(i) Most important are the industrial effluents that are discharged into rivers. They are both organic and inorganic. Coal, dyes, pesticides, fertilisers, plastic are some common pollutants of water. Industrial wastes containing toxic metals pollute the water.
(ii) Suggestions to control water pollution:
(a) Water should be reused and recycled to maximise its usage.
(b) Rain water should be harvested to meet water requirements.
(c) Hot water and effluents should be treated before releasing in river and ponds.
(d) Overdrawing of ground water reserves by industry where there is a threat to ground water resources also need to be regulated legally.
