Coupled Geophysical and Hydrogeochemical Characterization of a Coastal Aquifer as Tool for a More Efficient Management (Torredembarra, Spain)

The aquifers of the Spanish Mediterranean coast are generally subjected to intense exploitationto meet the growing water supply demands. The result of the exploitation is salinizationdue to the marine saltwater intrusion, causing a deterioration in the quality of the water pumped,limiting its use for community needs, and not always being well delimited. To prevent deterioration,a groundwater control network usually allows precise knowledge of the areas affected by saltwaterintrusion but not the extent of the saline plumes. Moreover, the characterization of aquifer systemsrequires a model that defines the geometry of aquifer formations. For this objective, we integratedhydrogeological, hydrogeochemical, and electrical resistivity subsoil data to establish a hydrogeologicalmodel of the coastal aquifer of Torredembarra (Tarragona, NE Spain). In this research, wehave carried out a regional and local-scale study of the aquifer system to define the areas prone tobeing affected by saline intrusion (electrical resistivity values below 10 Wm). The obtained resultscould be used as a support tool for the assessment of the most favorable areas for groundwaterwithdrawal, as well as enabling the control and protection of the most susceptible areas to be affectedby saltwater intrusion.