Water is one of the core essential and basic necessity; 1) for the life forms-living things on the biosphere, 2) for the natural processes, 3) for the communities, 4) for the society, 5) for the economy of the country and 6) for on-coming generations. Although total earth’s water (>71%) is constant, it goes through continuous hydrological cycle such as transpiring by vegetation, evaporation, precipitation, runoff, infiltration and other natural processes. Consequently, the rainfall in any locations may not be same and therefore water shortage is the final outcome. Despite earth’s majority of the cover is filled by water (97% by oceans), only freshwater (about 3% in which 85% is available as a glacier) is suitable for living organisms including humans. In recent years water table is facing serious threat due to rapid population increase, industrial and urban development, over usage, climate change, global warming, shrinkage in glaciers in Arctic and Antarctic, natural calamities (shifting of precipitation and reduced snow pack) and negligence of people to use the water in proper way and slow replenishment of natural waters .