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Fluoride decision for Onehunga2 min read

Aug 3, 2022 2 min

Fluoride decision for Onehunga2 min read

Reading Time: 2 minutes

Onehunga Water Treatment Plant will be upgraded for fluoridation. At the end of July, the Ministry of Health directed Auckland Council and its water and wastewater service provider, Watercare, to fluoridate the Onehunga and Waiuku water supplies. Similar directives were also given  to 13 other local authorities around the country.


Onehunga’s water supply comes from an underground spring, and, unlike most of urban Auckland, has never been fluoridated. Opinion has been divided over whether or not it should be fluoridated. Supporters believe it should be, because they consider it the most effective, and safe, public health measure for the prevention of tooth decay. Opponents believe it is a toxin and health risk, and should not be used at all.


In 2001, a local referendum was held so that Onehunga residents could vote for or against fluoridation of the local water supply. Those against adding fluoride won the referendum, and this was the status quo in Onehunga until November 2015, when Auckland Council revisited the issue but again voted against fluoridation of the local water supply.


The decision to fluoridate our drinking water means that the Onehunga Treatment Plant will need to be upgraded and they have until the end of June 2024 to install fluoride dosing systems at the plant. “We’re confident we can meet that deadline,” says Watercare chief operations officer, Mark Bourne.


Although the decision whether to fluoridate water supplies rested with Auckland legacy councils, when Watercare took responsibility for the region’s water and wastewater services in 2010, they retained the position of the legacy councils and made no changes to fluoridation.


“Our responsibility in regards to fluoridation has always been to ensure that where we do dose our treated water with fluoride, it’s done safely and carefully monitored to ensure our water complies with the New Zealand Drinking Water Standards. We’ve been fluoridating water supplies safely since 1966. At the moment about 94% of Auckland’s water is fluoridated.


“We carry out rigorous testing on all Auckland’s water supplies to make sure it is always safe to drink. Our treatment plants use continuous online instruments to monitor fluoride levels in the treated water. And if the fluoride concentration was to deviate from the control limits, alarms are triggered and dosing stops.”