Evaluation of intrinsic vulnerability against seawater intrusion using the GALDIT approach. Application to the R’mel aquifer (North West of Morocco)

The map of groundwater vulnerability against pollution is a fundamental document for territory planning. This document allows decision makers to better manage and analyze the information needed to identify areas below which groundwater is vulnerable to pollution. In this context, and considering the strategic role of the R mel aquifer in agricultural development and drinking water supply of Larache region, a groundwater vulnerability map to seawater intrusion using the GALDIT approach was applied. It is a parametric approach based on the combination of six layers of information relating to: Groundwater occurrence, Aquifer hydraulic conductivity, Depth to groundwater Level above the sea, Distance from the shore, Impact of existing status of sea water intrusion in the area and Thickness of the aquifer. The Computed GALDIT index shows two classes of vulnerability fluctuating between the Low and Moderate.