Showing papers on "Water supply published in 1997"

Accounting for water use and productivity

Abstract: This paper presents a conceptual framework for water accounting and provides generic terminologies and procedures to describe the status of water resource use and consequences of water resources related actions. The framework applies to water resource use at three levels of analysis: a use level such as an irrigated field or household, a service level such as an irrigation or water supply system, and a water basin level that may include several uses. Water accounting terminology and performance indicators are developed and presented with examples at all the three levels. Concepts and terminologies presented are developed to be supportive in a number of activities including: identification of opportunities for water savings and increasing water productivity; developing a better understanding of present patterns of water use and impacts of interventions; improving communication among professionals and communication to non-water professionals; and improving the rationale for allocation of water among uses. It is expected that with further application, these water accounting concepts will evolve into a robust, supporting methodology for water basin analysis.

Water Resources: Agriculture, the Environment, and Society

Abstract: This paper analyzes consumption of water by individuals agriculture and energy production by assessing the status of water resources. Furthermore it examines the relationship between water availability and biodiversity. The availability and quality of fresh water has become a major international problem. Limited water resources and inefficient water use combined with a rapidly growing population endanger the worlds finite fresh water supply. In many parts of the world per capita freshwater resources available for food production and for other human needs are declining and are becoming scarce in the arid regions. In fact agricultural productions account for approximately 87% of the worlds freshwater consumption. Moreover most of human activities adversely affect the quality of freshwater resources. Chemical and pathogen pollution of water supplies not only diminishes the quality of water but causes human health problems. Given these scenarios the freshwater problem can be prevented by 1) encouraging conservation and increasing efficiency of irrigation water by eliminating freshwater subsidies and encouraging developments in irrigation technologies; 2) giving farmers incentives to conserve water and soil resources; 3) controlling soil erosion; 4) protecting forests and other biological resources; and 4) preventing water pollution.

Water allocation mechanisms : principles and examples

Abstract: What does it mean to treat water as an economic good? What does it mean to allocate appropriately? From the earliest times, water resources have been allocated on the basis of social criteria - maintaining the community by ensuring that water is available for human consumption, for sanitation, and for food production. Societies have invested capital in infrastructure to maintain this allocation. Yet social change, including changes in (and more understanding of) how goods are distributed, has produced new issues in water allocation. Population growth has made water scarcity a major problem in many countries and water pollution, while by no means a recent problem, is more widespread than ever before. Traditionally the state has played a dominant role in managing water resources, but inefficient use of water, poor cost recovery for operating and maintenance expenses, the mounting cost of developing new water sources, and problems with the quality of service in agency-managed systems has led to a search for alternatives that make water allocation and management more efficient. Dinar, Rosegrant, and Meinzen-Dick address some of the basic principles of treating water as an economic good and of allocating it among sectors. After outlining the economic principles behind allocating scarce water resources, they review the actual means of various mechanisms used for allocating water, including marginal cost pricing, social planning, user-based allocation, and water markets. Giving examples from experience in several countries, they weigh the pros and cons of different approaches to water allocation, showing that no single approach is suitable for all situations. Clearly the state must play an important regulatory role, for example, but how effectively it does so depends on the relative political influence of various stakeholders and segments of society. User-based allocation is generally more flexible than state allocation, but collective action is not equally effective everywhere; it is most likely to emerge where there is strong demand for water and a history of cooperation. The outcome of market allocation depends on the economic value of water for various uses, but moving toward tradable property rights in water may ease the process of intersectoral reallocation by compensating the losers and creating incentives for efficient water use in all sectors. This paper - a joint product of the Sector Policy and Water Resources Division, Agriculture and Natural Resources Department, and the International Food Policy Research Institute - is part of a larger effort implement the 1993 World Bank`s Water Resources Management Policy.

'Virtual water': a long term solution for water short Middle Eastern economies?

Abstract: Summary The paper addressees the issue - why has there been no war over water when many economies in arid regions have only half the water they need and many leading figures, King Hussein, Boutros Boutros Gali, have warned that there would be a water war? It will show that the Middle East region has been able to access water in the global system via trade. Economic systems, not the evidently inadequate hydrological systems, have solved the water supply problem for the region. Water in the global trading system is know a ‘virtual water’. It is the water embedded in key water-intensive commodities such as wheat. The international wheat trade is a very effective and highly subsidised global trading system (ABARE 1989, LeHeron 1995) which operates to the advantage of water and food deficit countries. The problem The comparative disadvantage in economic terms of the Middle East and North Africa with respect to water is an extreme and classic case. Perceptions of the problem It is a paradox that the water pessimists are wrong but their pessimism is a very useful political tool which can help the innovator to shift the eternally interdependent belief systems of the public and their politicians. The water optimists are right but their optimism is dangerous because the notion enables politicians to treat water as a low policy priority, delay innovation, and thereby please those who perceive that they are prospering under the old order.

