Private well owners are being reminded to get their drinking water tested.
Environment Canterbury (ECan) is encouraging well owners to test their drinking water regularly because many contaminants can't be seen, smelt or tasted.
The council’s water and land science manager Dr Elaine Moriarty says regular testing was one of the simplest ways to protect household health.
“Private wells can become contaminated with harmful bacteria and viruses, such as E. coli, as well as nitrate, heavy metals and other chemicals,” she said.
“Some contaminants occur naturally, while others come from human activities.
“Because many can't be seen, smelt or tasted, testing is the only way to know for sure if your well water is safe to drink.”
Landowners with their own private drinking water supply are responsible for ensuring the water is safe to drink.
Depending on how many people use the water supply, you may need to register it with the water regulator, Taumata Arowai.
ECan recommends testing private well water every three months for E. coli, once a year for nitrate and every three years for heavy metals and organic chemicals.
Additional testing is recommended after heavy rain events or flooding.
“Floodwater can contain sewage, animal waste, agricultural runoff and disease-causing microorganisms that can enter wells or groundwater supplies,” Dr Moriarty says.
“That fast-flowing water can wash contaminants into groundwater supplies, especially if the wellhead casing is not securely sealed, which is why it’s important to check your wellhead regularly,” she says.
The wellhead should be elevated, at least half a metre above the ground, surrounded by a concrete apron, and securely sealed.
Testing your private drinking water supply is straightforward, so it's just a matter of getting into a regular habit of testing.
Well owners can order a testing kit from an accredited laboratory, collect a sample following the instructions provided, and return it to the lab for analysis.
The "Don't guess – test!" campaign aims to show that testing is important and easy to do, by providing practical information about what to test for, when to test, and how to do it.
For more information:
Visit ECan's private drinking water supplies webpage: ecan.govt.nz/wellwater
Visit Taumata Arowai for accredited laboratories, public guidance on drinking water safety, or to register your drinking water supply: taumataarowai.govt.nz.