Surface Water Potential Assessment by Using HEC-HMS (Case Study Dabus Sub Basin, Abay/Nile Basin, Ethiopia)

摘要

The surface water resources potential assessment requires detailed insights into hydrological processes. This study mainly focused on the assessment of surface water resources potential in Dabus sub-basin of Ethiopia. HEC-HMS model was used to simulate the flow of the sub-basin through calibration and validation. The performance of the model was assessed via calibration at gauging station using Relative Volume Error (D), coefficient of determination (R~(2)) and Nash-Sutcliffe Efficiency (NSE) performance coefficients. Then the model was validated using the parameters optimized during model calibration. The potential of surface water resources assessed at different watershed created to see at local level and finally at outlet point to Main River for sub-basin. The HEC-HMS model calibrated and validated at three gauging station in the sub basin which shows a good performance at Dabus near Asosa which resulted D=0.0066, R~(2)=0.91 and NSE=0.89 during calibration and D=4.9285, R~(2)=0.84 and NSE=0.82 during validation. The parameters optimized at Dabus were used for flow simulation to assess surface water resources potential on monthly and annual basis. The flow components were also separated at small catchment considered for the sub-basin during catchment delineation. The result shows that high percentage of flow occupied by baseflow for the sub basin. So the sub basin has high surface water potential which should be allocated fairly and accurately for water resources projects for effective utilization of the country water resources.