Population momentum and the demand on land and water resources

Abstract: Future world population growth is fuelled by two components: the demographic momentum, which is built into the age composition of current populations, and changes in reproductive behaviour and mortality of generations yet to come. This paper investigates, by major world regions and countries, what we know about population growth, what can be projected with reasonable certainty, and what is pure speculation. The exposition sets a frame for analysing demographic driving forces that are expected to increase human demand and pressures on land and water resources. These have been contrasted with current resource assessments of regional availability and use of land, in particular with estimates of remaining land with cultivation potential. In establishing a balance between availabilty of land resources and projected needs, the paper distinguishes regions with limited land and water resources and high population pressure from areas with abundant resources and low or moderate demographic demand. Overall, it is estimated that two-thirds of the remaining balance of land with rainfed cultivation potential is currently covered by various forest ecosystems and wetlands. The respective percentages by region vary between 23% in Southern Africa to 89% in South-Eastern Asia. For Latin America and Asia the estimated share of the balance of land with cultivation potential under forest and wetland ecosystems is about 70%, in Africa this is about 60%. If these were to be preserved, the remaining balance of land with some potential for rainfed crop cultivation would amount to some 550 million hectares. The regions which will experience the largest difficulties in meeting future demand for land resources and water, or alternatively have to cope with much increased dependency on external supplies, include foremost Western Asia, South-Central Asia, and Northern Africa. A large stress on resources is to be expected also in many countries of Eastern, Western and Southern Africa

A community waterborne outbreak of salmonellosis and the effectiveness of a boil water order.

Abstract: OBJECTIVES: A 1993 large water-borne outbreak of Salmonella typhimurium infections in Gideon, Mo, a city of 1100 with an unchlorinated community water supply, was investigated to determine the source of contamination and the effectiveness of an order to boil water. METHODS: A survey of household members in Gideon and the surrounding township produced information on diarrheal illness, water consumption, and compliance with the boil water order. RESULTS: More than 650 persons were ill; 15 were hospitalized, and 7 died. Persons consuming city water were more likely to be ill (relative risk [RR] = 9.1, 95% confidence interval [CI] = 2.9, 28.4), and the attack rate increased with increased water consumption. S. typhimurium was recovered from samples taken from a city fire hydrant and a water storage tower. Persons in 31% (30/ 98) of city households had drunk unboiled water after being informed about the boil water order, including 14 individuals who subsequently became ill. Reasons for noncompliance included "...

Water Resources in the Twenty-First Century: Challenges and Implications for Action

Abstract: In this paper, Mark W. Rosegrant assesses global water supply and demand, describes in detail the forces contributing to water scarcity, and lays out a number of strategies for managing water in the future. Any solution, Rosegrant asserts, will need to involve both the careful exploitation of new sources of water and strong measures to stimulate more efficient use of water. Policies must treat water not as a free good, as they often do now, but rather as a scarce commodity that comes at a price. Cooperation between countries sharing the same water basin will also become increasingly important as water becomes more scarce.

The Relative Efficiency and Implementation Costs of Alternative Methods for Pricing Irrigation Water

Abstract: A useful means for achieving efficient allocation of irrigation water is to put the right price tag on it. This article discusses some of the more pervasive pricing methods and compares their efficiency performance, paying special attention to the impact of the cost of implementing each method on its efficiency. The article uses an empirical example to demonstrate numerically the relative efficiency of the different pricing methods and the important role of implementation costs. The volumetric, output, input, tiered, and two-part tariff methods all can achieve efficiency, although the type of efficiency varies from one method to another. These methods also differ in the amount and type of information, and the administrative cost, needed in their implementation. The example indicates that water pricing methods are most pronounced through their effect on the cropping pattern, more so than through their effect on water demand for a given crop. Implementation cost have a large effect on water tariffs and on welfare and hence should have an important role in determining the desirable method to use in any given water situation.

