Erosion Risk Assessment for Prioritization of Conservation Measures in the Watershed of Genale Dawa-3 Hydropower Dam, Ethiopia

Sedimentation is a leading global problem that affects the environment and dams by reducing live storage capacity of reservoirs life expectance dams. Hence, prioritizing watersheds according to risk soil loss crucial for extending useful reservoirs. The objectives this study were assess sediment flow in Genale Dawa-3 reservoir, identify subbasins are prone erosion, evaluate impact different management practices on minimizing yields using Soil Water Assessment Tool (SWAT) model. SWAT model was calibrated validated observed streamflow data based SUFI-2 algorithm SWAT-CUP, its performance assessed. simulated average annual yield; input reservoir 16.83 ton/ha/yr period 1990–2015. From total 31 subbasins, 12 categorized from high very severe (11–60 ton/ha/yr) sediment-yielding selected management. scenarios showed reductions at critical erosion hot spots after application filter strips, soil/stone bund, terracing, contour farming 35.03%, 66.54%, 80.88%, 53.11%, respectively. Therefore, concluded yield implementing terracing areas more effective than other conservation measures. Overall, research can help planners decision-makers implement appropriate measures most erosive subwatersheds order extend hydropower dam reservoir.