Cape Town – The City’s Water and Sanitation Directorate is investing R25 million towards major infrastructure refurbishment at Wemmershoek, one of the City’s 12 water treatment plants.
Twenty concrete filters are being restored as part of the bulk water Infrastructure Refurbishment and Replacement Programme.
The refurbishment at the Wemmershoek water treatment plant (WTP) started in April 2023 and is due to be completed by the end of December 2024.
Wemmershoek WTP treats water from Wemmershoek Dam, which was built in 1957 in order to increase water supply to the city and adjacent local municipalities. The dam has a capacity of 58 644 megalitres.
The treatment plant supplies water through the 1 525mm Wemmershoek pipeline, to both Drakenstein and Stellenbosch municipalities. There are farmers and other industrial consumers along this pipeline, as well as the northern suburbs of the City of Cape Town.
The treatment plant supplies Glen Garry reservoir, which in turn provides for the Tygerberg reservoirs.
To ensure the plant remains operational, work is being conducted in four phases, splitting up the team to work on four or five filters only, at a time.
The project is currently in its second phase of completion.
Each phase of the project takes about three months to complete, and then another month is required to commission the filters back into operation.
Each filter measures 12x4m in surface area and 2.5m deep. Individually, the filters can treat about 12 million litres of water per day (ML/d).
This process is best managed outside of the peak summer demand period.
Mayco member for water and sanitation Zahid Badroodien said: “Careful planning needed to take place before this complex refurbishment could begin, to ensure that water supply would not be completely disrupted while the work is ongoing.”
“The scale of the investment in maintaining the integrity of the water treatment plant is testament to ensuring that our residents continue to have reliable, quality water supply,” said Badroodien.
To undertake the refurbishment project, production flow at Wemmershoek WTP was reduced from 200 MLD to 150 MLD (and in some cases even down to 120 MLD), which unfortunately put strain on the pressure supplied to the Wemmershoek pipeline.
The objective of the bulk water Infrastructure Refurbishment and Replacement Programme is to ensure that, in the long term, water infrastructure is well maintained in order to support growing water supply demand.
“Water users along this pipeline have contributed significantly to the steady progress of the project. They have been encouraged to be aware of the major maintenance having an impact in their area and advised to use water wisely, thereby reducing the strain on supply during this time,” said Badroodien.
The City regrets any inconvenience caused and is monitoring operations closely to help reduce disruptions as far as possible.