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Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers (1996)

Chapter: Water and Sanitation Services for Megacities in the Developing World

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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Water and Sanitation Services for Megacities in the Developing World

A Working Paper

Water Science and Technology Board

Commission on Geosciences, Environment, and Resources

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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PANEL ON SUSTAINABLE WATER AND SANITATION SERVICES FOR MEGACITIES

Members

John J. Boland, The Johns Hopkins University, Chair

Arthur E. Bruestle, The World Bank

Richard S. Engelbrecht, University of Illinois

Steven A. Esrey, United Nations’ International Children’s Emergency Fund

Donald T. Lauria, University of North Carolina

Walter R. Lynn, Cornell University

Rebecca T. Parkin, American Public Health Association

Peter P. Rogers, Harvard University

National Research Council Staff

Gary D. Krauss, Study Director

Ellen A. de Guzman, Project Assistant

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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WATER SCIENCE AND TECHNOLOGY BOARD

David L. Freyberg, Chair, Stanford University, Stanford, California

Bruce E. Rittmann, Vice Chair, Northwestern University, Evanston, Illinois

Linda M. Abriola, University of Michigan, Ann Arbor

Patrick L. Brezonik, Water Resources Research Center, St. Paul, Minnesota

John Briscoe, The World Bank, Washington, D.C.

William M. Eichbaum, The World Wildlife Fund, Washington, D.C.

Wilford R. Gardner, University of California, Berkeley

Thomas M. Hellman, Bristol-Myers Squibb Company, New York, New York

Carol A. Johnston, University of Minnesota, Duluth

William M. Lewis, Jr., University of Colorado, Boulder

John W. Morris, J.W. Morris Ltd., Arlington, Virginia

Carolyn H. Olsen, Brown and Caldwell, Pleasant Hill, California

Charles R. O’Melia, The Johns Hopkins University, Baltimore, Maryland

Rebecca T. Parkin, American Public Health Association, Washington, D.C.

Ignacio Rodriguez-Iturbe, Texas A&M University, College Station

Frank W. Schwartz, Ohio State University, Columbus

Henry J. Vaux, Jr., University of California, Riverside

Staff

Stephen D. Parker, Director

Sheila D. David, Senior Staff Officer

Chris Elfring, Senior Staff Officer

Gary D. Krauss, Staff Officer

Jacqueline A. MacDonald, Senior Staff Officer

Jeanne Aquilino, Administrative Associate

Etan Gumerman, Research Associate

Angela F. Brubaker, Senior Project Assistant

Ellen A. de Guzman, Project Assistant

Anita A. Hall, Administrative Assistant

Mary Beth Morris, Senior Project Assistant

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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EXECUTIVE SUMMARY

Water and sanitation services in the megacities of developing countries are inadequate for a large and rapidly growing number of urban residents. A history of nationally subsidized water services and lack of attention to cost recovery have limited the capacity of water and wastewater service providers to expand the network, treat water and wastewater, and fund repairs. In low-income communities, especially the squatter settlements that characterize many megacities, facilities for proper disposal of human wastes are seldom available; hygiene practices are generally poor; and water for household use is often inconvenient, insufficient, and contaminated. In many of the large cities, municipal and industrial wastewaters are rarely treated prior to disposal, and urban streams, rivers, and estuaries are severely polluted with human pathogens and toxic wastes. Diarrheal and respiratory infections that result from these conditions continue to be among the most frequent causes of sickness and death for infants and children.

To help improve the prospects for sustainable water and sanitation services for megacities in developing countries, a U.S. National Research Council panel focused on five areas that should receive the attention of national governments; external aid agencies; technical consultants; scientists; technicians; providers of water, wastewater, and other sanitation services; health services; and the leaders of the affected communities. (As used here, the term “sustainable” simply means that the services are capable of being continued over time without deterioration.) The result was a set of five approaches for achieving improved megacity water and sanitation services.

  1. Improved Sanitation. Water and sanitation professionals must take a broader view of sanitation to prevent disease resulting from a wide range of activities and multiple exposure routes. The provision of a potable water supply and wastewater removal are necessary but not sufficient conditions for improving public health. Water supply and wastewater management should be well integrated with other community, environmental, health, and nutritional programs to create a more robust and effective approach to healthcare and disease prevention. As opposed to the setting of standards by particular programs, activities, or media, an integrated approach should focus on end

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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results by considering and giving equal attention to all strategies and means for achieving those results in a cost-effective manner. Successful integration implies the avoidance of institutional barriers to the implementation of nontraditional approaches.

  1. Participatory Planning. Public water and wastewater service providers, health institutions, municipal and federal governments, and external aid agencies need to work together to place a higher priority on providing incremental water and sanitation improvements to the unserved residents of urban communities. This can be accomplished through participatory planning with the community, public education, and an openness to innovative technical approaches. These strategies should be compatible with the aspirations of the communities involved, their ability to maintain and upgrade the system, and the services people want and for which they are willing to pay.

  2. Financing. All people, including the very poor, are willing to pay a reasonable fee for convenient and reliable access to safe drinking water and the safe elimination of household waste. It follows that providers of drinking water and wastewater services should strive to become financially sound and self-sufficient entities that can collect revenues from customers sufficient to maintain and expand system services as needed.

  3. The Role of Technology. Technical innovation should be based on carefully considered performance criteria appropriate to maintaining a healthy environment. The private sector can be an important contributor to the development of locally new technology and the provision of services. However, the participation of the private sector in service delivery and technology innovation requires the right market incentives, sound government policy, and appropriate and enforceable laws and regulations.

