*Director -
Former Executive Director,
Hydro electricity is the most widely used form of renewable energy, accounting for 16 percent of global electricity generation. The cost of hydroelectricity is relatively low, making it a competitive source of renewable electricity. The main structures in a hydro power project are dam, surface/underground caverns, hydraulic tunnels, canal, shaft etc. After construction, most of the underground civil structures of Hydro Power Projects suffer from seepage and leakage problems. The structures which suffer from seepage and leakage problems are: Underground caverns, Shafts, Dam galleries, Tunnel adits after charging, Canals and Power channels. Soon after charging water conductor system, underground structures like power house cavern, transformer cavern, cable shafts, power channel, dam galleries etc. show sign of seepage. Sometimes the seepage is large and uncontrollable. Seepage generally occurs from porous concrete from underground source when the surrounding hill mass is charged because of construction of a structure obstructing the original path of sub surface water flow. Leakage occurs from construction joints, contraction and expansion joints, cracks developed due to various reasons, settlement of foundations, crack in joint seals due to movement, cracks developed due to aging of concrete and deterioration due to chemical reaction etc. It is the leakage which is more harmful than seepage. The water seeping or leaking may have multiple effets on the structure like loss of water availability or creation of unsafe conditions in a power plant or may damage the equipment installed in the structure. In this paper some of the solutions to either prevent leakage and/or to divert the water properly to the drains have been discussed. Use of new materials to reduce and control the leakage has been presented.
