Comparison of Three Groundwater Vulnerability Assessment Methods in Minab Aquifer, Iran

Groundwater protection is a major challenge in arid and semi-arid region because it is the main source of water in these areas. In addition to water quantity, the water quality is getting worth due to wastewater discharges, increasing salinity and overdraft usage. Therefore, it is necessary to use a proper method to prevent these resources from being polluted. Groundwater vulnerability is one of these methods which can help decision makers to assess aquifer potential to pollution before it happens. In this paper, three widely used vulnerability assessment methods, DRASTIC, SINTACS, and GODS, were compared in an arid region in Iran. The results of this study showed that DRASTIC and SINTACS are close in classification and most of the aquifer is grouped in moderately and highly vulnerable but in GODS very low and low had the highest coverage. Considering the high water table in the region and coarse soil material which causes high hydraulic conductivity and infiltration, it is reasonable to accept the results of DRASTIC and SINTACS. At the end, it was concluded that DRASTIC is an acceptable method to evaluate the groundwater vulnerability in Minab aquifer due to using the effective parameters and reasonable results.