Mapping of groundwater potential zones in Pohru Watershed of Jhelum Basin-Western Himalaya, India using integrated approach of remote sensing, GIS and AHP

There has been excessive use of groundwater resources owing to dwindling water resource potentialities across the globe. As a result, efficient water resource management has become inevitable. However, locating the groundwater potential zones in dry and mountainous regions of many developing countries which lack suitable economic and human resources is challenging. The integrated approach of Remote Sensing (RS) and Geographic Information System (GIS) can offer a solution to this problem as it is useful to fetch first-hand information and has wider applicability. The present study focuses on delineating of groundwater potential zones in Pohru Watershed, of Jhelum Basin-Western Himalaya, India by integrating RS, GIS and Analytical Hierarchy Process (AHP). Seven thematic layers, namely lithology, geomorphology, soil, land use/land cover, slope, drainage density and lineament density have been used in this study. The parameters were weighted using AHP according to their importance in determining the groundwater potential. Five major groundwater potential zones were identified as: Very High (18.14%), High (18.17%), Moderate (19.03%), Low (41.75%) and Very Low (2.88%). The findings reveal that High and Very High Potential Zones are concentrated in the alluvial plains and the adjoining fluvio-lacustrine deposits/ Karewas. However, the highly or moderately dissected hills and the mountain ridges mostly comprise of Low and Very Low groundwater potential zones. The residual hills comprise of Medium and Low groundwater potential zones. The analysis of location and water depth of groundwater wells in the study area was found in accordance with the mapped groundwater potential zones, which validates our study. The Area Under Curve (AUC) value of Receiver Operating Characteristic (ROC) curve for AHP method was calculated as 0.7037, which corresponds to the prediction accuracy of 70.37%, indicating Moderate to High predictability of groundwater recharge zones for the study region.