All of South Africa’s biggest dams have been developed with the help of cement mixers and concrete. This article considers how some of South Africa’s biggest dams have been produced with the help of this strong, durable and water material.
The Importance Of Dams
Without dams, the accessibility of clean water would be severely limited, making it difficult for humans to get the resources they need to go about their daily lives. Dams indirectly impact the amount of water we drink, the capacity of our taps and basins, our irrigation systems, the health of the food chain and the quality of ablutions and functionality of waterways throughout cities.
Although many of us probably know little about their development, maintenance and significance, it is safe to say that South Africa’s biggest dams — built with the help of cement mixers, manual labourers, architects and city planners — are the backbone of our water infrastructure. What’s more, dams also offer a solution to flood control, regulating the flow of water during heavy rainfall and ensuring that such resources are not wasted. Without dams, it is a lot more likely that flooding would occur in areas with heavy rainfall or a lack of wetland, causing a major threat to nearby communities and their infrastructure.
Dams also generate money through tourism, all of which contribute to the gross domestic product and the availability of funding for public services. Boating, swimming, fishing and other forms of eco-tourism are incredibly popular in dams throughout South Africa and the rest of the world. These major bodies of water are often a site for sore eyes and encourage guests from all over the country to visit and enjoy.
Finally, another vital point of interest when it comes to dams is their ability to generate massive amounts of electricity through hydroelectric power generation mechanisms, reducing reliance on traditional fossil fuels such as gas and coal.
The Importance Of Dams In South Africa
Dams are particularly important in South Africa because certain regions are known to experience drought throughout drier seasons. With a semi-arid climate, certain regions are likely to experience long bouts of minimal rainfall, which ultimately affects the availability of drinking water as well as water necessary for farming and industrial operations. For example, in Cape Town dams and their maintenance and monitoring are absolutely mandatory, especially following the water crisis suffered between 2015 and 2018.
Other areas affected by drought include semi-desert regions like the Kalahari in the Northern Cape and the nearby Namaqualand, the Karoo regions and Nelson Mandela Bay in the Eastern Cape, Bloemfontein in the Free State and other areas such as Polokwane and Thabazimbi in Limpopo and the Northwest Province. When these areas are experiencing water shortages as a result of low rainfall and hot, dry conditions, the consequences can be severe.
Lack of water for irrigation can lead to poor crop yields, below-average food production, and consequent food shortages. Rural communities that rely on income from agriculture will be hard hit, and the remainder of the population will equally feel the effects of lesser access to food and water. What’s more, interruptions in water supply can have a major impact on industry.
Beyond agriculture activities such as maize, wheat and citrus farming — all of which require ample access to water — other sectors of the economy can quickly become bankrupt should their water access be limited. For example, mining, manufacturing, tourism, hospitality, construction and industrial processing for chemicals, textiles and beverages all rely heavily on adequate water provisions. What’s more, the quality of living is expected to dip heavily with struggling industries, reduced food production and a lack of clean drinking water or ablutions. Water is an essential resource that has an influence on every aspect of our daily lives, which is why it is so important to provision and plan supply.
For all of the above reasons, access to water is vital in South Africa and throughout nations across the world. This is why it is so important that city planning adequately accounts for the provision of water to nearby areas through the development and maintenance of large dams. Damns support economic growth and offer a reliable source of water in case of natural emergencies and drought scares.
Dams are just part of an overarching public management system that ensures that valuable resources are protected and administered effectively. Without such infrastructure, the country’s resilience in the face of water security crises and progressively worsening climate change conditions is at risk.
Use Of Cement In South African Dams
Cement plays an important role in the construction and durability of South African dams, which are consistently under extreme hydrostatic pressure due to the immense weight of stored water and fluctuating water levels. With such pressures in mind, it is essential that only the most durable, reliable and hardy materials are used to fashion dams that should, ideally, last decades. Cement mixers are indispensable in their capacity to mix and produce large volumes of concrete which can be used in dam construction.
Cement mixers ensure that the concrete supply remains uninterrupted and that consistency is uniform throughout, ensuring maximum strength. The portability of mixers is also an added advantage when building dams, as it allows for easy transportation of equipment to remote locations, where dams are usually fashioned. With the highest quality mixers on site, the construction team do not have to be concerned about extending timelines as a result of supply issues, making them ideal for large-scale projects with tight timelines.
Cement usage in dam construction is particularly valuable because cement has greater load-bearing capacity than most alternatives, providing the ability to handle excessive hydrostatic pressure and consistent weight. What’s more, cement’s resistance to erosion ensures that the dam’s strength can be maintained for a number of years and that its structural integrity will not be compromised by weathering, turbulence or water flow.
