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World Resources 1996-97 (A joint publication by The World Resource Institute, The United Nations Environment Programme, The United Nations Development Programme, and the World Bank) (Data edited by Dr. Róbinson Rojas)
5. Urban Priorities for Action PRIORITIES FOR ACTION: WATER AND SANITATION
Cities across the globe confront problems related to water supply and use. For many cities of the developing world, the top environmental priority remains improving access to clean water and sanitation. As the World Bank concluded in 1992, doing so would be the single most effective means of alleviating human distress (4). When services were improved in cities in developed countries in the 19th and 20th Centuries, health improved dramatically. (See Figure 5.1.) In both the developing and the developed world, there is also a critical need to use water more efficiently and to intensify efforts to stop the deterioration of aquatic environments caused by municipal and industrial effluents.
Improving Access to Water and Sanitation
Despite nearly $100 billion in investments, the International Drinking Water and Sanitation Decade of the 1980s fell far short of meeting its goal of water and sanitation for all (5). During the decade, the number of urban people in the developing world with access to adequate water increased by about 80 percent, and the number of urban people with adequate sanitation facilities increased by about 50 percent. The rapid rise in urban populations offsets these gains, however, and in 1994 more than 220 million urban dwellers (13 percent of the developing world's urban population)still did not have access to a safe and reliable water source, while more than 420 million (25 percent of the developing world's urban population)did not have access to sanitation services (6).
Although the Decade did not meet its goals, it did bring into focus the magnitude of the health problems associated with inadequate water and sanitation services and highlight the need to find new strategies to improve coverage. Indeed, the program's greatest achievement, by some counts, may have been the transformation in thinking that accompanied it (7) (8).
Broadly, four key lessons emerged from the Decade: first, systems should respond to local demands and should be as simple, sturdy, and inexpensive as possible; second, the involvement of the community and households--particularly women--in system design and maintenance is a crucial component to a project's success; third, governments need to improve the efficiency and sustainability of system operation and maintenance; and fourth, water should be treated as an economic commodity paid for by users (9).
Despite a surprising degree of consensus on these points, many governments and donor agencies have yet to move beyond rhetoric to implementation, according to some critics (10). Translating the lessons into practice poses many challenges (11). However, much progress is being made.
Adopting Appropriate Technology and Standards
The Decade made clear that the high-cost water and sanitation systems adopted throughout the developed world--with centralized systems built and maintained by subsidized public agencies--will not work in the developing world. The number of people unserved is far too great, and city coffers far too small, to provide all residents with piped water and flush toilets in their houses. Whereas some parts of a city, such as the urban core, may be covered by conventional sewerage, other areas, particularly low- income settlements on the urban periphery, would be much better served by lower-cost alternatives (12).
Evidence of the success of low-cost solutions can be found in cities around the world, from large-scale programs for pour-flush latrines or ventilated improved pit latrines to community groups implementing small-bore sewer schemes. Each solution is unique, tailored to local conditions and needs, but most rely on locally manufactured hardware (e.g., plumbing, sanitary sheds, or concrete caps for pit latrines)and the efforts of community members to install, maintain, and manage the systems (13). Systems using lower-level standard technologies can be effective and much less expensive, at only one tenth to one twentieth of the cost of a conventional sewage system. Most of the lowest-cost systems require far less water, and once they are installed can be upgraded gradually (14).
One of the greatest barriers to installing low-cost alternatives is political opposition to what is considered "low technology." In many developing countries, there is still a tendency on the part of governments and funding agencies to insist on standards that are higher than necessary, sometimes doubling the cost of service delivery (15). In Cartagena, Colombia, for example, officials proposed a conventional sewage system even though a high water table, impermeable soils, and land levels well below the city sewer mains caused pipes to sink and necessitated pumping wastewater uphill to city sewer mains. Once local officials were persuaded that the lower standards of technology were not "illegal," a system that uses a septic tank to remove biosolids and that transports liquid wastes in small-diameter pipes was installed at one third the cost of a conventional system. The system has been operating successfully for more than 10 years (16).
Condominial sewers have also proved to be a cost-effective alternative, and versions have been installed in low-income neighborhoods in northeast Brazil, Pakistan, and Yemen (17). Condominial sewers use a radically different layout, with smaller and shallower feeder sewers running from toilet to toilet through each backyard. The wastewater of an entire block discharges into the main trunk line at a single point rather than having to connect each house to the main trunk. (See Figure 5.2.)
The Orangi Pilot Project in Karachi, Pakistan, illustrates the successes possible with low-cost sanitation alternatives. The community adopted a sewage system that filters biosolids into a tank and therefore uses smaller pipes and flatter gradients in the streets. The system cost one tenth of what it would have cost to install conventional sewerage. Most of the funds were invested by the community; even now the tanks and sewers are paid for and managed by groups of households. The municipality is responsible only for the construction and maintenance of the main trunk drains (18) (19).
