The State of the French Mediterranean Coastal Aquifers

ABSTRACT The French Mediterranean coastal aquifers are essentially alluvial, deep sedimentary and karst. Whereas the alluvial aquifers are particularly sensitive to salt-water intru sion, contamination of the deep aquifers is generally due to vertical hydraulic connec tion with the shallow aquifers. As for the karst systems, which are quite well developed f rom Languedoc-Roussillon to Provence-Alpes-Côte d'Azur, their hydraulic pattern is generally complex; consequently the salt-water wedge is difficult to determine and can v a ry rapidly in both time and space. Although aquifer salinisation may be natural, i.e. in surface and karst aquifers (e.g. La Vise, Port Miou), it can also be due to human o v e rexploitation. Fortunately no large areas of French Mediterranean coastal aquifer a re so far concerned by salt-water intrusion. Wa t e r-management tools have been deve loped, as re q u i red by the Water Bill, in close cooperation with the water users and authorities. THE STATE OF THE FRENCH MEDITERRANEAN COASTAL AQUIFERS