Use of GIS to Estimate Recharge and Identification of Potential Groundwater Recharge Zones in the Karstic Aquifers, West of Iran

Abstract

Estimating and studying groundwater recharge is necessary and important for the management of water resources. The main aim of this work is to estimate the value of the annual recharge in some parts of the Kermanshah and Kurdistan province located in the west of Iran. There are many approaches available for estimation of the recharge, but RS (remote sensing) and GIS (geographic information system) have provided and combined a lot of effective spatial and temporal data of large areas within a short time. For this purpose, nine information layers including the slope, aspect of slope, lithology, lineament density, drainage density, precipitation, vegetation density, soil cover, and karst features were prepared and imported to the ArcMap software. After preparing the information layers, they have to weigh based on their effects on the value of the recharge. In order to be weighted the different parameters, methods of judgment expert, reciprocal influences of parameters, and AHP were used. Using GIS, the results obtained from the final map indicated the average value for the recharge based on the average calculated coefficient of recharge. The annual recharge coefficient in the study area was estimated to be between 30% and 80%.