Long-term potential impact of Great Ethiopian Renaissance Dam (GERD) on the downstream eastern Nile High Aswan Dam (HAD)

The Ethiopian government is undertaking the construction of Grand Ethiopian Renaissance Dam (GERD), the largest hydroelectric power plant in Africa with a storage volume corresponding to approximately 74 Billion Cubic Meters of water at the full supply level and is expected to produce 6000 MW power. The dam is located upstream of the Ethiopian–Sudan borders to utilize the water resources potential, and energy security to reduce poverty, but is controversially debated in the public and the scientific literature. The main objective of this research is to find out the extents of the long-term potential impact of the introduction of new upstream reservoir, GERD, on the downstream High Aswan Dam (HAD) of the Nile waters using the MODSIM simulation model. For model calibration and validation using the monthly flow data of 1956–2003, a good agreement was observed between simulated and gauged data at Dongola and Tamaniat stations. The correlation coefficient R² values for those stations were found to be more than 0.92 for each station. Due to the presence of GERD, the energy production of Egypt from HAD will decline by 5.243%, but in contrast GERD will create additional energy of 15,000 GWh/year for the eastern Nile power grid system. The loss of water due to evaporation decreases significantly by 9.922%. This GERD will affect the inflow amount which is reached on Egypt by 2.755% and the reservoir storage elevation will not affect at much as expected (which fluctuates with range of 0.609%).