‘Unspecific’ readings mar better estuary figures
Water-quality readings of the Knysna estuary taken last month at first glance indicate a great improvement in the quality of the water compared to three months ago – but some “unspecific” readings could indicate a worrying decline.
According to an update published on 8 October, estuary recreation points indicate very low levels of E. coli, which includes Bollard Bay at 12/100ml, The Heads at 20/100ml and The Point at 7/100ml. The acceptable limit according to the department of water affairs is 500/100ml.
But Salt River indicates the reading is >300/100ml (greater than 300), which could mean almost any figure, including that above 500.
Culvert measurements show similar unspecific readings.
Requested to explain the confusing readings, Garden Route District Municipality’s Health Services stated that the laboratory that undertakes the analysis every month has been requested to give exact readings from now on, as in the past.
‘No reason for improvement’
The service said there is no particular reason for the improved readings. ‘’A water body can change at any particular time,” its statement said.
Health Services also said that as the summer holiday approaches, more
frequent sampling will be undertaken so that any sudden pollution can be addressed and communicated to the public.
According to Sanparks spokesperson Nandi Mgwadlamba, this month their team will follow up to establish exactly how much more above 300/100ml was recorded for October, and also stated that not much can be done about last month’s readings.
She clarified that E. coli in natural bodies of water can come from livestock, wildlife or humans, and is either shed directly into the water or washed into it by rainwater, sewerage or other water flows.
‘System can fluctuate at any time’
“The Knysna estuary is a natural system where levels of bacteria can fluctuate at any time,” she said, adding that Knysna is one of a few towns with an established multistakeholder committee to tackle pollution in the estuary.
It was previously reported that one of the biggest culprits of pollution in the Knysna Estuary was the municipality’s wastewater treatment works (WWTW), which includes Brenton-on Sea, Belvidere, Rheenendal and Sedgefield.
The municipality earlier this year received a warning from the Western Cape department of water and sanitation, due to its alleged failure to take measures to prevent pollution.
The notice stated that “numerous correspondences … were sent to the municipality regarding the contraventions dating back to 2014 following site inspections by both the department and the Breede-Gouritz Catchment Management Agency (BGCMA)”.
‘Action plan requested’
It also states that the last notice of noncompliance dated 19 May 2015 was issued detailing the department’s concerns over potential pollution, and requested that the municipality submit a comprehensive action plan in response to the concerns highlighted.
“More recent site inspections at the aforementioned sites conducted on 30 August 2017 confirmed that, with the exception of upgrades at Sedgefield WWTW, conditions across the remaining WWTWs had either remained the same or had worsened.
Based on the final effluent results loaded onto the department’s Green Drop System, Knysna, Belvidere, Sedgefield and Rheenendal WWTWs have consistently failed to comply with final effluent quality standards,” states the document.
Department spokesperson Sputnik Ratau told KPH this week that municipality did finally submit a plan.
The department is considering the content thereof and having discussions regarding its feasibility, Ratau said.
‘Barking up the wrong tree’
But according to chemical engineer John Buchanan, these attempts to rectify pollution problems constitutes barking up the wrong tree. “The original cost for the WWTW was in the region of R36million,” he told KPH recently. ‘’The municipality has now spent R80-million and they are still going about it the wrong way,” said Buchanan.
He explained that the treatment is incorrect because the “outside consultants appointed by the municipality do not understand what’s going on”.”The plant is just not working,” he said.
Buchanan claimed that he has offered his expertise to the municipality since 2007, but has been continuously “shut down”.
He told KPH this week that he is in the process of finalising a report on the condition of the Knysna WWTW, to present to the Estuary Forum in coming weeks. He could not divulge details before that.
The municipality did not respond to questions regarding the WWTW by the time of going to print.