water has been the one essential co

water has been the one essential constant . Covering roughly seventy percent of the earth’s surface, only a mere fraction is available as freshwater and of that, an even smaller proportion is available for human use and we are only just beginning to truly understand the nature of this most precious and limited resource.


Water resources are sources of water that are useful or potentially useful. Uses of water include agricultural, industrial, household, recreational and environmental activities. The majority of human uses require fresh water.
97 percent of the water on the Earth is salt water and only three percent is fresh water; slightly over two thirds of this is frozen in glaciers and polar ice caps.[1] The remaining unfrozen freshwater is found mainly as groundwater, with only a small fraction present above ground or in the air.[2]