Nelson Mandela Bay Municipality has embarked on a series of drought intervention projects designed to ensure future water security. Two of these are currently being constructed by multidisciplinary contractor Stefanutti Stocks, namely the Nooitgedagt/Coega Low Level Scheme: Phase 3, and the Coegakop Biofiltration Water Treatment Works – the latter in consortium with PCI Africa.
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he Eastern Cape region has experienced arid conditions for decades. More recently, though, the problem has worsened into an extended drought that poses a threat to the regional economy. In response, emergency water master plans have been developed to mitigate and manage immediate and longerterm scenarios. One of the key focal points is Port Elizabeth, the province’s largest city and the administrative capital of Nelson Mandela Bay Municipality (NMBM), which extends to include the towns of Despatch and Uitenhage, the latter being one of South Africa’s major automotive manufacturing hubs. As part of a longer-term response strategy, NMBM appointed Zutari (previously Aurecon South Africa) to develop a Drought Mitigation and Action Plan. The Water Reconciliation Strategy Study for the Algoa Water Supply Area, published in
Biofiltration: A diagrammatic explanation of the process engineering workflow required to remove the iron and manganese concentrations in the groundwater abstracted at the Coegakop wellfield
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IMIESA August 2020
Bulk earthworks in progress at the Coegakop WTW, with the boundary wall and access road already constructed
Tapping the Coegakop wellfield
2008, identified groundwater as a future water supply option. In 2010, the decision was made to fast-track the viability of groundwater as a potential emergency supply option. In the interim, specific initiatives were approved, including the Nooitgedagt/Coega Low Level Scheme. The third and final phase of the scheme is currently being constructed by Stefanutti Stocks for NMBM. Amatola Water was appointed by the Department of Water and Sanitation (DWS) as the implementing agent. The project started in May 2017 and is scheduled for completion in July 2021.
Nooitgedagt Situated just north of Port Elizabeth near the Addo Elephant Park, the Nooitgedagt Water Treatment Works (WTW) Phase 3 work entails the treatment capacity being upgraded from 140 Mℓ/day to 210 Mℓ/day. A 45 Mℓ storage reservoir has also been constructed during this phase to accommodate the extra capacity. Additionally, the scope includes some rehabilitation work and cathodic protection of the existing pipe supply system.
Orange River water is delivered to the plant via the Orange-Fish Scheme (Darlington Dam and canals) to the Scheepersvlakte Dam. From there, it flows by gravity pipeline to the Nooitgedagt WTW. Thereafter, the water is treated then gets pumped to the existing 10 Mℓ reservoir, and the newly constructed 45 Mℓ reservoir.
Prime groundwater targets “Similar to Cape Town’s Day Zero experience, NMBM’s strategy combines the need for greater conservation management with consumer education to lower demand, so we can preserve current resources while developing reserve capacities to meet future drought contingencies and growth projections,” explains project engineer Edzard Verseput, Infrastructure & Engineering: Water & Sanitation, NMBM. Groundwater abstraction is now officially on board and will supplement NMBM’s current consumption of around 300 Mℓ/day. Like Cape Town, the greater Port Elizabeth area is underlain by Table Mountain sandstone containing extensive artesian aquifers. In
