The study compared water balance components in river basins of Eastern India to understand water availability for delta regions. They used a hydrological model to analyze surface runoff, stream flow, and evapotranspiration in different river basins. Results showed that the runoff coefficient was higher in the Hooghly river basin compared to others. Evapotranspiration was lower in the Hooghly basin with less variation over time. The models also revealed how the basins responded differently to low and high rainfall years, affecting the fractions of evapotranspiration and surface runoff. This research helps predict future water availability, demand, and potential impacts on river deltas from events like droughts and floods.