HDPE lined pipes were installed to protect the infrastructure from attack against biogenic corrosion
Driftsands sewer project to unlock further development Commencing in the western suburbs and terminating at the Driftsands Wastewater Treatment Works (WWTW), the Driftsands Collector Sewer Project is a critical component of the city’s expansion plan to serve the growing western suburbs, and the economic nodes developing alongside the N2, Fairview and Walmer.
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ccording to Melanie Geyer, project manager: Planning and Research Division, Nelson Mandela Bay Municipality (NMBM), the existing Driftsands sewer line – which is 12.5 km long – was constructed in 1983 and commissioned in 1986. “Numerous new developments have been built since 1986. The pipeline has reached its design limitations and must therefore be augmented to allow all wastewater to drain to the Driftsands WWTW. There are two other collector sewer lines in the western suburbs – Lorraine/Fairview and Walmer Heights – that discharge wastewater into the Driftsands Collector Sewer at different points. Therefore, any upgrades or augmentation to those two collector sewer lines, prior to increasing the
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capacity of the Driftsands Collector Sewer, would be pointless.” The project has a significant economic impact on the municipal environment because any future developments in the area (such as the Baywest Development on the N2) may not be approved by the municipality’s Wastewater Conveyance Division until the Driftsands sewer line has sufficient additional capacity. Furthermore, a portion of the existing sewer line passes through premises belonging to Airports Company of South Africa (ACSA). As ACSA is anticipating the expansion of Chief Dawid Stuurman Airport, a portion of the Driftsands sewer line must be diverted to accommodate a future runway. The Drift Sands Collector Sewer is primarily a gravity line and is made up of different
pipe materials like fibre cement, concrete and high-density polyethylene (HDPE). With the upgrade, NMBM chose to install concrete HDPE lined pipes, with chambers and manholes lined with Fondag C and HDPE liner to protect the infrastructure from attack against biogenic corrosion. The majority of the Driftsands Collector Sewer Project’s funding has come from National Treasur y through the Urban Settlements Development Grant. A portion
Melanie Geyer, project manager: Planning and Research Division, Nelson Mandela Bay Municipality
