Abstract: In order to ensure drinking water supply to the inhabitants of Jahjouka village located in the central north of Morocco, a geophysical Geo-electric study has been performed in order to evaluate the water potential of the land in question. The area being studied has from the top up to 20m depth a clay-marl formation containing large blocks of sandstone rocks. This very permeable formation cannot be linked to the characteristic clay formation of the geological unity of Tangier. The main reservoir has a capacity of approximately 50m before turning to true clay of external Tangier. It is at this horizon where the water has been located, trapped and stored.