Managing water resources for crop production

Abstract: Increasing crop production to meet the food requirements of the world's growing population will put great pressure on global water resources. Given that the vast freshwater resources that are available in the world are far from fully exploited, globally there should be sufficient water for future agricultural requirements. However, there are large areas where low water supply and high human demand may lead to regional shortages of water for future food production. In these arid and semi-arid areas, where water is a major constraint on production, improving water resource management is crucial if Malthusian disasters are to be avoided. There is considerable scope for improvement, since in both dryland and irrigated agriculture only about one-third of the available water (as rainfall, surface, or groundwater) is used to grow useful plants. This paper illustrates a range of techniques that could lead to increased crop production by improving agricultural water use efficiency. This may be achieved by increasing the total amount of water available to plants or by increasing the efficiency with which that water is used to produce biomass. Although the crash from the Malthusian precipice may ultimately be inevitable if population growth is not addressed, the time taken to reach the edge of the precipice could be lengthened by more efficient use of existing water resources.

Sustaining water easing scarcity: a second update.

Abstract: This Population Action International report re-estimates projected water supplies by 2050 in accordance with revised 1996 UN population projections. The report summarizes the causes and consequences of water scarcity and explains the importance of slower population growth. Water scarcity issues will depend in part on how rapidly population grows. Current estimates update a 1993 report. 400 million to 1.5 billion fewer people will live in water shortage countries by 2050 than had been previously projected. The improved scenario does not eliminate the concern about renewable freshwater scarcity for many millions. Currently over 430 million people live in countries experiencing water stress. By 2050 the percentage of people living in water-stressed countries will increase three- to five-fold. Data on population growth were obtained from "UN World Population Prospects: the 1996 Revision"; data on water supplies from "World Resources 1996-97: A Guide to the Global Environment." This revision is necessary because world population growth is slowing more dramatically than previously expected. Larger population size is the most significant human influence on the availability of fresh water. A Swedish hydrologist established a water stress index that indicates that humans require an estimated 100 liters/person/day for basic drinking bathing and cooking. 5-20 times this amount is needed to meet the demands of agriculture industry and energy. Countries with over 1700 cu. meters of renewable fresh water per person per year will experience intermittent or localized water shortages. Chronic and widespread water scarcity occurs under 1000 cu. meters. The figures refer to renewable fresh water. Figures do not account for nonrenewable groundwater timing or seasonality or adaptability of nations. Amounts above 1700 cu. meters do not assure an abundant freshwater supply at all times and in all places.

The public health implications of microbiological contamination of groundwater

Abstract: The microbiological contamination of groundwater has profound and severe implications for public health, particularly in small communities and developing countries where groundwater is often the preferred source of drinking water. Although natural groundwater is usually of good quality, this can deteriorate rapidly due to inadequate source protection and poor resource management. Contaminated groundwater can contribute to high morbidity and mortality rates from diarrhoeal diseases and sometimes lead to epidemics. The disposal of excreta using land-based systems is a key issue for groundwater quality and public health protection. The use of inappropriate water supply and sanitation technologies in peri-urban areas leads to severe and long-term public health risks. The use of poorly constructed sewage treatment works and land application of sewage can lead to groundwater contamination close to water supply sources. Microbiological, in particular virus survival in these circumstances is not well understood, but there are indications of extended pathogen survival and therefore increased public health risk.

Assessing Climate Change Implications for Water Resources Planning

Abstract: Numerous recent studies have shown that existing water supply systems are sensitive to climate change. One apparent implication is that water resources planning methods should be modified accordingly. Few of these studies, however, have attempted to account for either the chain of uncertainty in projecting water resources system vulnerability to climate change, or the adaptability of system operation resulting from existing planning strategies. Major uncertainties in water resources climate change assessments lie in a) climate modeling skill; b) errors in regional downscaling of climate model predictions; and c) uncertainties in future water demands. A simulation study was designed to provide insight into some aspects of these uncertainties. Specifically, the question that is addressed is whether a different decision would be made in a reservoir reallocation decision if knowledge about future climate were incorporated (i.e., would planning based on climate change information be justified?). The case study is possible reallocation of flood storage to conservation (municipal water supply) on the Green River, WA. We conclude that, for the case study, reservoir reallocation decisions and system performance would not differ significantly if climate change information were incorporated in the planning process.

