123. Need for Development of Hydropower and Dams in India Highlighting the associated Environmental Issues

India is fortunate to be endowed with all primary energy sources like coal, petroleum, lignite, hydropower, nuclear power, etc. However, among these, the hydropower is the only renewable source of energy and has been recognized to be economical and preferred source of electricity due to its various inherent benefits. Notwithstanding established preferences for hydropower and availability of vast hydro potential in the country, the pace of hydro development has so far been slow. The country presently needs greater hydropower generating capacity for the stability of its power system. Our country experience extremes of climate. Normally annual rainfall varies from less than 100 mm in western Rajasthan to over 11,000 mm at Cherapunji in the North-East. The annual average rainfall is of the order of 1170 mm which together with snow melt, etc., yields nearly 4000 km³ of water. After deducting for infiltration and evaporation the flood surface flow in the rivers of the country is estimated at 1896 km³. The constraint in exploitation the available water is that the major part of the flow occurs as floods during a short span of time and there are obvious limitations in storing the available water. Year after year India has been suffering floods and droughts with regular interval. Hence, the main challenge facing management of water resources, is how to maximize the positive impacts so as to ensure reliable water supply for irrigation, drinking water and for industrial consumption, etc., mitigate flood damages, ensure purity and reduce pollution of water and at the same time minimize the socio-ecological impacts such as water logging, salinity, pollution problems of settlement and rehabilitation etc. Because of uncertainty of the nature and huge demand for water from all sources and also to attain self-sufficiency and security for water, food and energy we have to pursue all options for integrated development of water resources including construction of dams. The environmental pollution is a serious threat now-a-days in our country. Therefore, in order to control pollution and simultaneously improve the power generation in the country we need to lay emphasis on the generation of a clean power which is only hydropower.