Unveiling groundwater gems: A GIS-powered fusion of AHP and TOPSIS for mapping groundwater potential zones

Groundwater is indispensable to various sectors like industry, households, and agriculture, yet its assessment remains critical. This research focuses on evaluating potential groundwater zones within the Jamsholaghat watershed, employing a robust geospatial approach. Twelve thematic maps, spanning factors influencing groundwater recharge, namely lithology, drainage density, distance from river, land use and land cover, lineament density, rainfall, hydrological soil group, roughness, geomorphology, topographic position index, slope, and topographic wetness index underwent a multicollinearity check for independence before integration using ArcGIS's weighted overlay analysis. Utilizing a combination of the Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) and the Analytical Hierarchy Process (AHP), each thematic map was ranked based on its relative significance in groundwater recharge. The resulting Groundwater Potential Zone (GPZ) map divided the region into high (40%), medium (52%), and low (8%) potential zones. Notably, the easternmost part emerged as the most conducive for recharge, attributed to factors like favorable lithology (laterite and quartz), geomorphological features (water bodies and flood plains), high rainfall, and gentle slope. This insight can inform targeted interventions for sustainable groundwater management. This practical information empowers water resource managers to prioritize exploration efforts. By focusing drilling activities on high-potential zones, success rates can increase, saving time, money, and minimizing environmental impact. Furthermore, understanding recharge-influencing factors can guide land-use practices that promote infiltration, ensuring the long-term sustainability of this vital resource. This research paves the way for informed decision-making, fostering sustainable groundwater management practices within the Jamsholaghat watershed.