Relating crop water consumption to irrigation water supply by remote sensing

Abstract: A new set of irrigation performance indicators based on remote-sensing estimates of evapotranspiration is introduced. These ‘evapotranspiration indicators’ are the relative evapotranspiration or crop stress and the water efficiency as well as their uniformity. With a remote-sensing evapotranspiration algorithm (SEBAL) maps of actual crop water consumption are derived. These maps are one of the inputs in the evapotranspiration indicators, together with GIS data (digitized irrigation unit boundaries) and field data (irrigation delivery schedule and water flow). This approach is applied on the Rio Tunuyan irrigation scheme, Mendoza, Argentina, which is served by surface water and privately owned ground water pumps. A homogeneous pattern of actual crop water consumption is detected from the highest irrigation level till the lowest (farm) level (coefficient of variance from 8.6% to 6.1% and 14.0% of secondary, tertiary and pixel level, respectively). Considering that a rotational irrigation schedule at tertiary and farm level is present, the results indicate that ground water supply through extraction and capillary rise equalize the spatial patterns in crop water consumption. The latter is proved by a comparison between (i) the areal water consumption from remote-sensing measurements, (ii) the areal water supply and (iii) additional field information on ground water extraction and capillary rise.

User organizations for sustainable water services

Abstract: This paper addresses the basic question: under what conditions are user organizations most effective in managing water systems? The first part examines the conditions under which sustainable water user associations (WUAs) can be fostered in the irrigation sector. The second part deals with water and sanitation users' associations (WASAs) in the domestic water supply and sanitation sector. Key external factors and internal structure for WUAs, as well as conditions for partnership with the government agency are identified. Sustainable associations in irrigation require a supportive policy and legal environment, and strong incentives for farmers, with particular attention to financial viability. Well defined roles, rights and responsibilities and incentives for agency staff are crucial for the success of WUAs. The need for agency reorientation to deal with user interests is emphasized. Benefits from participation and specific roles of WASAs must be identified in the country's policy and institutional context. Ultimately, the appropriate institutional arrangement between the government agency, the users, and their associations must meet the objective of improved and cost effective water services.

Making rural water supply sustainable : recommendations from a global study

Abstract: This study found that employing a demand-responsive approach at the community level significantly increases the likelihood of water system sustainability. However, it also found that even projects that have adopted this approach tend to apply it inconsistently among the communities where they work. The study found that to be effective, a demand-responsive approach should include procedures for an adequate flow of information to households, provisions for capacity-building at all levels, and a re-orientation of supply agencies to allow consumer demand to guide investment programs. The study also found that the existence of a formal organization to manage the water system and training of household members are significant factors in ensuring water system sustainability. Positive correlation were also found between water system sustainability and water committee training in operations and maintenance, and the quality of construction of the system and water system sustainability, although these findings are less consistent across countries.

Elevated CO 2and water supply interactions in grasslands: a pastures and rangelands management perspective

Abstract: Water is a key variable driving the composition and productivity of pastures and rangelands, and many of the ecosystems in these grasslands are highly sensitive to changes in water supply. The possibility that elevated CO2 concentrations may alter plant water relations is therefore particularly relevant to pastures and rangelands, and may have important consequences for grassland ecosystem function, water use, carbon storage and nutrient cycling. The planning of effective research to better understand these changes requires attention to both: (i) gaps in knowledge about CO2 and water interactions, and (ii) knowledge of how precisely the effects of CO2 must be understood in relation to other factors, in order to predict changes in grassland structure and production. A recent microcosm experiment illustrates that non-linear effects of CO2 and water stress could perturb primary production by triggering changes in grassland community composition. The magnitudes of the effects of CO2 on key grassland ecosystems remain to be precisely determined through ecosystem-level experiments. A simplified simulation of the impact of different levels of productivity change in a water-limited Australian rangeland system was conducted by varying effects of CO2 on radiation and water use efficiency. The results indicate that direct effects of CO2 may be moderated at the enterprise scale by accompanying changes in adaptive management by farmers. We conclude that future research should aim to construct quantitative relationships and identify thresholds of response for different grassland systems. The sensitivity of these systems to management (such as grazing pressure) should also be considered when developing integrated predictions of future effects of CO2 on water supply to grassland ecosystems.

