Prioritization of Subwatershed Using Remote Sensing and Geographic Information System in Gandaki Province, Nepal

ABSTRACT Watershed degradation is a significant global problem, and as a mountainous nation, Nepal faces even greater challenges in managing its water resources. Because it is largely unrealistic to execute management plans at a time for a large spatial extent, subwatershed prioritization has now become a promising approach for managing watersheds. Our study delineated and prioritize subwatersheds in the Gandaki Province, Nepal, utilizing geospatial technique‐based morphometric analysis for the first time at provincial level. Using Digital Elevation Model having a 30‐m resolution in ArcGIS, we delineated 121 subwatersheds across the province, ranging in size from 29 to 796 km 2 . Subwatersheds were quantitatively ranked for prioritization by assigning a 60% weight to biophysical parameters and 40% to anthropogenic factors. The study's approach is novel in its inclusion of road network density and livestock density within the anthropogenic aspect, each assigned 10 points, alongside population density that received 20 points. Eleven subwatersheds, one from each district, were prioritized because of the highest degradation risk. Myagdi Khola 3 in Myagdi district, covering an area of 309 km 2 , and Kali Gandaki Nadi 1 in Parbat district, covering 33 km 2 , were the two highest prioritized subwatersheds with a prioritization score of 100. The subwatersheds scoring higher priorities should be adopted for development and management programs with immediate effect. This prioritization approach directly contributes to Sustainable Development Goals by promoting targeted action for water resource management, supporting ecosystem preservation, and climate resilience.