Mapping Groundwater Potential Using Geospatial Techniques and AHP-Based Multi-Criteria Decision Analysis

Groundwater is a vital water resource in Ethiopia, particularly in areas where surface water is limited and highly seasonal. This study delineates groundwater potential zones in the Azuari watershed, upper Blue Nile basin, Ethiopia, using an integrated Remote Sensing (RS), Geographic Information System (GIS), and multicriteria decision making-Analytic Hierarchy Process (AHP) approach. Six key thematic factors such as lithology, slope, soil types, drainage density, lineament density, and land use/land cover were derived from satellite imagery, digital elevation models, and geological and soil datasets. relative weights were assign using AHP, and consistency ratios confirmed acceptable judgment reliability. The weighted overlay technique was then applied to generate the groundwater potential map. The watershed was classified into five groundwater potential zones such as very high, high, moderate, low, and very low. Moderate to very high potential zones account for 68.3% of the area, indicating generally suitable groundwater conditions. High potential zones are mainly associated with fractured and weathered lithologies, high lineament density, gentle slope, low drainage density, permeable soils, and forest or agricultural land use, whereas low-potential zones correspond to steep slopes, dense drainage networks, low lineament density, massive lithology and impervious surfaces. Validation using 61 borehole records indicates strong agreement, with 88.5% of boreholes occurring within moderate to very high potential areas. The results confirm that the RS-GIS-AHP approach is a reliable and cost- effective tool for groundwater assessment in data-scarce regions. The generated map provides valuable support for groundwater exploration, borehole site selection, and sustainable water resource management in the Azuari watershed.