Excavation & lining of Intake shaft & Approach Channel was done in the bed of already existing Mettur reservoir. Horse-shoe shaped pressure tunnel, Surge Shaft, Penstock Tunnels, concreting of breast walls, piers & gantry for control gates was done, on rock strata of granite

Pressure Tunnel 13.7m. dia., 376m. long Horse Shoe Shape
Surge Shaft 50m. dia., 64m. long semi Circular
Penstock Tunnel 6.7m. dia., 90m. long circular
Underground excavation 6,00,000 cu.m.
Concrete lining 80,000 cu.m.