Significance of indirect methods in accelerated execution of hydroelectric project investigations

Development of hydropower schemes involving large structures demand initiation of a well-considered programme of investigation that would provide sufficient information, especially about the status of the subsurface condition towards facilitating, site selection, feasibility evaluation, planning, establishing safe, economic execution of project and its operation. Indirect methods or non destructive methods of investigation are an efficient tool for the pre and post construction investigations. The merit of this low cost aid lies in its rapidity in providing a reliable profile of the subsurface over a large aerial extent. This paper describes the general Non destructive methods of investigation applied for Hydroelectric Projects such as Seismic Refraction Survey, Electrical Resistivity Survey, Ground Probing radar, Cross Hole Tomography, Underwater Scanning Using ROV etc.