HOW PEOPLE AFFECT OUR WATER QUALITY
Informal settlements
The constant rise in the number of people who live in the areas around streams and other water sources has placed an increasing pressure on this scarce resource. Because they do not have access to treated water in many of the areas, people use the river for washing and bathing. Also, when latrines are placed on the banks of the river, human faeces can contaminate the water. This gives rise to water-borne diseases such as cholera, gastro-enteritis, hepatitis, dysentery and typhoid. .
Agriculture
Water quality can be affected when farmers spray their crops with chemical pesticides and hormonal chemicals. These chemicals can seep into the ground water and eventually flow into streams and rivers.
Overgrazing occurs when too many animals are kept in an area which is too small to sustain them. The animals eat all the plants, which means that there is no ground cover left to bind the soil. When heavy rains fall on overgrazed lands, the rich top soil in which plants grow is washed away into rivers.
Domestic animals such as cows, goats and sheep can also contaminate water with their faeces. Also, when animals are allowed to wade in water, they disturb the river bed and the water becomes dirty.
Wetland destruction
Wetlands are the 'sponges' of the river system and are found at intervals along the entire length of the river. They absorb and store large quantities of water after it has rained, and then slowly feed the ground water and streams during drier times. By changing the course of rivers through the building of farm dams and channels or by interfering with the ecology of the wetlands, these important areas can dry up. This means fewer and fewer wetlands are left to act as natural filters and sponges for river water.
Commercial forestry
Planting of exotic trees in large numbers can be a drain on the water supplies in the area. Pine trees, for example, can each absorb about 200 litres of water a day. Therefore, planting forests near wetlands and streams can result in the water flow being restricted and eventually drying up.
Littering
Rubbish like plastic bags, bottles, paper and tins which are carelessly thrown on the ground in the city or in the country can cause pollution of the rivers. Rubbish is blown by the wind into the river or it is washed down storm-water drains and into the rivers.
Oil/chemicals/medicine
Pouring oil from motor cars or cooking oil into the drain causes serious problems in the rivers and at the water purification works. Chemicals, medicines and oil should never be flushed down the toilet or poured down the sink or drain, as they contaminate the water and make it costlier to treat. These products should be taken to a depot which can dispose of them in the correct way.
Industry
Some industries have been given permission to discharge their effluent into nearby streams. Umgeni Water first tests the effluent to ensure that it will not damage the environment. However, there are some industries which do not adhere to the standards set or which have not obtained permission to discharge into the river. Where necessary, those companies which pollute the river are prosecuted, but by then it is usually too late and the damage to the water has already been done.
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