A do not drink notice has been issued for consumers of the Lower Waihao rural water supply, including Waikakahi East, after nitrate levels breached the maximum acceptable value for drinking water.
In a statement this afternoon, the Water Services Authority – Taumata Arowai said it had been advised by the Waimate District Council that nitrate levels in the source water for its Lower Waihao rural water supply had breached the maximum acceptable value for drinking water of 50mg/L.
As a result, a do not drink notice was issued.
“An exceedance of the MAV for nitrates poses an immediate risk to some people’s health, particularly pregnant women and babies if they consume the water,” the Authority’s head of operations Steve Taylor said.
The elevated levels of nitrate differ from the maximum acceptable value for arsenic, which has been a recent issue for the Waikato and Auckland regions over the past week. The risk for arsenic was based on long-term exposure.
Taylor said the Waimate District Council was responding to the situation and was using “all available communication methods” to inform consumers that they shouldn’t drink the water or use it for cooking. He also said boiling the water would not make it safe to drink.
An alternative supply of tank water is available, with locations listed on the council’s website.
Taylor said elevated levels of nitrate in the source for the Lower Waihao rural supply are a known and ongoing issue, and the Authority monitors the council’s management of it.
“Since October 2024, Waimate District Council has detected rising nitrate levels in the Lower Waihao source water and has been proactively informing the Authority of the results and its approach in response.
“Source water treatment processes used by Waimate District Council do not significantly reduce the level of nitrate.”
The Authority encouraged private suppliers and domestic self-suppliers with bore sources to have their water tested for nitrate levels by an accredited laboratory.
“Particularly if it is being consumed by pregnant women or babies,” Taylor said.
“The water should also be tested for the presence of bacteria as it is important your water is microbiologically safe.”
“The Authority is monitoring the situation closely and will continue to work with the Waimate District Council to ensure the appropriate steps are being taken to manage the issue.”
On its website, the council said it was “continuously monitoring” nitrate levels and would advise consumers when the water is safe to use.
