Phase 1 of the R474 million Milnerton Bulk Sewer upgrade well on its way
19 April 2023
Councillor Zahid Badroodien, the City’s Mayoral Committee Member for
Water and Sanitation yesterday, 18 April 2023, conducted an on-site visit to
see the progress of Phase 1 of the Milnerton Bulk Sewer upgrade.
This project consists of two phases with a total project cost of R474 million. Phase 1 consists of the construction of a new bulk sewer and sand trap and screening facility in Montague Gardens to increase the capacity and reliability of the bulk sewer system. Phase 2 entails future trenchless rehabilitation of the existing Montague Drive Bulk Sewer.
The construction period for Phase 1 is from 1 March 2023 until 12 February 2025.
In 2015, a condition assessment (study) of the bulk sewers in the Blaauwberg and Milnerton areas, indicated that the structural condition of the Montague Drive Bulk Sewer had deteriorated significantly due to sulphuric acid corrosion. This meant that the sewer poses a high risk of structural failure.
'Due to its location - under the Montague Drive roadway, means that a sewer collapse on this pipeline could be fatal for motorists and can create substantial interruption to traffic flow in Montague Gardens.
'As a result, the Montague Drive Bulk Sewer was earmarked as one of the critical sewers for upgrading and rehabilitation,' said the City's Mayoral Committee Member for Water and Sanitation, Councillor Zahid Badroodien.
The study concluded that the Montague Drive Bulk Sewer was operating at full capacity and found it insufficient to accommodate the future upstream requirements of the catchment. An additional bulk sewer in Montague Gardens was then recommended to supplement the Montague Drive Bulk Sewer.
'The installation of a sandtrap and screening facility at the Koeberg Road Pump Station will improve the operation of the bulk sewer system by improving the pump station's performance and reducing pump breakages caused by foreign objects entering the pump station sump.
'Also, improving the Koeberg Road Pump Station's operation will reduce the number of sewer spills into the Diep River and relieve environmental pressure on the City,' said Councillor Badroodien.
Considering the findings and recommendations of the aforementioned condition assessment, this major project consisting of two construction phases were initiated.
The scope of work for Phase 1:
- Micro-tunnelling of a new 3,78km long Montague Gardens Bulk Sewer 970mm in diameter around the eastern and northern boundaries of the Montague Gardens industrial area.
- Micro-tunnelling of a new 300m long bulk outfall sewer of 1 350mm diameter at the Koeberg Road Pump Station to accommodate the combined flow of the existing Montague Drive Bulk Sewer and the new Montague Gardens Bulk Sewer.
- The construction of a new sandtrap and screening facility at the Koeberg Road Pump Station.
- Extending and diversion of the existing 700mm diameter Edgemead Bulk Sewer and 450mm diameter Century City Bulk Sewer into the new infrastructure.
The scope of work for Phase 2:
- Trenchless rehabilitation of the approximately 4km long existing 700mm diameter to 975mm diameter Montague Drive Bulk Sewer.
- The diversion of the Century City Bulk Sewer back into the rehabilitated Montague Drive Bulk Sewer.
End
Published by:
City of Cape Town, Media Office
