Bad water means bad health: A Study of the World's Water

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The percentage of people served with some form of improved water supply rose from 79% (4.1 billion) in 1990 to 82% (4.9 billion) in 2000. Over the same period, the proportion of the world's population with access to excreta disposal facilities increased from 55% (2.9 billion people served) to 60% (3.6 billion). At the beginning of 2000 one-sixth (1.1 billion people) of the world's population was without access to improved water supply and two-fifths (2.4 billion people) lacked access to improved sanitation. The majority of these people live in Asia and Africa, where fewer than one-half of all Asians have access to improved sanitation and two out of five Africans lack improved water supply.

Moreover, rural services still lag far behind urban services. Sanitation coverage in rural areas, for example, is less than half that in urban settings, even though 80% of those lacking adequate sanitation (2 billion people) live in rural areas - some 1.3 billion in China and India alone. These figures are all the more shocking because they reflect the results of at least twenty years of concerted effort and publicity to improve coverage. One positive finding of the Assessment 2000 is that sanitation coverage appears to be higher than would be expected from the findings of earlier assessments. This is because the consumer-based survey data in the Assessment 2000 account for households that provided their own sanitation facilities, especially in Asia and Africa. These facilities were not covered by the provider-based data used in previous assessments.

Although an enormous number of additional people gained access to services between 1990 and 2000, with approximately 816 million additional people gaining access to water supplies and 747 million additional people gaining access to sanitation facilities, the percentage increases in coverage appear modest because of global population growth during that time. Unlike urban and rural sanitation and rural water supply, for which the percentage coverage has increased, the percentage coverage for urban water supply appears to have decreased over the 1990s.

Furthermore, the numbers of people who lack access to water supply and sanitation services remained practically the same throughout the decade. The water supply and sanitation sector will face enormous challenges over the coming decades. The urban populations of Africa, Asia, Latin America, and the Caribbean are expected to increase dramatically. The African urban population is expected to more than double over the next 25 years, while that of Asia will almost double. The urban population of Latin America and the Caribbean is expected to increase by almost 50% over the same period.

Although the greatest increase in population will be in urban areas, the worst levels of coverage at present are in rural areas. In Africa, Asia, Latin America, and the Caribbean, rural coverage for sanitation is less than one-half that of urban areas. In those three regions alone, just fewer than 2 billion people in rural areas are without access to improved sanitation, and just fewer than 1 billion are without access to the improved water supply. This report uses international development targets to highlight the challenges faced by the sector in reducing the coverage gap. To achieve the 2015 target in Africa, Asia, Latin America, and the Caribbean alone, an additional 2.2 billion people will need access to sanitation and 1.5 billion will need access to water supply by that date.

In effect, this means providing water supply services to 280,000 people and sanitation facilities to 384,000 people every day for the next 15 years. Projected urban population growth, especially in Africa and Asia, suggests that urban services will face great challenges over the coming decades to meet fast-growing needs. At the same time, rural areas also face the daunting task of meeting the existing large service gap. To reach universal coverage by the year 2025, almost 3 billion people will need to be served with a water supply and more than 4 billion with sanitation. Poor water supply and sanitation have a high health toll, whereas improving water and sanitation brings valuable benefits to both social and economic development.

The simple act of washing hands with soap and water can reduce diarrhoeal disease transmission by one-third. Hygiene promotion, therefore, is an important priority. Africa has the lowest total water supply coverage of any region, with only 62% of the population having access to the improved water supply. This figure is based on estimates from countries that represent approximately 96% of Africa's total population. The situation is much worse in rural areas, where coverage is only 47%, compared with 85% coverage in urban areas. Sanitation coverage in Africa also is poor, with only Asia having lower coverage levels. Currently, only 60% of the total population in Africa has sanitation coverage, with coverage varying from 84% in urban areas to 45% in rural areas.

In global terms, the continent contains 28% of the world's population without access to the improved water supply. It also contains 13% of people without access to improved sanitation worldwide. It is predicted that Africa will face increased population growth over the coming decades, with the greatest increase coming in urban areas. As a result, approximately 210 million people in urban areas will need to be provided with access to water supply services, and 211 million people with sanitation services, if the international coverage targets for 2015 are to be met. A similar number of people in rural areas will also need to gain access.

Given the Assessment's findings concerning change in coverage over the 1990s, it appears that future needs for rural services may continue to be the most difficult to meet. Data representing 94% of the Asian population suggest that only 48% of the population has sanitation coverage, by far the lowest of any region of the world. The situation is even worse in rural areas, where only 31% of the population has improved sanitation, compared with 78% coverage in urban areas. Total water coverage in Asia is also the second-lowest, after Africa, at 81%. But again, water supply coverage is lower in rural areas (75%) compared with that in urban areas (93%). Because of the population sizes of China and India, along with other large nations in the region, Asia accounts for the vast majority of people in the world without access to improved services.

Eighty percent of the global population without access to improved sanitation, and almost two-thirds without access to improved water supply, live in Asia. At present, approximately one-third of the Asian population is urban and two-thirds live in rural areas. But this balance is predicted to shift over the coming decades. By the year 2015, the urban population is projected to be 45% of the region's total, and grow to just over one-half of the total Asian population by 2025. This population growth will place enormous strain on already over-burdened services, especially in urban centers.

To meet the international development target of halving the proportion of people without access to improved services by 2015, an additional 1.5 billion people in Asia will need access to sanitation facilities, while an additional 980 million will need access to the water supply. Coverage estimates based on data for 99% of the region's population, collected as part of the Assessment 2000, suggest that the region has relatively high service levels. For example, total coverage with water supply is approximately 85% of the population, while total sanitation coverage is slightly lower at 78%.

Large disparities are apparent between urban and rural areas, with an estimated 87% of the urban population having sanitation coverage, but only 49% of the rural population having coverage. For water supply, 93% of the urban population enjoys coverage, while only 62% of the rural population is covered. Part of these discrepancies may be due to local definitions of "safe" or "improved" service. For example, some countries in the region, for which household surveys were not conducted, may have used higher standards when defining services. In these cases, the coverage figures may be underestimated. A total of 78 million people are without access to improved water supply in the region. In comparison, 117 million people are reported to be without access to improved sanitation services. The vast majority of these people live in South America.

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