Please enter verification code
Hydrological Impacts of the Grand Ethiopian Renaissance Dam (GERD) on River Nile Hydrology Within Sudan
Volume 8, Issue 3, September 2020, Pages: 41-51
Received: Apr. 11, 2020; Accepted: Sep. 1, 2020; Published: Sep. 19, 2020
Views 236      Downloads 151
Mansour Ahmed Mordos, Water and Reservoir Directorate, Merowe Dam, Merowe, Sudan
El Sadig Abdellah Sharfi, Department of Civil Engineering, University of Khartoum, Khartoum, Sudan
Bouran Awadh Mohammed, Department of Civil Engineering, University of Khartoum, Faculty of Engineering, Khartoum, Sudan
Kevin Wheeler, Environmental Change Institute, University of Oxford, Oxford, UK
Article Tools
Follow on us
This paper aims to quantify the potential impacts of the Grand Ethiopian Renaissance Dam (GERD) on the River Nile System within Sudan territories, in the context of hydrology. GERD reservoir with a capacity of (74 Km3) is approximately 1.5 times the mean annual flow of the Blue Nile, which contributes by 57% of the River Nile runoff. According to Ethiopian proposal, the GERD is going to be filled to the full supply level of 640 m a.m.s.l in 6 to 7 years. The first filling of GERD reservoir was planned to be in 2014, but it is postponed until the writing of this report. However, it's most likely to be started this year 2020. Consequently, significant impacts are highly anticipated during this first filling period, and all over the long-term operation. Definitely, this will change the Blue and Main Nile hydrological regime. In order to achieve the research objectives, a daily time step Rule Based Simulation model has been developed using River Ware Software (University of Colorado) representing the entire River Nile system within Sudan. Three scenarios were adopted, baseline (Hydrological System without GERD), GERD first filling and long-term operation. River inflows, water levels, run-off and hydrograph shapes within Sudan water system were investigated and compared to the average baselines, taking into consideration the recent Dams’ operation policies and rules. In addition, a simple-approach operation scenario was adopted for GERD. Likewise, as hydrological inputs, 30 years of historical time series were used. Given the above, the hydrological impacts in six representative River Nile reaches within Sudan were estimated, then highlighted and judiciously investigated. In summary, it could be concluded that, during the first filling of GERD, the runoff of the Blue Nile will decrease by 30%. While, for the Long Run, significant changes are expected for to the Blue Nile hydrograph, resulting in slight to moderate changes for the Main Nile Hydrograph. It’s expected that the impacts of GERD on River Nile hydrology will lead to increasing average discharges during summer period by a range of 10 - 500% for different months and hydrology, on the other hand, reducing flood peak by approximately 10-25%. In the long run, Water Levels in different reaches are expected to vary by ± (2 to 3) meters. It's concluded that operation policies of the existing Sudanese dams will no longer be valid for the new Situation after GERD, further studies are highly recommended to be conducted.
GERD, River Nile, Hydrological Impacts, River Ware, Hydrograph, Water Level, Run-Off
To cite this article
Mansour Ahmed Mordos, El Sadig Abdellah Sharfi, Bouran Awadh Mohammed, Kevin Wheeler, Hydrological Impacts of the Grand Ethiopian Renaissance Dam (GERD) on River Nile Hydrology Within Sudan, Hydrology. Vol. 8, No. 3, 2020, pp. 41-51. doi: 10.11648/j.hyd.20200803.12
Copyright © 2020 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Ministry of Water Resources and Electricity, Ethiopia (May, 2013), "International Panel of Experts Report on GERD," Addis Ababa, Ethiopia.
Merowe Dam Electricity Company (MDEC) (2013), "Rosaires Efect on Merowe Dam Generation," Merowe, Sudan.
André Alberto Weber (2013), et al, "Downstream impacts of a dam and influence of a tributary on the reproductive success of Leporinus reinhardti," AQUATIC BIOLOGY, pp. Vol. 19: 195–200, 2013. Retrieved March 2018.
G. P. Williams, and M. G. Wolman (1984), "Downstream effects of dams on alluvial rivers," United States Geological Survey Professional Paper 1286, Washington, DC: US Government Printing Office.
Paweł Marcinkowski and Mateusz Grygoruk (2017), "Long-Term Downstream Effects of a Dam on a Lowland River Flow Regime: Case Study of the Upper Narew," Water, vol. Adaptive Catchment Management and Reservoir Operation.
Alan Nicol, Mamdouh Shahin (2003), "The Nile: moving beyond cooperation," UNESCO, PCCP.
Claudia Kuenzer, et al. (2012), "Understanding the impact of hydropower developments in the context of upstream–downstream relations in the Mekong river basin," Sustainability Science.
Lu X, Wang J, Grundy-Warr (2008), "Are the Chinese dams to be blamed for the lower water levels in the lower Mekong? In: Kummu M, Keskinen M, Vairs O (eds) Modern myths of the Mekong," Water & Development Publications, p. 39–54.
Chapman EC, He D (1996), "Downstream implications of Chinas dams on the Lancang Jiang (Upper Mekong) and their potential significance for greater regional cooperation," Sydney, Australia.
Shokhrukh-Mirzo Jalilov (2010), "IMPACT OF ROGUN DAM ON DOWNSTREAM UZBEKISTAN AGRICULTURE," Fargo, North Dakota.
T. E. COYNE ET BELLEIR (2011), "Grand Ethiopian Renaissance Dam Project Impounding and Operation Simulations Impact Study on High Aswan Dam," HYDROLOGICAL AND RESERVOIR SIMULATION STUDIES, Addis Ababa, Ethiopia.
(March 2017), [Online]. Retrieved from RiverWare Website:
(May 2017) "World Atlas," [Online], Retrieved from Infographic © Codi Yeager-Kozacek / Circle of Blue.
(January 2017), [Online]. Retrieved from RiverWare Website:
Science Publishing Group
1 Rockefeller Plaza,
10th and 11th Floors,
New York, NY 10020
Tel: (001)347-983-5186