  4. Water Conservation and Reuse. By their very nature, megacities have larger impacts on water resources and suffer greater constraints on obtaining water than smaller urban or rural settlements. Effective management of water resources requires a holistic approach that considers water quantity, quality, and use within an entire watershed or catchment area. Conservation of water resources should be a priority for all megacities, and the value of water should be reflected in the design of tariffs and the metering of users. With appropriate treatment, reclamation and reuse of municipal wastewater for nonpotable uses can become an increasingly cost-effective conservation measure.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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INTRODUCTION

This paper examines the challenge of improving water and sanitation services in the megacities of the developing world. Following a review of the current situation, it presents approaches to improved services in five areas: improved sanitation, participatory planning, financing, the role of technology, and water conservation and reuse.

REVIEW OF THE CURRENT SITUATION

After the United Nations declared the 1980s the Drinking Water Supply and Sanitation Decade, concerted efforts were made by both governments and external support agencies to improve the delivery of drinking water and sanitation services in developing countries (United Nations Development Programme, 1994). Yet while the coverage of urban drinking water services has improved over the last decade, the number of urban residents without adequate means to dispose of their household wastes has continued to grow (World Bank, 1992) (see Figure 1 ). In providing for wastewater removal, governments have generally focused on constructing sewers in city centers. Wastewater services rarely reach the poor residents living on the urban periphery or in informal settlements, where open drains and ditches commonly collect household waste. In most developing-country megacities, wastewater is rarely treated prior to disposal, and urban streams and rivers have become little more than sewage canals, carrying almost undiluted human and animal excreta, refuse, and industrial waste.

Where drinking water service is presumed to be adequate and safe, the distribution systems are often poorly maintained and may suffer from leaks and intermittent system pressure. Negative pressure inside the pipe allows contaminated water from the surrounding soil to infiltrate the distribution system. Tests of household tap water in Mexico City, for example, showed significant variation in the percentage of samples that met the standard for microbiological safety (as measured by the chlorine residual), ranging from full compliance to as low as 16 percent among the political jurisdictions of the metropolitan area (National Research Council, 1995).

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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FIGURE 1 Access to water and sanitation service in urban areas of developing countries, 1980 and 1990. Sanitation service in this figure indicates public sewers. Source: Adapted from World Bank (1992) from World Health Organization data.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
×

Foreign aid and other investments have traditionally focused on the development of drinking water supplies to the exclusion of wastewater systems and other aspects of sanitation. Relative to the amount spent on water services, sanitation has received only 15 percent of the total lending in the water and sanitation sector of the World Bank over the past 30 years (Bartone, 1994). This emphasis has reflected, in part, the priorities of borrower governments. From an economic perspective, investment in water supply encourages industrial and commercial development and has contributed to the growth of megacities. These large cities are often the engines that drive the development process for countries in the early stages of modernization. The demand for a convenient and adequate water supply for the urban family is often seen as a higher priority than wastewater removal, especially for poor urban residents. However, part of the reason for the perceived lack of demand for wastewater services is that very few options have been available or presented to unserved communities.

The health consequences of inadequate drinking water and wastewater services fall most heavily on the poor. Urban populations in developing countries are growing most rapidly in the low-income, high-density districts, including the informal settlements (also termed squatter areas, favelas, shantytowns, and villas misérias) that can be found in most developing-country megacities. In these areas, there are few or no facilities for proper disposal of human wastes; water for household use is rarely convenient or sufficient and is often contaminated; hygiene is poor; and in the event of illness, access to medical treatment is difficult. Diarrheal diseases from gastro-intestinal and parasitic infections and acute respiratory illnesses resulting from these conditions are among the leading causes of sickness and death among infants and young children in the developing world (World Bank, 1993). It is estimated that in the developing countries, 3.2 million children under the age of 5 die each year from diarrheal diseases (World Health Organization, 1992). The disparity between those with and without access to clean water and a clean environment is strikingly evident within most large urban areas. Mortality rates are between 2 and 10 times higher for children living in the squatter areas of a city than for children living in areas with adequate drinking water, wastewater, and medical services and better nutrition and hygiene practices (Stephens, 1995). Even with deteriorating services, the more well-to-do can afford to either boil water or subscribe to services that guarantee convenient and good-quality water.

The problem of lack of coverage for water and wastewater services has been the subject of numerous international forums and reviews. A declaration and plan of action to improve health, including safe water, wastewater removal, and other aspects of sanitation, was adopted in 1990 at the United Nations World Summit for Children and had been joined by 174 countries as of July 1995. The growing threat to public health and the environment from the scarcity and misuse of fresh water was recognized by 100 countries and 80 international, intergovernmental, and nongovernmental organizations at the International Conference on Water and the Environment in Dublin, Ireland, in 1992. In March 1994, representatives of governments met at the Ministerial Conference on Drinking Water and Environmental Sanitation in The Netherlands to assess the Drinking Water and Sanitation Decade of the 1980s and to develop an action program to implement the United Nations

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Conference on Environment and Development Agenda 21. The resulting statements stressed the need for integrated water resources management and a recognition that safe water in sufficient quantities and proper sanitation need to be provided to all people. Other resolutions from the Ministerial Conference focused on the need for emphasizing waste reduction and pollution prevention, enabling local partnerships to deliver local services in accordance with expressed needs and a willingness to pay, and giving priority to populations at greatest risk. Many of the themes of these international forums are reflected and reinforced in the approaches presented in the next section of this paper. 1

Historically, high subsidies in many countries have allowed large numbers of people to have access to drinking water and wastewater services at artificially low cost. While subsidies for these services are often promoted as antipoverty measures, the beneficiaries tend to be the wealthier residents of the city. Residents in low-income areas generally do not have in-home or on-property access to drinking water and must make do with high-cost and/or labor-intensive substitutes, such as carrying water long distances or paying high prices to water vendors. It is well documented that the urban poor not only pay a high proportion of their income for water (often 20 percent or more), but often pay more per month. In some cases, drinking water from vendors costs 25 to 50 times more per unit of water than the cost to households connected to the subsidized municipal system (World Bank, 1993). As a result, there is often insufficient clean water for the basic necessities of personal hygiene, household cleaning, and food preparation.

