ASSESSMENT OF ENVIRONMENTAL FLOW REQUIREMENTS IN DOWNSTREAM OF THE HYDROPOWER PROJECTS USING DIFFERENT TECHNIQUES

The Environment Impact Assessment is a decision-making tool and formal study process used to predict the ecological consequences of any development project and its environmental management. The main source of power production in Himachal Pradesh is hydroelectricity. The Beas River with a length of 470kms flows from Rohtang in Manali to meet the Sutlej River in Punjab has an identified hydropower potential of 6000MW. To tap this potential, the Himachal Government has already constructed many projects in the Beas River basin. This implies that the river bed could be dry during the summer period or lean period. Hence there may arise a situation in which the ecosystem can’t be able to sustain the riverbed ecology and riparian environment due to its case. The inability to maintain minimal flows may prompt the weakening of the subordinate ecosystem’s water condition. The general term used to depict the flow that is necessary to maintain the river ecosystem’s feature is minimum flow. Therefore, there has been a greater need to evaluate the requirements of the Environmental (Protection) Act, 1986; 15% of the minimum observed the flow of the stream has to be released, to the downstream of the diversion structure for the protection of flora, fauna, and aquatic life between intake and confluence point of tailrace and the stream as per the NGT order.