Water is the most valuable resources of nature. This is renewable and inexhaustible resource but is in trouble these days. Demand of water has been increasing continuously its supply decreasing.
If we look at the water resources of India in the global context, India has 4 percent water whereas she is housing 16 percent of the world’s population. It means the per capita availability of water is quite low in our country. India ranks first in the world in irrigated area.
One-eighth area of the country is flood prone and one-sixth area is under the grip of drought. Nature of monsoon is mostly responsible for this. Food grains and other agricultural products are required in large quantity for the growing population. For this reason the use of water for irrigation of crops has been increasing.
The demand for water has increased in the cities due to rapid urbanization, industrialization, and modernization. In addition, the demand for water has been increasing for sewerage and for removing all kinds of wastes.