly. The approach to water resources policy analysis developed in this paper is that of the rational decision maker who lays out goals and uses logical processes to explore the best way to reach those goals. The decision maker may be an individual or a group. The emphasis in this paper is on how water resources decisions ought to be analyzed and made. In establishing this framework we are proposing integration of object-oriented modeling approach with systems analysis. Our concern here is with how the water policy analysis process should be structured to best address a policy choice, and with the object- oriented model that will aid understanding and prediction. The proposed approach is illustrated in the paper by the case study of water resources policy analysis for Egypt.

Formal and informal markets for water : institutions, performance, and constraints

Abstract: Water markets either formal or informal can be an efficient method for reallocating scarce water supplies. At the same time certain constraints can raise the transaction costs of trading water. This paper reviews the conditions necessary to establish successful water markets, identifies potential problems, and offers mitigating strategies. It also uses examples of several informal and formal water markets already in operation to illustrate these problems and the solutions to them. This article proposes that countries facing water shortages under their current water pricing systems consider water marketing as a way to reallocate water resources. Authors illustrate the importance of understanding a country's institutional framework before embarking on a comprehensive overhaul of water policies and review the conditions required for effective water markets. Recent studies of formal and informal markets highlight the gains from the efficient allocation of water as well as the constraints that raise the transaction costs of trading water. As authors point out, water markets can provide the appropriate economic incentives to improve the efficiency of water use and encourage the reallocation of water to higher-valued uses without encountering the traditional opposition of existing water users.

Municipal Water Supply and Sewage Treatment: Costs, Prices, and Distortions

Abstract: Municipal water supply and sewage treatment utilities in Ontario, Canada, are studied in order to establish their costs of supply and evaluate their pricing practices. Prices charged to residential and commercial customers are found to be only one-third and one-sixth of the estimated marginal cost for water supply and sewage treatment, respectively. For example, the average price to residential customers is $0.32m[superscript 3], while the estimated marginal cost is $0.87/m[superscript 3]. The estimated cost parameters are combined with estimated residential and nonresidential demands functions in order to calculate approximate welfare losses that arise from overconsumption.

Relative regional vulnerability of water resources to climate change.

Abstract: Changes in global climate may alter hydrologic conditions and have a variety of effects on human settlements and ecological systems. The effects include changes in water supply and quality for domestic, irrigation, recreational, commercial, and industrial uses; in instream flows that support aquatic ecosystems, recreation uses, hydropower, navigation, and wastewater assimilation; in wetland extent and productivity that support fish, wildlife, and wastewater assimilation; and in the frequency and severity of floods. Watersheds where water resources are stressed under current climate are most likely to be vulnerable to changes in mean climate and extreme events. This study identified key aspects of water supply and use that could be adversely affected by climate change, developed measures and criteria useful for assessing the vulnerability of regional water resources and water dependent resources to climate change, developed a regional database of water sensitive variables consistent with the vulnerability measures, and applied the criteria in a regional study of the vulnerability of U.S. water resources. Key findings highlight the vulnerability of consumptive uses in the western and, in particular, the southwestern United States. However, southern United States watersheds are relatively more vulnerable to changes in water quality, flooding, and other instream uses.

Multiple uses of water in irrigated areas: a case study from Sri Lanka

Abstract: Water is being transferred out of agriculture to meet the g rowing demand in other areas, often without an agreement of or compensation to farmers with irrigated land and water rights. This paper argues that to ensure efficient, equitable, and sustainable water use, to reduce poverty and improve the well-being of the community, irrigation and water resources policies need to take into account all uses and users of water within the irrigation system. The multiple uses of water in the Kirindi Oya irrigation system are examined in this paper. An interdisciplinary group of scientists has investigated a number of areas including water accounting, water quality, household water use, the valuing of water for alternative uses, and the complementarities, competition, and conflicts among uses and users. Among the various management issues and the problem areas identified, the allocation of irrigation water particularly in periods of scarcity, is perhaps the most critical decision and one that has provoked considerable conflicts in the past. The most appropriate water level to be maintained in the tanks is another critical decision, with evidence to suggest that improved management of the tank systems in the wet season could lead to savings of water and expansion of irrigated area in the dry season. Finally, the study highlights the importance of water quality not only for domestic use but also for fishing and wildlife.

