Hydrodynamic analysis of a Mediterranean aquifer system with the use of hydrochemical and isotopical analysis as supporting tools

The management of groundwater resources in coastal environments within the Mediterranean basin has become of paramount importance, especially in the light of global changes. A typical example of such a hydrosystem is the Lavrio basin in Greece. This research site involves two aquifer types—granular and karstic formations—that are hydraulically interconnected. Furthermore, the proximity to the sea and the abstractions for irrigation and drinking water supply have led to the phenomenon of seawater intrusion. The present study aims at analyzing the hydraulic, hydrological, and hydrogeological conditions of the area by means of hydrochemical and isotopical data interpretation as supporting tools, which will inform and support the development of an integrated conceptual hydrogeological model of the area. Field investigations were conducted in order to collect piezometric and chemical data and use them to retrieve the quantitative and qualitative status of the local aquifer units. New interpretation of an older dataset gave an insight into how the karstic aquifer behaves in terms of hydraulics. The results have also demonstrated that there is a hydraulic connection between the different aquifers and the Mediterranean Sea, while natural recharge was quantified for both aquifer types.