The Methven community drinking water supply will be without fluoride for about three months, while a new water treatment plant for the town is being completed.

The new membrane water treatment plant will be like other modern plants and use fluoride in the form of Hydrofluosilicic Acid (HFA); the old plant uses Sodium Fluoride and Council’s last stocks are likely to be used up in the next month.

Infrastructure and Open Spaces Group Manager Neil McCann said Council had made exhaustive but ultimately unsuccessful efforts to find enough Sodium Fluoride to use in the old water treatment plant until the new plant is commissioned in August.

“We’ve looked at importing more Sodium Fluoride but that is only available in very large quantities. The two tonnes we would need to buy would have lasted three years, but it also might not have been able to be shipped in time. We’ve looked at other water suppliers but most have already upgraded their plants to use HFA and we’ve also looked at hiring equipment on a temporary basis to use the HFA.

“Ultimately, the most commonsense decision is to temporarily stop adding fluoride to the town’s water supply for a couple of months.”

Methven’s water supply has been fluoridated since 1970 and the community has supported fluoridation, through referendum, to help prevent tooth decay.

While fluoride is temporarily out of the supply, residents are being encouraged to use fluoridated toothpaste, and talk to their family dentist if they have concerns about their oral health.

Methven Community Board chair Kelvin Holmes said the new plant was on track to be completed by August.

“Our community has been looking forward to this plant and an improved water supply for a long time, and commissioning the new plant will restore fluoride to the Methven supply.”

Mr McCann said Council had contacted the office of the Director General of Health to advise them of the situation.

“A recent amendment to the Health Act means that Councils no longer make decisions about whether community water supplies are fluoridated or not. That is now decided by the Director General of Health, who is progressively asking all Councils to fluoridate their supplies.

“The amendment also said any local authority already fluoridating a drinking water supply must continue to do so, so on paper we are not fulfilling this obligation. But we have given the Director General plenty of notice about the situation and done our very best to find a resolution.”

The new membrane water treatment plant is currently under construction, and once complete, will house equipment to better filter water coming into the supply and is expected to bring about the end of boil water notices after a heavy rain event.