Indicators of Impacts of Global Climate Change on U.S. Water Resources

Abstract: Environmental and socioeconomic indicators are selected to study the impacts of global warming on the water resources of the United States. One of the indicators, regional reservoir storage vulnerability, is a particularly useful index summarizing the effectiveness of regional water supply systems to meet demands. A comparison of indicator tabulation and evaluation methods finds that reporting an indicator as a fraction of its stress threshold is most effective. Indicator display methods are compared, and the star diagram proves most effective as a visual aggregation technique. Indicators and evaluation methods are applied to the present climate and to one possible climate change scenario assuming economic growth. It is apparent that the primary impacts of global warming occur in the western U.S. and include (1) fewer relative stresses on hydroelectric systems due to an increase in energy supply from other sources, and (2) more stresses on available water resources due to increases in total withdrawals and, in some cases, decreases in flows. The writers believe that the wise indicator display methods, mathematical aggregation of indicators into indices may be unnecessary.

Household Water Resources and Rural Productivity in Sub-Saharan Africa: A Review of the Evidence

Abstract: The benefits and costs of providing a safe, convenient, and reliable water supply to households in the developing world have been the subject of a vast and wide-ranging research effort for at least four decades. Despite the quantity of studies carried out, relatively little is known about a number of key aspects of household water use. In particular, the productivity cost to households of having an inadequate water supply, measured in terms of the quantity and quality of labor lost as a result, has rarely been examined carefully. There is also relatively little known about water use in rural areas, as most research has focused on the developing world's rapidly expanding cities. Among the regions of the world, both of these research gaps are most acute for sub-Saharan Africa, the region whose population is the most rural and has the least access to an improved water supply. This paper reviews and summarizes the results of studies of household water use in rural areas of sub-Saharan Africa that offer clues to the effects of household water resources on rural productivity. Findings are presented on the extent of household access to safe water supplies, household water use, the costs of water-related diseases, the time costs of collecting water from distance sources, and the costs and benefits of interventions to improve household water supplies. Most studies indicate that household water use in sub-Saharan Africa averages only about 10 liters/person/day, far less than is needed for proper hygiene practices. Water-related diseases account for between 10 percent and 12 percent of all morbidity and mortality in sub-Saharan Africa. Households (and primarily women) spend an average of 134 minutes/day collecting water, and time saved by bringing water supplies closer to households is likely to dominate estimates of the benefits of improving rural water supplies. Data on the current and future costs of water-related diseases; the opportunity cost of time spent collecting water and lost to sickness or caring for the sick; and what kinds of water supply, sanitation, and hygiene interventions, in what sequence, produce the greatest health benefits are poor, and further research on these issues is needed.

Policy implications of climate forecasts for water resources management in the Pacific Northwest

Abstract: The Columbia River Basin management system suffers from conflicts over water use and allocation, and vulnerability to climate variability that disrupt hydropower, fisheries, irrigation, water supply, and other vital activities Climate forecasts have the potential to improve water resource management in this system supporting management decisions that decrease its vulnerability to droughts, floods, and other crises related to climate variability This study shows that despite the potential utility, managers do not use climate forecasts except for background information The barriers to managers' use of climate forecasts include low forecast skill, lack of interpretation and demonstrated applications, low geographic resolution, inadequate links to climate variability related impacts, and institutional aversion to incorporating new tools into decision making To realize the potential of climate forecasts for water resources management, we recommend strategies that include technical improvements to the forecast products, and joint efforts between forecast producers and the management community to develop and demonstrate climate forecast applications through reciprocal and iterative education

The Financing of Hydropower, Irrigation and Water Supply Infrastructure in Developing Countries

Abstract: A companion paper in the previous issue of this journal (Briscoe, 1999) describes the changing face of infrastructure financing in developing countries. This paper deals with the financing of major infrastructure in the water-related sectors-hydropower, water supply and sanitation, irrigation, and overall water resources management (including the environment). The overall level of investment in water-related infrastructure in developing countries is estimated to be of the order of $65 billion annually, with the respective shares about $15 billion for hydro, $25 billion for water and sanitation and $25 billion for irrigation and drainage. About 90% of this investment comes from domestic sources, primarily from the public sector. Water-related infrastructure accounts for a large chunk-about 15%-of all government spending. This heavy dependence on the public sector means that the global 'winds of change' in the respective roles of government and the private sector have major implications for the financing an...

Hedging Rule Optimisation for Water Supply Reservoirs System

Abstract: This article presents a methodology for planning a modelfor the operation of a drinking water reservoir. The hedging ruledistributes deficits over a longer period of time by rationingthe supply of water and it makes the system sustainablewith a marginal reduction in supply. A methodology isdeveloped and demonstrated through a case study withthe Chennai city (India) water supply system which isa water shortage system requiring an efficient use ofwater. It is aimed at improving the reservoiroperation performance through the simulation–optimisationprocedure with the application of the hedging rule, whichis a more appropriate rule for reservoir operationunder deficit conditions. To speed up the optimisationprocess, a neural network model is developed for thesimulation of the reservoir system operation and is usedinstead of a conventional simulation model. Thecombined neural network simulation–optimisation modelis used for screening the operation policies.

