Spatial Delineation of Groundwater Potential Zones Using GIS RemoteSensing and the Analytic Hierarchy Process in Beledweyne, Somalia

Abstract

Beledweyne, Somalia, faces recurring water-supply pressures arising from variable rainfall, flooding, drought, surface-water contamination, and limited treatment infrastructure. This study delineates groundwater potential zones by integrating geographic information systems, remote sensing, and the analytic hierarchy process. Six thematic factors—rainfall, geology, slope, drainage density, lineament density, and soil type—were standardized, weighted through pairwise comparison, and combined in a spatial overlay model. The resulting map classified the study area into very low, low, high, and very high groundwater-potential zones. High- potential areas covered 36.52% of the study area, while very-high-potential areas covered 19.30%; together, these zones accounted for 55.82% of Beledweyne. The most favorable zones were associated with permeable geological conditions, lower drainage density, and greater rainfall contribution. Borehole and dug-well locations obtained from the FAO SWALIM water- source database were overlaid on the potential map as a spatial plausibility check. The findings provide a screening tool for prioritizing hydrogeological investigation, borehole siting, managed recharge, and water-resource planning. The map also identifies lower-potential areas where groundwater development may require greater caution and additional evidence. Because the model relies on weighted thematic layers and does not report a quantitative validation statistic, the mapped classes should guide field investigation rather than replace pumping tests, water-quality assessment, or long-term groundwater monitoring.