Watershed prioritization using multi-criteria decision analysis tool for Bhopal (upper) lake catchment, Madhya Pradesh

Abstract

Watershed prioritization involves the identification of critical areas that are vulnerable to soil erosion and produce higher sediment yield. These areas need conservation activities on a priority basis. The soil erosion and subsequent yield from different watershed areas depend on multiple factors, so the selection of watershed based on a single factor may have the potential risk of wrong selection. The multi-criteria decision support-based analytical hierarchical process can be used conveniently for prioritization of watershed, where erosion process relies on various interdependent and spatially distributed factors. For prioritization, Bhopal Lake catchment was divided into twentyfour sub-watersheds (SW-1 to SW-24) and ten erosion hazard parameters (EHPs) were analysed for all sub-watersheds, which were used as inputs in a decision support system for the identification of erosion-prone areas. Based on susceptibility to erosion and sediment yield, the sub-watersheds were classified into five priority categories: very high, high, medium, low, and very low for the conservation and management of subwatersheds. The sub-watersheds SW-19 and SW-24 have been characterized as a very high erosion area covering about 26 km2 area, which is 7% of the total study area where immediate implementation for soil and water conservation (SWC) measures are required.