/ 9 March 2023

Faecal pollution severely contaminates SA’s rivers, dams – report

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Highly polluted reservoirs in Gauteng and the North West, including Hartbeespoort Dam, should be fenced off because of the health risks they pose to people and animals from blooms of toxic cyanobacteria. Photo: Getty Images

South Africa’s rivers and dams have a “severe” problem of microbial contamination from faecal pollutants; 53% of the sampled sites are a risk to people’s health risk if crops eaten raw are irrigated using this water, a new government report states.

Only 42% indicated a low risk, according to the department of water and sanitation’s National State of Water Report 2022

Full-contact recreational activities such as swimming, washing laundry and baptisms “should be discouraged in these water resources that are highly polluted”. The report found that 64% of the sampled sites were unsuitable for recreational activities and that using these sites “would be associated with a high risk of infections”.

The contamination of water resources by faecal pollutants poses significant risks to human and animal health because numerous pathogens are associated with faeces. The report noted that faecal coliforms and E coli are the best indicators for the assessment of recent faecal pollution and indicate the potential presence of pathogenic bacteria, viruses, and parasites. 

“Surface water resources are usually not suitable for domestic activities such as drinking without any sort of treatment and this is evident in the data,” the report said. “The microbiological results indicate that all the collected samples had high microbial contamination and the water from that source was not suitable for drinking.”

This would pose a high risk of infection to humans if water was consumed directly from the source. Treating the water at the household level can reduce the potential health risk in situations where water is not severely polluted. There was a low risk of infection if water was consumed after limited treatment in 42% of the sampled sites. 

“The findings are in line with what we are seeing and what we are finding across the country,” said Ferrial Adam, the manager of WaterCAN, an initiative of the Organisation Undoing Tax Abuse (Outa), the anti-corruption advocacy nonprofit. The amount of sewage and pollution flowing into the country’s rivers is unacceptable, she said. 

“There has to be greater urgency to deal with this. What we need from the DWS [department of water and sanitation] are the plans to improve the situation but also stronger measures to hold those responsible accountable — whether they are charged criminally, dismissed. We need greater testing, including issues such as hepatitis, and we need to be testing fresh food products that are being irrigated with polluted water.”

She said the statistics and figures in the report were not surprising, given the state of wastewater treatment plants in South Africa “and that we know that the government is a big polluter”. 

Adam said that the river ecosystem is being depleted because of pollution and that a stronger action plan was required. “Our local government is failing and if we leave it to the local government this is not going to be sorted out.”

At the recent Sustainable Development Goal Six mid-term review, the department celebrated that the basic provision of water services has increased delivery from 64% in 1994 to 88% in 2022 and that the figure for safely managed supply — free of faecal and priority chemical contamination — currently stands at 66%. 

But, said Mariette Liefferink, the chief executive of the Federation for a Sustainable Environment, “the situation on the ground is very different. Many communities continue to stand ankle deep in raw sewage because of dysfunctional wastewater treatment works.” 

The report contains the results of the department’s Blue Drop and Green Drop assessments, which were published last year. For the Blue Drop programme assessment on drinking water quality, 144 water services authorities comprising 1 186 water supply systems were evaluated. The results showed that 48% of water supply systems are in the low-risk category. The large proportion of low-risk supply systems are in the Gauteng and Western Cape, while 34% of systems reside in the high-risk and critical risk categories.

The Green Drop programme audited the wastewater treatment facilities of 144 municipalities with most rural municipalities struggling to score more than 50%. Only 5% of rural municipalities achieved this score in comparison to 75% of systems in Gauteng. 

“To do the certification does not improve the water situation,” Liefferink said. “They [the department] will have to enforce non-compliance.”

Eutrophication is the process of excessive nutrient enrichment of water that results in problems associated with excessive macrophyte, algal, or cyanobacterial growth.

According to the report, hypertrophic sites, which have high nutrient concentrations where plant growth is determined by physical factors and water quality problems are serious, include Rietvlei Dam, Roodeplaat Dam and Florida Lake in Gauteng, and Hartbeespoort Dam, Roodekopjes Dam, Olifantsnek Dam, Bospoort Dam, Klipvoor Dam, Klein Marico Poort Dam, Lotlamoreng Dam and Modimola Dam in North West.

Bon Accord Dam (Gauteng) was assigned an eutrophic state, while the Vaal Dam was assigned to be “mostly mesotrophic”, which means “intermediate levels of nutrients, fairly productive in terms of aquatic animal and plant life and showing emerging signs of water quality problems”.

Poor water quality, including eutrophication, has already caused significant damage to economic growth and the well-being of South Africans, the report said, noting urgent intervention is required to slow the trend. 

“The sites characterised by serious eutrophication problems are characterised by catchments hosting densely populated urban developments, poorly functioning sewer networks and wastewater treatment works.”

It said eutrophication is being worsened by insufficient wastewater treatment infrastructure maintenance and investment; deteriorating ecological infrastructure; recurrent droughts driven by climatic variation, and an “inescapable need” for water resource development; inequities in access to safe sanitation, against the backdrop of a growing population; water use regulation “that is not consistently and adequately protecting South Africa’s water resources” against eutrophication; and a lack of skilled water scientists and engineers.

The report cited how, because of various problems, data is lacking in many areas of the country, with the chemical water quality condition of 2017-18 cited as the most recent period for which there was adequate information to provide a water quality depiction of the situation across South Africa. 

The main inorganic water quality issues of concern on a countrywide basis include elevated salinity, the failing wastewater treatment works in some municipalities and acid mine drainage

“When salt levels are high and the water is used for domestic purposes, such as drinking, it can lead to serious health risks in infants under the age of one year (blue baby syndrome); individuals with heart or kidney disease who have been put on a salt-restricted diet; and those with chronic diarrhoea. Excessively high levels of salts in water can also affect water infrastructure by corroding water distribution pipes leading to increased maintenance and replacement costs.”

Kevin Winter, of the Future Water Institute at the University of Cape Town, said: “Our biggest problem is not so much water supply challenges, as big as that is, I think it’s going to be about water quality in the next 20 to 30 years and we need to keep that on the top of our dashboard.”

South Africa’s cities are expanding rapidly. He said Cape Town, for example, has a population of about five million people and by 2050, that number would double. Massive investments in dealing with wastewater will be required in areas with high density populations. 

“If that water runs off into the soils, into the rivers, that sort of thing, we’re going to find ourselves in serious problems with respect to our rivers and our local coastline as well. That’s true for every metro city in South Africa that is expanding so quickly, but it’s hard to keep up with all the investments.”

Winter added that there is growing concern about thousands of contaminants in the country’s waterways from various sources including drugs and pharmaceuticals, which are in microscopic concentrations. “We’re not quite sure how much — even at low levels of concentrations — how they’re going to affect the human body.”