What are the main causes of water pollution? State three ways to control water pollution.

The main causes of water pollution are:

1. Chemical wastes from industrial and agricultural processes.
2. Thermal wastes from nuclear and thermal power plants.
3. Sewage and garbage disposed into water bodies.

It can be controlled by the following ways:

1. Domestic sewage should be treated before being discharged into water bodies.
2. Waste products of industries should be treated before being discharged into water bodies.
3. Use non-biodegradable materials such as detergents, pesticides and polythene responsibly to avoid pollution of water and the environment.