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THE – South ’s water workhorse

Major dams and weirs The Vaal River is often described as the hard- on the Vaal River est working river in . But what does • this mean? And why is this river so important to the country? • Dam • Lani Lani Vuuren van Vaalharts Weir • Douglas Weir he Vaal River (named after its ensure a steady water supply to all those naturally dull brown-grey col- people and industries dependent on water our) is the second-largest river from the river. activities, such as boating, in South Africa, after the Orange In earlier times, many little dams were skiing, , swimming and many holi- River, into which it flows. The built to irrigate farms. These dams were day resorts have grown up on its banks. 1 200T km-long river crosses a number of the forerunners of the great barrages and The biggest dam on the Vaal River is provinces, namely , the , dams which today control the river on the Vaal Dam. This dam was built in 1938. and the . which Gauteng and the surrounding indus- While it was the biggest dam to be built in The Vaal River starts in the eastern trial areas depend so heavily. One of the South Africa at the time, it was constructed plains, in the vicinity of Ermelo, first large schemes to be built on the Vaal almost entirely by hand by hundreds of in Mpumalanga. The river then flows River was the Vaal Barrage. This dam, workers. These workers lived and worked westward on a long course, without rapids situated about 70 km from at the dam in special construction villages, or waterfalls, broadening into a large river. was finished in 1923. This dam has a which had everything from housing, to While it is a major river it is still a tributary capacity of 63 million litres. canteens to an entertainment complex. as it does not reach the sea, but instead The Suikerbosrant, Klip, and Rietspruit The Vaal Dam has been raised twice. joins the at Douglas, in the rivers that feed into the Vaal River Barrage In the early 1950s the wall was raised by Northern Cape. Reservoir flow from industrial and heav- 6.1 m enabling it to store 2 188 million m3. The Vaal River might not be large by ily populated areas such as Johannesburg, Then it was raised again in 1985 by another international standards (it is about the and . This reservoir 3.5 m. This increased the volume of the 129th largest river in the world) it is large was used to supply water to the Witwaters­ dam to 2 575 million m3. The dam has a by South African standards. Yet it does not rand but no longer does so because the surface area of 321 km2 and an average run constantly, which means that in winter quality of its water is deteriorating due depth of 22.5 m. it has much less water than it has in the to pollution, says . However, According to Rand Water, the main rainy season. For this reason large dams this reservoir, which is managed by Rand water supplier to Gauteng, even though the have had to be constructed on the river to Water, is still used for many recreational Vaal Dam is only the fourth-largest dam

44 The Water Wheel July/August 2014 in South Africa today, it is still the most important dam in the country because of its role as the primary supplier of water to the economic heartland of South Africa. The water from the Vaal River supplies water to all of the most important industries in South Africa situated around and Johannesburg. These industrial areas produce more than 50% of South Africa’s wealth as well as more than 80% of the country’s electricity requirements – more than 50% of all the electricity supplied in South Africa. From the Vaal River water is also supplied to some of the largest and platinum mines in the world, as well as many of the world’s largest coal reserves. Further down the Vaal Dam and Vaal

Barrage there is the . www.eoearth.org This dam has a surface area of 232 km2. At Christiana there is a complex series Even these dams have not been enough Above: Map showing the Vaal River. of canals which takes the water to about to supply the increasing need for water. Below: The Vaal Barrage. 1 200 farms in one of the largest irriga- Water now gets ‘imported’ from KwaZulu- tion schemes in the southern Hemisphere. Natal to the Vaal Dam from the Thukela- This is the Vaalharts Scheme. At Vaal Transfer Scheme and as far as Douglas, in the Northern Cape, the Vaal from the Lesotho Highlands Development River meets the Orange River. The Orange Project. River, which has its origin in Lesotho, then The Vaal River is not only the hardest continues westward and eventually flows working river in South Africa because of into the Atlantic Ocean at Alexander Bay. all the people and industries it supports, it also has to deal with a lot of pollution, like Did wastewater treatment plants, runoff from mines, industries and agriculture. Organi- you know? sations like Rand Water and Save the Vaal Environment work to improve conditions The Vaal River get its name Lani Vuuren van in the catchment of the Vaal River and from the muddy colour of its so improve the quality of water that water, with ‘Vaal’ meaning ‘grey Sources enters the river.  water’. The name is translated from the Khoikhoi name of - • www.southafrica.net/za/en/ the river, which is articles/entry/article-southaf Heigariep. rica.net-vaal-river • http://www.randwater.co.za/ corporateresponsibility/wwe/ pages/waterorigination.aspx - • http://www.ewisa.co.za/misc/ RiverVaal/VAALRiver_Geol ogy%20.htm • https://www.youtube.com/ watch?v=IgHYsa-D8tk&list=P LOz2OX6evpWMZyKDK3s7Y (a video from tHEVSd5VQ9K0 newspaper of The Citizen the Vaal Dam with its sluices open) Many people enjoy the Vaal Dam from • http://www.eoearth.org/view/ a recreational point of view. article/228145/ Lani Lani Vuuren van

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