Question

how is the river water converted into potable water, for a city water supply system?

Answer 1

HEY MATE____________

In cities, drinking water supply from water works in water works the methods like sedimentation, decantation, loading ,filtration and chlorination, etc are used to remove undesirable materials from water.

THE purification of river water or Lake water is done in the following steps:€€

1.the water from a river or lake is formed by the pumping station into a large reservior called sedimentation tank. This water is allowed to stand in the sedementation tank for sometime full stop during this time, many of the insoluble substances present in water settle down at the bottom of the tank.

2. from the sedimentation tank, water is sent to a 'loading tank'. In the loading tank, some alum is added to water. The Heavy particles of dissolved alum deposit on the suspended clay particles in water.
In this way, the suspended clay particles in water get loaded with alum particles, become heavy and settle down at the bottom of the tank. thus, the process of loading by using alum removes suspended clay particles from water.

3.the water is then passed through a filtration tank. The filtration tank has three layers: fine sand layer at the top, coarse sand layer in the middle and gravel (tiny holes) as the bottom layer.
when water passes through the layer of sand and gravel, even the small suspended particles and other materials in water get removed.

4.The clear water is then passed into a chlorination tank..a little chlorine gas is added to water in this tank. Chlorine is added to water to kill the germs present in it. The water now becomes fit for drinking.

THANKS ___________@@@@@@bhargav....