Among the essential elements for the existence of life, water is rated as the most important. Water is  a universal solvent and is largely responsible for determining the structure, function and distribution of species in an ecosystem.
The original source of water is precipitation from the atmosphere. Water on earth occurs in all three phases. As a liquid, it forms the hydrosphere. Around 75% of the earths surface is covered with hydrosphere.
The total amount of water on the earth’s surface is around 266 x 10E20 kg. Around 97% of water on the Earth is salt water, 2% is locked in polar ice -caps, mountains and glaciers and the remaining 1% is available as fresh water.
The production, development and efficient management of water resources for beneficial use is called water conservation. Listed below are a few techniques of water conservation.

1.                  Rainwater harvesting

2.                  Watershed management

3.                  Construction of storage reservoirs

4.                  Reuse of industrial wastewater and

5.                  Better agricultural practices