Integrated GIS-Based Multi-Criteria Analysis for Groundwater Potential Mapping in the Euphrates’s Sub-Basin, Harran Basin, Turkey

Abstract

The Harran Basin is an important region where agricultural activities have been conducted for millennia. The agricultural water needs of the basin are largely met with surface irrigation through the GAP (South-Eastern Anatolian Project), while groundwater is used in some regions as potable water, tap water, and irrigation water. In this study, the groundwater potential of the Harran Basin was determined through the “GIS-based Multi-Criteria Decision Making (MCDM)” Method. Ten criteria were considered: Land Use, Soil, Geomorphology, Geology, Aquifer, Drainage Density, Rainfall, Slope, Lineament Density, and Terrain Class. The weights of these criteria were determined through the AHP method, and the operations were performed in the ArcGIS environment. As the results of this study, the Groundwater Potential Index (GWPI) values were obtained, and five regions were determined based on their Groundwater Potential Zone (GWPZ) classifications: very poor GWPI: 0.10% (5.14 km2); poor GWPI: 29.20%; moderate GWPI: 38.20%; good GWPI: 30.90%; and very good GWPI: 1.50%). We determined that the region is a plain with a low slope and geologically consists of limestone. Notably, areas with poor water potential are mountainous and hilly, and the slopes over these areas are high.