Grootdraai Dam
Encyclopedia
Grootdraai Dam is a dam on the Vaal River
, near Standerton
, Mpumalanga
, South Africa
. It was established in 1981.
Grootdraai Dam is a composite structure comprising a central concrete gravity section 360m long and two earthfill flanks giving a total crest length of 2 180m and a maximum wall height of 42m above lowest foundation level. The dam was completed in 1982 and was built primarily to support the water needs of the SASOL I, II and III coal to petrol plants at Secunda, ESKOM's, Tutuka Power Station
as well as the Matla Power Station
, Duvha Power Station
, Kendal Power Station
and Kriel Power Station
located on the coal fields in the adjacent Olifants River basin.
The dam also provides some flood attenuation for Standerton and stores up to 100 million m3/annum pumped into the upper reaches of the Vaal River basin from Heyshope Dam
in the Usutu River basin.
During the serious drought of 1983, the water resources in the adjacent Komati River
and Usutu River basins were badly depleted, leading to serious concerns that the water supplies to various power stations could be affected. Any water shortages to the power stations would be disastrous for South Africa
since 80% of the country's electricity is dependent on water from the Komati-Usutu-Vaal system. It was estimated that the newly completed (1982) Grootdraai Dam would empty within a matter of months and an emergency scheme was therefore initiated to pump water upstream over a distance of 202 km to Grootdraai Dam from Vaal Dam
. The emergency scheme involved constructing 7 weirs, each with numerous pumps capable of pumping a total of 1 million m3/day. Although the emergency scheme was never used, it was completed and received an award for the Most Outstanding Civil Engineering Achievement of 1983 from the South African Institute of Civil Engineers.
Vaal River
The Vaal River is the largest tributary of the Orange River in South Africa. The river has its source in the Drakensberg mountains in Mpumalanga, east of Johannesburg and about 30 km north of Ermelo and only about 240 km from the Indian Ocean. It then flows westwards to its conjunction...
, near Standerton
Standerton
Standerton is a large commercial and agricultural town lying on the banks of the Vaal River in Mpumalanga, South Africa which specialises in cattle, dairy, maize and poultry farming. The town was established in 1876 and named after Boer leader Commadant AH Stander. During the Second Boer War a...
, Mpumalanga
Mpumalanga
Mpumalanga , is a province of South Africa. The name means east or literally "the place where the sun rises" in Swazi, Xhosa, Ndebele and Zulu. Mpumalanga lies in eastern South Africa, north of KwaZulu-Natal and bordering Swaziland and Mozambique. It constitutes 6.5% of South Africa's land area...
, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
. It was established in 1981.
Grootdraai Dam is a composite structure comprising a central concrete gravity section 360m long and two earthfill flanks giving a total crest length of 2 180m and a maximum wall height of 42m above lowest foundation level. The dam was completed in 1982 and was built primarily to support the water needs of the SASOL I, II and III coal to petrol plants at Secunda, ESKOM's, Tutuka Power Station
Tutuka Power Station
Tutuka Power Station in Mpumalanga, South Africa, is a coal-fired power plant operated by Eskom.-History:The first unit at Tutuka was commissioned in June 1985 and the last went online in June 1990.-Power station:...
as well as the Matla Power Station
Matla Power Station
Matla Power Station in Mpumalanga, South Africa, is a coal-fired power plant operated by Eskom.- See also :* Eskom* Fossil-fuel power plant* List of power stations in South Africa...
, Duvha Power Station
Duvha Power Station
Duvha Power Station in Mpumalanga, South Africa, is a coal-fired power plant operated by Eskom. The tall chimneys at Duvha are the tallest structures in Africa.-History:...
, Kendal Power Station
Kendal Power Station
-Power generation:Power generation is done by six 686 MW units for a total installed capacity of 4,116 MW. Turbine Maximum Continuous Rating is 16.67%- See also :* Eskom* Fossil-fuel power plant* List of power stations in South Africa-External links:...
and Kriel Power Station
Kriel Power Station
Kriel Power Station in Mpumalanga, South Africa, is a coal-fired power plant operated by Eskom. It is located about 4km from Matla Power Station just outside the town of Kriel....
located on the coal fields in the adjacent Olifants River basin.
The dam also provides some flood attenuation for Standerton and stores up to 100 million m3/annum pumped into the upper reaches of the Vaal River basin from Heyshope Dam
Heyshope Dam
Heyshope Dam is a dam on the Assegaai River, Mpumalanga, South Africa. It was established in 1983.- References :* from the Department of Water Affairs and Forestry...
in the Usutu River basin.
During the serious drought of 1983, the water resources in the adjacent Komati River
Komati River
The Komati River is a river in South Africa, Swaziland and Mozambique. It is long, with a drainage basin in size. Its mean annual discharge is 111 m³/s at its mouth...
and Usutu River basins were badly depleted, leading to serious concerns that the water supplies to various power stations could be affected. Any water shortages to the power stations would be disastrous for South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
since 80% of the country's electricity is dependent on water from the Komati-Usutu-Vaal system. It was estimated that the newly completed (1982) Grootdraai Dam would empty within a matter of months and an emergency scheme was therefore initiated to pump water upstream over a distance of 202 km to Grootdraai Dam from Vaal Dam
Vaal dam
The Vaal Dam in South Africa was constructed in 1938 and lies 77 km south of OR Tambo International Airport Formerly Jan Smuts Airport, then renamed Johannesburg International Airport in 1994, before being renamed yet again on 27th October 2006 as ORT. The lake behind the dam wall has a...
. The emergency scheme involved constructing 7 weirs, each with numerous pumps capable of pumping a total of 1 million m3/day. Although the emergency scheme was never used, it was completed and received an award for the Most Outstanding Civil Engineering Achievement of 1983 from the South African Institute of Civil Engineers.