Executive Summary : | Multi-purpose reservoirs significantly impact socio-economic, hydrologic, and ecological conditions in river basins worldwide, including India. Simulation-optimization approaches are often used to identify operational strategies and design parameters for reservoirs. However, during multi-year droughts, reservoir models may fail to effectively simulate water supply due to unaccounted for climate impacts on crop water demands and human adaptation to demand deficits. This project aims to bridge the gap between socio-hydrology and reservoir optimization to better represent human elements in reservoir operations and simulate crop water demands during multi-year droughts. The project will focus on improving crop water demand estimation using a crop growth model, improving the representation of conjunctive use of surface and groundwater in the command area, and including water user's demand adaptation in events of persistent demand deficits from surface reservoirs during multi-year droughts. A baseline model for the reservoir and its command area will be set up based on physical hydrological principles and existing demand patterns. Crop models will be set up to understand changes in demands with climate. A multi-model framework will be used to build and test alternative representations of the reservoir and command area, validated using qualitative and quantitative data. Two large reservoirs in India, the Nagarjuna Sagar reservoir on Krishna river and the Upper Wardha dam on the Godavari river, will be studied to understand potential variations in human feedbacks and test the applicability of the multi-model framework. Adaptation options to manage future multi-year droughts will be evaluated. |