STREAMFLOW FORECASTING AND RESERVOIR OPERATION UNDER CLIMATE CHANGE; A CASE STUDY IN THE GENALE DAWA III DAM, GENALE-DAWA RIVER BASIN, ETHIOPIA

Abstract

This study attempts to investigate potential impacts of future climate change on stream flow and reservoir operation on Genale sub-basin watershed. For this study, 0.5° x 0.5° grid resolution of bias-corrected (RCM) Regional Climate Model outputs based on Representative Concentration Pathways (RCP4.5) emissions scenario for Genale catchment are used for analysis. A Geographic Information System (GIS) companion product called the Geospatial Hydrologic Modeling Extension (HEC-GeoHMS) has been developed to aid in the creation of basin models and meteorological models to use the Hydrologic Engineering Center‟s Hydrologic Modeling System (HEC-HMS) model for generating future stream flows and Hydrologic Engineering Center‟s Reservoir Simulation Model (HEC-ResSim) was used for reservoir simulation and operation study. Simulation results demonstrate the average monthly power production of Genale Dawa-3 Hydropower project will not be affected in the future due to the inflow to the reservoir. Hence, the flow for power production according to the design document will be fully meeting the required amount.