Combination of Fuzzy and Boolean logic and MCDM Methods for Investigating Suitable Areas for Artificial Groundwater Recharge (Case Study: Chenaran Watershed in Razavi Khorasan Province)

Abstract

More than two-thirds of Iran have been located in arid and semi-arid regions. Overuse of groundwater water resources has decreased the groundwater level in these areas. Artificial recharge plays a pivotal role in the sustainable management of groundwater resources. Investigating suitable areas for optimal use of water floods is one of the most important factors in recharging underground water tables in dry lands where the agricultural and rangelands are vulnerable. Hence, this study proposes a methodology to delineate artificial recharge zones and identify favorable artificial recharge sites using integrated Fuzzy logic, Boolean logic and multi-criteria decision-making (MCDM) methods for augmenting groundwater resources in Chenaran Watershed facing water shortage problems. The thematic layers considered in this study are infiltration rate, slope, geology, geomorphology, land cover, distance to river, distance to road and distance to Qanats and wells, which were prepared using satellite imagery and conventional data. Then, by applying the limiting layer as a combination of four criteria of lithology, land use, slope and geomorphology, the final map of recharge suitable areas was prepared and prioritized from highly suitable to unsuitable. The final obtained map divided the study area into five zones according to their suitability for artificial groundwater recharge. The results were then examined against the existing water spreading site to estimate their accuracy. The artificial recharge suitable zone of the final map was found to be in agreement with the map of water spreading project performed by the Ministry of Agriculture Djehad (accuracy was more than 78%). The results of this study could be used to formulate an efficient groundwater management plan for the study area and other similar areas.