Water gets contaminated by the addition of:
(i) Agricultural chemicals: Farmers use excessive amounts of pesticides and fertilizers to increase crop production. These chemicals get carried away to the water bodies due to rains and floods which lead to water pollution.
(ii) Industrial wastes: Industries release harmful chemical wastes into water sources, thereby polluting them.
(iii) Sewage wastes: Waste materials from kitchens, toilets, and laundry sources are also responsible for contaminating water.