With the false security of subsidies, government agencies that manage water and wastewater services have had little incentive to build institutional capacity or a sense of responsibility to the consumer. Water use is rarely metered, and billing systems are dysfunctional. Given the general scarcity of all public revenues and the escalating problems of large cities, water subsidies are shrinking in many places. Without the necessary operating funds, water and wastewater service providers lack the capacity to perform needed repairs or expand systems to serve new users. Service deteriorates, customers lose confidence, and revenues decline. In such circumstances, service providers have difficulty obtaining new loans or investments.

The short- and long-term consequences of inadequate water and wastewater services are costly to society as a whole. Infectious and parasitic diseases linked to poor sanitation are the third leading cause of poor worker productivity in the developing world (World Bank, 1993). Without a piped water supply, one or more members of each household may spend otherwise productive hours each day carrying water from a standpipe, tubewell, spring, or stream.

1  

It should be noted that there has been no attempt to be comprehensive in the topics presented in this paper. See United Nations Development Programme (1994) for a summary of the major international meetings on water resources, water supply, and sanitation.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
×

By their very nature, megacities have larger impacts on water resources than do smaller urban or rural settlements. Large quantities of surface water may be diverted, denying water supplies to downstream users. As a result of inadequate wastewater management, surface waters can become severely polluted, compromising the quality and availability of future supplies and creating future health risks. While ambient water quality improved in industrialized countries during the 1980s, it did not improve in middle-income countries, and it declined sharply in lower-income countries (World Bank, 1992). Large-scale development can impair important ground water recharge areas. Ground water is often extracted in excess of the aquifer’s natural recharge rate, and the results may include falling water tables, land subsidence, increased pumping costs, degraded water quality, and eventual exhaustion. All of these activities can change the character of the area’s water resources, potentially reducing their ability to provide for the future.

Over the next two decades, population growth and migration will add an estimated 1.3 billion new urban residents who will require sanitation services (Bartone, 1994). Of these, 25 percent will live in megacities with populations of over 10 million. The growing periurban areas present a serious public health and environmental problem that will not be solved by traditional approaches to water and wastewater planning. Given these circumstances, how can the delivery of water and wastewater services be improved and expanded?

The challenge is great. Water and wastewater service providers, health institutions, municipal and national governments, community organizations, and external aid agencies need to work together to improve incrementally the health, productivity, and quality of life of megacity residents. We turn now to some approaches by which this can be accomplished.

APPROACHES TO IMPROVED SERVICES

Improved Sanitation

Progress in improving public health requires parallel and integrated improvements to drinking water supplies, wastewater management, and other aspects of sanitation.

Sanitation is defined as the management of environmental conditions and the provision of services to prevent and control the spread of disease and enhance the welfare and well-being of human populations. Sanitation encompasses a wide range of activities, including the safe disposal of human and animal excreta and other domestic wastes; personal cleanliness; proper food handling; animal vector control; air quality control; proper management of wastes from urban commercial, industrial, and agricultural activities; and provision of a safe, sufficient, and convenient supply of water for household and other community needs.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Among water professionals, however, the term “sanitation” has become synonymous with wastewater collection and disposal in urban settings or with latrines in rural settings. Consequently, urban water and sanitation planning has focused on large, central water and wastewater management systems. This narrow view of sanitation diverts attention from important preventive strategies that are more appropriate for the rapidly growing cities of the developing world. To be effective in improving human health, programs for water supply, human waste disposal, and municipal wastewater management should be well integrated with other environmental, health, and nutrition programs. Continued high rates of disease and death, as well as chronically depressed worker productivity, argue strongly for a higher profile, a broader definition, and better funding for sanitation than in the past (UNICEF, 1995).

As opposed to the setting of standards by particular programs, activities, or media, an integrated approach should focus on end results by considering and giving equal attention to all strategies and means for achieving those results in a cost-effective manner. Successful integration implies the avoidance of institutional barriers to the implementation of nontraditional approaches. For example, major gains have been achieved in reducing the incidence of dracunculiasis or Guinea worm disease--a debilitating water-borne disease--through integrated programs that link water supply, health education, and surveillance (World Bank, 1993). Integration also means avoiding institutional overlap, redundancy, and rigid boundaries. To illustrate, Lauria et al. (1993) describe a situation in the Philippines in which the responsible institution did not have the flexibility to respond to the principal concern of the affected communities--their solid waste problem--because the externally funded program was set up to deal exclusively with wastewater management.

In western industrialized countries, many infectious diseases were brought under control by improved sanitation long before curative treatments became available. In the United States, broad sanitary improvements during the early 1900s were associated with declines in typhoid, gastrointestinal infections, and other diseases (McKinlay and-McKinlay, 1977). In France, the provision of piped water in many major cities did not significantly improve public health until it was accompanied by the covering of open sewage drains and adequate disposal of wastewater (Preston and van de Walle, 1978). Similar circumstances have been cited for Great Britain (McKeown and Record, 1962).

