Whakatāne District Council has acknowledged the frustration that repeated boil water notices are causing Rūātoki residents.

Following a news item this week in which Pūkāea reporter Herewini Waikato spoke to Rūātoki whānau reporting vomiting, diarrhoea and stomach cramps, which they believe may be linked to their water supply, the council issued an update on the township’s drinking water supply.

So far this year, three boil water notices have been issued for Rūātoki drinking water, each following significant storm events.

“We understand that boil water notices are frustrating for residents and can create uncertainty for whānau,” said transition director Three Waters Nic Johansson.

“These notices are issued as a precautionary public health measure. During and after heavy rain, increased turbidity, or cloudiness, in the source water can reduce the effectiveness of ultraviolet treatment used to disinfect the supply.” 

Drinking water suppliers are required to have multiple treatment barriers in place. Under normal conditions in Rūātoki, the supply is treated using ultraviolet light and chlorine. If one treatment method is not operating effectively, a boil water notice must be issued until both systems are confirmed to be working properly and the water is safe to drink. 

“Boiling water is a simple and proven way to make drinking water safe,” Mr Johansson said.

“When a notice is in place, water should be brought to a rolling boil for at least three minutes or boiled in an electric jug for the three-minute duration.” 

Though some households had installed home filtration systems, all water from the town supply still had to be boiled during a notice, regardless of whether there was a household filter.

While a boil water notice is in place, the council undertakes daily water quality testing across the network and closely monitors turbidity, chlorine levels and other indicators. Monitoring occurs 24 hours a day through electronic systems, alongside regular on-site testing. Notices are lifted only once the supply is confirmed safe to drink without boiling. 

At this stage, the council has not been advised by the Ministry of Health of any waterborne illness linked to the Rūātoki supply. If any such issues were identified, the local public health unit notifies the council and The Water Services - Taumata Arowai, the national water services regulator. 

Residents who rely on private bores or alternative water sources are encouraged to ensure these are properly maintained and tested, particularly during and after heavy rainfall. 

Mr Johansson said work was underway to improve the long‑term resilience of the Rūātoki water supply.  

The current supply draws water from a bore located near the river. Over time, changes in the river’s path mean the bore is more susceptible to increased turbidity during heavy rain events. 

More than seven alternative bore sites have been investigated. Findings show that retaining the existing source and investing in higher-technology treatment is the most effective long-term option. 

Funding has been set aside in the council’s Long-Term Plan to progress upgrades, including a new water treatment plant. Construction investigations are expected to begin from late 2026, with commissioning to follow once design and procurement are complete. 

The council has also been trialling a membrane and micro-filtration system offline for potential use at the future Rūātoki pump station. The system is designed to physically remove fine particles from the water and reduce turbidity during heavy rain events. 

“Trials to date have been promising, but the system is not yet operational,” Mr Johansson said.

“Until upgraded treatment is in place through a new water treatment plant, boil water notices will continue to be required during and after heavy rainfall events.”