The Grand Ethiopian Renaissance Dam (GERD or TaIHiGe; Amharic: ታላቁ የኢትዮጵያ ሕዳሴ ግድብ, romanized: Tālāqu ye-Ītyōppyā Hidāsē Gidib), formerly known as the Millennium Dam and sometimes referred to as Hidase Dam (Amharic: ሕዳሴ ግድብ, romanized: Hidāsē Gidib), is a gravity dam on the Blue Nile River in Ethiopia under construction since 2011. The dam is in the Benishangul-Gumuz Region of Ethiopia, about 45 km (28 mi) east of the border with Sudan.
The primary purpose of the dam is electricity production to relieve Ethiopia’s acute energy shortage and for electricity export to neighboring countries. With a planned installed capacity of 6.45 gigawatts, the dam will be the largest hydroelectric power plant in Africa when completed, as well as the seventh largest in the world.
Filling the reservoir began in July 2020. It will take between 4 and 7 years to fill with water, depending on hydrologic conditions during the filling period and agreements reached between Ethiopia, Sudan, and Egypt
Facts about Grand Ethiopian Renaissance Dam
Are you curious about Grand Ethiopian Renaissance Dam (GERD) on Blue Nile River?GERD FACT SHEETHistorical Background: Prior to the upstream riparian countries agreement in 2010 there were some arguable, outdated colonial treaties that allocate all the Nile water to EGYPT and SUDAN only. – The 1902 treaty was the agreement between Britain on behalf of Sudan and Ethiopia. This agreement is being misinterpreted by Sudan and Egypt. The agreement prohibited construction of any work along Blue Nile which would arrest /obstruct its flow. GERD doesn’t arrest or obstruct the flow. After generating electricity it will continue to flow. As a matter of fact the Entebbe annuls the colonial era agreements. -In 1929 the Nile agreement was signed between Egypt and Britain, granting Egypt an absolute right and power to control any project along the Nile. -The 1959 agreement was between Egypt and Sudan. In addition to the previous agreement, this accord granted Egypt the right to 55.5 Billion cubic meters of Nile water a year and Sudan 18.5 Billion cubic meter water per year. In this agreement Egypt and Sudan gave absolute rights to themselves excluding all upstream countries. -Six out of ten Nile Basin Initiative stats have signed the Cooperative Framework Agreement which allows upstream countries to conduct projects along the river without prior consent of Egypt. General information and Benefits to Ethiopia-Ethiopia provides 85% Nile’s of water but receives Zero. Egypt has received the lion’s share. It is time Ethiopia uses its fair share of water that originates from its own land.-About 60% of Ethiopians don’t have access to electricity. Egypt has 100% electric access. -GERD reservoir capacity is 74 BCM of water – Estimated cost is about $5 Billion. 100% of the cost is covered by Ethiopia. GERD is a much needed project to Ethiopia. Why? -It will light up millions of homes -GERD will be a lifeline for millions out of poverty-It will generate 6000 MW to Ethiopian current electric generation capacity.-It is predicted Ethiopia will earn $1 billion from electricity sell to its neighbors.-Up to 7,000 tons of fish are expected to be harvested annually- The reservoir is about three times in volume than Lake Tana. It can be a good tourist destination.- Hundreds of millions of people use biomass energy, mainly wood to cook their daily food. When people have access to electricity, tremendous amounts of trees can be saved and deforestation will decrease enormously. -Hydroelectric Energy is clean, cheap, reliable and renewable. Once the dam is filled the water level remains constant. Benefits to Egypt and Sudan: -Regulated flow. This is convenient to control flood, hydroelectric power and irrigation.-t will retain silt that keeps downstream reservoirs water retaining capacity safe. That will prolongs the life time of dams in Sudan and Egypt – When flood is stored in GERD It will reduce evaporation loss by about 10 billion meter cube per year which could have been lost in Aswan dam. Evaporation loss in Aswan dam is four times higher.- GERD will supply cheaper electricity to neighboring countries including Egypt. Egypt’s excuses :A: Filling the dam and drought management-Egypt fear GERD will decrease its “historical” share.-Egypt wants a minimum annual flow of 40 BCM guaranteed. That means if Blue Nile river flow is below 40 BMC, they want us to release water from the reservoir. Our stand is a fair share at any time.- They request us to maintain 165m level of water.