Assessment of the vulnerability of groundwater to the pollution : Case study of the Gourrama aquifer (Eastern of the High Atlas, Morocco)

The Gourramaaquifer is located in the eastern High Atlas of Morocco. The geological formations consist mainly of calcareous-dolomitic and marls of the Jurassic. Limestones play a regulatory role that results in sustained low flow rates that are derived for irrigation. Springs and water withdrawals are the main outputs of the Jurassic aquifer. The total flow of springs catching the Jurassic aquifer is estimated at nearly 790 l/s.The assessment of groundwater vulnerability is a fundamental approach to sustainable environmental management, its role is to enable decision-makers to the better manage the use of underground resources and to analyze the information needed for the protection of thegroundwater against the threat of natural or man-made pollution. In this context, the hydrodynamic characteristics of the Quaternary aquifer and its importance in socio-economic development in the upper Guir Basin lead us to deal with this subject for establishment of two vulnerability maps of this aquifer by the DRASTIC method and the P.R.K methodological approach.These approaches, based on the principle of class system parametric methods, have for main objective to design two index cards related to the intrinsic vulnerability of the Gourramahydrogeological system, by gathering the global indices by the classes of each method