GIS-based morphometric analysis for sub-watershed prioritization of the Seonath River Basin in Rajnandgaon District, Chhattisgarh, India

Abstract This research measures the spatial variability of drainage patterns, assesses hydrological characteristics, and pinpoints sub-watersheds for focused watershed management through GIS-based morphometric analysis of the Seonath River Basin in Rajnandgaon District, Chhattisgarh, India. A 30 m Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) was utilized to calculate morphometric parameters such as drainage density, bifurcation ratio, circularity ratio, elongation ratio, and dissection index. Previous morphometric studies in central India primarily depended on DEM-derived drainage, resulting in uncertainties regarding stream alignment and watershed boundaries. To address this constraint, the research combines SRTM DEM Landsat-8 OLI/TIRS images, to create a precise drainage network and define three sub-watersheds. A new element is the connection of morphometric indices with lithology and slope to analyze runoff behavior, erosion processes, and groundwater recharge capability. The findings show notable variability among sub-watersheds. Sub-Watershed 1 displays increased runoff concentration and flood risk, whereas Sub-Watershed 3 demonstrates heightened erosion susceptibility. The basin's drainage density of approximately 1.43 km km −2 indicates spatial differences in infiltration and runoff, assisting in prioritized and sustainable watershed management.