Table of contents

Water for Health - Taking Charge
2. Why we need to act

Pressures Are Getting Worse

The treatment of wastewater often is a haphazard affair. In developing regions of the world, treatment is applied in only a minority of systems. Even in the industrialized countries of North America and Europe, for example, sewage is not universally treated.

Problems of unsafe water and inadequate sanitation systems are most acute in developing countries. Although in a smaller proportion, people in industrialized countries also get sick from contaminated water and untreated sewage. Despite the fact that developed countries normally have the means to deal with these problems, they often don't for reasons of complacency, lack of political will, cost and so on. Public pressure to remedy serious health and environmental problems may be instrumental in initiating change.

Pressures Are Getting Worse

Unsustainable approaches : Some of the technologies adopted in the wealthier countries to make life easier and more comfortable for their inhabitants can cause problems. The move from latrines and septic tanks to flush toilets in major cities propels municipal sewage, often with limited treatment, into rivers and coastal areas. If all goes well, the waste may be diluted and treated by natural processes. But, it also may accumulate in fish and shellfish which, if eaten, can make people sick. Furthermore, the contaminated water may endanger the health of swimmers at beach-side resorts. Governments increasingly are forced to balance the costs of cleaning up sewage-polluted water against the loss of revenue that may result from ill-health, lost tourism and problems incurred by fisheries.

Urbanization: Cities are growing at an incredible rate worldwide. The current urban population of 2.8 billion people will increase to 3.8 billion in 2015 and to 4.5 billion in 2025. Megacities create tremendous demand for water and act as dense sources of pollution. This challenges the ability of those in charge of water management to provide for the needs of all inhabitants.

Population: With population growth, demand for the world's finite supply of fresh water is rising, putting strains even on the industrialized countries. Global population projections suggest that the world population of over 6 billion in 2000 will increase 20% to over 7 billion by 2015, and to 7.8 billion by 2025, a 30% rise. Enormous strains will be put on existing services, and substantial increases in the provision of water and sanitation will be needed to meet the needs of the swelling population. As populations grow and demands for water and other services expand, pollution levels will rise, while more water will be needed in agriculture to feed and nourish the large population.

Interdependence: Health is often not systematically considered by those who plan water development projects. Consequently, local communities, many of whom do not even stand to gain from the project, end up carrying the increased risk of illness from newly introduced water-related diseases. There are far too many examples of poorly-designed development schemes which have brought malaria or schistosomiasis into areas where it previously did not exist. Health concerns are rarely included in agricultural development policies. It has been shown that where health is taken into account, the eventual efficiency of water projects is greatly enhanced.

In Indonesia, the transmission of malaria was drastically reduced when farmers synchronized their rice-production system to allow rice paddies to dry out completely during certain periods. Then again, in Sri Lanka, the breeding of malaria mosquitos was suppressed in small rivers and irrigation canals by regularly flushing them out.

Fresh water: The world's supply of fresh water is limited. Water sources are vulnerable, too often ill-managed and inequitably distributed between the rich and the poor. The poor are also disadvantaged in that too many of them live in water-deficient countries, mostly in Asia, the Middle East and sub-Saharan Africa. This creates particular problems for people in rural parts of Africa where, on average, less than 50% of people have access to both improved drinking-water and sanitation.

Climate change: The 21st century could see a rise in disease if predictions of climate change come true. If nothing is done to reduce the emissions of carbon dioxide and other greenhouse gases which are believed to lead to global warming, scientists warn that global temperatures might increase by 1 to 3.5 degrees centigrade by the year 2100. Scientists believe that the climate changes would increase the number of deaths and illnesses due to infectious diseases. For instance, mosquitos may extend their range to new geographical areas, leading to more cases of malaria. Climate change also would threaten hundreds of millions of people, who currently are not at risk, with dengue (another mosquito-borne disease), and floods and drought would impact on food production.

Natural disasters : Floods are the second most frequent cause of natural disaster, after windstorms. However, drought is the largest cause of death because it often leads to famine. Floods affect more regions and more people than any other phenomenon. The consequences of flooding, especially in poor communities, can be horrific. This was seen in the disastrous floods that occurred in the aftermath of the powerful cyclones that struck Madagascar and Mozambique in February 2000. Many people died, hundreds of thousands of people were made homeless, epidemics of malaria and cholera broke out, rich farmland was rendered useless and economic development received a severe setback.

Major Floods and Storms Floods devastate people and structures Year Location Deaths 1421 Holland 100 000 1530 Holland 400 000 1642 China 300 000 1887 Yellow river, China 900 000 1900 Galveston, Texas, USA 5 000 1911 Yangtze River, China 100 000 1931 Yangtze River, China 145 000 1935 Yangtze River, China 142 000 1938 Yellow river, China 870 000 1949 Yangtze River, China 5 700 1953 Holland 2 000 1954 Yangtze River, China 30 000 1959 Japan 5 098 1960 Bangladesh 10 000 1963 Vaiont, Italy 1 800 1979 Morvi, India 15 000 1991 Bangladesh 139 000 1991 Huai River, China 2 900 1998 Central America 18 000 1998 Yangtze River, China 3 000 1998 India and Bangladesh 2 425 Source: White 1999: World Water Vision 2000

The after-effects of a major flood usually linger on for many years. Flood-stricken communities have to come to terms with the drownings and injuries sustained by their loved-ones, with the loss of their homes and belongings. The breakdown of water and sanitation services increases vulnerability to waterborne diseases. Flood damage sustained by water supply, irrigation and other water infrastructure is a major setback to health and economic development. Environmental pollution leads to more ill-health. For instance, leptospirosis, a bacterial disease which affects both humans and animals, can reach epidemic proportions during severe flooding because of the widespread contamination of surface water, soil and plants.

Contaminated water causes 54 deaths in Milwaukee Cryptosporidium parvum was not recognized as a human pathogen until late in the 1970s. In the early spring of 1993, the residents of Milwaukee, Wisconsin, fell victim to the largest documented outbreak of waterborne disease in the USA. More than 400 000 people fell ill with acute watery diarrhoea caused by Cryptosporidium infection. The infection, which causes abdominal cramping, nausea, vomiting and fever was transmitted through the public water-supply system. Milwaukee gets its water from Lake Michigan. Apparently, one of the city's water treatment plants failed to filter out the dangerous parasite in the untreated water. Two years after this outbreak, investigators concluded that the infection, which can have fatal consequences for immunodeficient people, had killed 54 - most of whom had AIDS. Source: MacKenzie et. al., 1994

3. Where we need to act