Groundwater Recharge Estimation in Upper Gelana Watershed, South-Western Main Ethiopian Rift Valley

Estimating the spatial and temporal patterns of groundwater recharge through integrated water balance modeling plays an important role in sustainable resource management. Such effort is particularly essential for data-scarce regions, such as Rift Valley Lake basin Basement Complex Ethiopia, which has shallow aquifers, a proliferation wells, poor monitoring networks. A spatially distributed model (WetSpass), along with GIS remote sensing tools, was used estimation its suitability efficiency hydrogeological regions. The WetSpass depicted very good performance simulating Upper Gelana watershed within basin. analysis revealed that about 7% mean annual rainfall converted to recharge, remaining amounts are partitioned into surface runoff (19%) evapotranspiration (75%). simulation outputs also investigate relative influences biophysical driving factors on components. While land use types had greater influence actual processes, soil texture classes were dominant processes watershed. rates found be higher than 400 mm/yr central parts (Fisehagenent, Tore, Gedeb) lower 165 southern (Hageremariam) areal proportions low, medium, high recharging are, respectively, estimated 15%, 68%, 17% area. Therefore, should taken consideration developing resources management plan Managed aquifer can adopted medium capture stormwater during wet season improve supply dry months. Furthermore, monthly withdrawals regulated according