An Integrated Hydrological Modeling Framework for Enhancing Water-Energy Nexus during El Niño Events in the Godavari River Basin, India

El Niño events pose a significant threat to water security in the Godavari river basin (GRB), leading to adverse impacts on water-energy nexus. To enhance long-term energy security, we developed an integrated framework combining the hydrological model, variable infiltration capacity (VIC) model, and geospatial tools to identify potential sites for run-of-river small hydropower (RoR-SHP) plants. The study utilized long-term (1951-2020) daily streamflow data, simulated with the VIC model for design discharge computation at 30%, 75%, and 90% flow dependability. The analysis revealed considerable potential for RoR-SHP development within the GRB, identifying 226 initial sites based on the head along the river, with a combined power and annual energy generation estimate of 92 MW and 0.4 TWh/yr, respectively, at 90% flow dependability. After meticulous screening, 11 potential sites based on the head and the power potential were identified. The detailed analysis during El Niño years demonstrated a decline of approximately 46%, 38%, and 18% in total annual energy at 30%, 75%, and 90% flow dependability, respectively, compared to normal years. Consequently, we proposed nine potential sites based on the head, power potential, and viability under El Niño for RoR-SHP development, capable of maintaining the firm power even during El Niño years. Our findings highlighted the increased risk of power shortages in the GRB during El Niño years, emphasizing the imperative need for implementing water-energy nexus strategies to cope with the risks associated with El Niño events.