This study aims to optimize Managed Aquifer Recharge (MAR) in coastal aquifers through an integrated circular economy-based framework combining FEFLOW groundwater modeling, GIS analysis, and Multi-Criteria Analysis (MCA). The methodology was applied to the Nabeul-Hammamet coastal aquifer (Tunisia), a semi-arid system affected by overexploitation and seawater intrusion. The approach integrates hydrogeological modeling with spatial decision-support tools to identify optimal recharge locations and evaluate recharge performance under different operational scenarios. Results show that moderate-permeability zones (10(-)(6) - 5 & times; 10(-)(5) m/s) provide the best balance between infiltration and groundwater retention, achieving piezometric recovery of up to + 35 m by 2070 while limiting hydraulic losses toward the coastal boundary. A recharge threshold of 75% of system capacity achieves approximately 80% of maximum recovery while minimizing inefficiencies. The GIS-MCA framework further reduces implementation costs by 30% and land requirements by 22% compared to conventional approaches. These findings demonstrate the potential of MAR as a circular water management solution to enhance groundwater sustainability and mitigate seawater intrusion in semi-arid coastal regions. The proposed framework provides a transferable decision-support tool for groundwater management strategies robust under historical hydroclimatic variability and supports the integration of treated wastewater reuse within sustainable water policies.