The epidemiological evidence from developing countries indicates that improving hygiene and disposal of excreta and ensuring a sufficient quantity of water close to the home environment (e.g., an in-house tap or one on the premises) has a larger impact on human health than do improvements to drinking water quality alone, and this evidence is more compelling in urban than in rural locations (Esrey, 1996; Esrey et al., 1991; Bateman and Smith, 1991). Incremental improvements in disposal of excreta are clearly associated with fewer parasitic infections, better growth of children, and lower mortality rates (see also Butz et al., 1984; Esrey and Habicht, 1988; Esrey et al., 1992; Koopman et al., 1981; Yee, 1984; Young and Briscoe, 1987). Several studies also indicate that better hygiene practices, including disposal of infant feces, significantly improve health (Aulia, 1994; Huttly, 1994;

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Zeitlin, 1995; Dikassa, 1993). VanDerSlice and Briscoe (1995) caution against putting too much faith in the apparent benefits of a specific intervention because of interactions among many factors. It is clear that the provision of a potable water supply and wastewater removal are necessary but not sufficient conditions for improving public health; all aspects of sanitation will need attention.

The rapid evolution of drug-resistant strains of infectious diseases emphasizes the need for better preventive measures to control disease. Shigella infection, for example, is an important cause of diarrheal morbidity and mortality in less-developed areas of the world. Shigellosis occurs in conditions of crowding, poverty, inadequate water supplies, and poor personal hygiene. The use of tetracycline to treat shigellosis has been abandoned because of widespread microbial resistance, and strains of Shigella are now increasingly resistant to amoxicilin and to more expensive drag therapies. Resistant strains have emerged in the United States among travelers, on American Indian reservations, and in other endemic settings (Turtle and Tauxe, 1995). In these situations, the decision to prescribe antimicrobials must be weighed against the public health risks of promoting drug resistance. The U.S. Centers for Disease Control has recommended improving sanitation as the most effective way to prevent exposure to the pathogens and incidence of shigellosis (Tuttle and Tauxe, 1995).

In developing countries, improvements in sanitation will require better training and involvement of sanitation professionals. Yet the number of people trained as sanitarians has been decreasing. This trend has been caused by a number of factors, including decreased emphasis on sanitation in public health programs, fewer specialized academic and continuing education programs, relatively low salaries for sanitarians, and a lack of knowledge and understanding by the public about sanitation services relative to other public services. The growing sanitation challenges of megacities require expanding the scientific and technical base of sanitation, developing systems to disseminate that information, and fielding trained workers to apply the knowledge and make it available to communities. Hygiene education should be an integral part of future water and sanitation programs, and recent information on strategies for improving sanitation should be provided to the medical profession. Interdisciplinary and intersectoral approaches should be taken for research, planning, training, and evaluation of programs to improve health (see Boot and Cairncross, 1993).

The role of education in promoting better personal and community hygiene is illustrated by a community educational program in Egypt (El-Katha and Watts, 1994). Many communities had been provided with upgrades in potable water service, but diarrhea rates remained high. The new program provided for education in health clinics to advise parents with sick children, and special summer camps were set up to educate older children (and, indirectly, their parents).

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Participatory Planning

Sustainable water and wastewater improvements must address the informed preferences of the community. Participatory planning, combined with public education, can identify those services that people want and for which they are willing to pay.

Historically, water and sewer projects in developing countries have been characterized by a “top-down” planning approach that involves principally government officials and consultants of the external support agencies. Recipients of the services and other stakeholders are rarely consulted, and poorer communities, especially informal settlements, are typically ignored. More recently, however, community participation has taken a more prominent role in lender policy (World Bank, 1996).

The principle of participatory water management was enunciated at the 1992 Dublin International Conference on Water and the Environment. According to this principle, “water development and management should be based on a participatory approach, involving user, planners, and policy makers at all levels. . .with decisions taken at the lowest appropriate level” (United Nations Development Programme, 1994). Institutionally, this means planning must be done at a level that allows local and regional agencies to make effective and coordinated water management decisions. For a system to be sustainable, all stakeholders must believe that their needs are being met satisfactorily. (As used here, the term “sustainable” simply means that the services are capable of being continued over time without deterioration.) The community should be consulted and drawn into the planning process in an effort to identify local needs and preferences and determine whether there exists sufficient willingness to pay for improved services.

Most urban households, regardless of income level, desire affordable water and sanitation services. It is well documented that even the poor in developing countries are willing and able to pay the full cost of a potable water supply (Crane, 1994; Okun, 1991; Whittington and Choe, 1992; World Bank, 1992). Nearly all studies of major cities in developing countries show that monthly water expenses are a much larger share of income and often larger in absolute terms for the poor as compared with the wealthy (Crane, 1994; Ingram et al., 1995; Roth, 1985; World Bank, 1992). When public water service is inadequate or nonexistent, people must obtain their water in other, much more expensive ways.

Where public drinking water service or wastewater collection and disposal systems have not been made available, some communities, often aided by nongovernmental organizations, have become involved in the planning and delivery of these services. In such cases, institutional and technology alternatives need to be developed and offered, including options that are not routinely used for centralized systems in industrialized countries.

Community-based service delivery places the users in a command position, enabling them to choose more directly the delivery technology, the level and quality of service, and, consequently, the cost of the service. This engenders a sense of ownership and respect for the system and a willingness to pay. Moreover, it relieves the central government agency of

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
×

the costly and often unsatisfactory provision of these services. Of course, the central government should create an environment that fosters such an approach, and this may require hiring people with the appropriate community-development skills.

Formal institutions (utilities and municipalities) have combined with informal institutions (community groups and nongovernmental organizations) in producing low-cost, innovative wastewater collection services in Brazil. A community initiative, which started in northeast Brazil, was financed by the World Bank, and the strategy is now widely used in other regions of the country.

Communicating and providing information to the consumer is usually necessary to raise public awareness regarding the importance of sanitation to public health and the value of water. Informed consumers are more likely to become willing participants in programs designed to improve their lives.