- Egypt wants to open office at the dam site so that it monitors the GERD operation-Egypt wants to command and lecture when we need to start filling the dam, how much water to fill at a time and how long the filling of the dam can take. -Ethiopia is filling the GERD only in the rainy season to avoid a significant harm to downstream countries. B: Safety Concern:Egypt raised its concerns about the safety of GERD. A team which consists of 5 international experts have examined the dam thoroughly and concluded that GERD is safe by any international measures.Team members who participated were from Germany (2), Egypt (1), Sudan (1) and Addis Ababa (1).C. Proximity to the Rift ValleyAfter the safety excuses was annulled by experts, Egypt raise a concern of earthquake on GERD due to its proximity to Rift Valley.The distance from Afar rift valley to GERD is approximately 500 Km while most earthquakes have no significant effect beyond 200 km. Egypt has wide Alternatives: Depriving of a fair water share to upstream countries can’t be a long run solution for Egypt. Egypt has plenty of alternatives to meet its water demand. If there is a will there’s a way!-Reducing evaporation water loss (GERD will play an important role in this regard)-Maximize use of its ground water (water wells)-Maximize use of rain water whenever it is available.-Sea water desalination (Egypt can utilize Red Sea and Mediterranean Sea) -Maximize water use efficiency (best irrigation and sewerage treatments.-Minimize the 12% evaporation loss using GERD.Source -Sisay Alemayehu fb page
“The benefits of the GERD”These are some facts about the Grand Ethiopian Renaissance Dam’s positive impacts for both Ethiopia and the other Nile Basin African countries. This is truly a unifying and vastly important mega project for Sub Saharan Africa and stands as a testimony of Africa’s continuous rise and her bright future. If you are interested in environmental sustainability issues in Ethiopia then make sure to follow this wonderful page with a wonderful team. GreenethiopiaEthiopian Next Generation#Addisfotofest#aff#dfaplc#destaforafrica#photography#africa #GERD #EthiopiaNileRights#مصر#itsmydam#اليوم_السابع#GERD#سد_النهضة#EgyptNileRights#اثيوبيا#BlackLivesMatter#FillTheDam#Ethiopia#Egypt #Nile #Habesha#GreenLegacy#environment#PMGreenLegacyChallenge#Sudan#eastafrica#linegaabaychallenge#aff2021#exhibition#Nile
Appropriate Naming and meanings of the River Abbay
The name of the river is derived from the Ge’ez word for ‘great’ to imply its being ‘the river of rivers’. The word Abay still exists in Ethiopian major languages to refer to anything or anyone considered to be superior.
The eventual site for the Grand Ethiopian Renaissance Dam was identified by the United States Bureau of Reclamation in the course of the Blue Nile survey, which was conducted between 1956 and 1964 during the reign of Emperor Haile Selassie. Due to the coup d’état of 1974, however, the project failed to progress. The Ethiopian Government surveyed the site in October 2009 and August 2010. In November 2010, a design for the dam was submitted by James Kelston.
On 31 March 2011, a day after the project was made public, a US$4.8 billion contract was awarded without competitive bidding to Italian company Salini Impregilo, and the dam’s foundation stone was laid on 2 April 2011 by then Prime Minister Meles Zenawi. A rock-crushing plant was constructed, along with a small air strip for fast transportation. The expectation was for the first two power-generation turbines to become operational after 44 months of construction, or early 2015.
Egypt, located over 2,500 kilometres downstream of the site, opposes the dam, which it believes will reduce the amount of water available from the Nile. Zenawi argued, based on an unnamed study, that the dam would not reduce water availability downstream and would also regulate water for irrigation. In May 2011, it was announced that Ethiopia would share blueprints for the dam with Egypt so that the downstream impact could be examined.
The dam was originally called “Project X”, and after its contract was announced it was called the Millennium Dam. On 15 April 2011, the Council of Ministers renamed it Grand Ethiopian Renaissance Dam. Ethiopia has a potential for about 45 GW of hydropower. The dam is being funded by government bonds and private donations. It was slated for completion in July 2017.
The potential impacts of the dam have been the source of severe regional controversy. The Government of Egypt, a country which relies heavily on the waters of the Nile, has demanded that Ethiopia cease construction on the dam as a precondition to negotiations, has sought regional support for its position, and some political leaders have discussed methods to sabotage it. Egypt has planned a diplomatic initiative to undermine support for the dam in the region as well as in other countries supporting the project such as China and Italy. However, other nations in the Nile Basin Initiative have expressed support for the dam, including Sudan, the only other nation downstream of the Blue Nile. Sudan has accused Egypt of inflaming the situation.
