Gauteng’s ‘rivers of disease’

HAZARDOUS: UNTREATED SEWAGE, INDUSTRIAL WASTE, TOXIC CHEMICALS FLOW INTO DAMS

- Seth Thorne

CLOGGED AND REEKING. A wastepicker collects recyclable rubbish on the banks of the Jukskei River in Johannesburg.

(Picture: Seth Thorne)

Unsafe levels of coliform bacteria found in 21 out of 23 river samples.

A long the banks of the Jukskei River in Alexandra, Johannesburg, a man wades through murky water searching for bottles and scrap to sell. He says his name is Petrus and prefers not to have his surname published.

“The water smells very bad,” he says. “Luckily, there are always things to recycle coming down the river, so I try to collect,” he said. “It gets dangerous after it rains as the water gets rough.”

Across Gauteng, rivers carry untreated sewage, industrial waste and toxic chemicals through densely populated communities before draining into larger river systems that feed dams such as the Vaal and Hartbeespoort.

River pollution in the province has become an environmental and public health crisis, driven by failing wastewater treatment works, ageing sewage infrastructure, rapid urbanisation, illegal dumping, industrial runoff and pollution from mining.

Major rivers including the Jukskei, Klip and Hennops, as well as parts of the Vaal River system, now carry sewage, solid waste, heavy metals and other contaminants. In many areas this has resulted in dangerous levels of E. coli and harmful algal blooms.

A December 2025 report by civil society group WaterCAN tested 59 water sources across Gauteng and found 39 were unsafe for human consumption.

Each sample was tested for chemical and microbiological contamination such as E. coli.

The sources are classified as unsafe when these levels exceeded acceptable limits.

Looking specifically at bacterial contamination, WaterCAN analysed 23 river samples and five dam samples across Gauteng.