The Condominial Sewerage System in Brazil

The “condominial” sewerage system is the brain-child of Jose Carlos de Melo, a socially committed engineer from Recife. Its name has two sources. First, a block of houses is treated like a horizontal apartment building or condominial in Portuguese. Second, “Condominial” was a popular Brazilian soap opera, associated with the best in urban life. The system has an innovative layout, with a shorter grid of smaller and shallower “feeder” sewers running through the back yards and with the effects of shallower connections to the mains rippling through the system. These innovations cut construction costs to between 20 and 30 percent of those of a conventional system.

The more fundamental and radical innovation, however, is the active involvement of the population in choosing their levels of services and in operating and maintaining the feeder infrastructure. The key elements are that families can choose (1) to continue with their current sanitation system; (2) to connect to a conventional water-borne system; or (3) to connect to the condominial system, whereby individual households are responsible for maintaining the feeder sewers, and the formal agency tends to the trunk mains only.

The condominial system is now providing service to hundreds of thousands of urban people in northeast Brazil and is being replicated on a large scale throughout the country. The danger, however, is that the clever engineering is seen as “the system.” Where the community and organizational aspects have been missing, the technology has worked poorly (as in Joinville, Santa Catarina) or not at all (as in the Baixada Fluminense in Rio de Janiero).

Source: Adapted from World Bank (1992).

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Financing

Subsidies should not be squandered on services the public is willing to finance. Where external funds are available, they should be reserved for services with collective benefits, such as wastewater treatment. It follows that providers of drinking water should strive to become financially sound and relatively autonomous entities that can collect revenues from customers sufficient to maintain and expand system services as needed.

Given the general scarcity of public revenues, the levels of external funding historically provided for drinking water service are no longer available. Water authorities realize that they must look to their customers for the funds to construct, operate, and maintain improved facilities.

The practice of cost recovery requires the technical and administrative ability to operate an effective pricing system (Gunnerson, 1991; Bahl and Linn, 1992; Ostrom et al., 1993). A pricing system requires metering of the water supply to each customer. However, unless the public has confidence in the system, they will not connect, will not pay, and may break the meters. Thus, the initial installation of meters must be supported by an adequate system of maintenance and repair (including recalibration of meters at appropriate intervals). The meters must also be read at regular intervals. Water accounts should be prepared and bills delivered with the least possible delay after meter reading. Finally, payment of accounts within a reasonable time must be enforced, with genuine penalties for late payment. Improvements to administrative and technical capacity must go hand in hand with policy innovations, such as tariff reform, if the desired results are to be achieved. Though not likely to happen initially, the goal of water pricing is to cover the replacement cost of supply, including capital costs, operation and maintenance, and administration (Rogers, 1993).

The financing strategy for water and wastewater systems should reflect the population’s willingness to pay for water supply services and the need to address social goals, including fairness and equity. Operationally, this may mean subsidizing the very poor to ensure that a minimum quantity of water is available for basic sanitation needs. In Monterrey, Mexico (a heavily industrialized metropolitan area of 3 million), there is 100 percent metering. Low-income households pay a modest fixed monthly tariff for consumption of less than 20 cubic meters per month. For consumption in excess of this minimum, every cubic meter is charged a unit price. Thus large users pay more on average and effectively subsidize the low-consuming households.

Care should be taken that such subsidies do not affect the overall financial viability of the system. The full recovery cost of the system needs to be established before the tariffs are set to effect this cross-subsidy. Whittington (1992) describes a situation in Kumasi, Ghana, where the poor were using more water per connection and being charged higher rates than the rich because of multiple family use of a single, metered connection. In situations such as this, every effort should be made to ensure that each family is billed appropriately for water use, even if meters are not available for each unit. Without such financial incentives, there will be inequity and free-rider problems, even among the subsidized poor.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Innovative Sewerage in a Karachi Informal Settlement: The Orangi Pilot Project

In the early 1980s, Akhter Hameed Khan, a world-renowned community organizer, began working in the slums of Karachi. He asked what problem he could help resolve and was told that “the streets were filled with excreta and wastewater, making movement difficult and creating enormous health hazards.” “What did the people want, and how did they intend to get it?” he asked. What they wanted was clear: “People aspired to a traditional sewerage system. . .it would be difficult to get them to finance anything else.” And how they would get it, too, was clear: they would have Dr. Khan persuade the Karachi Development Authority (KDA) to provide it free, as it did (or so the poor perceived) to the richer areas of the city.

Dr. Khan spent months accompanying representatives of the community to petition the KDA to provide the service. When it was clear that this would never happen, Dr. Khan was ready to work with the community to find alternatives. (He would later describe this first step as the most important thing he did in Orangi, liberating the people, as he put it, from the immobilizing myths of government promises.)

With a small amount of core external funding, the Orangi Pilot Project (OPP) was started. It was clear what services the people wanted; the task was to reduce the costs to affordable levels and to develop organizations that could provide and operate the systems. On the technical side, the achievements of the OPP architects and engineers were remarkable and innovative. Thanks partly to the elimination of corruption and the provision of labor by community members, the costs (for an in-house sanitary latrine and house sewer on the plot and underground sewers in the lanes and streets) were less than $50 per household.

The related organizational achievements are most impressive. OPP staff members have played a catalytic role: they explain the benefits of sanitation and the technical possibilities to residents, conduct research, and provide technical assistance. The OPP staff never handle the community’s money. (The total costs of the OPP’s operation amounted, even in the project’s early years, to less than 15 percent of the amount invested by the community.) The households’ responsibilities include financing their share of the costs, participating in construction, and electing a “lane manager,” who typically represents about 15 households. Lane committees, in turn, elect members of neighborhood committees (typically representing about 600 houses), which manage the secondary sewers.

The early successes achieved by the project created a “snowball” effect, in part because of the increased value of properties with sewerage systems. As the power of the OPP-related organizations increased, they were able to put pressure on the municipality to provide funds for construction of trunk sewers.

