Water is vital to life, maintenance of ecological balance, economic development,
and sustenance of civilization. Planning and management of water resources and its
optimal use are a matter of urgency for most countries of the world, and even more so for
India with a huge population. Growing population and expanding economic activities exert
increasing demands on water for varied needs — domestic, industrial, agricultural, power
generation, navigation, recreation, etc. In India, agriculture is the highest user of water.