Seawater intrusion modeling under climate and anthropogenic changes in the Metaponto coastal aquifer (Basilicata, Southern Italy)

Abstract

The Metaponto coastal plain, located in the Basilicata region (southern Italy), is a relevant area for economic development due to the touristic and intensive agricultural sectors. In the 20th century, the land reclamation works, irrigation systems, and wells exploitation to support agriculture and industry strongly impacted the hydrogeological system, intensifying the potential seawater intrusion (SWI) that must be considered relevant in this coastal aquifer. The effective infiltration rate of the area is moderate due to the Mediterranean climate conditions, characterized by high temperatures and scarce precipitation concentrated mainly in winter. The present study aims to evaluate and model the SWI process in the most prone area of the Metaponto coastal plain. Groundwater flow and variabledensity transport, under steady-state and transient conditions, were simulated with MODFLOW and SEAWAT codes integrated into Visual MODFLOW Flex 7.0 software. The pumping rate effects and the impact of climate change on the aquifer recharge were considered in different scenario simulations. The results highlighted that the SWI is potentially not negligible in the future under exploitation and may impact the groundwater SWI level risk. The numerical modeling outcomes presented in this work can be used for the effective management of the Metaponto coastal plain groundwater resources.