Application of the DKPR Model for the mapping of the vulnerability of surface water to contamination: Case of the 9 April 1947 Dam (Northern Morocco)
In this work we present a method for assessing and mapping the vulnerability for water contamination around the 9 April 1947 dam in Morocco. These waters are subject to high levels of pollution and a significant anthropogenic activity, despite the fact that they are intended to supply drinking water for more than 760 000 people. To do this, we applied the DKPR Model, which includes four factors: accessibility of the aquatic environment (D), hydric functioning of the soil (K), slope (P) and susceptibility to rain erosion (R).The weighted sum of these factors, obtained with GIS software, gave us a vulnerability index named (Vr) and a ranking from 0 to 4. On the basis of this index, a vulnerability map was developed for contamination throughout the watershed. Areas with medium or low vulnerability occupy respectively 43% and 38% of the catchment area. They are mainly linked to the forest and agricultural domains with medium and low slopes. Areas of high vulnerability occupy 14% of the surface area and are linked to high-slope man-made areas. Areas with very low or very high vulnerability occupy only 4% and 1% of the surface of the watershed, respectively. The former correspond to wetlands whereas the latter are the impervious bare lands with steep slopes.