Bacterial and chemical quality of water supply in the Dertig village settlement

Abstract: Water contaminated with microbiological and chemical constituents can cause a variety of diseases. Water intended for human consumption should be safe, palatable and aesthetically pleasing. Water sources have different qualities influenced by natural or anthropological pollution. In South Africa, the availability of safe and clean water is a serious problem, especially in rural areas. Most people in such areas use water directly from available sources without any treatment and therefore are exposed to a variet y of water-related diseases. The objective of this study was to determine the chemical and microbiological quality of drinking wa ter supply to a rural community in order to estimate the health implications thereof. Water samples were collected weekly from five water sources, that is, Lefatlheng Well, Tlhaloganyo groundwater, Tlhaloganyo rain water, Matlaisane groundwater and Tshwane River in the Dertig/Lefatlheng village settlement which is in Hammanskraal, about 55 km north of Pretoria. To provide an indica tion of the microbiological quality of the water resources, indicator organisms including heterotrophic bacteria , faecal coliform, total coliform, Salmonella and coliphages were used. In order to support the results, bacterial isolates were identified using both the 20E and 20NE API systems to confirm their isolation. For the chemical quality analyses, different chemical quality variables includ ing temperature, pH, dissolved oxygen (DO), aluminium (Al), iron (Fe), manganese (Mn), fluoride (F), nitrate (NO 3 ), nitrite (NO 2 ) and colour were determined. The chemical quality of all the water sources analysed was acceptable. In contrast, however, the microbiological quality of all the water sources exceeded the standard for potable water and the sources pose a serious health risk to consumers.

Water Resource Management: Institutions and Irrigation Development in India

Abstract: This collection of essays seeks to provide a comprehensive, holistic view of the problem of water resource management, highlighting its technical complexity and the importance of devising appropriate institutional arrangements in combination with more imaginative technology for providing irrigation facilities.

Avoiding health risks from drinking water in Moscow: An empirical analysis

Abstract: Casual observation suggests that many households in Moscow boil water, settle water in pans for some periods (e.g., overnight) before consuming, filter water, and buy bottled water. To date, there has been little empirical analysis of such avoidance behavior. Based on a recently completed survey of 615 households in Moscow, this paper investigates the types and amounts of avoidance measures that are used by households in Moscow to adjust drinking water quality. Survey results show that this is clearly the case: over 88 per cent of the sample boil water regularly due to concerns about water quality; 23 per cent filter water regularly; over 30 per cent settle water regularly; and about 13 per cent buy bottled water regularly. On the other hand, residents are generally content with their cold water supply and quality of delivery. Based on a microeconomic model of household avoidance behavior, logit regression results show how avoidance decisions relate to income, opinions of water quality, and location in the city. It is expected that this analysis from Moscow can also be used as a guide for future studies in other cities in Russia to evaluate opinions of quality, avoidance measures, and citizens' willingness to support public infrastructure projects designed to improve water supply.

An Emerging Logic of Urban Water Management, Cochabamba, Bolivia

Abstract: This paper examines the emergence of a new logic of water management in developing cities. We argue that water provision is characterised by two largely disconnected circuits of water supply. Formally organised distribution networks provide a publicly subsidised service to higher-income users, while an informal system of water vendors provides a more expensive supply to marginalised communities. A new style of water management is now challenging the productionist logic that has created and maintained these dual networks. The case study of water privatisation in the city of Cochabamba, Bolivia, illustrates how this emerging logic is reconfiguring the management of urban water networks with a shift from large supply options towards greater consideration of user needs and extension of the network to unconnected communities. The productionist logic is in a period of profound transition as efforts are being made to mesh together more effectively the formal and informal networks. While this process is highly co...

Optimal Allocation of Irrigation Water Supplies in Real Time

Abstract: This paper presents an evaluation of the potential of an optimization approach in improving real-time irrigation water management in systems with complex distribution networks. The optimization approach is based on quadratic programming. The operational objective is to maximize crop production through appropriate water allocation, while maintaining equity between different irrigation schemes and units within schemes. The approach has been evaluated through application to the irrigation system in the Lower Ayung River Basin in Bali, Indonesia. A simulation model of this irrigation system was available, and it has been possible to measure the effectiveness of the optimization approach by comparing the results of simulation runs incorporating optimization with the results of runs representing existing water allocation practice. The results indicate that the optimization approach does have potential and can significantly improve crop production at the basin scale. This paper presents a preliminary assessment ...

