The core objective of this research is to assess groundwater quality and potential in the upper Omo-Ghibe basin of the Walga catchment using hydro chemistry, recharge estimation, and aquifer characterization using Aquifer test. Rainfall, wind speed, temperature, relative humidity, and sunshine hours were recorded from meteorological stations in the catchment and the surrounding area. In the Walga catchment, water balance, CMB and WTF was used to calculate long-term seasonal/annual average spatial and temporal groundwater recharge, real evapotranspiration, and surface runoff as a function of land-cover, soil type, topography, and hydro-meteorological factors. Surface runoff accounts for 38.75 percent of total annual precipitation, evapotranspiration accounts for 54.22 percent of total annual rainfall, and the Walga catchment's groundwater is recharged with 120mm/yr of rainfall. The catchment's mean annual recharge was found to be 7.5 percent of precipitation using the model, while surface runoff was 38.25 percent of annual precipitation. The hydraulic properties of the aquifer were calculated from the pumping test by using computer software called AQUIFER TEST to match mathematical models (type curves) to response data (water table changes). Transmissivity ranges from 3.5 x10-4 m2/day to 290 m2/day, with an average of 50.94m2/day. Yield or discharge of bore holes values vary from 0.15 l/sec to 61 l/sec, while yield or discharge of bore holes values range from 0.15 l/sec to 61 l/sec. The hydraulic conductivity fluctuates from 0 to 16.04 m/se, with a mean of 1.2 m/se. The average yield from 72 boreholes is 430 liters per second (119.4 m3/hr), or 37152000 liters per day. Because of the impact of impermeable soils, morphology of the land, and land use land cover of the city, the study area has the lowest groundwater recharge compared to surface runoff and real evapotranspiration. To account for varying geology, the highest scale values were given to fractured mokonnin basalt and lower jimma basalt, while the lowest scale values were given to wochecha trachyte and wonchi dendi pyroclastic fall contribution in assessing groundwater potential. With the main north east to south west flow directions. In general, the area has been evaluated using safe standards for all hydro geochemical and hydrogeological parameters