Locating Areas Suitable for Groundwater Artificial Recharge with Fuzzy Model (Case Study, Lorestan Province)

Iran is a dry land with very little rainfall. The average rainfall in Iran is less than a third of the global average. Nowadays, with the increase in population and the subsequent increase in demand for food, the utilization of water resources, and in particular groundwater resources, is considerably increased. Currently the amount of groundwater resources exploitation exceeds its supply and so the lack of groundwater resources should be compensated. The purpose of this study was to locate zones suitable for the artificial recharge of the aquifers with a case study for Lorestan Province. For this purpose, AHP was employed as an efficient techniques and comprehensive system designed for multiple criteria decision-making. Required layers such as the slope, soil and geological structure, land use, rainfall, distribution of Quaternary alluvial and satellite imagery of the area was prepared. Then GIS software was used to overlay the layers and information and with use of Fuzzy logic, distinguishing suitable sites for artificial recharge of groundwater and the flood spreading. Based on the results, form the total area of ​​the province (28294 km²), about 9258.36 km² (32.5%) are suitable for the design of artificial recharge and 5926.36 km² (about 21%) can be considered for flood spreading. Finally, the integration of the two resulting maps led to suitable sites for artificial recharge and flood spreading as about 7682.21 km² (21.79%). Therefore, GIS models are a powerful tool to locate artificial recharge and flood plain sites, because of their ability for analysis of large geographical data and prioritization of scientific decisions.