Abstract
Water scarcity is the most serious environmental challenge that Jordan faces. Water resources require better protection and management as groundwater accounts for about 50% of the water usage in Wadi Shueib, central Jordan. Intrinsic vulnerability for Wadi Shueib (a valley located south of As-Salt city) watershed was assessed using modified SINTACS model using GIS techniques. According to our model, the investigated area encompassed very high, high and moderate areas of potential pollution with area coverage <1%, 26% and 51%, respectively. The high potential pollution is mainly influenced by combined contributions of parameters such as; unsaturated zone, aquifer media, lineaments density and effective infiltration.
Sensitivity analysis indicates that lineament density is significant for the calculation of the groundwater vulnerability index. Nitrate concentrations measured in selected wells and springs were compared with the model to inspect its reliability. The validation rate of our model reaches more than 70%, which is an indication of acceptable modelling approach. Moreover, there was a good match of vulnerability classes with land use land cover categories as indicators of groundwater vulnerability. The SINTACS method proved its versatility even in this complex hydrogeological environment.