The OPP has led to the provision of sewerage services to more than 600,000 poor people in Karachi. It has also led to recent initiatives by several municipalities in Pakistan to follow the OPP method and, according to OPP leader Arif Hasan, “have government behave like a nongovernmental orgznitation.” Even in Karachi, the mayor now formally accepts the principle of “internal” development by residents and “external” development (including trunk sewers and treatment) by the municipality.

Source: World Bank (1992).

In Jakarta, poor residents are unable to afford the one-time cost of a water hook-up, even though they may pay more over the long term to purchase water from private vendors. In

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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such cases, subsidies or the availability of small loans for a hook-up would enable new customers to gain access to the system. In Santiago, Chile, the central government, through the municipalities, pays a lump sum subsidy for qualifying urban poor. This ensures that low-income households have access to drinking water and wastewater services without compromising the financial viability of the water agency.

The appropriate financing arrangements for wastewater collection, treatment, and disposal are complex because the benefits perceived at the individual household level are different from those to larger aggregates of society. Individuals are more willing to pay for services that provide direct benefits to their family and property and less willing to pay for services that provide environmental benefits they do not perceive. A household will place high value on a private, convenient, and sanitary facility for removing excreta and wastewater from the property. Moving up a level, to that of the neighborhood, residents may value services for removing excreta and wastewater from the neighborhood or rendering these wastes innocuous through treatment. Neighborhoods and cities, however, do not exist in isolation, and wastes discharged at one point may affect the health of people downstream. National economic, health, and environmental concerns over water quality and water allocation may also come into play (Bartone, 1994; see also National Research Council, 1993a). The provision of wastewater collection, treatment, and disposal services may thus need to be subsidized from water revenue or other sources. Central governments should seek ways to facilitate the autonomous operation of local water utilities. Such policies include (1) enacting legislation that will enable utilities to function independently and assume local responsibility, (2) eliminating political interference in the operation of local utilities, (3) providing and enforcing regulations for oversight and protection of consumers, and (4) working for the development of in-country financing of water and sanitation independent of external support agencies.

The policies and consequent good performance discussed above may be and sometimes are achieved by government. However, where existing public sector performance is poor, attempts at reform often fail because of entrenched special interests and inappropriate incentives. Over the last decade there has been a considerable increase in experimentation with various forms of private sector participation. This alternative can be useful if it introduces competition or other constructive economic incentives, which in turn stimulate better performance (Idelovitch and Ringskog, 1995). Private sector participation may range in form and degree from simple service and management contracts for a defined activity (e.g., maintenance or bill collection) to complete divestiture, where private firms competitively purchase assets from the government and assume complete control. Most fails somewhere between these extremes (see Walker, 1994, for a detailed overview of the options). The City of Abidjan in the Ivory Coast has had its water services operated by a private company under a lease contract (initially foreign-owned, the company is now majority-owned by Ivorians) (World Bank, 1994). This arrangement has been highly successful in getting quality services at reasonable cost to all people, and in attracting investment (the company, SODECI, trades shares on the stock market in Abidjan).

Successful private sector participation and community-based options can deliver many benefits: meeting consumer demands at lower cost, removing the need for government subsidies, assisting in capital formation, and promoting economic efficiency and

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Meeting the Demand for Sanitation Services: The Favelas of São Paulo

In the 1980s, the Brazilian city of São Paulo made extraordinary progress in providing all its residents with water supply and sanitation services. In 1980, just 32 percent of the favelas (low-income informal settlements) had piped water supply, and less than 1 percent had a sewerage system. By 1990, the respective figures were 99 and 15 percent.

SABESP, the state water utility serving São Paulo, is a technically sophisticated water supply organization. Until the emergence of democracy in Brazil, SABESP had defined its role narrowly and technocratically. Specifically, it did not consider provision of services to the favelas to be its responsibility because this could not be done according to its prescribed technical standards and because the favelas were not “legal.” Meanwhile, a small agency (COBES) was experimenting with new technical and institutional ways of providing water and sanitation services to the poor. On the technical side, this did not involve the provision of inferior service, but reduction of the cost of providing in-house services by using new materials and approaches that enabled service in narrow roads where access was limited. On the institutional side, the community had to assume significant responsibility for community relations and for supervision of the work of contractors.

As the military regime withdrew and was replaced by a democracy in the early 1980s, the pressures on SABESP to serve the favelas increased. Community pressure was channeled through the municipal agencies and responsive officials and politicians, including the mayor and governor. Since COBES had shown how it was, in fact, possible to serve the favelas, SABESP had no option but to respond.

The lesson from São Paulo is that where institutions are responsive and innovative, progress can be made in the provision of water and wastewater services at full cost to the poor.

Source: World Bank (1992).

development. However, its success requires sound policy, relevant laws, and regulations that are adequately enforced, which means that government and local institutions must be strengthened. As a first step, existing public water and wastewater institutions need to recognize poor communities as part of their customer base.

The Role of Technology

Megacities need more technology choices to provide services in flexible, adaptable, and affordable ways. In particular, service to the informal settlements of metropolitan areas will require innovative and incremental approaches.

Although the obstacles to meeting the water, sanitation, and wastewater needs of megacities are many, there are at least two reasons to expect that technological change can play a role in overcoming them. First, the dearth of existing water and wastewater infrastructure means that megacities in developing countries need not be locked into technical approaches that are poorly suited to them. Second, the scientific understanding underlying water and wastewater treatment technologies has greatly advanced since the processes were developed in the first half of the twentieth century. Therefore, a rethinking of technology in

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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the context of megacity needs may lead to novel technological approaches that are less expensive to build and operate and more compatible with the needs and capabilities of the user communities.

