Working towards safe drinking water for everyone

Safe drinking water coming out of a kitchen mixer tap. Safe drinking water – available to everyone – is a fundamental requirement for public health. Drinking water can contain harmful germs such as Cryptosporidium, Giardia, Campylobacter, Salmonella and E. coli O157 that can cause serious illness.

Community and Public Health works on behalf of the Ministry of Health to facilitate improvement in the quality of community drinking water supplies throughout Canterbury, South Canterbury and the West Coast. Staff encourage the protection of drinking water sources and improvements in water quality through the following actions:

Download or read a frequently asked questions (FAQ) sheet:

Read the 2011 CDHB Position Statement on the Canterbury Water Management Strategy [124KB PDF].

Read the 2003 CDHB Position Statement on Water Fluoridation [113KB PDF].

Poor condition of reservoir at root of Akaroa contamination incident

Christchurch City Council media release: 19th April 2021
An internal review into the drinking water contamination that affected Akaroa and Takamātua earlier this year identifies the poor condition of the L’Aube Hill Reserve reservoir as the likely cause.

“Unfortunately the poor condition of the reservoir and the lack of mesh coverings on the overflow pipes allowed animals to get into the reservoir, which led to the contamination,” says Head of Three Waters Helen Beaumont.

“This was a serious contamination incident that should not have happened and we apologise for it. We have learned some important lessons and are working to ensure this cannot happen again.

“We have taken on board the recommendations of the internal review and are re-examining the way we allocate and prioritise improvement works to our drinking water operation sites. A dedicated project manager has been appointed to oversee this programme because the supply of safe drinking water is of utmost importance to this Council.”

The Council had identified the ageing L’Aube Hill Reservoir as a high risk in its Akaroa-Takamātua Water Safety Plan, which was approved by the Drinking Water Assessor in November 2020. The inspection that discovered the contamination at L’Aube Hill on 9th February 2021 was being undertaken as part of a detailed condition assessment of the reservoir, in accordance with the Water Safety Plan.

However senior Council staff were not advised until 12th February. At that point the Council’s contamination response process was quickly activated – including the issuing of a boil water notice – and the Drinking Water Assessor notified.

Three cases of water-borne diseases were reported to the Canterbury Medical Officer of Health by people who visited Akaroa in the days leading up to the issuing of the boil water notice.

Ms Beaumont says the delay in notifying the Drinking Water Assessor and Medical Officer of Health about the contamination event was not acceptable.

Report into review of health response to lead contamination released

Beehive media release: 16th April 2021
The Government welcomes the findings from a rapid review into the health system response to lead contamination in Waikouaiti’s drinking water supply.

Sample results from the town’s drinking-water supply showed intermittent spikes in lead levels above the maximum acceptable value. The source of the contamination is still under investigation by the Dunedin City Council.

“New Zealanders have every right to expect that their drinking water is safe,” Associate Minister of Health, Dr Ayesha Verrall said.

“I asked the Director-General of Health to conduct a rapid review using independent expertise to look into how local and central government health agencies responded to elevated lead levels. I’m pleased the overall finding of the report showed that the health response was timely and appropriate. The actions of the health agencies meant the risk to the public’s health was reduced.

“The report made several recommendations to reduce the chance of this happening again. They include improvements to several areas in the current and proposed regulatory framework for drinking water, such as better reporting by water suppliers and a review of the process for Public Health Units to access expert advice.

Water restrictions currently in place

As of 23rd April 2021

  • Christchurch and Banks Peninsula: Level 4 water restrictions for Akaroa, Duvauchelle and Takamatua. Christchurch City Council is closely monitoring weather forecasts and water demand in Banks Peninsula with the hopes of being able to lower restrictions in the near future.
  • Westland District: Level 1 restrictions for Arahura.

Check your local council website for the latest information on restrictions in your area.

Health risks of nitrates in drinking water from private bores

High levels of nitrate in drinking water may pose a significant health risk for the foetus of pregnant women and formula-fed infants through using drinking water.

Regional councils monitor the nitrate levels in groundwater around their region. Environment Canterbury creates and updates maps showing the nitrate levels across Canterbury.

  • Green areas are where nitrate concentrations in groundwater are always below the Maximum Acceptable Value (MAV).
  • Red areas are where nitrate concentrations in groundwater are above the MAV most or all of the time and therefore alternative water sources should be used for drinking.
  • Yellow areas are where it is not known if a sample collected from a well will have nitrate concentrations exceeding the MAV and testing is recommended.

Get your water tested if you live in a yellow nitrate area

Private well owners are responsible for their own water monitoring, and what frequency to test their water. It is recommended that you test your water when you purchase a property with a private well or bore or drill a new well or bore. Follow-up testing is prudent every 6 to 12 months.

It is important to get your water tested for nitrates if you are pregnant, or have a formula fed baby under 6 months and are on a private bore or well in a ‘yellow’ area. Testing is the only way to detect nitrate as it is tasteless, odourless and colourless.

There are several laboratories that are able to test for nitrate. Often the laboratory will be able to provide you with a suitable bottle and instructions for taking the sample yourself. The result may take a few days.

Documents and Forms for Water Suppliers


Download or order resources from the Community Health Information Centre.


Contact a Drinking Water Assessor for more information:

Ph: +64 3 364 1777
Fax: +64 3 379 6125

Ph: +64 3 687 2600
Fax: +64 688 6091

Phone: +64 3 768 1160
Fax: +64 3 768 1169

Maps of Nitrate Risk in Canterbury Drinking Water

Environment Canterbury creates maps of nitrate risk for the water zones across Canterbury. These maps are current as at March 2020.

Download or view the map to find out the nitrate risk from private wells or bores in your region or area.

Download the full ECan report on Risk maps of nitrate in Canterbury groundwater [PDF].

What to do if your area is under a boil water notice

A range of hazards and emergencies may contaminate your water supply and make it unsafe to drink or use. A boil water notice will be issued when this happens.

People living in the affected area should boil all water until further notice for:

  • drinking;
  • making up infant formula;
  • preparing food; and
  • cleaning teeth.

Find out more about boiling water and hand hygiene when your water is contaminated (Ministry of Health).

Getting the facts on fluoride

The Ministry of Health strongly supports water fluoridation as a safe, effective and affordable way to prevent and reduce tooth decay across the whole population. Most tooth decay is preventable, and water fluoridation is a simple way to prevent it.

The most recent nationwide New Zealand survey into oral health showed 40 percent less tooth decay on average for children living in fluoridated areas compared with non-fluoridated areas.

The NZ levels of fluoride used in community water fluoridation are carefully monitored and within the guidelines of the World Health Organization and other public health agencies.

Page last updated: 04/05/2021

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