Summary The aquifers of the Spanish Mediterranean coast are generally subjected to intense exploitation to meet the growing water supply demands. The result of the exploitation is the salinization due to the marine saltwater intrusion, causing a deterioration in the quality of the water pumped and limiting its use for certain needs of the community. To prevent the deterioration, a groundwater control network usually allows a precise knowledge of the areas affected by saltwater intrusion, but not the extent of the saline plumes. Moreover, the characterization of aquifer systems requires a model that defines the geometry of aquifer formations. For this objective, we have integrated data of hydrogeological, hydrogeochemical, electrical resistivity subsoil data to establish a hydrogeological model of the coastal aquifer of Torredembarra (Tarragona, NE Spain). In this research, we have carried out a regional scale study of the aquifer system to define the areas prone to be affected by the saline intrusion. The obtaining results could be used as a support tool for the evaluation of the most favourable areas for groundwater withdrawal, as well as assessing vulnerability to contamination of aquifers, enabling the protection and control of the most susceptible areas to be polluted by saltwater intrusion.