"Reservoir Dynamics: Assessing Sustainable Operations' Impact on Water Cycle"

River impoundments play a substantial role in altering the global water cycle and terrestrial water storage (TWS) dynamics. In light of the vulnerability of the global water cycle to both climate change and human activities, there is a pressing need for an integrated approach to water management that combines scientific insights with sustainable reservoir operation strategies. In this context, the integration of the advanced computational model Noah-MP and an innovative satellite-based reservoir operation scheme called HyMAP offers a comprehensive understanding of the reservoir dynamics of Tawa reservoir situated along the Narmada River in India. To accurately depict absolute water storage, a ground-based lake bathymetry is incorporated into the analysis, merging it with global satellite-based topography. Additionally, radar altimetry data is integrated into the hydrodynamic model to serve as a proxy for reservoir operation practices. Comparing the results against an idealized naturalized system (assuming no anthropogenic impacts) during the period from 2005 to 2022, the study reveals that reservoir operation has a substantial impact on water elevation, extent, storage, and outflow. These operational practices exert control over lake dynamics and TWS, emphasizing the need for a sustainable and informed approach to reservoir management.