THERE is more to cleaning a badly polluted river than meets the eye, according to Dr Abie Khan, Quality and Food Safety Manager for Willowton Group.
This entails removing both refuse such as plastic, paper and cardboard, metal and alien vegetation as well as improving the water quality.
Khan said the group’s third river clean up on February 15, just ahead of the 2022 Dusi Canoe Marathon, revealed that reducing the rubbish in the river actually brought down levels of E. coli which are an ongoing health hazard.
“We have taken samples of the water before the clean-up and samples post the clean-up to see the difference we are making. We will use this to highlight the importance of getting the stakeholders and communities along the entire river involved this initiative,” said Khan.
Samples taken before and after the clean-up revealed that the very high levels of E. coli prior to the removal of waste dropped significantly afterwards but then began to rise again.
Willowton Group has partnered with Pietermaritzburg based Talbot Laboratories, a SANAS accredited testing facility, to assess the quality of the water in the Baynespruit.
Micole Martens, General Manager of Talbot Laboratories, said that samples taken prior to February 15 were high at 648,800, but dropped to 98,040 six hours after clean-up. Unfortunately, they started increasing the next day.
This demonstrated that a physical clean up allowed for better flow and “cleaned” the river. The counts started increasing once more because the pollution from upstream continued.
“Things like crisp packets, plastic bottles and even trolleys often make their way into rivers,” Martnes said. “Unfortunately, these things are intentionally thrown into the river. Other times, litter blows rubbish out of bins or landfill. This makes its way into the watercourse.”
Khan said this showed that no matter how the litter gets there, it’s crucial to remove it. “Physical pollution can have a devastating impact on the ecosystem as can be seen by the high E. coli counts before clean-up.
“By carrying out regular litter picks, we can help alleviate the burden of physical pollution on our rivers and other habitats.”
Khan confirmed that this latest clean up by Willowton Group yielded over some 300m of a 1km stretch 2.217 tons of plastic, metals for recycling and vegetation. The group is currently exploring the process of composting the vegetation removed from the Baynespruit for use in the Willowton garden.
Martens stressed that both physical pollutants and bacterial and chemical pollutants that were not visible needed to be removed from the Baynespruit to make it safe for local communities without access to clean water via the municipality to use it.
“Rivers contain microbial life and pollutants from a range of natural sources. For example, livestock animals are kept in the vicinity of a river. They can defecate directly into the waterway. Even without direct access, rainwater can mix with manure and other animal waste before draining into the river as runoff.”
Martens added that, during periods of heavy rain such as that experienced in the KZN Midlands, storm water from treatment works and storm drains from the sewer network resulted in rainwater mixed with raw sewage being discharged into rivers.
“This means that the majority of what gets flushed down the toilet or poured down the sink – including non-biodegradable items like wet wipes – ends up polluting the river. In theory, the rainwater should dilute the raw sewage and screens should remove gross solids — however, the existing infrastructure can’t cope with our rapidly increasing population, leading to many discharging more often than they should,” she said.