Home / World / Ethiopian River Nile Dam: How It Will Be Filled

Ethiopian River Nile Dam: How It Will Be Filled



The large Ethiopian Renaissance dam (Gerd) was depicted in September 2019

Image copyright
Reuters

caption

This photo shows the pond at the end of the 201

9 rainy season

Satellite images taken between 27 June and 12 July 2020 show a steady increase in the amount of water held back by the new mega dam, which stretches across the Nile in Ethiopia.

This has angered Egypt and Sudan, the two countries downstream of the Great Ethiopian Renaissance Dam (Gerd), as the timetable for filling it has not yet been agreed in dead talks.

Interactive

A large container begins to form behind the pond

July 12, 2020

Satellite image showing the river Nile from the top in northwestern Ethiopia, July 12

June 26, 2020

Satellite image showing the river Nile from above in northwestern Ethiopia, June 26

State media in Ethiopia have traced back to reports that indicated that the dam was deliberately filled.

But all this gives the false impression that filling the pond will be like filling a bath – and that Ethiopia can turn on and off a tap at any time.

Can’t it be stopped?

No. The container behind the dam will be filled naturally during Ethiopia’s rainy season, which began in June and lasts until September.

Given the stage that the construction is on “there is nothing that can stop the container from filling to the lady’s low point”, said Dr Kevin Wheeler, who has followed the Gerd project of 4 billion dollars (£ 3.2 billion since 2012). BBC.

Explore the Nile with 360 video

a 360-degree version of the Damming the Nile VR series from BBC News

Media playback is not supported on your device

Alastair Leithead and his team traveled in 2018 from the Blue Nile source to the sea – through Ethiopia and Sudan into Egypt.

From the beginning of the process in 2011, the dam was built around the Blue Nile when it continued to flow through the huge construction site.

Builders worked with the large structures on either side of the river without any problems. In the middle, during the dry season, the river was diverted through culverts, or pipes, to allow this part to be built up.

The bottom of the middle section is now clear and the river is currently flowing through bypass channels at the foot of the wall.

When the rainy season is affected at the dam site, the amount of water that can pass through these canals will soon be less than the amount of water that enters the area, which means that it will be backed up further and add to the lake that will sit behind the dam, says Dr Wheeler .

The Ethiopian authorities may close the gates on some of the canals to increase the amount of water held back, but this may not be necessary, he says.

What is the next step?

During the first year, Gerd will retain 4.9 billion cubic meters (bcm) of water that will take it up to the height of the lowest point on the dam wall, allowing Ethiopia to test the first set of turbines. On average, the total annual flow of Blue Nile is 49bcm.

During the dry season, the lake will disappear a bit, which means that the dam wall can be built up and during the second year, an additional 13.5 cm will be retained.

You may also be interested in:

At that time, the water level should have reached the second set of turbines, which means that the water flow can be handled more consciously.

Ethiopia says it will take between five to seven years to fill the dam to its maximum flood season capacity of 74bcm. At that point, the lake that is created can extend about 250 km upstream.

Between each subsequent flood season, the container is lowered to 49.3bcm.

So why is Egypt unhappy?

Egypt, which relies almost entirely on the Nile for its water needs, is concerned that for most years of filling, a specific volume is not guaranteed.

Image copyright
Reuters

caption

Sudan and Egypt are worried about the river of the Nile in the coming years of drought

And when the filling stage is over, Ethiopia is reluctant to be tied to a figure of how much water is to be discharged when the dam is fully operational, and the dam will be the largest hydroelectric plant in Africa.

This year with normal or above average precipitation which should not be a problem, but Egypt is nervous about what can happen during prolonged droughts that can last for several years.


Source link