Innovation may be essential to addressing the needs of areas that have been difficult or impossible to serve under existing arrangements. Innovation is defined here as the first adoption by a culture or society of a method for providing goods and services that the society uses. Thus, innovation involves not only what is new, but also what is locally new. Innovation involves aspects of technology, organization, community, and financing.

Many of the informal or squatter settlements lack authorization, land ownership, public rights of way, public services, and reasonable access. Incomes are low, living conditions are harsh, and illness and disease are widespread. Conventional water and wastewater technologies are at least inefficient under these conditions, and may be completely unfeasible. New approaches are clearly needed.

Advances in hydraulic theory and technology, as well as experience, have provided the basis for modifications in the standards governing certain design parameters for conventional sewerage. The result has been a variety of sewerage systems that provide service levels similar to those of conventional sewerage at a fraction of the cost (Wright and Bakalian, 1990a). Some examples include flat gradient sewerage using smaller-diameter pipes; condominial sewerage; and other modifications to minimum depth, minimum slopes, minimum diameters of pipes, and the spacing and location of manholes. Solids-free sewerage (also known as small-bore sewerage) uses an interceptor tank to retain solids (Wright and Bakalian, 1990b). The tank is located between the house sewers and the rest of the system and allows flatter slopes and smaller diameters for sewer pipes. The key question for these and other alternatives is whether the lower capital costs would be offset by higher costs from operation and maintenance of the system. The suitability of alternative sewer systems needs to be demonstrated on a case-by-case basis for high-density urban areas.

Consideration should be given to the development of strategies that foster continuous incremental improvements in the provision of water supply and wastewater services, especially for the poorly served communities within the metropolitan region. Planning should consider the local ability to finance, operate, and maintain the system; the potential for building institutional capacity; the need to upgrade systems to accommodate future population growth; and the community’s long-term vision of a high-performance system. As discussed earlier, planning for drinking water and wastewater services should be well integrated with other health and nutritional programs.

The effective application of technology depends on the existence of carefully considered performance criteria that are appropriate to the megacities of the developing world. The continued use of effluent discharge standards borrowed from industrialized countries may hinder, rather than promote, meaningful innovation. Many of these standards simply reflect the capability of conventional technology rather than the needs of a particular environment or population. Adoption of such standards effectively precludes consideration of novel applications of technology, since the latter approaches will not necessarily produce the same results as conventional processes. An alternative is to apply performance criteria,

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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which describe the desired effects on human health (reduced exposure to pathogens), the environment (ecosystems to be protected), and human activity (human uses of the environment).

Most industrialized countries rely on technology-based standards rather than performance criteria. A critique of U.S. policy has indicated that this approach effectively discourages technological innovation, does not allow for regional differences, and has prevented the development of cost-effective water quality management programs (National Research Council, 1993a). On the other hand, the development and implementation of technology-based standards require less institutional competence than most alternatives. It is important that developing countries consider the pros and cons of any regulatory approach, rather than simply following the lead of industrialized countries.

It must also be remembered that many megacities are especially vulnerable to natural hazards, such as floods, earthquakes, and high winds. The larger and more unplanned the city, the more difficult it is to organize rescue and respond to disaster. In the event of a natural disaster, the water and wastewater infrastructures are susceptible to blockage and rupture. The result can be contamination of water supplies and the spread of infectious disease. Thus planning for natural hazards should be part of any program to improve water and wastewater services (Institute of Civil Engineers, 1995).

Given the right incentives, the private sector can often respond by creating new technologies that meet the needs and opportunities of megacities. In Japan, the private sector is creating and installing a new generation of technologies for water and wastewater treatment in smaller rural communities. The availability of capital in Japan has permitted joint government-industry efforts to research and develop new technologies, such as hybrid treatment reactors (combined activated sludge and biofilm), anaerobic treatment processes, and microaerobic processes (Rittmann, 1996). Based on anticipated growth, the influx of capital, and the potential to enter the large Asian market, a French consortium is developing sophisticated drinking water technology for Macau, near Hong Kong.

Unfortunately, the poorest megacities may not receive this kind of attention from the private sector because their consumer markets are less certain. The World Bank is experimenting with private sector involvement under difficult economic circumstances, and has reported progress in such places as the Republic of Guinea and the City of Abidjan, as mentioned in the preceding section (World Bank, 1994). Chile has passed legislation to decentralize the water sector and has changed incentives to encourage privatization (Lauria, 1993). The private sector is stimulated to develop and apply new technologies when there is a demand of adequate size and constancy. Additionally, regulatory or administrative barriers to new technologies must be minimized, and the need of the private sector to generate a return on investment must be accepted.

There are many other examples of technology innovation that may be useful for megacities in specific situations. These include low-cost water hook-ups, automated and remote meter reading, and low-cost materials and technology for neighborhood water and sewer systems. The use of water to carry away human wastes could, in some situations, be

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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replaced by nonwater options, such as the use of dry toilets and composting of wastes for agricultural or garden applications. 2

The sustainability of innovative water, wastewater, and other sanitation projects will depend on the availability of indigenous human resources, as well as financial capital. The cadre of technical experts in the developing world needs to be expanded. Such experts are especially important for merging specialized knowledge with local conditions, experience, and financial realities. They must be skilled as facilitators and able to handle the ambiguity of human decision making, as well as the discipline of technical information. Local experts are also needed to evaluate the suitability of technology that may be offered and promoted by private concerns through sophisticated marketing strategies.

Water Conservation and Reuse

Effective water resource management requires a holistic approach that considers an entire watershed or catchment area relative to water quantity, quality, and use.

Water is a renewable resource that should be managed so that future generations can obtain the same benefits as those enjoyed by current users. Such a resource should have a future value that is, on average, not less than its value today.

