Water is a precious resource. It is like an elixir for life. Without water the survival of living organisms cannot be imagined. Water is found in solid, liquid and gaseous states. About 97 % water of surface water is found in oceans and sea as salty water. About 3 % of surface water is present as fresh surface water. But, that too is not accessible. We have only 1 % water available for human consumption. So, the judicious use of water is imperative.