Orange River

The Orange River (Afrikaans: Oranjerivier; English: Orange River) is the second most important river in southern Africa after the Zambezi River and the most important in the republic of South Africa. It flows west from its source in the Drakensberg Mountains, Lesotho, to its mouth in the Atlantic Ocean near the town of Alexander Bay, halfway between Walvis Bay and Cape Town. It has a route of 2200 km and in its final section it forms the border between South Africa and Namibia.

Its main tributary is the Vaal River, which also rises in the Drakensberg mountain range, east of Johannesburg and forms the border between the Transvaal and the Free State, before joining the Orange southwest of the Kimberley. After joining the Vaal, the Orange runs through the arid and wild terrain of the southern Kalahari and Namaqualand region.

During the last 800 km of its course it receives many intermittent streams and several wadis. The flow volume is considerably reduced due to evaporation. In the rainy season, the Orange becomes a rushing torrent.

The river was discovered by Europeans in 1760 and was named after the House of Orange of the Netherlands around 1777-79.

History

Etymology

Some early pre-colonial inhabitants called the river ǂNūǃarib, referring to its black color, or sometimes simply Kai !Arib ("Great River"), from which the Afrikaans version Gariep is derived, and the translation "Groote Rivier". The first Dutch name for the river was just that translation, Groote Rivier, meaning 'Great River'. The river was named the Orange River by Colonel Robert Gordon, commander of the United East India Company (VOC) garrison at Cape Town, on a voyage into the interior in 1779. Gordon named the river after William V. Orange-Nassau. A popular but incorrect belief is that the river received its name from the supposedly orange color of its water, as opposed to the color of its tributary, the Vaal River, derived from the name ǀHaiǃarib "pale river" (vaal means pale or gray in Afrikaans). Since the end of apartheid, the name "Gariep" has had greater favor in official correspondence in South Africa, although the name "Orange" It has greater international recognition. In Lesotho, where the river originates, it is known as the Senqu River, derived from the original name Khoemana.

Change of the name of the river

The Eastern Cape Geographical Names Committee has announced its intention to consider a renaming of the colonial name, for that part of the river that forms the border between the Eastern Cape and the Free State, with suggestions such as IGqili or Senqu. The advertisement placed in the Aliwal Weekblad newspaper states that "the current name is perceived to have a strong association with the history of colonial subjugation and therefore has no place in the current democratic situation.".

The Grootslang

In South African folklore, the Orange River is often associated with the Grootslang, a mythical being resembling a giant snake, which is often associated with the river's alluvial diamonds. The Grootslang is said to live in a gem-filled cave connected to the Orange River by a natural pipe through which the diamonds gradually enter the river. Other places where the creature is said to hide are the pond under the waterfall. of King George at Aughrabies Falls, which is also said to be a fountain of diamonds, and a large rock in the middle of the river itself. In this version of the legend, the Grootslang is also said to prey on livestock on the river banks.

Course

The Orange rises in the Drakensberg Mountains, along the border between South Africa and Lesotho, about 193 km (119.9 mi) west of the Indian Ocean and at an altitude of more than 3000 m s. n. m. (meters above sea level). The end of the Orange River within Lesotho is known as the Senqu. Some parts of the Senqu River freeze in winter due to its high altitude. This causes droughts downstream, which mainly affect goat and livestock production.

The Orange River then flows west through South Africa, forming the southwestern boundary of the Free State province. In this section, the river flows first into the Gariep dam (the largest in the country), and later into the Vanderkloof dam. From the border with Lesotho to below the Vanderkloof Dam, the riverbed is deeply incisive. Further down, the land is flatter and the river is widely used for irrigation.

At the western point of the Free State, south-west of Kimberley, the Orange joins its main tributary, the Vaal River, which in turn forms much of the province's northern border. From here the river flows westwards through the arid wilderness of the southern Kalahari region and Namaqualand in the Northern Cape Province to meet Namibia at 20° E longitude. From here it flows westwards for 550 km, forming the international border between the province and the Karas region of Namibia. At the border, the river passes through the town of Vioolsdrif, the main border post between South Africa and Namibia.

In the last 800 km (497.1 mi) of its course, the Orange receives many intermittent streams, and several large wadi flow into it. In this section, the Namib Desert ends at the north bank of the river, so under normal circumstances the volume of water added by these tributaries is negligible. Here, the river bed is again deeply incised. Augrabies Falls is located on this stretch of the Orange, where the river drops 122 m (400 ft) over a course of 26 km (16.2 mi).

The Orange flows into the Atlantic Ocean between the small towns of Oranjemund (meaning 'mouth of the Orange') in Namibia and Alexander Bay in South Africa, equidistant between Walvis Bay and Cape Town. About 33 km from its mouth, it is obstructed by rapids and sandbanks and is not navigable in most of its sections.

Fall and precipitation

In the dry season, the river's water volume is greatly reduced due to rapid runoff and evaporation. At the headwaters of the Orange, rainfall is about 2 mm (0.1 in) annually, but rainfall decreases as the river flows westward; at its mouth, rainfall is less than 50 mm (2 in) annually. However, the factors that favor evaporation tend to increase towards the west. In the wet season (summer), the Orange River turns into a brown torrent. The enormous mass of sediment washed away constitutes a long-term threat to engineering projects in the river.