Water resources are complex systems serving many users in different ways. This is particularly true for surface water resources. Surface waters provide fish and wildlife habitats, supply water to humans and human activities, and support the movement of goods and people. Achieving sustainability requires that each use of a resource be evaluated in the context of all other uses and stresses, and that no use be permitted which adversely affects the capability to support future uses. It also requires institutions that can implement effective laws and regulations.

Current surface water withdrawals may or may not have an impact on future use, but ground water withdrawals frequently do. A lack of control over industrial waste discharge and a lack of wastewater treatment invariably threaten the sustainability of surface and ground water resources. Too often, the surface waters are grossly polluted and unsuitable for any use except as a sink for more waste. Ambient water quality standards that are reasonable and appropriate to local environmental, social, economic, and cultural conditions need to be established and enforced (see National Research Council, 1993a).

Ground water is a far more important resource than is often realized. Excluding the water locked in glaciers and icecaps, about 97 percent of the world’s fresh water is ground water, while streams, rivers, and lakes hold only about 3 percent (Bouwer, 1978). The potential for human pathogens and toxic contaminants to leach into ground water depends on

2  

Note that this paper is not meant to provide an assessment of technology options, but merely to highlight their potential importance.

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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many factors, such as the composition of soils and geologic materials, the depth of the water table, the recharge rate, and environmental factors that can influence the mobility or degradation of contaminants (National Research Council, 1993b). Once ground water has become contaminated, the prospects for remediation are uncertain and expensive. Moreover, remediation may require long time periods (in some cases centuries) because of the complex properties of the subsurface environment and the complex behavior of contaminants (National Research Council, 1994a). In-situ bioremediation is a technology that is gaining momentum, but careful evaluation is necessary to determine whether it works (National Research Council, 1993c). Moreover, the costs of remediation are high. The potential cost of ground water remedial activities in the United States may be as large as $750 billion in 1993 dollars over the next 20 to 30 years (National Research Council, 1993b). Thus comprehensive ground water research, monitoring, and protection programs will be cost-effective investments in sustainability (e.g., see National Research Council, 1993b; National Research Council, 1995).

To identify multiple-use and temporal conflicts in water resource allocation, it is necessary to take an integrated approach to the planning and management of the resource, and where appropriate, within a defined watershed or catchment area (see National Research Council, 1993a). Planning must consider all activities, present and future, within that region. Integrated management can be understood to address two outcomes: (1) the systematic allocation of resource services among competing users in the same time period, and (2) the consequences of that allocation for future availability and allocation of resource service flows. The criteria governing the first outcome typically include such things as economic efficiency, equity, fairness, and existing property rights. The second outcome addresses the issue of sustainability and fairness to future generations.

Conservation of water resources should be a priority for all megacities, not only those that are located in arid or semiarid climates. In many megacities, a significant amount of water (reportedly 40 percent or more in some cases) leaks from the system or is otherwise unaccounted for because of poor metering, theft, or accounting errors. Together with proper maintenance and metering, water conservation requires changing people’s behavior through voluntary or involuntary demand management measures. Involuntary policy tools include water rationing, retrofitting of low-flow plumbing equipment, new construction codes, and water reuse regulations. Voluntary policy tools, in contrast, focus on the way people are charged for water and the use of public education campaigns. Voluntary tools have been less commonly utilized, but have the potential to be more cost-effective. The institution of appropriate water rates requires that users first be metered, which also reduces lost and unaccounted-for water. Tariff design must take into account the principles of cost recovery, demand (i.e., what people are willing to pay), fairness, and equity.

As cities grow, water for urban uses becomes increasingly valuable as compared with other uses, such as agriculture. Water transfers, frequently a major component of water resource management, can involve the diversion of water to a new location or a change in the type of water use. When water is viewed as a commodity, its allocation can be driven by market forces, and these forces can act to enhance the efficiency of its use. However, water markets cannot be expected to resemble more conventional markets for a variety of historical, cultural, and ethical reasons. As with any policy option, there are benefits and

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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costs. The recognition and protection of third-party interests are essential if water transfers are to meet their potential to satisfy new demands (National Research Council, 1992).

Another means of conserving a community’s potable water supply is the practice of water reuse, which involves reclaiming industrial or municipal wastewater for the many nonpotable urban uses in a city. In this sense, reclamation and reuse of municipal wastewater represents a significant source of water, one that will become increasingly cost-effective.

Nonpotable reuse applications for reclaimed municipal wastewater may include agricultural irrigation, ground water recharge (replenishment, salt water intrusion barrier, subsidence control), recreational uses (impoundments, lakes, fisheries, snowmaking), and general urban uses (fire protection, toilet flushing). Planning for new urban developments should consider the potential for incorporating water reuse in their design. The major public health concern associated with most uses of reclaimed water centers around infectious agents and the possible spread of disease among the human population. However, the health risk will be minimal if the wastewater is properly treated prior to use. The characteristics of the source water and the intended use of the reclaimed wastewater dictate the type and degree of treatment that must be provided in reclaiming municipal wastewater for nonpotable reuse (see National Research Council, 1982, 1994b; U.S. Environmental Protection Agency, 1992).

Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Suggested Citation:"Water and Sanitation Services for Megacities in the Developing World." National Research Council. 1996. Meeting the Challenges of Megacities in the Developing World: A Collection of Working Papers. Washington, DC: The National Academies Press. doi: 10.17226/5267.
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Cities in developing countries are experiencing unprecedented population growth, which is exacerbating their already substantial problems in providing shelter and basic services. This volume draws on the significant advances in technologies and management strategies made in recent decades to suggest ways to improve urban life and services, especially for the poor. Four challenges to developing countries' megacities are addressed: labor markets, housing, water and sanitation, and transportation, along with a synthesis of general thinking on how to meet megacity challenges and be competitive in the twenty-first century.

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