Delineation of groundwater potential zones in lower Rihand River Basin, India using geospatial techniques and AHP

Abstract

In the present study, an attempt is made to delineate groundwater potential zones in Lower Rihand River Basin using remote sensing, GIS, and Analytical Hierarchical Process (AHP). Multiple data, viz. lithology, lineament density, geomorphology, slope, soil, rainfall, drainage density, relief, landuse/landcover were considered for delineating the groundwater potential zones. All nine thematic layers were prepared using remote sensing data on GIS platform. After that, weights were assigned to different layers and the features within them using a pairwise comparison matrix through the Analytical Hierarchical Process. The weights obtained were tested for their consistency using the consistency index and consistency ratio. A final weighted map was then obtained by multiplying each thematic layer’s weights with the weights of features within them and adding them. Based on this final weighted layer, the basin was categorized into very poor, poor, moderate, good, very good groundwater potential zones. The maximum area (49.22%) is under poor groundwater potential zone followed by moderate zone (26.17%), very poor (12.53%), good (11.77%), very good (0.31%). Results obtained have been validated using pre-monsoon and post-monsoon 10 years average water depth and seasonal fluctuation of various observation wells. Sensitivity analysis using map removal method is performed to assess the most influential parameters, geology, geomorphology, lineament density are the most influential. Overall results prove the efficacy of the use of geospatial technology in combination with AHP in the delineation of underground water potential zones.