Geospatial and multi-criteria decision approach of groundwater potential zone identification in Cuma sub-basin, Southern Ethiopia

Groundwater is an essential component of our country's freshwater supplies. It plays a critical role in satisfying the water demands of the nation's many user sectors. The groundwater resource cannot be exploited and sustained optimally unless prospective zones are identified prior to the drilling of wells. The current study intended to analyze groundwater potential possibilities in the Cuma sub-basin, Omo Gibe basin, southern Ethiopia, utilizing geospatial and multi-criteria decision analysis approaches. For this purpose, a range of thematic layers like geology, Rainfall, drainage density, slope, land use and land cover (LULC), Soil type, faults density, saturated hydraulic conductivity, Available water capacity, and soil depth were organized for the study area. The different sub-criteria of each theme layer were rated according to their effect on groundwater recharge, and a weight-age was assigned to each thematic layer based on the analytical hierarchy method (AHP). The identification of groundwater-potential regions of the sub-basin was one of the study's main results. The resulting groundwater potential zone map is further classified into five groundwater potential classes: very good (7.01%), good (19.49%), moderate (17.48%), poor (29.51%), and very poor (26.51%). The study's findings have important significance for developing sustainable groundwater strategies in the area.