Groundwater Potential and Sub-Watershed Prioritization in the Pokoria River Basin, Assam

Abstract

The Pokoria River Basin covering parts of Morigaon and Nagaon districts of Assam, India, spans approximately 1,712 km². Using a river morphometric analysis, this study examines the geomorphological parameters of the basin to rank its sub watersheds for improved groundwater resource planning. SRTM (Shuttle-Radar Topography Mission) DEM data is processed in ArcGIS platform to analyze various morphometric parameters (areal, linear, and relief aspects) along with slope, LULC, and the Dissection Index for delineating groundwater potential zones. After identifying the six sub watersheds within the basin, each watershed was evaluated separately. It was found that sub watershed 4 is a priority location for water and soil conservation measures. The final results show that it has the highest drainage density and stream length, indicating a dominance of surface runoff. On the other hand, sub watershed 2 has comparatively low stream frequency and drainage density, which are better for infiltration and groundwater recharging. The results demonstrate that morphometric analysis offers a dependable and economical method of watershed prioritization when accompanied by remote sensing and GIS. For regions with limited data and a high risk of flooding, where sustainable water management is still a pressing issue, this type of study is quite helpful.