GIS-based delineation of groundwater potential zones using AHP: a case study of Shimla district

Groundwater is an important resource for domestic consumption, industrial and agricultural use. Overexploitation of groundwater, unpredictable rainfall and severe climate change have imposed a pressure on global groundwater resources. As demand for potable water is increasing, there is a need for evaluating and mapping groundwater potential. In Shimla district, people are dependent on the groundwater for household/agriculture purpose. Geospatial-based studies have gained importance in mapping of groundwater potential zones. This study has been undertaken to create the groundwater potential zone map of Shimla district. The analytical hierarchy process (AHP) was employed to delineate groundwater potential zones. Seven thematic layers were analysed using ArcGIS. Pairwise comparison matrix is formed for these layers and are analysed using weighted overlay analysis tool in ArcGIS. The results are presented as a groundwater potential map with five classes: very low, low, moderate, high and very high. Validation was performed using water yield data through the area under curve method. The AHP is widely recognised as an effective method for groundwater potential mapping and monitoring. The results show that 39% of the district area falls under high groundwater potential, while 47% has moderate potential. These findings can support effective groundwater planning and policy formulation.