Swakop
Swakop | ||
River bed of the Swakop in the lunar landscape , near Gut Richthofen |
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Data | ||
location | Namibia | |
River system | Swakop | |
source | Mountains of Eros | |
Source height | 1560 m | |
Swakop estuary |
South Atlantic , south of Swakopmund Coordinates: 22 ° 41 ′ 20 ″ S , 14 ° 31 ′ 30 ″ E 22 ° 41 ′ 20 ″ S , 14 ° 31 ′ 30 ″ E |
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Mouth height | 0 m | |
Height difference | 1560 m | |
Bottom slope | approx. 4.5 ‰ | |
length | approx. 350 km | |
Catchment area | 21,010.149 km² | |
Left tributaries | Omusema , Khan | |
Reservoirs flowed through | Omatako Reservoir , Swakoppforte Reservoir | |
Communities | Otjimbingwe , Swakopmund |
The Swakop together with its tributary Khan one of the largest temporary water-bearing rivers dry ( Riviere ) in the west of Namibia . It is 460 km long and has a 21,010.149 km² catchment area . At Swakopmund it flows into the South Atlantic . The name comes from the language of the Nama and Damara , Khoekhoegowab : Tsoa-xaub . Tsoa means excrement opening or anus , while xaub stands for the excrement given off. This name is explained by the observation that when it rains the river carries large amounts of brownish mud with it and releases it into the Atlantic Ocean.
Hydrology
The Swakop drains a 30,100 km² catchment area that stretches from the confluence with the Atlantic Ocean at Swakopmund via Otjimbingwe to around 50 km east of Okahandja and south into the Khomas highlands beyond Windhoek . The highest point of the catchment area is at 2480 m. The annual precipitation varies from 0 mm in the lower reaches to 475 mm in the area of the eastern Khomas highlands. 39% of the catchment area experiences precipitation greater than 300 mm per year and a full 80% of the catchment area experiences annual precipitation over 100 mm.
The Von Bach Dam near Okahandja and the Swakoppforte Dam west of Groß Barmen in the upper reaches of the Swakop are of outstanding importance for the water supply in central Namibia . Like all rivers, the Swakop has a number of important springs and larger wetlands in the lower reaches . Existing groundwater often leads to soil salinization there .
Again and again, stronger floods occur in the lower reaches, the cause of which lies in the gallery forest , which is being pushed back by land use . This contributes to increased and faster runoff and increased erosion of the Swakop alluvial land.
Vegetation and fauna
Due to its size and extent, the Swakop has a very varied catchment area. 29% of the area is in the high-field savannah , 28% is thorn -bush savannah , 34% is semi-desert and savanna transition zone and 9% is in the central Namib . In the highlands there is more or less dense bush vegetation. In the arid lower reaches, stronger vegetation is limited to the direct Swakoptal with the typical gallery vegetation of ana trees ( Faidherbia albida ), tamarisk ( Tamarix ), camel thorn ( Acacia erioloba ), salvadora , various fig species , euclea but also tobacco ( Nicotiana spp. ), Thorn apple ( Datura ) and Mesquite ( Prosopis spp. ) As invasive species .
In the Swakop area, game occurs practically only in the sparsely populated lower reaches and is limited to antelopes , smaller predators and birds. Big game like elephants , rhinoceros as well as lions and other big cats are no longer to be found today. In the rest of the catchment area, however, there are a number of guest and game farms that also offer a home for big cats.
Use and settlement
In contrast to the other dry rivers in the west of Namibia, there are larger settlements in the Swakops catchment area, such as the cities of Usakos , Karibib , Otjimbingwe , Okahandja and the capital of Namibia, Windhoek , so that the population in the catchment area is over 200,000.
While extensive pasture farming is practiced on the farms far from the river in the upper reaches , the dams and the high groundwater level along the entire Swakoptal also allow more intensive agriculture and even vegetable cultivation, for example the cultivation of Swakopmund asparagus near Goanikontes . The high level of groundwater abstraction in agriculture and the high water consumption in cities are causing the groundwater level to fall increasingly . Particularly in the lower reaches, this leads to the drying up of numerous springs and to the death of the gallery vegetation. Due to the agricultural use, the erosion is greatly increased, so that more and more valuable soil is lost and the flood intensity of the Swakop increases.
The uranium mines " Langer Heinrich " in the lower reaches of the Swakop and Rössing am Khan not only contribute to the further lowering of the groundwater level with their high water consumption, it is also repeatedly claimed that radioactive dust reaches the Swakop via the Khan and the vegetables grown there contaminated.
A well-known structure is the Swakop Bridge .
gallery
The mouth of the Swakop in the Atlantic Ocean (2017). In the foreground the pillars of the old railway line
literature
- Hartmut O. Fahrbach: The Swakoptal. Important places on the Swakoprivier, from Langen-Heinrich-Berg to the mouth. Scientific Society Swakopmund, Swakopmund 2011, ISBN 978-99945-73-09-7 .
- Florian Winkler: Groundwater Model of the Swakop River Basin, Namibia. Albert-Ludwigs University of Freiburg, Freiburg 2001.
- Klaus Hüser, Helga Besler, Wolf Dieter Blümel, Klaus Heine, Hartmut Leser, Uwe Rust : Namibia - A Landscape Studies in Pictures . Klaus Hess, Göttingen / Windhoek 2001, ISBN 978-3-933117-14-4 .
- Mary Seely, Kathryn M. Jacobson, Peter J. Jacobson: Ephemeral Rivers and Their Catchments - Sustaining People and Development in Western Namibia . Desert Research Foundation of Namibia, 1995, ISBN 978-99916-709-4-2 .
Web links
Individual evidence
- ↑ Mapping the Major Cathments of Namibia. Ben Ben J. Strohbach, National Botanical Research Institute, pp. 5-6.