Application of integrated AHP-entropy model in suitable site selection for rainwater harvesting structures: a case study of upper Kangsabati basin, India

Water is a sustainable asset which, upon supervision, can become a treasured resource for all living beings. The principal objective is to locate potential zones for rainwater harvesting (RWH) with the help of integrated analytical hierarchy process (AHP) entropy model weight and geospatial techniques in a drought-prone watershed as a case study. Here, various thematic maps like runoff coefficient, slope in percentage, drainage density, soil depth, density, geology, proximity to roads, and proximity to urban centers have been utilized in the environment of remote sensing (RS) and geographical information system (GIS). The result shows that the RWH potential zones are qualitatively classified into five suitability classes, such as (i) excellent (44.6%), (ii) good (26.9%), (iii) moderate (19.2%), and (iv) poor (9.3%). Specific sites for check dams, percolation tanks, and farm ponds are also located. Fifteen sites for check dams, 10 sites for percolation tanks, and 12 sites for farm ponds are proposed for construction. In this study, the locations of the potential structures were also compared with the locations of existing structures with the help of Google Earth and catchment visits. Water scarcity due to hydrological and environmental factors in the area hampers the agricultural productivity, due to which poverty in the region is prevalent and people often migrate to other regions for a living. This study gives a cost-effective, accurate, and easy framework for planners and decision makers to locate potential RWH sites for building water and soil conservation structures in different catchments.