41. Simulation of Impact of Climate Change on the Performance of a Reservoir System in Eastern India

The work deals with the impact of changing climate on performance of DVC (Damodar Valley Corporation), reservoir system (Fig. 41.1) (comprising Tilaiya, Maithon, Konar and Panchet dams (multipurpose dams), Tenughat dam (single purpose) and Durgapur barrage on river Damodar of India using HEC-5, a simulation model for reservoir operation (developed by HEC, USA). The projected climate has been taken from projected climate output (A1B scenario) of Regional Climate Model PRECIS of Hadley Centre, UK prepared under IPCC (Intergovernmental Panel on Climate Change). Integrated operation and reservoir guide/ rule curve of DVC Authority was used from 1st of June (water year starting date in India) for a future period (2018–2024). Simulations were executed for 1985–1990 (baseline period) and for 2018–2024 (future period) with changed climate data (with current demand and projected demand). The system performance (on a seasonal basis) using “Performance Indices” (viz. volume reliability, time reliability, flood control index) for the future scenario (with current demand) became better than that for baseline condition in four seasons for Panchet reservoir. Reliability of meeting demands (M&I) in November and December in 2020 (with 58% increased projected inflow in comparison to baseline) with projected demand showed improvement (by 14%) over those in October and in months of January to May in 2020 at Maithon reservoir. It was noted that remarkably increased projected inflow (unseasonal) into the Panchet (by 1286.8%) and Maithon (by 1014.4%) reservoirs with reference to a baseline condition in March and May of 2022, respectively, caused flooding (unseasonal and high) downstream Panchet reservoir and bank full flow (unseasonal) downstream Maithon dam in March and May. The results from the study would guide concerned authorities for operating reservoirs for anticipated climate change.