Water Resources Engineering (WRE) connects engineering hydrology and hydraulics with global, economic, environmental, and societal issues. Our student Katja Fiertz makes this connection here…

The article “Egypt and Ethiopia Spar over the Nile” was uploaded to Al Jazeera on February 6, 2014[1]. The article relates to the WRE domain of hydrology in terms of distribution of water along the Nile and the domain of hydraulics in terms of the fluid mechanics that make building a dam desirable. Ethiopia, the main source of the Nile, is currently planning to build a $4.2 billion dam that would produce 6,000 megawatts of electricity, on the Blue Nile River, the main tributary of the Nile. Egypt is concerned that this dam may reduce the flow of water that reaches them1. Since the Nile is the source of 95% of Egypt’s water1, a reduction in flow could result in water shortages, which Egypt is already concerned about even without the dam1. In 1959, Egypt and Sudan, without consulting the other counties of the Nile basin, signed a contract that allocated 66% of the Nile’s water to Egypt, but due to a growing population, Egypt has requested that their allocation be increased to 95%1. Ethiopia claims that not only will the dam not decrease the flow in the river; it will actually increase flow by decreasing evaporation downstream1. The claims of Ethiopia that the dam will not decrease downstream flow in any way are unlikely, especially given that there is no study supporting that claim. While the article states that the dam would decrease evaporation and improve water flow, there is no clear way that the dam would do this. The Nile has a “permanent precipitation deficit in relation to potential evaporation across most of its basin”[2]. The addition of another reservoir would likely increase evaporation. For example, Lake Nasser, a natural lake in Egypt with an area of 6500 km­2 has an annual average evaporation of 3000 mm, which is equivalent to 10% of its overall reservoir storage, 10% of average annual river flow, or 50% of the total discharge by the Nile at low flow1. Additionally, the Nile has very variable flow, 80% of its flow occurs during the wet season months from July to October and only 4% of the flow occurs during the dry season months of February to May[3]. A dam could change the variability of the flow, which would change how it can be used downstream. As Pacini et al. stated “[w]ater storage can be expected to increase water temperature, fuelling yet higher evaporative losses and affecting freshwater species”1. This article did not address the expected size of the reservoir behind the dam or the current plans for the rate of outflow from the dam. Both of these pieces are crucial in calculating the effects on flow of the given dam.

Not only does the issue of the dam effect the hydrology of the area, but it also effects the economics of the region, particularly in Ethiopia, the environment around and downstream of the dam, the society of people living in the region, and the political relationship between Ethiopia and Egypt. The dam will bring a reliable source of energy to the region, which could allow more development to occur. Selling electricity to surrounding countries is expected to provide Ethiopia with a source of income. The dam and reservoir will change the current environment into a different ecosystem and change the flow of the river in that area4. This change in the ecosystem will change the livelihoods of the people who currently live on subsidence farming and agriculture[4]. In addition, the creation of the reservoir will displace approximately 20,000 people3. It will affect Ethiopia and Egypt’s relationship because Ethiopia feels that they need this dam to help alleviate poverty and Egypt feels that the dam must be stopped because the flow of the Nile provides the vast majority of their water and they worry about the dam’s effects on this water1. Furthermore, Ethiopia feel that they have a right to dam the water as they are the source of the Nile, currently claim minimal water from it, and have very few hydrologic developments on it2. Egypt feels that they have a right to the water because of a treaty signed between themselves and Sudan in 19591. As Ethiopia was not consulted on this treaty, they do not feel a compelled to honor it1. The negotiations between the two countries are particularly complicated due to the unrest in the area. Sudan was also opposed to the building of the dam, but since South Sudan recently succeeded, in part due to the support of Ethiopia, Sudan recently withdrew its opposition1. Egypt is also currently in a period of turmoil as its entire government has been overthrown within the timeframe of the dam’s planning. This makes it harder to Egypt to show a united position on the building of the dam.

Map of the Nile and site of proposed dam1

Figure 1. Map of the Nile and site of proposed dam1

Figure 2: Rendering of the proposed dam and reservoir

Figure 2: Rendering of the proposed dam and reservoir

[1] Hussein H. Egypt and Ethiopia spar over the Nile. Al Jazeera. http://america.aljazeera.com/opinions/2014/2/egypt-disputes-ethiopiarenaissancedam.html Published February 6, 2014. Accessed February 21, 2014.

[2] Pacini N, Donabaum K, de Villenueve P, Water-quality management in a vulnerable large river: the Nile in Egypt. International Journal of River Basin Management. 2013; 11: 205-219. doi: 10.1080/15715124.2013.781032

[3] McCartney M, Girma M, Evaluating the downstream implications of planned water resource development in the Ethiopian portion of the Blue Nile River. Water International. 2012; 37: 362-379. doi: 10.1080/02508060.2012.706384

[4]Veilleux JC. The human security dimensions of dam development: The grand Ethiopian Renaissance Dam. Global Dialogue. 2013; 15. http://www.transboundarywaters.orst.edu/publications/publications/Veilleux_GLOBAL%20DIALOGUE_V15_GERD.pdf. Accessed February 6, 2014.

[5]International rivers: The Grand Ethiopian Renaissance Dam fact sheet. http://www.internationalrivers.org/resources/the-grand-ethiopian-renaissance-dam-fact-sheet-8213. Updated 2014. Accessed February/21, 2014.