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].

Precautionary Boil Water Notice in Akaroa

Canterbury DHB media release: 14th February 2021

Canterbury DHB Medical Officer of Health Dr Cheryl Brunton says there is potential for people to develop gastro illnesses if they drink water from the Akaroa reservoir without first boiling it.

“While chlorine will kill bacteria in the water supply, the possum and bird carcasses found in the reservoir may have introduced other contaminants (protozoa) which aren’t killed by chlorine. They are, however, killed by boiling your water,” Dr Brunton said.

Protozoa are single cell organisms also known as parasites which include cryptosporidium and giardia. Symptoms of cryptosporidiosis or giardiasis are similar to other gastro illnesses and can include diarrhoea, stomach pain, cramps, nausea, vomiting, headaches and a high fever.

Call your own general practice team, or Healthline on 0800 611 116 if you are concerned about your health. You can call either number 24/7 for free health advice.

“Both cryptosporidium and giardia can cause gastro symptoms that may persist for weeks rather than days, and medical advice should be sought. While there’s no specific treatment for cryptosporidiosis, there is for giardia.

“Symptoms of both illnesses usually appear 2 to 10 days after becoming infected. However giardiasis symptoms can appear up to 25 days after being infected.

“It’s important for people with any gastro illnesses that cause vomiting and diarrhoea to keep their fluids up, be meticulous about handwashing and drying, and avoid preparing food for others while you have symptoms. People with more severe symptoms including fever, or who are finding it difficult to keep fluids down should seek medical advice. This is especially important for babies and young children and the elderly.

“The simple message is: If you live in Akaroa, do not drink the tap water. Boil all water before using it for cooking, cleaning your teeth or for drinking. Or use clean, safe water from one of the tankers trucking water in from Christchurch, or use bottled water.

There have been no notifications reported to Community and Public Health of illness due to the water in Akaroa as of Sunday 14 February.

Water restrictions currently in place

As of 25th February 2021

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

Think water sense this summer: Water like you oughta

Using a watering can to water plants in a garden.Summer is here, so it’s time to start thinking smart about how we use water, so we can all keep enjoying a reliable water service through the hotter and drier months.

The National Institute of Water and Atmospheric Research is predicting a hot, dry summer after a drier than usual winter. This means now is a good time to get into good habits and be smart about how we use our water to help ensure there is no need for restrictions.

The household demand for water in Canterbury generally doubles in summertime compared with winter – mostly because of people watering their gardens and lawns.

Being water smart also helps ensure you’re making the most of the water you use, being good for your garden and getting the best value from your water rates.

Tips for managing your water use:

  • Check hoses or taps for leaks.
  • Make sure sprinklers are watering the plants – not the driveway, footpath or buildings.
  • Use a watering can or hose. This is the most accurate way to water, plus it can be very relaxing!
  • Use or install a timer on your irrigation system or sprinkler.
  • Water for shorter periods such as three five-minute intervals over a couple of hours rather than continuously for 15 minutes. This will let the soil absorb more water.
  • Water your garden and lawn every few days rather than every day.
  • Water your garden early morning or late evening, when it’s much cooler. Watering in the middle of the day during hot weather or on a windy day is not recommended.
  • There’s no need to water the berm. Let it die off during summer to save money on your water rates and wear and tear on your lawn mower.

Director of the Christchurch Botanic Gardens Wolfgang Bopp says making small changes to watering habits can add up to a big difference. “Lawns don’t need much water, if any, and there’s no real reason to be watering roadside berms. Grass is tougher than most people think. If it does turn brown over summer, it‘ll go green again in autumn.”

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

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

Contact the Drinking Water Assistance Programme Facilitator:

Kathryn Russell
Ph: +64 3 378 6811
Fax: +64 3 379 6125

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: 26/02/2021

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