The primary application for cement is on the dam walls, reservoir linings, spillways and overflow structures. Cement is the core component of the overall structure, with great ability to prevent seepage and reinforce the enormous size of the dam. Hydraulic cement is also used to seal any fault lines or cracks when damage occurs, as it hardens quickly, prevents further leaking and is able to hold even when submerged or in contact with water.
Hydraulic cement requires short working time and seamless application and can equally be mixed with cement mixers when necessary, ensuring a tight seal thanks to its expansive qualities. Clearly, cement’s water resistance, durability, ease of use and accessibility makes it the perfect option for such large scale projects. It can also be used in many other alternative contexts, such as when working with bridges, buildings and other kinds of foundational structures.
Popular South African Dams
Throughout South Africa, the biggest dams are known to have used concrete and cement mixers extensively. Thanks to South African cement companies such as Sephaku, Dangote, PPC, AfriSam, Afrimat, Lafarge and Natal Portland Cement Company (pty), Ltd., local construction companies have not had to worry about accessing the correct materials for dam development and construction. Instead, builders can safely and quickly acquire high-quality aggregates, fly ash and concrete from local suppliers.
Trust in the quality of primary materials is particularly important in the South African context because engineering and design plans have to be adapted to local conditions. The geographic placement of the dam, its scale, complexity, sedimentary movements and surrounding earth will require specific accommodations to ensure maximum safety. South Africa has problems such as rapid sedimentation due to soil erosion, undulating terrain and harsh weather conditions, making it particularly challenging to build on.
Yet, South African engineers and city planners have innovated solutions that overcome the specificities and challenges of the local context. The country has seven massive concrete dams — of which the four biggest are described below — each with slightly different cement mixer usage, make and modelling. These dams have to be carefully designed around local conservation sites, considering any effects on local wildlife, habitat and tourism plans.
The development of such massive infrastructural feats requires years of planning, massive public spending and the alignment of various transversal policies across various departments. And even once they are built — with the assistance of multiple stakeholders and suppliers, cement mixers and other resources — there is still the ongoing work of repair, monitoring and oversight. Without such control and management, these dams would struggle to sustain the growing population and ever-increasing demands for water.
Gariep And Vanderkloof Dam
Located in the Free State on the Orange River, this dam is by far the biggest in South Africa, with a whopping 5.340 million cubic meter storage capacity. This dam is connected to the Gariep Reservoir and is closely connected to the Vanderkloof dam, which also forms part of the Orange River Project despite being in the Northern Cape. Both the Gariep and Vanderkloof dams are responsible for regulating the flow of the Ricer’s supply and are surrounded by a number of other smaller but still very important canal projects.
Vanderkloof is slightly smaller at 3,171 million cubic meters. However, it is popularly known for its incredibly high walls of 108 meters. Both dams are sources of irrigation water, yet Gariep Dam can generate major hydroelectric power while Vanderkloof’s power generation is only a secondary capability. Interestingly, this dam used large volumes of concrete in its arch-gravity wall design and relies heavily on concrete for its spillways and supporting structures.
Sterkfontein and Vaal Dam
The Vaal Dam is 2.613 million cubic meters and works hand in hand with the Sterkfontein Dam, supplying directly to Gauteng’s industrial areas and residential homes, acting as the key provider for South Africa’s biggest city. Meanwhile, responsible for providing backup water to cities throughout Gauteng should the Vaal dam run short, Sterkfontein is the official reserve for the Vaal River system.
Much smaller than Gariep or Vanderkloof dam, Sterkfontein is an off-channel dam with a capacity of 2.616 Million found in the Free State. While the Sterkfontein is an earth-fill dam, the Vaal Dam is predominantly composed of mass concrete and consequently requires ample access to both aggregates and equipment.
Dam Construction And BS Power
Whether you’re a contractor or project manager looking to purchase a cement mixer that can be put to use either on an existing dam or in the development of a new water storage facility, BS Power can certainly provide the equipment necessary to do the job effectively and affordably. On such large-scale projects where the risks are significant and the engineering factors are complex, it is vital that the equipment used is of the absolute best quality and is adequately able to ensure a structurally sound outcome.
Cement mixers, much like cement, are a cornerstone and foundational element influencing the supply and management of South African water. Consequently, it is BS Power’s promise to provide only the best possible goods for your construction needs, so visit our website today to learn about what we can offer you.