Determining and Prioritizing of flood spreading suitable sites for qanats, wells and springs recharging in arid regions

Flood spreading will be more important and critical if drought occurred in arid and semi arid regions. Object is determination and prioritizing of flood spreading suitable sites for qanats, wells, and springs recharging in arid regions by using spatial multi criteria methods and GIS to combat with aridity and drought critic. Miankouh watershed in south of Yazd with 618 Km2 was selected as study area. In this study spatial economical factors such as proximity to road, qanat, well and spring were considered. Spatial natural factors and constraints such as vegetation cover density, geomorphology, land use and slope were interposed in the tree model. In spatial multi criteria evaluation method, factors were standardized through Boolean and fuzzy logics. Factor weights determined with ranking method. In next step with tree model and visual programming layers were combined in GIS environment that its result was composite index map (CIM) with fuzzy values. As a result, suitable region for flood spreading with values near to one were consisted areas with 15.02 km2 and all three priorities 2.43% of whole area in the watershed. This district had suitable common cover with region implemented flood spreading project. So, this method is recommended for determining suitable flood spreading sites in the same watershed areas.