Water

Water is one of the most indispensable resources and is the elixir of life. Life is not possible on this planet without water. It acts as a medium for both chemical and biochemical reactions and also as an internal and external medium for several organisms. Early human civilizations centered on the banks of the river. Many civilizations that flourished after developing a reliable water supply collapsed when the supply was exhausted or its quality deteriorated. Water, a natural resource which has been used for different purposes, namely for drinking, irrigation, industrial and others, mainly depends on its intrinsic quality of water resources available in the region. Surface water is highly valued because of a considerable quantity of fresh water. Peoples around the world have used surface water as a source of drinking water, and even today more than half of the world's population depends on surface water for survival.