We use water for drinking, cooking, bathing and general cleaning purposes. A supply of clean water freshwater, free of pathogens, is therefore a necessity. We obtain this supply of fresh water from the following sources:
• rainwater ;
• surface water from streams, rivers and lakes; and
• subsoil water from springs and wells.
In rural areas , water is obtained directly from the rain, streams, rivers, lakes , wells and boreholes. This is why villages are often sited near rivers and streams. It is important to protect these sources of water from contamination by human and agricultural wastes.
In urban areas, water is collected from natural sources purified and distributed to the people through a system of pipes by the public health authorities.
Rain water :
In countries where streams and wells are scarce, rainwater is collected in underground tanks and used. To keep out the dust particles , a sieve is fixed to the funnel through which the rain is collected. This sieve should be cleaned periodically. water f from the tank should be pumped out through a pipe, and not obtained by using a bucket toed to a rope.
Spring water :
Spring water is a good source of domestic water as it is free of impurities. To protect this water supply, a concrete wall is built around the spring so that the people have no direct access to it. The spring water is collected to a tank via a pipe leading form the springs. Taps are used to draw water from the tank. There should also be a pipe through which excess water from the tank can flow out.
Rivers and streams:
A river or stream that is used as a water supply in a village should be protected and used in the following way:
• the banks of the river should be kept clean
• refuse, and human and animal wastes should not be dumped in to the river.
• a concrete wall should be built across the river to divide it into an upper and a lower portion.
(I) the lower part of the river should be used for general washing and cleaning purposes.
(ii) No one should be allowed to use the upper portion of the river. Water from this portion should be collected in a tank by means of a pipe. The water should pass through a filter before it enters the tank. The filter must be cleaned periodically. This water can be used for drinking and cooking.
Drinking water must always be boiled. Surplus water from the tanks should be channeled back to the river.
Wells :
When a hole is dug below the level of the water table, ground water seeps into the hole to form a well. wells are important as a source of water in many rural areas the amount of water in wells fluctuates with the water table. A surface r well may run dry during the dry season, while a deep well will have water most of the year. Water in surface wells comes from the immediate surrounding near the surface and subsoil and so is likely to be contaminated with human wastes. Deep wells extend beyond the first layer of non porous rock to tap the water beneath this layer. Water from s properly built deep well is safe to drink as it is well filtered and free of pathogens.
Wells must always be sited away from latrines and rubbish dumps, and Aldo be at a higher level than these places.
The following measures should be taken to protect the water supply in a well
• the wells should be fitted with a proper cover.
• the inside of a surface should be lined with concrete of brick at least as far down ad the first layer of clay. In a deep well, the lining should extend up to the first nonporous layer of rock. This prevents the unsafe surface and subsoil water from mixing the safe ester below the nonporous layer. The concrete or brick lining should come up above the ground, to prevent any water that is spilt around thr well from the flowing back into it. The area around the well should have a concrete floor that slopes away from the well.
• the water should be pumped out into a nearby tank. If there is no pump, a clean bucket attached to the well should be used up for drawing up water. No one should use their own buckets for drawing up water.
Boreholes :
Many people in arid regions depend on boreholes for their water supply. Boreholes tap underground reservoir of water. They are very deep , usually going down to a depth if about 100 metres. Water is usually pumped out BH powerful machine at a rage of about 25,000 litres an hour. The water is stored in a huge tank, usually sited at the highest point in the village. Water from this tank is supplied to the people through pipes.
Water for domestic use :
Water for household use, especially for drinking and cooking should
• be free of pathogenic organisms,
•be cleat and free of suspended matter,
• have no unpleasant smell, and
• be tasteless.
Water from natural sources, especially shallow wells and rivers, must be purified before they can be used for domestic purposes. This can be done by
• boiling water for about 20 minutes to kill pathogens and their eggs and spores,
• cooling it, and then
• filtering it to remove suspended matter.
If commercial porcelain filters are not available, we can easily make a sand filter. It consist of barrel or tank filled with layers of clean stones, gravel and sand to a depth of 60 centimeters, constituting a filter bed. A tube is water added at the top of the filter bed. The water filters through the bed and flows out of the tube into a collecting vessel.
Note : Water can also be made by safe BG adding chlorine tablets (a germicide) instead of boiling. Care must be taken to add the correct amount of chlorine.
Purified water should be stored in covered enamel or earthen pots which should be washed regularly.
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