Delineation of groundwater potential zones using geospatial techniques and analytical hierarchy process in Dumka district, Jharkhand, India

Abstract

This study aims to delineate groundwater potential zones using an integrated approach of remote sensing, geographical information system (GIS) and Analytical Hierarchy Process (AHP) method in Dumka district, Jharkhand, India. Multiple data as lithology, lineament density, geomorphology, slope, soil, rainfall, drainage density and land use/land cover were considered for delineating the groundwater potential zones. Spatially distributed maps/thematic layers of all the aforementioned parameters were created using remotely sensed as well as ground data in a GIS environment. These thematic layers were assigned suitable weights on the Saaty’s scale according to their relative importance in groundwater occurrence in the study area. The assigned weights of the thematic layers and their features were then normalized by using the AHP technique. Ultimately, all thematic layers were integrated by a weighted linear combination method in a GIS environment to produce a groundwater potential zones map. The delineated groundwater potential zones in the study area, were categorized as ‘very good’, ‘good’, ‘moderate’, and ‘poor’ respectively. The results showed that area along the Mayurakshi River (Rajmahal, Pipra, Lathipahar, Phitkoria, Jhajhapur, etc.) which is approximately 11% (404.96 km2) of the total study area was delineated as an area having ‘very good’ potential for groundwater. The ‘good zone’ delineated encompassed approximately 38% (1,389.61 km2) of the study area and was found in the pediment-pediplain complex zone. The ‘moderate zones encompassed approximately 44% (1,602.07 km2) of the area. The ‘poor zones’ encompassed approximately 7% (260.58 km2) of the area which included Raneshwar, Asanbani, Chichro, Sarni and certain parts of Musna. The groundwater potential zone map was compared with the actual discharge data from various wells within the study area and was found reasonable. Overall, this study provides a convenient approach of delineating the potential of groundwater availability which ultimately will aid in better planning and managing of groundwater resources.