Using geographic information methodology to identify aquifer recharge

In arid and semi-arid regions, groundwater is a critical alternative to scarce surface water, essential for sustaining agricultural and industrial activities. The Al-Ghadaf Valley in the Western Desert of Iraq faces severe freshwater scarcity due to climate change and rising demand. However, the region lacks comprehensive hydrological data, making the identification of sustainable water sources a significant challenge for decision-makers. This study aims to delineate Groundwater Potential Zones (GWPZs) to provide a spatial framework for sustainable water resource management and aquifer recharge. An integrated approach combining Geographic Information Systems (GIS), Remote Sensing (RS), and the Analytic Hierarchy Process (AHP) was utilized. Eight thematic layers geomorphology, geology, slope, lineament density, soil infiltration, rainfall, land use/land cover, and drainage density were prepared using Landsat 8 imagery and SRTM DEM data. Geomorphology and geology were determined to be the most influential factors, assigned weights of 24% and 20%, respectively. The basin was classified into five potential zones. The analysis reveals that “Good” and “Very Good” potential zones cover 54.68% of the study area (approximately 4,693 km²), located primarily in the central and western regions. The model was validated using yield data from 28 boreholes, achieving a prediction accuracy of 78.57% and a correlation coefficient (R2) of 0.67. Significantly, field data confirmed that boreholes in high-potential zones produced an average yield of 10.7 L per minute (lpm), compared to only 1.2 lpm in poor-potential zones. The integration of geospatial technology with AHP proved highly effective for mapping groundwater in data-scarce environments. These findings establish a foundational database for local authorities to optimize future drilling locations and implement effective conservation strategies in the Western Desert.