Knellpoort Dam
Encyclopedia
Knellpoort Dam is a dam on the Riet Spruit, near Wepener
, Free State
, South Africa
. It was established in 1988.
Due to siltation, the storage capacity of the Welbedacht Dam
reduced rapidly from the original 115 million m3 to approximately 16 million m3 during the twenty years since completion. This reduction in storage created problems in meeting the Bloemfontein demand at an acceptable level of reliability and as a result, the 50 m high Knellpoort Dam was completed in 1988. It was the first arch gravity Roller Compacted Concrete (RCC) dam in the world and comprises almost 64 600 m3 rollcrete and 14 200 m3 concrete with a gross storage capacity of 137 million m3.
In order to prevent similar siltation problems to those experienced at the Welbedacht Dam
, the Knellpoort Dam functions as an off-channel storage dam with a relatively small catchment area of only 798 km2 and corresponding MAR of approximately 20 million m3/a . Water from the Caledon River
is pumped to Knellpoort Dam from the Tienfontein Pumping Station via a 2 km long canal which is equipped with a silt trap to reduce siltation in the main reservoir.
Wepener
Wepener is a village in the Free State, South Africa, located on the border with Lesotho. The town is named after Louw Wepener, the leader of the Boers in their war with the Basotho chief Moshoeshoe I in 1865. It was founded in 1867 on the banks of Jammersbergspruit, a tributary of the Caledon...
, Free State
Free State
The Free State is a province of South Africa. Its capital is Bloemfontein, which is also South Africa's judicial capital. Its historical origins lie in the Orange Free State Boer republic and later Orange Free State Province. The current borders of the province date from 1994 when the Bantustans...
, 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 1988.
Due to siltation, the storage capacity of the Welbedacht Dam
Welbedacht Dam
Welbedacht Dam is situated in South Africa, and was established in 1973.Bloemfontein is the sixth largest city in South Africa with a population of approximately 300 000. It is situated in the Modder River catchment which has insufficient water resources to meet the growing water requirements...
reduced rapidly from the original 115 million m3 to approximately 16 million m3 during the twenty years since completion. This reduction in storage created problems in meeting the Bloemfontein demand at an acceptable level of reliability and as a result, the 50 m high Knellpoort Dam was completed in 1988. It was the first arch gravity Roller Compacted Concrete (RCC) dam in the world and comprises almost 64 600 m3 rollcrete and 14 200 m3 concrete with a gross storage capacity of 137 million m3.
In order to prevent similar siltation problems to those experienced at the Welbedacht Dam
Welbedacht Dam
Welbedacht Dam is situated in South Africa, and was established in 1973.Bloemfontein is the sixth largest city in South Africa with a population of approximately 300 000. It is situated in the Modder River catchment which has insufficient water resources to meet the growing water requirements...
, the Knellpoort Dam functions as an off-channel storage dam with a relatively small catchment area of only 798 km2 and corresponding MAR of approximately 20 million m3/a . Water from the Caledon River
Caledon River
The Caledon River is located in south-east Africa, rising in the Drakensberg Mountains in Lesotho. Origin in the former bantustan of QwaQwa, near the border with Lesotho, southwest of Witsieshoek. It then flows south-west, marking the border with South Africa and Lesotho before entering South...
is pumped to Knellpoort Dam from the Tienfontein Pumping Station via a 2 km long canal which is equipped with a silt trap to reduce siltation in the main reservoir.
See also
- Welbedacht DamWelbedacht DamWelbedacht Dam is situated in South Africa, and was established in 1973.Bloemfontein is the sixth largest city in South Africa with a population of approximately 300 000. It is situated in the Modder River catchment which has insufficient water resources to meet the growing water requirements...
- List of reservoirs and dams in South Africa
- List of rivers of South Africa