Regional scale simulation of integrated surface-groundwater model for a basin along the west coast of India

An integrated hydrological model plays a crucial role in maintaining and ensuring the sustainability of water resources. This study presents a test case for the development of an integrated surface-groundwater model using MODFLOW 6, the latest version of MODFLOW, and FloPy to simulate major hydrological processes and support sustainable water management in a tropical basin where the demand for fresh water is increasing at an alarming rate.

The model incorporates the Unsaturated Zone Flow (UZF), Streamflow Routing (SFR), and Water Mover (MVR) packages to simulate groundwater recharge, surface water dynamics, and interconnections between hydrological components. Input datasets include precipitation, PET, land use, soil, and hydrogeological properties to reflect the basin’s hydrological complexity.

The simulated model was calibrated and validated against observed streamflow and groundwater head data to ensure accuracy and reliability. We showed that the model effectively reflects key hydrological processes, such as monsoon-driven recharge and surface-subsurface interactions. These findings show the model’s ability to guide water resource planning in the basin.

This study illustrates the applicability of MODFLOW 6 and FloPy for hydrological modeling in tropical basins and provides a foundation for assessing climate change impacts on regional water resources.