Our drinking water
Canterbury has some of the best drinking water in the world, but no water supply is completely without risk.
Water can be contaminated by bacteria, viruses, nitrate, metals and other chemicals. Some contaminants occur naturally, while others come from human activities.
If you’re on a reticulated supply, your local council or water supplier will assess those risks and make sure your drinking water is safe. If you have your own well, the responsibility rests with you.
Who helps ensure our water is safe to drink?
Our role as a regional council is to monitor surface water and groundwater across the region and to regulate activities that might affect water quality. However, specific monitoring of water supply sources is the responsibility of water suppliers.
We report on progress towards the Canterbury drinking water targets on behalf of all partners in the Canterbury Water Management Strategy
Drinking water is regulated by Taumata Arowai, a Crown entity created in March 2021. Taumata Arowai has responsibility for setting the drinking-water standards and the rules that water suppliers must follow.
The current drinking water standards were set by the Ministry of Health in 2018 (DOCX file, 1 MB).
Reticulated water supplies
If your water is provided by someone else, that provider must have drinking water safety plans that identify any risks to their supplies and how those risks will be mitigated.
For most people, that water supplier will be their local council. For more information about your council water supply, visit your council's drinking water webpage:
- Kaikoura District Council
- Hurunui District Council
- Waimakariri District Council
- Christchurch City Council
- Selwyn District Council
- Ashburton District Council
- Timaru District Council
- Mackenzie District Council
- Waitaki District Council
- Waimate District Council.
Many people have their water supplied by a privately-owned scheme. If your water is supplied by a privately-owned scheme, you should contact the scheme's owner directly for more information.
Household water supplies
If you get your water from your own private household supply, such as a well or spring, or use a rooftop rainwater collection system, then it is your own responsibility to make sure your water is safe to drink.
If your water is provided by someone else, that provider must have drinking water safety plans that identify any risks to their supplies and how those risks will be mitigated. For most people, that water supplier will be their local council, but many residents get their water through privately-owned supplies.
Keeping your private water supply safe
If you live in a rural area, you may not have access to a reticulated water supply and need to supply your own water. You may have your own private well, get your water from a spring, or collect rainwater from your roof. If this is the case, then you are responsible for ensuring your own supply of water is safe and you should take the following actions:
- Check the historical use of the land to understand possible groundwater contamination risks.
- Learn where your well is located and ensure it’s in good condition.
- Make sure your well head is secure, free from debris, and fenced off from animals.
- Regularly test the water supply by taking a sample and sending it to a lab for analysis.
Testing your water supply
There is potential for a range of contaminants to reach groundwater. Testing for these is important because drinking contaminated water can have serious health consequences. Contaminants that can be found in our water include the following:
Bacteria and viruses
Viruses or bacteria like E. coli can come from faecal material from grazing animals or septic systems, or from farm effluent spread on the land, which can infiltrate groundwater supplies.
You should test for E. coli quarterly, especially following significant rainfall.
Nitrate can enter groundwater from farming activities, principally through animal urine and fertilisers, as well as from wastewater disposal and landfill.
We recommend testing nitrate levels annually, preferably during spring, when nitrate levels tend to be higher.
For more information on nitrate, visit our Nitrate – what’s the story? page.
Heavy metals and organic chemicals
Heavy metals include cadmium, lead, manganese and arsenic. Organic chemicals include petroleum compounds, industrial solvents and pesticides. These contaminants can come from a variety of sources including old sheep dips, landfills and industry. Arsenic and manganese also occur naturally in some parts of Canterbury.
A test for a full range of heavy metals and organic chemicals is more expensive, but only needs to be done once.
- Read our brochure on private well testing and protection (PDF File, 1.06MB)
- Contact your local water zone committee.
- Find out more about drinking water safety.
Christchurch has a plentiful supply of fresh clean drinking water. In fact, Christchurch's aquifers are replenished with 375 billion litres of water each year, most of which is not used and flows out to sea. We work with the community to help ensure we protect our fresh water now and for generations to come. People from across our region are working together as kaitiaki to protect and improve our water resources.
Around three-quarters of Christchurch’s groundwater comes from the Waimakariri. Water seeps through the river bed and into the groundwater, which flows toward the city at a rate of about 25 metres per day. Rain that falls onto the land west of Christchurch also contributes to the groundwater system. In addition, recent information suggests that some of the deepest groundwater beneath Christchurch may come from rain and irrigation water that falls on the land to the north of the Waimakariri River.
This groundwater is famously pure at its source. To ensure it stays pure, the area above the aquifer is subject to strict land-use rules under the Canterbury Land & Water Regional Plan to minimise the risk of contamination. That’s why you’ll find recreational parks and very low intensity stock grazing in this part of Canterbury.
The Christchurch City Council is the only organisation that can apply to take more water from our aquifer, and it can only do so to use for community drinking water supply. Existing consents can be transferred if new uses won’t have an increased environmental effect.
For information regarding chlorination of the Christchurch drinking water supply, see the CCC website.