Abay
Abay is a mapped river in the YearMaps hydrographic index. Grand Ethiopian Renaissance Dam (GERD) stands on this watercourse and is written up below. River courses organise settlement, agriculture and frontier-making more durably than any political boundary, and this reach is indexed against the dams, lakes and cities within its catchment.
- Feature Class
- River
- Dams Recorded
- 1
- Coordinates
- 11.43°, 37.02°
About Abay
The Blue Nile is a river originating at Lake Tana in Ethiopia. It travels for approximately 1,450 km (900 mi) through Ethiopia and Sudan. Along with the White Nile, it is one of the two major tributaries of the Nile and supplies about 85.6% of the water to the Nile during the rainy season.
Encyclopedic summary adapted from Wikipedia: Blue Nile (CC BY-SA 4.0).
Abay in Depth
Course
The distance of the river from its source to its confluence has been variously reported between 1,460 and 1,600 kilometres (910 and 990 mi). This uncertainty might result from the fact that the river flows through a series of virtually impenetrable gorges cut in the Ethiopian Highlands to a depth of some 1,500 metres (4,900 ft). According to materials published by the Central Statistical Agency, an Ethiopian government agency, the Blue Nile has a total length of 1,450 kilometres (900 mi), of which 800 kilometres (500 mi) are inside Ethiopia.
The Blue Nile originates at Gish Abay at Sekela in Ethiopia (where it is called the Abay River).
History
The Egyptian fear that Ethiopia might block the Blue Nile was a major factor in the long and complex Ethiopian-Egyptian relationship. While Egypt relied on Ethiopia for its waters, Ethiopia depended on the Coptic Orthodox Patriarchate of Alexandria for patriarchal authority and the appointment of its metropolitan. This interdependence has shaped events since the 11th century. For centuries, the threat of blocking the Blue Nile was an effective strategy in ensuring the appointment of Egyptian metropolitans. However, in practice, neither a diversion nor large-scale use of the river's waters was ever attempted.
Sections adapted from Wikipedia: Blue Nile (CC BY-SA 4.0).
Abay: Key Facts
| Length | 1,783 km |
|---|---|
| Average discharge | 1,525 m³/s |
| Drainage basin | 325,000 km² |
| Source | Lake Tana |
| Mouth | Nile |
| Drainage system | Nile basin |
| Tributaries | Beles River, Didessa River, Bashilo River, Rahad River, Dinder River, Dabus River, Guder River, Gulla |
Facts from Wikidata Q882739 (CC0).
Grand Ethiopian Renaissance Dam (GERD)
Grand Ethiopian Renaissance Dam (GERD)
Roller-compacted Concrete dam · Benishangul-Gumuz, Ethiopia
Grand Ethiopian Renaissance Dam (GERD) is a roller-compacted concrete dam on the Blue Nile in Benishangul-Gumuz, Ethiopia, standing 145 m (476 ft) high and completed in 2023. It carries an installed hydroelectric capacity of 5,150 MW. The structure impounds GERD Reservoir.
The Grand Ethiopian Renaissance Dam (GERD or TaIHiGe; Amharic: ታላቁ የኢትዮጵያ ሕዳሴ ግድብ, romanized: Tālāqu ye-Ītyōppyā Hidāsē Gidib, Tigrinya: ግድብ ሕዳሰ ኢትዮጵያ, Oromo: Hidha Guddicha Haaromsa Itoophiyaa), formerly known as the Millennium Dam and sometimes referred to as the Hidase Dam (Amharic: ሕዳሴ ግድብ, romanized: Hidāsē Gidib, Oromo: Hidha Hidāsē), is a gravity dam on the Blue Nile River in Ethiopia. The dam is in the Metekel Zone of the Benishangul-Gumuz Region, close to the border with Sudan.
Constructed between 2011 and 2025, the dam's primary purpose is electricity production to relieve Ethiopia's acute energy shortage and to export electricity to neighbouring countries. With an installed capacity of 5.15 gigawatts, the dam is the largest hydroelectric power plant in Africa and among the 20 largest in the world.
The first phase of filling the reservoir began in July 2020 and in August 2020 the water level rose to an altitude of 540 metres (40 metres higher than the bottom of the river, which is at an altitude of 500 metres above sea level). The second phase of filling was completed on 19 July 2021, with water levels rising to an altitude of around 575 metres.
Adapted from Wikipedia: Grand Ethiopian Renaissance Dam (CC BY-SA 4.0).
- Dam type
- Roller-compacted Concrete
- Structural height
- 145 m (476 ft)
- Installed capacity
- 5,150 MW
- Impounded river
- Blue Nile
- Reservoir
- GERD Reservoir
- Location
- Benishangul-Gumuz, Ethiopia
- Year completed
- 2023
- Height rank
- #33 of 115 indexed
- Output rank
- #15 of 102 indexed
- Coordinates
- 11.2158°, 35.0936°
Notable: Africa's largest hydroelectric power plant; central to diplomatic negotiations with Egypt and Sudan.
Among the 115 dams indexed in YearMaps, Grand Ethiopian Renaissance Dam (GERD) ranks #33 by structural height, behind Jinping-I Dam (305 m). By installed generating capacity it ranks #15, behind Three Gorges Dam (22,500 MW).
Nearest cities: Ad Damazīn (102 km), Asosa (142 km), Gimbi (242 km).
More about Grand Ethiopian Renaissance Dam (GERD)
Background
The name that the Blue Nile river takes in Ethiopia ("Abay") 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 site chosen 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. However due to the coup d'état of 1974, Somalia's invasion of Ethiopia in 1977–78, and the 15-year-long Ethiopian Civil War, the project did not progress until the early 2000s. The Ethiopian Government surveyed the site in October 2009 and August 2010.
Construction
The main GERD 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. In October that year, he was replaced by Kifle Horo. The dam required 10 million m³ of concrete, for which the government pledged to use only domestic production. In March 2012, Salini awarded the Italian firm Tratos Cavi SPA a contract to supply low and high voltage cable for the dam. Alstom provided the eight Francis turbines for the project's first phase, at a cost of €250 million.
Design
The design changed several times between 2011 and 2019. This affected both the electrical and 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.
Sections adapted from Wikipedia: Grand Ethiopian Renaissance Dam (CC BY-SA 4.0).
Grand Ethiopian Renaissance Dam (GERD): Key Facts
| Crest length | 1,780 m |
|---|
Facts from Wikidata Q1542454 (CC0).
Major River Dossiers
Hand-written studies of the great river systems of history.
Connected Reaches
Nearby watercourses in the same drainage network.
Water Bodies in the Catchment
Settlements Along the Reach
Hydraulic Infrastructure Nearby
Surrounding Terrain
Abay: Quick Answers
- Where is Abay?
- Abay is located in Ethiopia, at 11.4324° N, 37.0171° E.
- Are there dams on the Abay?
- Yes. YearMaps records one dam on the Abay: Grand Ethiopian Renaissance Dam (GERD).
- How tall is Grand Ethiopian Renaissance Dam (GERD)?
- Grand Ethiopian Renaissance Dam (GERD) is 145 metres (476 ft) high and was completed in 2023.