Evaluation of groundwater potential by GIS-based multicriteria decision making as a spatial prediction tool: Case study in the Tigris River Batman-Hasankeyf Sub-Basin, Turkey

The Tigris River Batman-Hasankeyf region sub-basin drainage area is in the Upper Tigris basin and lies between the area where the Batman stream joins the river and the Yanarsu stream flows into the river. Intensive agricultural activities are carried out in this region, and irrigation is generally obtained from groundwater just as it moves away from the riverfront. The study area is a valuable basin for both Turkey and the Middle East. In this study, the effectiveness of the Geographic Information System (GIS)-based multicriteria decision-making (MCDM) analytic hierarchy process (AHP) as a spatial prediction tool was utilized in exploring the groundwater potential of the drainage area. In the analysis, eight hydrological and hydrogeological criteria were considered as influencing factors, namely, geomorphology, geology, rainfall, drainage density, slope, lineament density, land use, and soil properties. The weights of these criteria were determined through the AHP method; the Arc GIS 10.2.2 program and its submodules were used. The major findings of the study were that groundwater-potential index values of the basin were derived. Groundwater-potential-zone evaluation of the basin was obtained as follows: very poor (19%), poor (17%), moderate (34%), good (17%), very good (13%); and groundwater potential zone (GWPZ) maps of the sub-basin were created.