Fluoridation

Response from Simeon Brown Minister of Health – 4 March 2025

Letter sent to Simeon Brown Minister of Health – 13 February 2025

Fluoridation workshop - 10 February 2025

Fluoridation update - 27 June 2024

The Health (Fluoridation of Drinking Water) Amendment Act 2021, enabled the Director-General of Health to direct local authorities to add fluoride to a drinking water supply.

Any local authority that receives a direction to fluoridate one of its drinking water supplies must take all practicable steps to ensure the optimal level of fluoride for oral health benefits is present in that supply.

In July 2022, the Director General of Health directed Rotorua Lakes Council to fluoridate its two larger water supplies – Central and East by 30 April 2024.

Rotorua was one of 14 local authorities directed to fluoridate water supplies at that time.

Rotorua Central (serving 42,500 residents) and Rotorua East, including the Lake Ōkāreka community, (population 10,330). Click here to view the Central and Eastern Water Supply Areas (PDF 811KB)

Rotorua has eight supply areas; Ngongotahā, Hamurana/Kaharoa, Reporoa, Mamaku, Rotoiti, Rotomā, Rotorua East and Rotorua central. Rotorua East and Rotorua Central will be fluoridated by 28 March 2025, as required by the Ministry’s direction, and the remaining supply areas are under consideration by the Director-General.

The details about the legal basis for this direction, including the recent High Court judgement and the New Zealand Bill of Rights Act 1990, are on the Ministry of Health’s website. Council receives a number of directives from central government which we are legally required to follow. Council has a legal obligation under the Health (Fluoridation of Drinking Water) Amendment Act 2021 to comply with the direction to introduce fluoride to the water supply.

The Health (Fluoridation of Drinking Water) Amendment Act 2021 amended the Health Act 1956 to enable the Director-General of Health to direct local authorities to fluoridate drinking water supplies. A local authority that receives a direction to fluoridate is not required to consult on any matter related to the directive.

No. When a local authority receives a directive it must comply. Non-compliance is an offence that carries a maximum penalty of $200,000 and up to $10,000 per day for continuing offences.

Rotorua Lakes Council officers have undertaken due diligence through enquiries to legal and health agencies to ensure Council and elected members have access to appropriate advice on potential legal liabilities. Council will be acting within its legal responsibilities in adopting the implementation of the fluoridation directive.

Council will make a final decision on whether or not to follow the directive at their full council meeting on March 26. Not following the directive could result in fines for the council.

The cost to upgrade the two treatment plants is about $3m which is being funded through the Government’s $11.3m funding pool for capital projects associated with the directive. Had council not taken up this funding, the cost would have fallen on ratepayers.

Ongoing operational costs for monitoring and fluoridation of the two supplies council has been directed to fluoridate is estimated to be $160,000 per year which will be funded through council’s annual renewal and maintenance budgets.

For further information on community water fluoridation visit Ministry of Health website (health.govt.nz).

Rotorua Lakes Council is using hydrofluorosilicic acid (HFA) and it will comply with the Water NZ Good Practice Water NZ Good Practice Guide for the Supply of Fluoride for Use in Water Treatment.

A document is supplied with every bulk delivery of hydrofluorosilicic acid certifying its compliance with the Water NZ Guide. This is supported by laboratory analyses of every batch and quarterly composite samples for parameters as specified in the Water NZ Guide which also includes the concentration of fluoride in the product.

HFA is added to the water at a controlled rate via a dose pump. The concentration of fluoride in the water is also measured continuously as it leaves the treatment plant.

The delivery system design and construction has been undertaken and monitored by Ministry of Health - approved consultants, and peer- reviewed by independent experts.

The consultants will be required to certify that all systems are fully operational and meeting the Water NZ Guide.

The direction from the Ministry of Health requires Rotorua Lakes Council to fluoridate at optimal levels between 0.7 parts per million (ppm) and 1.0 ppm, or in the range of 0.7-1.0 mg per litre of drinking water.

Dose monitoring and alarm systems will be installed and incorporated into Council's existing system which has been controlling and monitoring treatment systems in full compliance with the stringent Drinking Water Quality Assurance Rules - (PDF, 930KB) which are mandatory for water suppliers.

In regard to fluoride dosing, there are three independent controls:

• A dosing pump controlling the rate at which HFA is introduced to the system. This pump is calibrated regularly to ensure it is delivering the correct dose.
• An online fluoride concentration sensor which continuously measures the concentration of fluoride in the water, and is set to generate a cascading series of alarms if the concentration is found to be outside specified limits.
• A “day tank” system that measures the amount of HFA required for one day's dosing. It is not possible for any more than the contents of the day tank to be dosed in any 24-hour period.

Council will also be implementing an additional voluntary sampling programme of fluoride levels in the network, along with our existing sampling programme for free-available chlorine. pH and microbiological indicators which is managed Council's Ministry of Health and IANZ accredited laboratory.

Fluoride has no taste or smell so residents will not notice any difference to their drinking water.

There are several types of filters available on the market, including alumina activated filters, reverse osmosis filters, and distillation filters, among others. Each of these filters has different capabilities when removing fluoride from water. We recommend investigating effectiveness of any filter before buying.

Council staff are investigating the possibility of providing unfluoridated filling stations at Caledonia Rd and Puarenga Park.