Water, Rules and Gender: Water Rights in an Indigenous Irrigation System, Marakwet, Kenya

Abstract: The management of indigenous irrigation systems has received increasing attention both from social science researchers and from those development agents who seek to change them, or to find in them a model for organizing newly developed irrigation schemes. This article discusses how water is allocated within one such irrigation system, the hill furrow irrigation of the Marakwet escarpment in Kenya. It describes the ‘formal rules’ of water rights, giving particular attention to the issue of gender with respect to water rights. It then discusses the ‘working rules’ relevant to water allocation, involving various informal practices of sharing, buying and stealing. The implications of this complexity for understanding the operation of indigenous farmer-managed irrigation systems are examined.

The sustainable development of water resources: History, financial costs, and benefits of alien plant control programmes

Abstract: The water resources of the Western Cape province, and the catchment areas that produce them, need to be carefully managed if future demands for water are to be met. Good catchment management, in the form of programmes to control alien invasive plants. provides an additional means for preventing losses of water, but needs to be justified financially. Previous programmes aimed at the control of alien plants have been curtailed due to a lack of funds in the recent past, as they were conducted for reasons of nature, rather than water, conservation. However, recent studies have highlighted the impacts of alien plants on water resources, and have forced planners to take these impacts into account. In this paper, we review the history of alien plant control programmes, and assess the costs (financial) and benefits (in the form of reduced losses of water from invaded catchments) that would arise from such control. We use the standard practice of discounting future costs and benefits arising from planned and existing water supply schemes to estimate the relative efficiency of the schemes. By modelling the spread and effects of alien plants on streamflow, we show that alien plant control is effective and efficient. In the case of the proposed Skuifraam scheme (the preferred next option to supply water to Cape Town), water can be delivered at a cost of 57 and 59 c kl-1, respectively, with and without the management of alien plants, for example, indicating that such management is cost-effective. Clearing invasive plants from the existing Theewaterskloof catchment would deliver additional water at only 13.6% of the cost of delivery from the new Skuifraam scheme (unit reference values of 8 and 59 c kl-1 respectively). The analyses also show that an early investment in clearing is more cost effective than a later investment, as costs increase and yields decrease the longer the catchment is left to become more invaded. Many other benefits, including avoiding serious impacts on biodiversity, catchment stability and fire management, and enhancing social upliftment, have not been included in this assessment. and add to the argument for implementation of the programme for clearing invasive alien plants.

Distributing reclaimed water through dual systems

Abstract: Growing urbanization has put a heavy demand on limited sources of water for public community water supply systems. A proven conservation measure to help meet increasing demand is the reclamation of wastewater for nonpotable purposes. Reclaimed water can be used for landscape and recreational grounds irrigation, industrial processes, cooling towers, air-conditioning, stack gas scrubbing, toilet flushing, construction, firefighting, and environmental enhancement such as maintaining urban stream flows and wetlands. Urban reuse requires dual distribution systems that use one system for potable water and another for reclaimed water. Dual systems are particularly appropriate for urban developments now being planned, but they can prove cost-effective even for systems that must be retrofitted. The economies arise from savings in the acquisition and development of new water sources and facilities and in wastewater treatment and disposal. Because the public health risk from nonpotable reuse is minimall, public acceptance is high and even enthusiastic. Nonpotable urban reuse is an option worth consideration by municipalities seeking additional water supply to meet future needs.

Sharing water in Southern Africa

Abstract: The theme of the book is sharing and managing water resources in Southern Africa (i.e. the 12 SADC member countries). The introduction gives an overview of the contents of each chapter. Key issues like water as a natural resource, its availability (as influenced by climatic factors), water uses and related problems (water stress, population growth, urbanisation and others), water shared within a river basin and between countries are addressed in the various chapters. The last chapters is devoted to management of water resources: Management principles, levels of management, involvement of the private sector and NGO's, the role of Agenda 21 of the United Nations Conference on the Environment and Development and the Helsinki Rules, and supply versus demand management. The text and the many coloured illustrations are supplemented by a useful glossary, bibliographical references and an index.

Water resources development in africa: a review and synthesis of issues, potentials, and strategies for the future

Abstract: This paper analyzes how water resources development and water policy reform can be deployed to address the twin problems of food insecurity and water scarcity in Africa and, in particular, Sub-Saharan Africa. The paper reviews the current status of water supply and demand, and the existing and potential irrigated land base in Africa; reviews the performance of existing irrigation systems and assesses the magnitude of the potential contribution and cost-effectiveness of new irrigation development to future food production in Africa; and explores the potential for water conservation through demand management. Meeting the challenges of food security and water scarcity in Africa will require both selective development and exploitation of new water supplies and comprehensive policy reform that encourages efficient use of existing supplies. The most significant reforms will involve changing the institutional and legal environment in which water is supplied to one that empowers water users to make their own decisions regarding the resource. Irrigation development will not be the main source of food production growth in Africa, but increased investment in irrigation could have an important role in reducing projected cereal import demands. Rehabilitation and improvement of existing irrigation systems can be an attractive option, but projects must be selected carefully.

