The City of Cape Town is spending R9.1m on advanced technology to rehabilitate the Langa interceptor sewer – one of the oldest sewers in Cape Town that serves approximately 64,500 residents.
As part of the City’s commitment to building a well-run city through infrastructure upgrades, this rehabilitation project will benefit the residents of Langa by ensuring capacity for future developments. The number of sewer overflows and spillages should be reduced and the City’s Water and Sanitation Department will also spend less on maintenance.
The Langa sewer upgrade project will run over 26 weeks and is a massive undertaking involving the pipeline being blocked off, cleaned and prepared for the liners to be installed. To give one an idea: an adult person can almost stand upright at the highest point of the egg-shaped sewer.
The Langa interceptor sewer is the major collector sewer serving the Langa area and is more than 70 years old. Now that the sewer has reached the end of its service life, it must be rehabilitated to extend its lifespan by at least another 60 years.
‘This is a critical project for us as ageing infrastructure requires regular and costly cleaning so upgrading leads to a more cost effective service. Of course, no amount of improved technology will work if there continues to be illegal dumping’ said Councillor Ernest Sonnenberg, Mayoral Committee Member for Utility Services.
Over the years the City has found many objects in the sewer system, ranging from cement and suitcases to trolleys and sheepskins. Only through a consistent partnership between the City and the community will the benefits of this rehabilitation project be felt.
Trenchless technology - that is being bought in from the United Arab Emirates – will be utilised to line the sewer pipe with egg-shaped glass reinforced polyester (GRP) liners. This means that nothing will be dug up resulting in minimal disruption to the community and cost saving. The egg-shape and the glass reinforced polyester liners means that friction will be limited and speed of flow enhanced. Moreover, the GRP-liners are resistant to corrosive conditions associated with sewers and there should be no cost to maintain it.
Once rehabilitated, the sewer will have more than sufficient capacity – up to 502 litres per second – which is equal to the filling of an Olympic size swimming pool every one and an half hours.