Tests done by the Council for Scientific and Industrial Research (CSIR) have confirmed that groundwater at Stinkwater, north of Pretoria, is unfit for human consumption and can make you sick.
Experts have been studying groundwater in the area for more than three years, the SABC reported.
The South African Human Rights Commission (SAHRC) warned in June about the quality of water in Hammanskraal.
According to the broadcaster, 144 water samples were tested and traces of E. coli were found in more than 80% of the samples.
CSIR senior scientist Wouter Le Roux said the water also contained high levels of nitrate.
Le Roux said people drinking the water could become ill or get infections.
In April, Tshwane mayor Stevens Mokgalapa, who came into office in February after taking over from Solly Msimanga, promised to tackle the water issues.
Mokgalapa said it was “no secret that we inherited an administration that contaminated our streams and dams”.