Shortage Management Modeling for Urban Water Supply Systems

Abstract: Water shortages throughout the world have shaped the development of demand management and supply enhancement options to improve water supply reliability. A shortage management model based on two-stage linear programming is presented as a tool to integrate available water resources options while accounting for costs and hydrologic uncertainties. To illustrate the approach, the model is applied to a simplification of the East Bay Municipal Utility District (EBMUD) system. The model is expanded in several case studies to demonstrate its strengths in incorporating the effects of seasonal shortages and uncertainties relating to long-term and short-term management options. Conclusions regarding the effects of uncertainties on shortage management are presented. A special examination is made of conditions encouraging economical development of dual distribution system.

Decentralization and coordination of water resource management

Abstract: 1. Introduction and Overview D.D. Parker, Y. Tsur. Part I: Regional Water Constraints: Middle East, California, Florida, and Australia. 2. The Israel Water Economy: An Overview D. Yaron. 3. The Jordan River Basin: Beyond National Concerns J. Kindler. 4. Water Resources in Turkey: Availability, Use, and Management E.H. Cakmak. 5. California's Water Resources and Institutions D.D. Parker. 6. Decentralized Water Allocation in Florida W.G. Boggess. 7. Australia's Water Situation: Resource Allocation and Management in a Maturing System J.J. Pigram. Part II: Economic Modeling of Decentralized Water Management Policies. A: Political Economy of Water Allocation. 8. The Political Economy of Domestic Water Allocation: The Cases of Israel and Jordan R.E. Just, et al. 9. Transboundary Water Agreements and Development Assistance G.B. Frisvold, M.F. Caswell. 10. Informational Imperfections in Water Resource Systems and the Political Economy of Water Supply and Pricing in Israel P. Zusman. 11. The Strategic Interdependence of a Shared Water Aquifer: A General Equilibrium Analysis T. Roe, Xinshen Diao. B: Water Institutions: Transition to Markets and Other Decentralized Allocation Mechanisms. 12. Designing Institutions for Water Management J. Roumasset. 13. Employing Market Mechanisms to Encourage Efficient Use of Water in the Middle East N. Becker, et al. 14. Efficient Management of Water in Agriculture D. Zilberman, et al. 15. Deriving Short-Run, Multistage Demand Curves and Simulating Market Prices for Reservoir Water Under Weather Uncertainty N. Dudley, B. Scott. 16. Water Institutions, Incentives, and Markets K.W. Easter, G. Feder. C: Incorporating Uncertainty in Resource Management Models. 17. On Event Uncertainty and Renewable Resource Management Y. Tsur, A. Zemel. 18. Quantifying Tradeoffs Between In-Stream and Off-Stream Uses Under Weather Uncertainty N. Dudley, B. Scott. 19. An Ex Ante Approach to Modeling Investment in New Technology A.P. Thurow, et al. 20. The Economics of Conjunctive Ground and Surface Water Irrigation Systems: Basic Principles and Empirical Evidence from Southern California Y. Tsur. Part III: Case Studies. 21. Peace and Prospects for International Water Projects in the Jordan-Yarmouk River Basin R.E. Just, et al. 22. Modeling the Impacts of Reducing Agricultural Water Supplies: Lessons from California's Bay/Delta Problem D. Sunding, et al. 23. Water and Conflict in the Twenty-First Century: The Middle East and California P.H. Gleick. 24. Decentralized Mechanisms and Institutions for Managing Water Resources: Reflections on Experiences from Australia W. Musgrave. Index.