Ethiopia denies that the dam will have a negative impact on downstream water flows and contends that the dam will, in fact, increase water flows to Egypt by reducing evaporation on Lake Nasser. Ethiopia has accused Egypt of being unreasonable; Egypt is demanding to increase its share of the Nile’s water flow from 66% to 90%. In October 2019, Egypt stated that talks with Sudan and Ethiopia over the operation of a $4 billion hydropower dam that Ethiopia is building on the Nile have reached a deadlock. Beginning in November 2019, U.S. Secretary of the Treasury Steven T. Mnuchin began facilitating negotiations between the three countries.
Cost and financing
The Ethiopian government has stated that it intends to fund the entire cost of the dam by itself in order to prevent relying on foreign countries who may be brought under pressure by Egypt to withdraw their support. Ethiopia has issued a bond targeted at Ethiopians in the country and abroad to that end. The turbines and associated electrical equipment of the hydropower plants costing about US$1.8 billion are reportedly financed by Chinese banks. This would leave US$3 billion to be financed by the Ethiopian government through other means. The estimated US$4.8 billion construction cost, apparently excluding the cost of power transmission lines, corresponds to about 5% of Ethiopia’s gross domestic product of US$87 billion in 2017.
The design changed several times between 2011 and 2017. This affected both the electrical parameters and the storage parameters.
Originally, in 2011, the hydropower plant was to receive 15 generating units with 350 MW nameplate capacity each, resulting in a total installed capacity of 5,250 MW with an expected power generation of 15,128 GWh per year. Its planned generation capacity was later increased to 6,000 MW, through 16 generating units with 375 MW nominal capacity each. The expected power generation was estimated at 15,692 GWh per year. In 2017, the design was again changed to add another 450 MW for a total of 6,450 MW, with a planned power generation of 16,153 GWh per year.That was achieved by upgrading 14 of the 16 generating units from 375 MW to 400 MW without changing the nominal capacity.
Not only the electrical power parameters changed over time, but also the storage parameters. Originally, in 2011, the dam was planned to be 145 m (476 ft) tall with a volume of 10.1 million m³. The reservoir was planned to have a volume of 66 km3 (54,000,000 acre⋅ft) and a surface area of 1,680 km2 (650 sq mi) at full supply level. The rock-filled saddle dam besides the main dam was planned to have a height of 45 m (148 ft) meters, a length of 4,800 m (15,700 ft) and a volume of 15 million m³.
In 2013, an Independent Panel of Experts (IPoE) assessed the dam and its technological parameters. At that time, the reservoir sizes were changed already. The size of the reservoir at full supply level went up to 1,874 km2 (724 sq mi) (plus 194 km²). The storage volume at full supply level had increased to 74 km3 (60,000,000 acre⋅ft) (plus 7 km³). These numbers did not change after 2013.
After the IPoE made its recommendations, in 2013, the dam parameters were changed to account for higher flow volumes in case of extreme floods: a main dam height of 155 m (509 ft) (plus 10 meters) with a length of 1,780 m (5,840 ft) (no change) and a dam volume of 10.2 million m³ (plus 0.1 million m³). The outlet parameters did not change, only the crest of the main dam was raised. The rock saddle dam went up to a height of 50 m (160 ft) (plus 5 meters) with a length of 5,200 m (17,100 ft) (plus 400 meters). The volume of the rock saddle dam increased to 16.5 million m3 (plus 1.5 million m3).
The design parameters as of August 2017 are as follows, given the changes as outlined above:
The zero level of the main dam, the ground level, will be at a height of almost exactly 500 m (1,600 ft) above sea level, corresponding roughly to the level of the river bed of the Blue Nile. Counting from the ground level, the main gravity dam will be 145 m (476 ft) tall, 1,780 m (5,840 ft) long and composed of roller-compacted concrete. The crest of the dam will be at a height of 655 m (2,149 ft) above sea level. The outlets of the two powerhouses are below the ground level, the total height of the dam will, therefore, be slightly higher than that of the given height of the dam. In some publications, the main contractor constructing the dam puts forward a number of 170 m (560 ft) for the dam height, which might account for the additional depth of the dam below ground level, which would mean 15 m (49 ft) of excavations from the basement before filling the dam. The structural volume of the dam will be 10,200,000 m3 (13,300,000 cu yd). The main dam will be 40 km (25 mi) from the border with Sudan.
