Advanced Hydro-Geospatial Modeling for Groundwater Potential Zoning in the Baro River Watershed: Geographic Information System and Remote Sensing Approach

Groundwater is vital for ecosystems and livelihoods in sub-Saharan Africa, particularly in Ethiopia, dubbed the “water tower of Africa.” Despite its significance, many areas face water scarcity due to data scarcity and an uneven distribution of resources. The Baro River watershed, covering over 23,000 km2 in Southwestern Ethiopia, poses a critical study area that has been largely overlooked. A hydro-geospatial modeling framework, utilizing remote sensing (RS), Geographic Information Systems (GIS), and Multi-Criteria Decision Analysis (MCDA) via the Analytical Hierarchy Process (AHP), was employed to map Groundwater Potential Zones (GWPZ) across the region. Nine environmental parameters were assessed for their impact on groundwater recharge, with rainfall as the primary influencer. The analysis involved reclassifying and weighting each factor, yielding a Consistency Ratio (CR) of 0.067, well below the acceptable threshold of <0.10, indicating reliable results. The resulting groundwater potential map classified zones into five categories: very high, high, moderate, low, and very low potential. High-potential zones are predominantly located in the Gambella lowlands, benefiting from favorable groundwater infiltration conditions in fractured volcanic and alluvial deposits. In contrast, low-potential areas correspond to steep slopes with dense drainage. The findings reveal significant groundwater development opportunities, with over 90% of the watershed exhibiting moderate to very high potential, suggesting effective water management strategies through the integration of GIS and AHP for enhanced groundwater evaluation.