A Queenstown Lakes District Council (QLDC) representative says the council was already acting on the issue when a pollution hotline call was made about wastewater overflow during the New Year’s period.

The Wānaka Wastewater Treatment Plant (WWTP) is monitored by automatic processes, alarms and 24/7 on-call support, QLDC media and channels advisor Sam White said. 

When the call was made, QLDC contractors “were aware of the issues and actively working to return the treatment process, including the disposal field, to normal conditions,” Sam said. 

The WWTP overflow was caused by high flows during the peak holiday period.

“This resulted in lower-quality effluent being released to the disposal field via the normal treatment process which in turn caused some treated effluent to break through to the surface of the field,” Sam said.

“Council staff and contractors acted quickly to address the cause and restore performance.”

The WWTP is located on State Highway 6, six kilometres south-east of the Wānaka CBD.

Sam said the overflow occurred in an area inaccessible to the public and it did not enter any body of water. 

Reduced demand has helped restore normal flow.

“Flows to the WWTP naturally reduced in line with visitors leaving after New Year and additional capacity at an adjacent disposal field, already scheduled to come online shortly, will also help.”

Sam said QLDC was completing an incident report, to be shared with the Otago Regional Council (ORC), which will provide more detail on any remedial action required.

Members of the public are encouraged to call the ORC pollution hotline if they believe they have come across an environmental incident. 

In just one day last week, calls alerted the ORC to three separate issues over in Queenstown: domestic wastewater entering a creek, the presence of toxic algae in a different creek, and the discovery of dead ducks in a stream.

The ORC pollution hotline phone number is 0800 800 033. 

PHOTO: Wānaka App