Supporting the main dam and reservoir will be a curved and 4.9 km (3 mi) long and 50 m (164 ft) high rock-fill saddle dam. The ground level of the saddle dam is at an elevation of about 600 m (2,000 ft) above sea level. The surface of the saddle dam has a bituminous finish, to keep the interior of the dam dry. The saddle dam will be just 3.3–3.5 km (2–2 mi) away from the border with Sudan, it is much closer to the border than the main dam.
The reservoir behind both dams will have a storage capacity of 74 km3 (60,000,000 acre⋅ft) and a surface area of 1,874 km2 (724 sq mi) when at full supply level of 640 m (2,100 ft) above sea level. The full supply level is therefore 140 m (460 ft) above the ground level of the main dam. Hydropower generation can happen between reservoir levels of 590 m (1,940 ft), the so-called minimum operating level, and 640 m (2,100 ft), the full supply level. The live storage volume, usable for power generation between both levels is then 59.2 km3 (48,000,000 acre⋅ft). The first 90 m (300 ft) of the height of the dam will be a dead height for the reservoir, leading to a dead storage volume of the reservoir of 14.8 km3 (12,000,000 acre⋅ft).
The dams will have three spillways. All using approximately 18,000 cubic meters of concrete. These spillways together are designed for a flood of up to 38,500 m3/s (1,360,000 cu ft/s), an event not considered to happen at all, as this discharge volume is the so-called ‘Probable Maximum Flood’. All waters from the three spillways are designed to discharge into the Blue Nile before the river enters Sudanese territory.
The main and gated spillway is located to the left of the main dam and will be controlled by six floodgates and have a design discharge of 14,700 m3/s (520,000 cu ft/s) in total. The spillway will be 84 m (276 ft) wide at the outflow gates. The base level of the spillway will be at 624.9 m (2,050 ft), well below the full supply level.
An ungated spillway, the auxiliary spillway, sits at the center of the main dam with an open width of about 205 m (673 ft). This spillway has a base-level at 640 m (2,100 ft), which is exactly the full supply level of the reservoir. The dam crest is 15 m (49 ft) higher to the left and to the right of the spillway. This ungated spillway is only expected to be used, if the reservoir is both full and the flow exceeds 14,700 m3/s (520,000 cu ft/s), a flow value, that is expected to be exceeded once every ten years.
A third spillway, an emergency spillway, is located to the right of the curved saddle dam, with a base level at 642 m (2,106 ft). This emergency spillway has an open space of about 1,200 m (3,900 ft) along its rim. This third spillway will carry water only if the conditions for a flood of more than around 30,000 m3/s (1,100,000 cu ft/s) are given, corresponding to a flood to occur only once every 10,000 years.
Power generation and distribution
Flanking either side of the auxiliary ungated spillway at the center of the dam will be two power houses. The right will contain 10 x 375 MW Francis turbine-generators, the left power house will house 6 x 375 MW of the same turbine-generators. 14 of the 16 turbine-generators have been upgraded to 400 MW without changing the nameplate capacity (which is still at 375 MW), while two turbine-generators remained at 375 MW.The total installed capacity with all turbine-generators will be 6,450 MW. The average annual flow of the Blue Nile being available for power generation is expected to be 1,547 m3/s (54,600 cu ft/s), which gives rise to an annual expectation for power generation of 16,153 GWh, corresponding to a plant load factor (or capacity factor) of 28.6%.
The Francis turbines inside the power houses are installed in a vertical manner, raising 7 m (23 ft) above the ground level. For the foreseen operation between the minimum operating level and the full supply level, the water head available to the turbines will be 83–133 m (272–436 ft) high. A switching station will be located close to the main dam, where the generated power will be delivered to the national grid. Four 500 kV main power transmission lines were completed in August 2017, all going to Holeta and then with several 400 kV lines to the metropolitan area of Addis Ababa. Two 400 kV lines run from the dam to the Beles Hydroelectric Power Plant. Also planned are 500 kV high-voltage direct current lines.
Early power generation
Two non-upgraded turbine-generators with 375 MW each are the first to go into operation with 750 MW delivered to the national power grid. This early power generation will start well before the completion of the dam, when the filling of the reservoir commences. The two units sit within the 10 unit powerhouse to the right side of the dam at the auxiliary spillway. They are fed by two special intakes within the dam structure that are located at a height of 540 m (1,770 ft) above sea level. It is foreseen, that power generation can start at a water level of 560 m (1,840 ft), 30 m (98 ft) below the minimum operating level of the other 14 turbine-generators. At that level, the reservoir has been filled with roughly 5.5 km3 (1.3 cu mi) of water, which corresponds to roughly 11% of the annual inflow of 48.8 km3 (11.7 cu mi). During the rainy season, this is expected to happen within days to weeks. First stage filling of the reservoir for early generation was complete on 20 July 2020.
