Coastal reservoir strategy to enhance India's freshwater storage by impounding river flood waters: a detailed overview

Abstract

Abstract This paper revisits the water resource scenario in India and presents the adequacy of the coastal reservoir concept to address water scarcity by impounding excess river flood waters. Although there has been no significant change in India's rainfall pattern in the last 100 years, there is a spatial non-uniformity in the rainfall events that occur which makes it difficult to pre-plan large-scale water storage at different locations. This study highlights the fact that there is enough water available but the deficiency is in storage. A large portion of freshwater from river systems, groundwater and wetlands drains into the sea due to insufficient storage facilities. Coastal reservoirs enable the storage of excess river flood waters near the coast for future use. This paper discusses current water supply solutions available in the country, and the efficacy of coastal reservoirs along with feasibility implications. The associated rewards and challenges are also discussed. The paper presents details of existing coastal reservoirs worldwide and recent feasibility studies envisaging coastal reservoirs in India.