The total Orange River basin (including the Vaal) extends over 973 km² (375.7 mi²), equivalent to approximately 77% of the land area of South Africa (1,221,037 km^{2< /sup>). About 366 km² (141.3 mi²) (38%), however, are located outside the country, in Lesotho, Botswana and Namibia.}

Taxes

• River Vaal - 1.458 kilometers (0.9 mi)
• Rio Caledon - 642 kilometers (398.9 mi)
• Khubelu River - 144 kilometers (89.5 mi)

Dams

• Dam of Armenia
• Egmont Dam
• Gariep Dam
• Newberry Dam
• Vanderkloof Dam
• Welbedacht Dam

Economy

As the collection point for most of South Africa's water, the Orange River plays an important role in supporting agriculture, industry and mining. To help with this, two major water schemes have been created, the Orange River Project and the Lesotho Highlands Water Project. Historically, the river played an important role in South Africa's diamond rush, and the country's first diamonds were discovered in alluvial deposits at Orange. Today, several commercial diamond mines operate along the final stretch of the Orange River and around its mouth. Additionally, due to the lack of dangerous animals and high water levels during the summer, the river is used for recreational boating and rafting. Rafting on the Orange River has become very popular with many companies using their campgrounds along the river from which they operate. The most popular trips are the four- and six-day river trips along the gorge below Augrabies Falls or along the Richtersveld area.

Orange River Project

The Orange River Project (ORP) was one of the largest and most imaginative projects of its kind in South Africa. It was built by Hendrik Verwoerd's government at the height of the apartheid era. The ORP was built to utilize unused water from the Orange River, which, without the Vaal River, accounts for around 14.1% of total runoff in South Africa, and in the process, to meet growing water demand. The main objectives of the project were:

• to stabilize the flow of the river,
• the generation and transmission of hydropower,
• to provide a reliable water supply for users in the Orange River basin, and
• to give a new life to areas with water shortages in the Eastern Cape, such as the Great Fish and Sundays River valleys.

The Gariep Dam near Colesberg, formerly called the Hendrik Verwoerd Dam when it was built, is the main storage structure within the Orange River. From here, water is supplied in two directions, westwards along the Orange River (via hydroelectric power generators) to the Vanderkloof Dam, which was previously called PK le Roux Dam, and southwards through the Orange-Fish tunnel to the Eastern Cape.

Hydroelectricity

Eskom operates hydroelectric plants at both the Gariep Dam and the Vanderkloof Dam. The Vanderkloof Dam hydroelectric power station was the first power generation station in South Africa located completely underground. The towns of Oviston and Oranjekrag were established to facilitate the construction and operation of the new infrastructure.

Irrigation

Irrigation in the vast area downstream of the Vanderkloof Dam, which has converted thousands of hectares of arid veld into highly productive agricultural land, was made possible by the construction of the Gariepand Vanderkloof Dams. Older, established irrigation schemes such as Buchuberg, Upington, Kakamas and Vioolsdrif have also benefited because it is now possible to regulate flow. On the Namibian side of the river, Aussenkehr produces grapes with the help of the water of the Orange.

In recent years, the wine-producing areas along the Orange River have grown in importance. Irrigation in the Eastern Cape has also received a tremendous boost, not only due to the availability of additional water, but also due to improvements in water quality. Without this improvement, citrus growers along the Lower Sundays River would likely have continued to suffer productivity losses.

Lesotho Highlands Water Project

The Lesotho Highlands Water Project was conceived to complement the water supply in the Vaal River System. The water is delivered to South Africa via the delivery tunnel which passes under the Lesotho-South Africa border in the Caledon River, and then under the Little Caledon River south of Clarens in the Free State, and empties into the river Ash about 30 km further. To the north the scheme became viable when water demand in Gauteng reached levels that could no longer be economically supported by alternative schemes such as the Tugela River - Vaal River pumped storage scheme, which used the Sterkfontein Dam, located near Harrismith. in the Free State.

Alluvial diamonds

In 1867, the first diamond discovered in South Africa, the Eureka diamond, was found near Hopetown on the Orange River. Two years later, a much larger diamond known as the South African Star was found in the same area, sparking a diamond rush. This was soon eclipsed by the diamond rush to extract diamonds directly from the kimberlite in Kimberley in 1871, although alluvial diamonds continued to be found in Orange. Today, several commercial diamond mines operate on the last stretch of the river, as well as on the beaches around its mouth. Diamond mines also operate in the middle reaches of the river.

Rafting and canoeing

During the mild months of March and April, if it rains well and the dam locks are open, a canoeist (or rafter) can easily travel 30 kilometers (18.6 mi) a day. The lower reaches of the river are the most popular for their spectacular topography. There are commercial excursions that depart from the border town of Vioolsdrif.

Fauna

The Orange River has no large animals. It is located outside the range of the Nile crocodile, and although hippopotami were abundant in the past, they were hunted to extermination in the 19th century . The Orange River has a relative lack of species diversity. A 2011 study of 13,762 fish found only 16 fish species present.^{[citation needed]} Three of them, the common carp, the Mozambique tilapia, and the western mosquitofish they are non-native.^{[citation needed]} Another exotic species, the rainbow trout, is found in the headwaters of the river in Lesotho.

.

Seven species are endemic to the Vaal-Orange river system:

• Fish rock cat (Austroglanis sclateri)
• Maloti redfin or Maloti minnowPseudobarbus quathlambae)
• Barbo de Namaquab (Barbus hospes)
• River sardine (Mesobola brevianalis)
• Yellow fishLabeobarbus aeneus)
• Largemouth yellowfish (Labeobarbus kimberlyensis)
• Fish of Orange River mud (Labeo capensis)