A sewerage spill into the Jukskei river from Northern Waste Water Works is the worst in 25 years.
Environmental consultant and chairman of the Jukskei Catchment Area Management Forum, Paul Fairall, said the sewerage effluent spill started on 24 October. Many environmental and public health activists were angered at the slow response from Johannesburg Water.
“The sewage spill severely raised the level of e.coli in the small river and had a far-reaching affect on the community. It could take decades to resolve as e.coli can live in silt for up to seven years,” said Fairall.
Sewerage had overflowed from an emergency dam number 02, at the water treatment works between the R511 and R114 roads, east of Heronbridge college.
“The Jukskei river is usually a brownish colour, but I have never seen it this black before. The e.coli presence is at the highest possible level.
Joburg Water fits belt presses
Johannesburg Water spokesman Millicent Kabwe said, “The sewerage spill is due to a current [BEE: Black Economic Empowerment] contract to install and commission new belt presses into the existing system. This work caused solids to build up in the system that resulted in reduced treatment capacity.
“The rain season also contributed to overflow and spillage. The problem will be solved once the new belt presses are fully operational and high solids build-up in the system is cleared. If all goes well, the new belt presses should be fully operational by the end of next week.”
Kabwe said several months of backlog in the system would then start clearing and a “great improvement is expected in December.”
Four sludge digesters
Fairall warned Fourways residents to should stay clear of the Jukskei river banks and wetlands. “Only two of the four sludge digesters were working to handle 430 mega-litres of sewage flow per day”.
However, Kabwe said all four sludge digesters were working. Fairall warned Johannesburg Water that when Helderfontein Estate and Steyn City would be fully developed and functional, “this water works would have an even greater volume of sewerage to treat. It needs a more effective system.”
Jukskei, Hartbeespoort, Hennops link
Jukskei river is indirectly linked to Hartbeespoort dam and Hennops River, which could result in e.coli laden water reaching 13 000 ha of irrigation systems in the Pretoria and Brits areas in North-West province.
Fairall said the dam produces a third of South Africa’s fresh produce due to major irrigation schemes at Brits and further north.
Kabwe recognised that the spill could affect Hartbeespoort dam, but said mitigation plans were being explored to prevent this.
She said Joburg Water was monitoring the environmental health of rivers upstream and downstream since the spill started.
Fairall noted that several infomal settlements used water from the Jukskei River. The 10 000 ha Rhenosterspruit conservancy is also downstream of the spill, and chairman Helen Duigan said the Jukskei river was already under severe pressure from tons of littler and effluent dumped into it at Alexandra and Diepsloot. – looklocal