Unsafe drinking water is no longer confined to South Africa’s rural margins but has become a widespread national risk, according to a new citizen-science report released by WaterCAN.
The WaterCAN Water Testing Report 2025, compiled by water management expert Professor Anja du Plessis, analysed water samples collected across all nine provinces during the organisation’s annual Testing Week, which coincides with World Water Monitoring Day. The findings paint a troubling picture: in most provinces, the majority of tested water sources were found to be unsafe for human consumption.
Drawing on hundreds of independently collected samples from rivers, dams, household taps, Jojo tanks and other domestic sources, the report confirms that bacterial contamination linked to failing sewage and wastewater systems is now reaching homes and schools.
“Unsafe water is not an isolated rural problem,” the report states. “The risk has already moved into people’s homes via taps and tanks.”
Gauteng and KwaZulu-Natal Among Worst Affected
Gauteng, South Africa’s economic hub, recorded 39 unsafe samples out of 59, including contaminated tap water and Jojo tanks in municipalities such as Sedibeng and Johannesburg. KwaZulu-Natal showed an even higher risk profile, with 16 of 21 samples classified as unsafe, most of them from rivers but including a tap water source in King Cetshwayo District.
In Limpopo, all four samples tested were deemed unsafe, including a tap water source in Waterberg District. Mpumalanga recorded unsafe results in both river and tap water samples, while the Eastern Cape reported unsafe water across rivers, dams and unidentified domestic sources.
Even provinces with stronger water reputations were affected. In the Western Cape, seven out of ten samples were unsafe, mostly from rivers and other untreated sources within the City of Cape Town. The Northern Cape, despite a small sample size, recorded no fully safe water sources.
Sewage Failures Drive Contamination
While most chemical indicators, such as nitrates and nitrites, were generally within acceptable limits, the report highlights widespread bacterial contamination, including E. coli, as the primary health threat. Elevated phosphate levels, often linked to sewage discharge and wastewater effluent, were identified as another persistent red flag across multiple catchments.
Taken together, these indicators point to chronic sewage and wastewater system failures, rather than isolated pollution events. According to the report, South Africa’s water crisis is increasingly about governance, infrastructure collapse and poor system maintenance, not only drought or scarcity.
Calls for Urgent Government Action
WaterCAN is calling for immediate municipal and provincial intervention in affected areas, including emergency clean water provision where domestic sources are unsafe. The organisation is also urging routine, transparent water quality monitoring and stronger public communication to ensure communities understand the risks of untreated water.
“Any tap or tank testing positive for faecal bacteria cannot be considered safe for drinking,” the report warns.
Now in its fourth year, WaterCAN’s Testing Week has mobilised thousands of volunteers nationwide, building what the organisation describes as a “solidarity army of citizen scientists”. The initiative aims to empower communities to test their own water and hold authorities accountable.
As water insecurity intensifies across Africa, the report underscores a growing reality: without urgent investment in wastewater treatment and accountability at the local government level, safe drinking water will remain out of reach for millions, even in urban centres.
