Remote Sensing and GIS for Sustainable Aquifer Recharge Management in the Cuddalore Coastal Zone, Tamil Nadu, India

This study identifies optimal sites for managed aquifer recharge (MAR) to mitigate groundwater depletion and seawater intrusion in coastal aquifers of Cuddalore district, Tamil Nadu. Using geospatial techniques, it integrates lithology, soil, geology, geomorphology, LULC and aquifer characteristics with GIS-based multi-criteria decision analysis. The Analytical Hierarchy Process (AHP) ranks influencing factors to delineate groundwater potential zones. Approximately 468 km² is classified as having high recharge potential, recommending recharge shafts, percolation ponds and injection wells to enhance groundwater levels by 3-5 meters annually and mitigate seawater intrusion. Validation with 20 years of hydrological data supports the suitability of these zones, emphasizing their role in sustainable water management. The study addresses increasing groundwater stress due to rapid urbanization and climate variability, promoting the use of non-traditional water sources and strategically planned MAR structures. The findings highlight MAR’s potential to replenish aquifers, to improve water quality and to meet the water demands of coastal regions.