Water sample results taken by the Garden Route District Municipality on Monday, 4 March, in the Knysna estuary have indicated nine of the 15 areas sampled are non-compliant with the Department of Water Affairs regulations. The Department of Water and Sanitation guideline for recreation stipulates the acceptable level of E.coli bacteria must be lower than the 500 cfu/100ml mark.
Cfu stands for colony-forming unit, an estimate of viable bacteria or fungal cells in a single sample. Results are thus reported as CFU/milliliter for liquids.
Results collected at the following sites were compliant and not affected at this stage: The Heads, Bollard Bay, the Point, Salt River, Crabs Creek and Bigai. Sites exceeding Water Affairs guidelines include areas sampled at the Ashmead channel, Queen Street, the Train station, Long Street, Green Hole, Bongani and outside the Waste Water Treatment Works.
SANParks has also taken deepwater samples and results look positive which means animal and plant life in those areas might not be affected by the spikes, such would include the Knysna seahorse, the Knysna Gobi and others. This water is also compliant and safe to use according to recreational guidelines. Areas around Leisure Island, The Heads, the Waterfront, the main channel and Belvidere are still safe for recreation.
Taplin adds, "In the past when we have experienced such spikes in E.coli levels in the water, the Action Pollution Committee (a multi-stakeholder initiative made up of SANParks, the Knysna Municipality, Garden Route District’s Health division and the Knysna Basin Project) was able to investigate the source of the problem."
Last week, the Knysna Municipality confirmed there was a chemical contamination at its Wastewater Treatment Works (WWTW) dating back as far as February 2019 and acknowledged this as a cause for concern. In a statement dated (7 March 2019), the municipality added ‘the normal readings at the WWTW are usually between 1 and 10 mg/L and over the last few weeks, readings of up to 836 mg/L were recorded. These types of chemicals kill the good bacteria introduced to balance the E.coli levels in the water before it is released and as a result of the above, the latter has increased significantly.
SANParks is working together with the Knysna Municipality and Garden Route District Municipality to investigate the sources of pollution as well as measures to address the impacts of this pollution. Further sampling is underway this week to identify the possible sources of oil/grease pollution.
