Assessment of groundwater vulnerability to pollution as part of integrated management in coastal areas Case of Ghiss-Nekkour Basin (North East of Morocco)

Many methods for assessing the vulnerability of groundwater against anthropogenic pollution have been developed in the past decades. However, if aquifer vulnerability concept is well defined and the methods have been constantly tested and compared, the problem of the choice of the best method remains. The choice of the method depends on a series of factors, including the scale of the problem, the hydrogeological characteristics of the area and data availability. From a pile of a vulnerability assessing methods, the GOD, DRASTIC and SI approaches have been the most extensively tested. This is why, in the present work, we applied them to evaluate the groundwater vulnerability of the Ghiss-Nekkour aquifer, located in North East of Morocco, on its Mediterranean shore. The mapping resulting from the application of the three approaches shows a range of intervals divided into classes corresponding to fluctuating degrees of vulnerability from “very low” to “extreme”. The coincidence rate between the nitrate distribution of the groundwater and the mapped vulnerability classes is higher when the SI approach is applied. Such mapping constitutes basic documents guiding the land planner in decision-making within a framework of territorial intelligence and integrated management of the Ghiss-Nekkour coastal basin.