Unlocking the hidden depth: mapping groundwater potential in Melka Soda district, Genale–Dawa Basin, Ethiopia

Abstract

Groundwater is a crucial resource due to its consistent availability and good natural quality. Water resources in the Melka Soda district face significant challenges due to poor rainfall and a lack of surface water. To investigate groundwater potential zones in the Melka Soda district, the present research integrates remote sensing (RS), geographic information system (GIS), and analytical hierarchy process (AHP) methodologies. Based on the literature and expert opinions, eight controlling factors were chosen: rainfall, geomorphology, land cover, soil texture, lineament density, lithology, drainage density, slope, and land use. Appropriate weights were assigned to each component in the AHP in accordance with their relative significance in the area’s groundwater occurrence. Weighted sum overlay analysis was utilized to aggregate all factors, and the resulting groundwater potential index was applied to detect four groundwater potential zones, viz., very low 245.3 km² (14.5%), low 535.9 km² (31.7%), moderate 558.1 km² (33%), and high 347.3 km² (20.8%). This implies that more than half, 905.4 km² (53.8%) of the study area is categorized as having moderate to high groundwater potential. These identified groundwater potential zones were overlaid with discharge data from 21 wells and boreholes and showed an accuracy of 85.7%. The findings can be used to plan and execute more efficient water management strategies and future development projects.