20 September

The drinking water regulator, Taumata Arowai, has today served a compliance order on the Queenstown Lakes District Council.

A compliance order provides a set of actions a supplier must follow to ensure that serious risks to public health are addressed.

Head of Regulatory, Steve Taylor said that the situation in Queenstown was complex. “The source of the outbreak is still unconfirmed, but on the information available at the moment there is a material risk as it relates to drinking water. We also know that the Two Mile water treatment plant is non-compliant, creating a risk of contamination that is not being appropriately managed.”

“We are working constructively, and with urgency, with the Queenstown Lakes District Council to resolve this issue and give confidence to communities that their drinking water is safe.”

“The lack of a protozoa barrier at the Two Mile water treatment plant creates a serious risk to public health, demonstrated by confirmed cases of cryptosporidiosis affecting consumers in the Queenstown drinking water supply distribution zone served by the plant,” said Steve.

The compliance order issued by Taumata Arowai requires Queenstown Lakes District Council to keep its current consumer advisory (boil water notice) in place until certain things happen.

Those things are different for the part of Queenstown that gets its water from the Two Mile water treatment plant and the part that gets its water from the Kelvin Heights water treatment plant.

The Two Mile water treatment plant has no treatment for protozoa. The consumer advisory (boil water notice) for this part of the supply must remain in place until either:

• treatment for protozoa is in place and operating at the Two Mile water treatment plant; or
• an alternative supply of safe drinking water is made available to all points of supply ordinarily served by the supply.

The Kelvin Heights water treatment plant has treatment for protozoa. However, information recently provided to Taumata Arowai by Queenstown Lakes District Council has raised some doubts about whether this barrier is working. The consumer advisory for this supply will be able to be lifted once Queenstown Lakes District Council has satisfied Taumata Arowai that it is isolated from the rest of the Queenstown supply and that it is performing effectively.

Queenstown Lakes District Council has two water treatment plants (WTP), which supply around 44,708 people with drinking water. The Two Mile WTP and Kelvin Heights WTP takes water from Lake Wakatipu and distributes the water to different supply zones.

The Water Services Act 2021 (the Act) requires drinking water suppliers to ensure the drinking water they provide is safe, this includes a multi-barrier approach to managing risks.

The Drinking Water Quality Assurance Rules which came into effect on 14 November 2022 require this kind of drinking water supply to have a protozoa barrier.

Steve said that Taumata Arowai is aware of around 190 supplies in Aotearoa (serving approximately 13 per cent of the population) that have similar source water characteristics to the Queenstown supply and have reported they do not have a protozoa barrier at the treatment point.

“We will engage with these suppliers to make sure they are appropriately managing their risks.”

“In June, our Chief Executive wrote to all council and government-operated drinking water suppliers and reminded them of their responsibility to meet the requirements of the Act and the Drinking Water Quality Assurance Rules. We will be writing to people operating supplies that appear to not have appropriate multi-barrier treatment options in place.”

“In the meantime, we will continue to work with the Queenstown Lakes District Council and other agencies to monitor emerging information about people experiencing illness in Queenstown and the performance of the Queenstown drinking water supply. We will factor this into our ongoing regulatory decisions and discussion with the Council.

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