SWAT-BASED HYDROLOGICAL ASSESSMENT OF THE WAINGANGA RIVER CATCHMENT

Abstract

The Wainganga River Basin in Maharashtra, a critical component of the Godavari River system, faces increasing hydrological stress due to urbanization, land use changes, and climate variability. To address these challenges, this study employed the Soil and Water Assessment Tool (SWAT) integrated with GIS to assess surface runoff dynamics and evaluate the watershed’s response under varied physiographic and climatic conditions. The main objective was to simulate hydrological processes—including surface runoff and streamflow—based on inputs from high-resolution land use/land cover (LULC), soil, topographic, and daily hydro-meteorological datasets. The basin was discretized into 2,468 sub-basins and 10,594 Hydrological Response Units (HRUs). The SWAT model was calibrated using observed streamflow data for the period 2015– 2019 and validated for 2020–2024. The model's performance was evaluated using statistical indicators: R² was 0.86 for calibration and 0.89 for validation; RMSE values were 6.32 and 8.32 respectively; and Index of Agreement (IA) values were 0.82 (calibration) and 0.56 (validation). These results confirmed the model’s accuracy in replicating seasonal runoff patterns and peak flow events. The study concludes that the SWATGIS framework is a reliable decision-support tool for watershed management, offering robust predictive capabilities even in data-scarce or topographically complex regions. The findings can inform sustainable water planning, especially in regions undergoing rapid land cover transformation.