Several people, including school groups, became seriously ill after drinking contaminated water at Hanmer Springs Forest Camp in North Canterbury.
Health authorities have confirmed the outbreak was caused by STEC bacteria found in the campground’s private water supply.
Health New Zealand’s National Public Health Service identified 10 confirmed and 37 probable cases of illness, with six people requiring hospital treatment.
The Water Services Authority said the incident highlighted the importance of maintaining safe drinking water systems, particularly at remote campgrounds that rely on untreated or surface water sources.
A boil water advisory was issued on 17 September after the Authority was alerted to the outbreak.
Staff visited the site to assess the water system and confirm consumer advisories and safety measures were in place.
Water Services Authority Head of Operations Steve Taylor said it was vital that visitors to campgrounds follow boil water notices and that operators ensure their systems are well maintained.
“Many remote campgrounds across New Zealand rely on boil water notices,” Taylor said. “Operators should make sure their signage is visible and up to date, and keep an eye on their water sources for any changes that could increase risks.”
Taylor said the Authority had directed the campground to maintain its boil water advisory until effective water treatment was installed.
“This is a serious illness, and we acknowledge the significant impact on those who have been sick and those who are still recovering,” he said. “The campground operator has been cooperative and is providing bottled drinking water while ensuring clear signage is in place.”
The Authority’s on-site assessment found the campground’s water treatment system did not adequately manage all source water risks, as the supply comes from a shallow stream likely to contain microorganisms, particularly during heavy rainfall.
Taylor urged all water suppliers to review their safety measures ahead of the summer season and encouraged any unregistered suppliers to visit the Authority’s website for guidance.
The Water Services Authority continues to work with the campground operator, Hurunui District Council, and Health New Zealand’s National Public Health Service on the response.