Low-cost systems are not foolproof, however. Most rely on the active participation of community members in maintaining the pipes. While this reduces the utility's operating costs, if the community and organizational aspects are missing, the technology will work poorly (20).
Involving the Community
Community involvement in water and sanitation projects is key to their success. Not only must communities be taught how to maintain and operate systems, they also must be consulted to determine what type of system best suits local conditions. Women, the major users of a system, can provide valuable advice about the design and management of a water and sanitation system. Failure to involve the community can lead to inefficient systems. In Nicaragua, for example, new latrines were not used by women because their feet could be seen from outside, denying them the customary privacy (21). In contrast, when women are taught to maintain handpumps or otherwise manage collective water systems, they often perform better than men because they are less likely to migrate, more accustomed to voluntary work, and can be better trusted to administer funds (22). Involving communities has other benefits as well, such as greater community acceptance of a new system and correspondingly increased willingness to pay for a system and help maintain it (23).
In Chinautla, an informal settlement in Guatemala City, Guatemala, community members asked the municipal water enterprise to install a single-source water tank, even though such units are typically used only temporarily. The community believed that this was the best solution to its water supply needs, and each family built its own pipe to the central source. The local community association receives one large bill from the water company, and one resident chosen by the community manages the billing and the collection of fees from each household. While the cost of the single-source water tank per family is more than for families directly connected to the city's water supply network, it is still far less than what they had been paying for water from private vendors. This system is being replicated in other settlements in Guatemala (24).
Improving Operation and Maintenance
National and international agencies have placed far too much emphasis on the construction of new facilities at the expense of improving operation and maintenance of existing installations (25). In Mexico City, for example, 50 percent (7 out of 14)of the wastewater plants are operated at less than their designed flow capacity and treat only about 7 percent of the city's total wastewater (26) (27). The generally poor performance of public water and sewage utilities in developing countries leaves ample room for improvement and is a major factor contributing to the high cost of these services (28).
In many cities, about half of the water that is treated and distributed at public expense is not accounted for. In Manila, Philippines, for instance, 58 percent of water is unaccounted for, as opposed to 8 percent in Singapore. For Latin America as a whole, such water losses cost between $1 billion and $1.5 billion in forgone revenue each year (29).
As much as one half of the water not accounted for is due to unrecorded usage or illegal taps. For example, in Caracas, Venezuela, approximately 30 percent of water connections are not registered (30). Reducing such losses is cheaper than reducing leakages, provided the utility has a sufficient number of trained staff. Major strategies include installing, promptly servicing, and recalibrating meters; updating and reviewing consumer records to estimate consumption when meters are unserviceable; and streamlining bureaucratic procedures to assist customers to make new legal connections.
Reductions in unaccounted-for water can allow investments in new works to be deferred or at least reduced in scope, with significant savings. In addition, by improving the system of meter reading and billing or by detecting and charging for illegal connections, revenue can be greatly increased to pay for water treatment and distribution as well as operation and maintenance. For example, in urban areas in Thailand in the 1980s, each 10 percent of unaccounted-for water saved was estimated to immediately generate an additional $8 million per year from the 3.5 million people served (31).
With better cost recovery, utilities in developing countries could improve the quality and availability of water, potentially even in low-income areas. Water supply projects require huge capital investments, yet cities are faced with decreases in funds for urban water supply purposes and burgeoning urban populations. In developing countries, consumers pay only about 35 percent of the costs of supplying water, according to a recent analysis of World Bankţfinanced projects (32). Recovering a greater percentage of these costs could provide city managers with funds to expand coverage in new areas or to maintain and improve existing facilities.
Drinking water, however, is a basic human need, and sufficient water for good hygiene is a prerequisite of public health. With these considerations in mind, governments have historically subsidized the cost of water. Unfortunately, these subsidies rarely reach the urban poor; instead, they most often benefit the better- off consumers with house connections. In many cases, the poor are actually paying more than their wealthier counterparts for less reliable service. Water from vendors costs substantially more (and may be of poorer quality)than piped water in the same areas. Indeed, the poor may pay as much as 30 percent of their income for water, while the well-to-do pay less than 2 percent (33).
Evidence exists that poor urban residents want and are willing to pay for on-plot--if not in-house--water supplies of reasonable reliability. Unlike some other environmental amenities that benefit the public at large, it is the individual household that receives most of the benefits of piped water. The prevailing assumption is that households are willing to pay about 3 to 5 percent of their income for access to clean water, yet actual studies reveal that some are willing to pay considerably more, some less (34) (35).
The 1980s saw a widespread commitment to adopting more cost- recovery programs, especially among donor organizations. Yet most cities still do not achieve full cost recovery in water supply operations, and equity concerns remain. There is no guarantee, for example, that a financially motivated utility will invest the additional funds in low-income neighborhoods rather than high- income suburbs. Furthermore, the debate concerning how much to charge and to whom and whether water supply tariffs should cover only operation and maintenance costs or should also generate resources for future investment is far from over.