Assessment of the Impact of the Grand Ethiopian Renaissance Dam on the Performance of the High Aswan Dam

Abstract

A Large scale hydropower dam known as Grand Ethiopian Renaissance Dam (GERD) is under construction on the Blue Nile River just upstream of the Ethiopian-Sudan border in Ethiopia. The GERD has an active storage capacity of more than 60,000 Mm 3 and is anticipated to produce 6000 MW of hydropower energy. The aim of this study was to assess the potential impact of the dam on the performance of the High Aswan Dam (HAD) during filling and operation phases using a simulation model using Mike Basin river basin simulation model. The results indicate the planned 6 years filling period is sufficient to fill the reservoir with little impact on the current irrigation water demands from HAD in Egypt without additional management investment. There will be about 12% and 7% of reduction of annual energy output from High Aswan Dam during the filling and after filling stage of GERD respectively. Cumulative Energy production from the two dams will increase significantly Water loss at HAD due to evaporation will decreases by 22%. Overall performance of HAD during and after filling of the GERD remains at a reliability level of 96%. The study advises to utilize the results cautiously as it is based on only one historical realization of the many possible scenarios that may evolve in the future.

Management Scenarios of the Grand Ethiopian Renaissance Dam and Their Impacts under Recent and Future Climates

“…Hence, water losses from evaporation in the GERD are much smaller than in the HAD [4]. Mean annual losses from both reservoirs, HAD and GERD, may be 16% less than the loss from the HAD operating alone [21]. As projected climate change adds another dimension of uncertainties on future water availability and its variability, since some models project higher other lower rainfall and discharges [40], water storages may represent another adaptation option allowing for coordinated responses to changing boundary conditions or extreme situations [7].…”

“…After such events, Egypt may run short of water, if GERD and HAD are not carefully coordinated [7]. A high level of cooperation, particularly during reservoir filling may significantly reduce the adverse affects on Sudan and Egypt [7,21].…”

“…Mulat and Moges (2014) [21] argue that there will be only a small impact during a six-year filling period on irrigation management of the High Aswan Dam (HAD) in Egypt. According to Whittington et al (2014) [7], the filling of the GERD may adversely affect Egypt if it takes place in a sequence of dry years.…”

“…Some studies emphasize the potential negative impacts of the GERD on downstream discharges and that especially Egypt will suffer from lower hydroelectric power generation potential in the HAD and reduced revenues from irrigated agriculture [15,38,39]. Mulat and Moges (2014) [21] estimate a reduction of 7% in electricity generation of the HAD, once the GERD is online. Taye et al (2016) [4] on the contrary argue that, with the GERD online, the minimum annual net benefit for Sudan and Egypt may increase from $4.9-$5.6 billion in the agricultural and energy sector.…”

The Adoption of the Declaration of the Principles on the Grand Ethiopian Renaissance Dam and Lessons for South Asia

“…Egypt and Sudan are the largest water consumers while this is negligible for Ethiopia, even though 85% of the Nile waters come from Ethiopian highlands (Mulat and Moges, 2014). The vast irrigation systems in Egypt and to a lesser extent Sudan are wholly dependent on Nile water, whereas Ethiopia has developed less than five per cent of the irrigable land in the basin.…”