Higher than recommended fluoride levels in the Ōamaru water supply means the pause button has been hit by the Waitaki District Council.

Testing last week indicated levels of 1.07mg/L post-reservoir and 1.08mg/L at South Hill, a council spokesperson says.

The council targets 0.8 mg/L for fluoridation, following the Director General of Health’s directive to fluoridate between 0.7 and 1.0 mg/L. 

Although marginally above the target level, the levels remain within the maximum acceptable value for fluoride in safe drinking water set at 1.5mg/L in the Water Services (Drinking Water Standards for New Zealand) Regulations 2022, the spokesperson says.

Fluoridation has stopped while council Water Services and commissioning contractors Filtec recalibrate the dosing equipment and analyser to ensure water is fluoridated at the targeted level.

Water from the Ōamaru supply will still have fluoride in it until next Thursday (October 24), as the reservoirs and wider network have already fluoridated water in them.

It is anticipated recalibration will be complete by then, and then fluoridation can recommence.

Once fluoridation restarts, the council will perform regular testing at the treatment plant and in the reticulation network with an accredited laboratory, in addition to continuing to use the dosing and analyser recording - which is the requirement for monitoring fluoridated supplies - to ensure it remains within target.

Director General of Health Dr Diana Safarti has been notified that dosing has stopped to allow for this recalibration, the spokesperson says.