by Tinashe Madava
This is the last in a four-part series on water based on the book, Water in Southern Africa, published by SADC, IUCN and SARDC in February 1997.
The major sources of water pollution in the Southern African Development Community (SADC) countries are industrial and municipal waste, agrochemical pollution from the application of pesticides and herbicides, oil spills and industrial emissions, says a new book on water in southern Africa.
Water in Southern Africa says that “Economic growth leads to larger discharges of waste water and solid waste per capita”. The book explains that the high levels of pollutants from agriculture, industry and households in southern Africa have resulted in the inability of river systems to effectively cleanse themselves.
Fisheries, agriculture, transport and industry all depend on water for production, distribution and consumption yet they have often been found to be the major polluters of water.
Water in Southern Africa, a collaborative effort of the Southern African Development Community’s
Environment and Land Management Sector (SADC-ELMS), the regional Office for Southern Africa of the World Conservation Union (IUCN-ROSA), and the Southern African Research and Documentation
Centre (SARDC), calls on all water users in the region to cooperate in the smooth management of this finite resource, by placing water at the centre of all forms of life.
“From the beginning, water has been central to life. Human cultures, nourished by water, flourished or decayed according to available water for drinking, cultivation and navigation,” says the book, calling for clear cut policies on water management in the region to avoid destruction of whole ecosystems from pollution.
More often the poor, who do not have any means of purifying their drinking water, are affected by water pollution from industries like agriculture, mining and tourism. Water pollution results in various water borne diseases affecting the poor most, hence the need to protect the region’s water resources.
“It is therefore not surprising that water has been described as the single most important resource for our future and the pivot on which all future development depends.”
Rain is of economic importance, particularly to agriculture, which accounts for about 90 percent of the water demand in the region. However, the quality of rain reflects broadly the state of atmospheric pollution in the region.
One of the more damaging products of air pollution is acid rain. ,. It is the result of sulphur dioxide which is set free in the atmosphere where it dissolves in the moisture to form sulphuric acid.” It destroys the region’s soils, plants, and forests lakes and rivers are acidified.
Examples of sources of sulphur emissions to the atmosphere in the region are the copper/nickel smelters in Selebi Phikwe in Botswana, the Tsumeb in Namibia and the coal-fired stations in the Eastern Transvaal Highveld in South Africa.
“While the rainy season provides water to dilute pollutants, flooding from intense rains can make pollution worse,” says Water in Southern Africa. The book explains that storm water dissolves pollutants on the ground and carry them into water supplies, making the water unsuitable for consumption, as in the case of Goreangab in Windhoek, Namibia.
Manufacturing and service industries are primary sources or pollutants which can impair the reproduction of fish, retard their growth, or kill them as happened recently in Zimbabwe’s city of Harare where thousands or fish died from industrial pollution and sewage discharges.
The book asserts that pulp and paper mills as well as textile factories are among the worst industrial polluters in southern Africa. In Swaziland, paper fibres have been discharged into the Ushushwana river together with the effluent, and now carpet the bottom of the river where their rotting robs the water of oxygen, decreasing the survival of marine life.
Untreated sewage combined with industrial wastes are polluting coastal waters near cities, such as Maputo, along the entire coast of eastern and southern Africa. The book therefore calls on the region’s authorities to strongly enforce laws that guard against the further degradation of this essential resource.
So precious is water that its contamination has far reaching repercussions, affecting all living matter.
Scientists have revealed that high levels or nitrates (fertilisers) in drinking water can cause miscarriages in pregnant women and blood poisoning in young children.
Pesticides such as dichloro-diphenyl-trichloroethane (DDT), and aldrin, which are often used to control organisms such as snails, blackflies and mosquitoes, are washed into rivers and lakes where they end up killing fish and birds.
The effects of pesticide pollution on aquatic life are now becoming apparent in Mozambique where fish have been found dead in the Limpopo river after the spraying of an insecticide near the river. Traces of
DDT which is used to control mosquitoes in Zimbabwe have been found in the breast milk of women living along the Zambezi river.
Water pollution in southern Africa is therefore a result of poor management and enforcement of pollution legislation. Policies for the protection and management of living aquatic resources should be prioritised as the region’s environment suffers from pollutants discharged deliberately into the water bodies.
The book, Water in Southern Africa urges the southern African countries to unite in developing a comprehensive set of effective regional policies to discourage water pollution to protect the world’s widely shared resource- that which holds the key to life on earth-water. (SARDC)
