Queenstown Lakes District Council (QLDC) has been working to install UV treatment at its Queenstown Two Mile water treatment plant (WTP) in tandem with similar plants in the district which don’t have systems in place to protect against protozoa such as cryptosporidium.

Council-owned water plants in Wānaka, Luggate, and Wānaka Airport also lack a protozoa barrier, which national water regulator Taumata Arowai head of regulatory Steve Taylor said “creates a serious risk to public health”.

Taumata Arowai issued QLDC with a compliance order on September 20 following an outbreak of illness caused by cryptosporidium, which was suspected to be related to the Two Mile WTP.

Read more: Queenstown parasite outbreak raises concerns about Upper Clutha water supplies

Work to design and commission a protozoa barrier at Two Mile has been ongoing since the compliance order, but QLDC property and infrastructure general manager Tony Avery said installing the barrier was only one part of the overall project.

“We’ve been designing systems for other plants in parallel in order to achieve full compliance across the district as quickly as possible,” he said.

“We have also been planning preparation work for the Western Wānaka water intake which will begin this week and include a temporary realignment of the lakeside Millennium Track. 

“We’ll be working with Te Kākano to reinstate and hopefully expand any areas of native planting affected by this work.”

He said the project was a major one for council’s infrastructure, legal and planning staff as well as contractors Fulton Hogan and Veolia. 

“They are completing work in weeks that would typically take many months. We also continue to acknowledge the patience and resilience being shown by individuals and businesses in the affected areas.”

A public health investigation led by Te Whatu Ora Health New Zealand concluded last month that human faecal contamination of the water supply was the most likely source of Queenstown’s cryptosporidium outbreak, which resulted in 72 confirmed cases of cryptosporidiosis.

Meanwhile QLDC will clean and flush the entire network supplied by Two Mile, as well as draining and cleaning Fernhill #1 Reservoir as well as cleaning and inspecting all other network reservoirs, Tony said.

“We’ll also be flushing the piped network to ensure any sediment where cryptosporidium could potentially still reside is displaced.”

While the possibility of contamination during these activities is low, people in affected areas (Queenstown town centre, Gorge Rd out to and including Industrial Place, Fernhill, Sunshine Bay, and Queenstown Hill above Frankton Rd out to and including Goldridge Way and Goldrush Way) have been advised to keep boiling their water. 

Tony said there is currently no need for people in the Upper Clutha, Frankton or other neighbourhoods outside the current area under the notice to boil water.

“In addition, we ask that everyone including commuters and visitors from other parts of the district maintain good personal hygiene – specifically cleaning and drying their hands thoroughly – to help ensure we stamp out the risk of further cases in our community,” Tony said.

A site office established near Fernhill Reservoir and a container to hold the UV system is a temporary system that will be transferred to another treatment plant once a permanent system is completed at Two Mile.  

PHOTO: Wānaka App