Study region: The Konya Closed Basin, a 50,000 km2 semi-arid agricultural region in central T & uuml;rkiye, with severe groundwater depletion due to intensive irrigation and uncontrolled well drilling. Study focus: We developed and applied a coupled socio-hydrological model that integrates a process-based groundwater flow model (MODFLOW-UZF) with a system dynamics model (VENSIM) to simulate both hydrogeological processes and human decision-making. A Python-based coupling framework enables the bidirectional exchange of variables across different spatial and temporal resolutions. The coupled model, calibrated using historical groundwater level data from long-term observation wells, is used to test the impacts of various policy configurations, including crop pricing, extraction caps and surface water transfers. New hydrological insights for the region: The coupled model captures both seasonal variability and long-term depletion trends more accurately than stand-alone models. We demonstrate that spatial and temporal disaggregation of policy measures can significantly enhance groundwater resource management. By incorporating feedback between aquifer conditions and farmer decisions, the model demonstrates how socio-economic and hydrological drivers jointly shape groundwater dynamics. Through this coupling, we emphasize the advantages of harnessing the respective strengths of each modeling approach to overcome the limitations of the other. These insights highlight the value of integrated modeling for sustainable groundwater governance in datascarce, densely-irrigated regions.