EVALUATION OF OPERATION OF MAITHON AND PANCHET RESERVOIRS IN THE DAMODAR RIVER SYSTEM

Abstract

The most.important issue plaguing the reservoirs of Damodar Valley Corporation (DVC) is the reduction in capacity due to progressive sedimentation. Water utilization in terms of irrigation, municipal and industrial water supply, hydropower generation, etc., is done from the live storage of the two lower reservoirs, viz., Maithon and Panchet, which are 52 years and 50 years old respectively. So, reduction in live storage capacity of these two reservoirs is of utmost concern. Revised Capacity of the two lower reservoirs, viz., Maithon and Panchet, has been estimated, for various critical situations, using the Empirical Area Reduction Method as specified in IS 5477 (Part 2): 1994 (Reaffirmed 2004), the Indian Standard for Fixing the Capacities of Reservoirs—Methods (Part 2 Dead Storage), as this method is more reliable than the Area Increment Method. Routing of some of the major recorded floods, through Maithon and Panchet Reservoirs, has been carried out by the Level Pool Method, considering the latest available capacity in the two reservoirs. Presently, the Flood Management Operations in DVC are guided by the Slab Rules specified in the Regulation Manual for Damodar Valley Reservoirs (DVRR Manual), which stipulate certain maximum combined flood release from Maithon and Panchet Reservoirs corresponding to certain percentage of combined flood cushion occupied. Endeavour has been made to arrive at separate Slab Rule Policy for Maithon and Panchet Reservoirs. By comparing the Outflow Hydrographs as per the proposed Slab Rule Policy with the Actual Outflow Hydrographs following the. Slab Rules specified in the DVRR Manual, it was observed that the proposed Slab Rules are better able to attenuate the flood peaks.