Domestic water contamination in rapidly growing megacities of Asia : Case of Karachi, Pakistan

Abstract: The development of essential services including water and sanitation in many megacities of the economically developing countries of Asia cannot keep pace with their rapidly growing population and accompanying urban and industrial development. The inadequate water supply and poor sanitation services lead to contamination of their water supply. It also leads to the input of sewage water into the groundwater. The problem is seriously acute in Karachi, the largest city in Pakistan with a population of over 12 million and growing at 6 percent. This paper examines the problem of water contamination in Karachi. The paper presents the data on water quality from various sources, mainly municipal water supply, vendors and well water; the three major sources of water for domestic use in Karachi. Except municipal water from some areas and during certain periods, water from most other sources contain coliform bacteria, and in many cases faecal coliform, in amounts several magnitudes higher than any standards permit. Many samples have also been found to contain heavy metals including Chromium, Lead, Nickel and Arsenic in amounts excessive of permitted standards. The probable sources of contaminants for the various types of water (piped, vendors, wells) indicate that groundwater may be the main contributor. The very source of this groundwater is predominantly from sewage. The health hazards from consuming such contaminated water are obvious. The paper also evaluates the solutions that are being practiced, proposed or may be feasible, as well as those that are evolving.

Adapting to Climate Impacts on the Supply and Demand for Water

Abstract: The prospect of climate change adds to future water supply and demand uncertainties and reinforces the need for institutions that facilitate adaptation to changing conditions and promote efficient management of supplies and facilities. High costs and limited opportunities for increasing water supplies with dams, reservoirs, and other infrastructure have curbed the traditional supply-side approach to planning in recent decades. Although new infrastructure may be an appropriate response to climate-induced shifts in hydrologic regimes and water demands, it is difficult to plan for and justify expensive new projects when the magnitude, timing, and even the direction of the changes are unknown. On the other hand, evaluating margins of safety for long-lived structures such as dams and levees should consider the prospect that a greenhouse warming could produce greater hydrologic variability and storm extremes. Integrated river basin management can provide cost-effective increases in reliable supplies in the event of greenhouse warming. With water becoming scarcer and susceptible to variations and changes in the climate, demand management is critical for balancing future demands with supplies. Although regulatory and voluntary measures belong in a comprehensive demand management strategy, greater reliance on markets and prices to allocate supplies and introduce incentives to conserve will help reduce the costs of adapting to climate change. Federal water planning guidelines allow for consideration of plans incorporating changes in existing statutes, regulations, and other institutional arrangements that might be needed to facilitate water transfers and promote efficient management practices in response to changing supply and demand conditions.

Community participation: so what? Evidence from a comparative study of two rural water supply and sanitation projects in India.

Abstract: This comparative study on the two rural drinking water supply and sanitation projects in the state of Kerala India was conducted to determine the impact of community participation on the project outcomes. Both were piped water schemes delivered by the Kerala Water Authority (KWA); one had adopted community participation by the beneficiary community the other contained no community participation component. Project 1 was served by the Dutch/Danish project and Project 2 was served by KWA alone. A total of 160 respondents were involved in the study 80 individuals belonged to each project. Technological outcomes particularly in terms of water quality were found to be better in project 1 than in project 2. 40% of the people in Project 1 villages and 25% in Project 2 villages switched over completely to the "safe" water supply provided by the project. It was also found that the health habits of the beneficiaries in project 1 were far better compared to project 2 specifically in covering drinking water containers and use of latrines. In addition there was more continued community involvement in project 1 than in project 2. Satisfaction-wise the majority (75%) of respondents in project 1 areas claimed satisfaction with the project as compared to 30% of project 2 respondents.

The effects of water supply on infant and childhood mortality: a review of historical evidence.

Abstract: The provision of clean water is mentioned as an important factor in many studies dealing with the decline of mortality in Europe during the late nineteenth and early twentieth centuries. In developing countries too, improved water supply is assumed to have a strong impact on mortality. When studying the effect of water supply on public health, researchers are confronted with many methodological problems. Most of these also apply to historical studies of the subject. We review the evidence from this historical research, taking into account the methodological problems observed in contemporary impact evaluation studies, and we use more refined data from the Dutch city of Tilburg, enabling us to overcome many of these shortcomings. Finally, we discuss some factors which may explain why we failed to discover an effect of the availability of piped water on the level of childhood mortality.

California's 1995 Water Bank Program: Purchasing Water Supply Options

Abstract: In anticipation of a second consecutive critically dry year, the California Department of Water Resources (DWR) organized the 1995 Drought Water Bank Program. For the first time, DWR purchased water supply options from willing sellers as insurance against a possible water-short year. These options could be used by Water Bank members if needed to meet critical needs. If the options were not needed, sellers kept the option payment. This paper provides a program manager's view of the planning, management, operations, and financing of the 1995 Drought Water Bank Program and shares the writer's experiences in securing options to provide water supply certainty to California water agencies.