Satellite image of the reservoir on 26 October 2020
Two “bottom” outlets at 542 m (1,778 ft) above sea level or 42 m (138 ft) above the local river bed level are available for delivering water to Sudan and Egypt under special circumstances, in particular for irrigation purposes downstream, if the level of the reservoir falls below the minimum operating level of 590 m (1,940 ft) but also during the initial filling process of the reservoir.
The space below the “bottom” outlets is the primary buffer space for alluvium through siltation and sedimentation. For the Roseires Reservoir just downstream from the GERD site, the average siltation and sedimentation volume (without GERD in place) amounts to around 0.035 km3 (28,000 acre⋅ft) per year. Due to the large size of the GERD reservoir, the siltation and sedimentation volume is expected to be much higher in this case, 0.21 km3 (170,000 acre⋅ft) per annum. The GERD reservoir will foreseeably take away the siltation threat from the Roseires reservoir almost entirely.
The base of the GERD dam is at around 500 m (1,600 ft) above sea level. Water flowing out of the dam will be released into the Blue Nile again which will flow for only around 30 km (19 mi), before joining the Roseires reservoir, which – if at full supply level – will be at 490 m (1,610 ft) above sea level. There is only a 10 m (33 ft) elevation difference between both projects. The two reservoirs and accompanying hydropower projects could – if coordinated properly across the border between Ethiopia and Sudan – become a cascaded system for more efficient hydropower generation and better irrigation (in Sudan in particular). Water from the 140 m (460 ft) column of the water storage of the GERD reservoir could be diverted through tunnels to facilitate new irrigation schemes in Sudan close to the border with South Sudan. In Ethiopia itself, no irrigation schemes are planned due to the proximity of the dam to the downstream border with Sudan.
Evaporation of water from the reservoir is expected to be at 3% of the annual inflow volume of 48.8 km3 (11.7 cu mi), which corresponds to an average volume lost through evaporation of around 1.5 km3 (0.36 cu mi) annually. This was considered negligible by the IPoE. For comparison, Lake Nasser in Egypt loses between 10–16 km3 (2.4–3.8 cu mi) annually through evaporation.
The main contractor is the Italian company Webuild (formerly Salini Impregilo), which also served as primary contractor for the Gilgel Gibe II, Gilgel Gibe III, and Tana Beles dams. Simegnew Bekele was the project manager of GERD from the start of construction in 2011 up to his death on 26 July 2018. The dam is expected to consume 10 million metric tons of concrete. The government has pledged to use only domestically produced concrete. In March 2012, Salini awarded the Italian firm Tratos Cavi SPA a contract to supply low- and high-voltage cable for the dam. Alstom will provide the eight 375 MW Francis turbines for the project’s first phase, at a cost of €250 million. As of April 2013, nearly 32 percent of the project was complete. Site excavation and some concrete placement was underway. One concrete batch plant has been completed with another under construction. Diversion of the Blue Nile was completed on 28 May 2013 and marked by a ceremony the same day. By January 2016 the dam had 4 million cubic meters of concrete poured, and the installation of the first two turbines was imminent. The first power production of 750 MW was slated for sometime later that year.
In October 2019, the work was approximately 70% complete. As of March 2020, the steelworks reached 35% complete, civil works are 87% complete while electro-mechanical works are 17% complete, to attain in total 71% construction complete according to Belachew Kasa, Project Deputy Director.
On 26 June 2020, Egypt, Sudan, and Ethiopia agreed to delay filling the dam for a few weeks.
On 21 July 2020, Ethiopian prime minister, Abiy Ahmed, announced that the first filling of the dam has been completed. The early filling of the dam was attributed to the heavy rains. In his statement, Abiy stated that “We have successfully completed the first dam filling without bothering and hurting anyone else. Now the dam is overflowing downstream”. The target for the first year filling was 4.9 billion cubic meters, while the dam has capacity to hold 74 billion cubic meters when completed.
The first phase of filling the reservoir began in July 2020, to a maximum depth of 70 metres (230 ft) utilising a temporary sill. Further construction work is necessary before the dam can be filled to a level for electricity generation.
In February 2021, Ethiopian Minister of Water and Irrigation, Selchi Bakli, mentioned that the engineering work in constructing the dam reached 91%, while the total construction rate was 78.3%.
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