Are stable agreements for sharing international river waters now possible

Abstract: International river and lake basins constitute about 47 percent of the world's continental land area, a proportion that increases to about 60 percent in Africa, Asia, and South America. Because water is a scarce and increasingly valuable resource, disputes about water allocation within these basins often contribute to regional tensions and conflicts. May principles of international law have been developed to allocate water within a water basin and to prevent or resolve international water disputes. Unfortunately, they rarely are easy to apply and often are contradictory. Sharing river water is particularly difficult because the effects are one-way, with upstream-downstream supply disputes have been among the most common. Agreements about the allocation of river water often last only until the first drought, when reduced flow denies some their full shares. The authors develop a simple formal model of water allocation among states within a river basin. They analyze the model in the context of variable flow rates, to project the behavior of riparian states during periods of above-normal and below-normal flow. Their objective: to understand when, where, and how much the economic interests of the states conflict, to develop principles guaranteeing efficient allocations of scarce water supplies, and to identify when stable (self-enforcing) allocation agreements are possible. They also consider the possibility of using alternative sources of supply and of accommodating growth in demand. Satellite technology will soon dramatically improve the ability of riparian states to predict annual flow volumes. In addition, water basin authorities will have real-time data on riparians' water use. These developments will have important implications for the enforceability and the flexibility of river water allocation systems. This model shows how flexibility can be used to construct more durable systems for sharing water among riparian states. The new allocation methods proposed here should contribute to the better management of scarce water supplies, a crucial issue in an increasingly thirsty world.

Quantitative bacterial examination of domestic water supplies in the Lesotho Highlands: water quality, sanitation, and village health.

Abstract: Reported are the results of an examination of domestic water supplies for microbial contamination in the Lesotho Highlands, the site of a 20-year-old hydroelectric project, as part of a regional epidemiological survey of baseline health, nutritional and environmental parameters. The population's hygiene and health behaviour were also studied. A total of 72 village water sources were classified as unimproved (n = 23), semi-improved (n = 37), or improved (n = 12). Based on the estimation of total coliforms, which is a nonspecific bacterial indicator of water quality, all unimproved and semi-improved water sources would be considered as not potable. Escherichia coli, a more precise indicator of faecal pollution, was absent (P < 0.001) in most of the improved water sources. Among 588 queried households, only 38% had access to an "improved" water supply. Sanitation was a serious problem, e.g. fewer than 5% of villagers used latrines and 18% of under-5-year-olds had suffered a recent diarrhoeal illness. The study demonstrates that protection of water sources can improve the hygienic quality of rural water supplies, where disinfection is not feasible. Our findings support the WHO recommendation that E. coli should be the principal microbial indicator for portability of untreated water. Strategies for developing safe water and sanitation systems must include public health education in hygiene and water source protection, practical methods and standards for water quality monitoring, and a resource centre for project information to facilitate programme evaluation and planning.

Domestic Water Use in Rural Semiarid Africa: A Case Study of Katarko Village in Northeastern Nigeria

Abstract: Katarko village in the Sahel region of northeastern Nigeria relies entirely on natural sources of water such as rainfall and ground water. Thelatter is potentially the only constant source of water. This study is based on primary data collected in Katarko during a period of 8 months in 1996. Analysis indicates that per capita daily water consumption is higher (44.9 l) in the rainy season than in the dry season (26.1 l). The proportion of households who useless than 150 l per day, the minimum daily requirement recommended by the World Health Organization (Dieterich & Henderson, 1963) increases from 29% during the rainy season to 67% during the dry season. Most households prefer to use water of poor quality that is to be found closer to their homes to traveling long distances to or spending extra time at the water sources to obtain good quality water. Poor water quality, appalling sanitation, and unhygienic water-handling practices, particularly during the dry season, contribute to the high incidence of diarrhea in the village.

Life cycle assessment of drinking water and rain water for toilets flushing

Abstract: Systems using rain water or reducing water consumption have been recently developed as an alternative to conventional toilet flushing. This article aims to quantify the environmental impacts of these systems and to identify key factors in each system. A Life Cycle Assessment (LCA) has been carried out to reach these goals. Scenarios with conventional water supplies present a lower energy requirement and lower environmental loads than recuperation scenarios. Sensitivity analyses indicate that recuperation is energetically favourable only when the energy required for the water supply is higher than 0.8 kWh/m3;, assuming a complex drinking water treatment. The study also reveals that low-flow toilets should be promoted as they lead to significant reductions in energy consumption and in pollutant emissions. A combination of a conventional water supply and low water consumption (scenario CONVeco) is advantageous for all environmental problems.