Located in the Northeast of Tunisia and recognized for several decades as an agricultural region, Cap Bon has experienced population growth, leading to the overexploitation of groundwater resources (mainly the phreatic aquifers), especially by farmers. The uncontrolled use of the phreatic aquifer on the eastern coast of Cap Bon has caused a decline in piezometric levels, accompanied by a reversal of the hydraulic gradient. Seawater infiltrating this aquifer has caused contamination and salinization of the freshwater. The aim of this work is to confirm marine intrusion in a carefully selected study area, to detect the saltwater wedge front, and to determine the evolution and lateral and vertical behavior of the saline waters in the aquifer, using multiple methods (geophysics and geochemistry).