The Bokaa Dam is a dam on the

Metsimotlhabe River The Metsimotlhabe River is the largest river in the Kweneng District of Botswana, draining the area that lies to the south of Molepolole into the Notwane River, in turn a tributary of the Limpopo River. The name "Metsimotlhabe" means "water sand ...

, a tributary of the

Ngotwane River The Notwane River (or Ngotwane River) is a river in southeastern Botswana. Certain sections of its course form the international boundary with South Africa. Its mouth is at the head of the Limpopo River. It has a catchment area of 18,053 square k ...

, in

Botswana Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label=Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalahar ...

. It provides water to the capital city of

Gaborone Gaborone ( , , ) is the capital and largest city of Botswana with a population of 246,325 based on the 2022 census, about 10% of the total population of Botswana. Its agglomeration is home to 421,907 inhabitants at the 2011 census. Gaboron ...

. It is operated by the

Water Utilities Corporation Water Utilities Corporation (WUC) is a government-owned corporation that provides water and waste water management services in Botswana. The Board is appointed by the Minister of Minerals, Energy and Water Resources. The water supply is critica ...

Structure

The Bokaa Dam was built in 1990/1991 by damming the

, a tributary of the

Ngotwane river The Notwane River (or Ngotwane River) is a river in southeastern Botswana. Certain sections of its course form the international boundary with South Africa. Its mouth is at the head of the Limpopo River. It has a catchment area of 18,053 square k ...

just south of

Bokaa Bokaa is a village in Kgatleng District of Botswana. The village is located around 20 km south-west of Mochudi Mochudi is one of the larger villages in Botswana with a population of 44,815 people in 2011. It is situated in the Bakgatla ...

village. The catchment area is about . The dam is an earthcore fill structure with a crest level height of . It was opened in 1993. The dam's surface area when full is . The reservoir is about in length and over at its widest.

Water supply

The Bokaa Dam has a capacity of . It is about from Botswana's capital of Gaborone. As of 2012 the dam provided 25% of the water supply for Gaborone and surrounding areas. There were exceptionally dry conditions in the winter of 2012, and the reservoir dried up and was closed in September 2012. The

North-South Carrier The North-South Carrier (NSC) is a pipeline in Botswana that carries raw water south for a distance of to the capital city of Gaborone. Phase 1 was completed in 2000. Phase 2 of the NSC, under construction, will duplicate the pipeline to carry ...

(NSC) pipeline came into service in 2000, delivering water to Gaborone from the north and running past the Bokaa Dam. An early version of the NSC plan used the Bokaa Dam as the reservoir, but it was decided to instead build a covered reservoir closer to Gaborone at

Mmamashia Mmamashia is a location in Botswana about north of the capital city of Gaborone that is the site of the Mmamashia water treatment plant and master balancing reservoir. Waterworks The reservoir and plant are operated and maintained by the Water ...

to minimise loss of water through evaporation. Water from the Bokaa Dam is now injected into the NSC pipeline. Water is treated at the Mmamashia plant, directly to the south.

Reservoir uses

There is a picnic spot for weekend visitors on the southern shore. The dam is in a region of

Acacia ''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...

savanna A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to ...

that is used for grazing many livestock including sheep, goats, donkeys and cattle. The fence is in disrepair so the livestock have trampled the water edge into bare mud in many areas. The reservoir is home to many water birds, notably an important population of

southern pochard The southern pochard (''Netta erythrophthalma'') is a species of duck, and a member of the genus ''Netta''. There are two subspecies, the South American (southern) pochard ''N. e. erythrophthalma'' (Wied-Neuwied, 1833) and the African (southern) p ...

. Significant numbers of

great crested grebe The great crested grebe (''Podiceps cristatus'') is a member of the grebe family of water birds noted for its elaborate mating display. Taxonomy The great crested grebe was formally described by the Swedish naturalist Carl Linnaeus in 1758 in t ...

have also been observed. Sometimes it is home to small numbers of

pink-backed pelican The pink-backed pelican (''Pelecanus rufescens'') is a bird of the pelican family. It is a resident breeder in the swamps and shallow lakes of Africa and southern Arabia; it has also apparently extirpated in Madagascar. Taxonomy The pink-backe ...

. Between 1991 and 1995, counts of waterfowls peaked at about 4,000 individuals.

References

Citations Sources * * * * * * * * {{Dams and reservoirs in Botswana Reservoirs and dams in Botswana Dams completed in 1993 Earth-filled dams Kgatleng District Dams in Botswana