Knysna wastewater sadly lacking

Despite the Knysna Municipality having performed excellently in its drinking water quality management, it seems to have failed dismally with regard to the performance of its seven Wastewater Treatment Works (WWTW).

According to the Department of Water Affairs (DWAF), the Green Drop Report of 2012, which facilitates a transparent way of indicating DWAF’s confidence in municipal management of waste water services, clearly indicated that the highest risk areas for all seven of Knysna’s WWTWs is that of poor final effluent quality, “meaning that the final effluent being discharged from the WWTWs does not meet the standards set by the department”, explained DWAF spokesperson, Malusi Rayi.

To establish a baseline for all municipal WWTWs in the country, comprehensive assessments of all WWTWs in South Africa were completed in 2009. This study resulted in the formulation of cumulative risk values, which in turn provided an indication of the operation risk that a WWTW represents.

“It consequently provided the department with a list of WWTWs posing the highest risk to those posing the lowest risk, and thus providing a clear indication where the department [DWAF] should focus its attention,” explained Rayi.

Cumulative Risk Ratios (CRR) have now become a complementary process to the Green Drop Certification Programme. The department further explained that the risk-based regulatory approach provides early warning signs of plants that contain a certain measure of risk.

The Green Drop Progress Report of 2012 for Knysna Municipality indicated that the wastewater risk rating of six of the seven WWTWs managed by Knysna Municipality had increased. The Wastewater Risk Rating of the seven WWTW are as follows: Knysna 1 – 50%, Sedgefield – 64.7%, Belvedere-Uitzigt – 58.8%, Rheenendal – 62.9%, Brenton-on-Sea (Uitzicht) – 47.1%, Karatara – 41.2% and Knysna 2 – 70.6%.

“Average annual effluent compliance should be at least 90%, and as can be seen from the report, none of the Knysna WWTWs are meeting this requirement,” said Rayi.

Knysna municipal manager, Lauren Waring responded: “The CRR increased because of an overload on the plant due to population growth which was unforeseen at the time of planning and developing the plant. The plant is in the process of being upgraded, and the tender for the mechanical equipment has been advertised.” According to the report, the only WWTW to have improved is Knysna 1 (situated along George Rex Drive). “The reason for this can clearly be seen by significant investment made by the municipality to upgrade and refurbish the WWTW,” said Rayi.

The Knysa 1 WWTW is currently operating at 96.7%, “which is why the municipality has made extensive funding available. Once upgrades are completed the risk rating should further improve,” explained Rayi.

In Knysna executive mayor, Georlene Wolmarans’ recent state of the town address, she said, “Sewerage is a major concern for the municipality going forward for the next five years and this is before major new expenditures will be required on a new treatment works.” She explained that the recent leakage into the estuary had necessitated remedial repairs which would be incorporated into a minor upgrade to enable the works to extend its current lifespan until 2019.

“The cost of this interim phase is some R47 million, with council having to fund approximately R12,4 million on its own.” She added that council is legally obligated to maintain the WWTW’s operation at a level that prevents pollution of one of the world’s great estuaries and said, “We will not shirk our responsibility’s in this regard but this does highlight the fact that technical infrastructure systems such as the one required are financially beyond what this local authority can in reality afford.”

Rayi remarked that six of the seven Knysna WWTWs had no investment made to improve and/or maintain their infrastructure. “While these WWTWs are operating below their design capacity, poor performance could be due to a number of factors including poor maintenance and/or assets management, or poor technical skills/ capacity to maintain the works.”

The department further requires all municipalities to compile an action plan (Wastewater Risk Abatement Plan – W2RAP) to prioritise and mitigate actual and potential risks to the optimal functioning of the WWTW, through the implementation of effective control measures. The Green Drop Progress Report 2012 indicates that Knysna Municpality’s W2RAP has only been roughly drafted. “This needs greater attention, particularly as it seems that very little attention is given to six of the seven WWTWs,” warned Rayi.

“This report now gives the department an indication of where our attention should be focused [and] as this document is available to the public it also provides the municipality with a further incentive/ pressure to ensure that the situation is improved.”

Rayi added, “Our department is currently very closely monitoring Knysna Municpality, ensuring that their W2RAP is completed and adhered to.” He said further that the site visits to Knysna have become more frequent to clearly define areas of weakness and to ensure that those areas are addressed by the municipality. “Audit sampling of final effluent has also been increased,” added Rayi.

In conclusion Rayi said, “Fortunately none of the WWTWs are within the critical risk space, however should the situation not improve the department shall take enforcement action.”

ARTICLE: FRAN KIRSTEN, KNYSNA-PLETT HERALD JOURNALIST

Source: The Knysna-Plett Herald