Following on from the previous post, a closer look at the environmental challenges associated with the damming projects on the river Nile can provide further insight into the different factors at work.
Whilst the Nile rivers contain many dams, I will be focusing on the interaction between the High Aswan Dam (HAD) in Egypt and the proposed Grand Ethiopian Renaissance Dam (GRED) in Ethiopia as these are the two water management systems that are the most important in affecting the hydrological flow of the Nile and subsequently changing the local environments. The interaction between the HAD and GRED systems is also of great geographic interest, as it is a transboundary issue reflecting the intersection between political, environmental and social challenges. Due to the amount of detail required for a comprehensive analysis of this issue, the post will be split into 2 separate entries, with the background information being provided here.
Figure 1: Geographic overview of the GERD and HAD systems along the Nile (Economist, 2020).
To study the impacts of the HAD and GERD projects, some background information is required. Both dams are responses to increases in population growth to deal with increased demand for water resources (
Henshaw & Paisley, 2013). The HAD was built between 1960-1970 to regulate extreme climactic variations affecting floods in the Nile Delta, and the GERD is proposed as a development scheme for hydro-electric power, irrigation and flood management. Under normal conditions, the environmental impact of the GERD is obvious in terms of wide scale alterations to the hydrological cycle and local environmental change both upstream and downstream. When increased climate variability is factored into this analysis, the environmental change from the GERD becomes even more apparent and is exemplified by different reservoir management procedures that will be necessary in the HAD (
Wheeler et al, 2016).
The HAD is colloquially known as the 'faucet' of the Egyptian Nile, essentially controlling the flow regime of the Lower Nile and Nile delta. It is vitally important in maintaining the current environmental conditions for agriculture along the Nile, supplying water to 86% of all crops in Egypt.
As the GERD is upstream of the HAD, it will have a degree of control over the flow regime of the HAD system and the lower Nile. Due to the pressures from the agricultural industry, this region is already under a significant level of water stress, indicated by the exploitation of the Nubian Aquifer system.
Although the GERD is upstream of the HAD, the situation is slightly more complicated as the Lower Nile is fed by the Blue and White Nile rivers, therefore the GERD only has control of 53% of the flow into the HAD (
Eldardiry & Hossain, 2020).
To analyse the potential environmental issues along the Nile associated with the GERD and HAD projects, different climactic and hydrological scenarios have been proposed in order to predict the changes in flow regimes and the subsequent impacts on the environment (
Eldardiry & Hossain, 2020). The specific details of this will be discussed in the next blog-post.
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