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supply capacity, Station 5A improves Rand Water’s network resilience and Gauteng’s water security,” explains Sipho Mosai, Sipho Mosai, chief executive, chief executive, Rand Water. Rand Water As one of the oldest pump stations within the Rand Water distribution network, Zuikerbosch follows a zero Zuikerbosch effluent discharge process. Station 5A is This is an engineering approach to water a water purification treatment where all plant under construction, water is recovered; the located within the Rand Water process water is recycled Zuikerbosch Water Treatment Plant back to the intake works of the plant and in Vereeniging. By Kirsten Kelly the contaminants are reduced to solid waste at the water residue disposal site. cheduled for completion A three-phase commissioning in 2024, the R3.9 billion strategy has been adopted for project will purify an the project. The first phase will be additional 600 Mℓ/day, completed in the last quarter of 2022, which will augment the Zuikerbosch where 150 Mℓ/day of water will be water supply capacity to the Palmiet available to the overall water supply and Mapleton booster stations. These capacity of Zuikerbosch. A pipeline booster stations (50 km from Station 5A) will be connected between the filter feed the greater eastern and northern house of Station 5A and ‘System 3’, parts of the Gauteng province. The which will give the station flexibility new capacity of Station 5A also offers in operating and maintaining the refurbishment opportunities for older existing operational plants with potable infrastructure at Rand Water’s minimal disruptions. Zuikerbosch Water Treatment Plant. The construction of the R3.9 billion “High water demand and inefficient project was split into subcontracts, water systems in Gauteng remain a the following of which have either concern in a country that receives reached practical completion or are approximately half the global average within their respective stages of of rainfall. By increasing Rand Water’s plant commissioning:
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• raw water pipeline from the Zuikerbosch station forebay/buffer dam and all other secondary pipeline works • lime slaking and dosing plant, and lime loading bay • polyelectrolyte dosing plant • activated silica dosing plant • flocculation, sedimentation and sludge pump plant • medium-voltage power supply and reticulation of Station 5A and all the associated infrastructure. The following contracts are either under construction or still need to be procured: • filter house plant (design and construction phase) • reservoir and engine room (design and construction phase) • disinfection plant (scoping phase) • landscaping and permanent roads (scoping phase). Spiral flocculators and chemical dosing plants Raw water is pumped from the Zuikerbosch forebay/buffer dam all the way to the intake system. The pipeline then gravity-feeds water from the intake tank. All raw water contains suspended particles that must be removed. Water from the Vaal Dam contains highly dispersed particles that tend to remain suspended for a very long period because they are colloidal. Chemical coagulants, such as calcium hydroxide (slaked lime), are used as an aid to settle these particles. This calcium hydroxide
