5:40pm Saturday 4 October 2025
Boil water notice and information for food businesses in the Rototuna water supply zone (see map)Â
On Saturday 4 October 2025, Hamilton City Council issued a Boil Water notice following a positive test for E. Coli during routing testing at the Rototuna Reservoir.
The notice will be in place for a minimum of three days, or until three consecutive days of compliant test results.
The positive test was from a single test. Further testing is underway at the reservoir and throughout the network.
What this means for food businesses
A boil water notice doesn’t mean your business can not continue to operate, providing you can meet the steps needed to operate safely.
A boil water notice means that the tap water supply may be contaminated with harmful bacteria like E. coli, and it’s not safe to use without boiling first. As a food business owner, this has important implications for how you operate.
Water for food prep and cooking: You must boil water for at least one minute before using it to wash produce, prepare food, or make drinks. Alternatively, use bottled or commercially treated water.
Handwashing: Staff should wash hands with boiled or bottled water. If using tap water, it must be boiled first.
Cleaning and sanitising: Any equipment, utensils, or surfaces that come into contact with food must be cleaned with boiled water or a safe alternative. Sanitising solutions should be made with boiled water.
Ice and beverages: Do not use ice made from tap water. Discard any ice or drinks prepared with unboiled tap water.
Hamilton City Council has established an Incident Management Team as we investigate this issue, and we are working closely with the water regulator Taumata Arowai, the Ministry of Health and other agencies.
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4:30pm Saturday 4 October 2025
We have issued a boil water notice for the Rototuna water Supply Zone as a single positive E.coli test result was confirmed in routine testing this morning.
The area affected is shown in the attached map (this has now been updated above).
We immediately established an Incident Management Team, notified the regulator Taumata Arowai, and are conducting further tests and checks across our network.
Until notified, Rototuna residents are advised to boil water before using it for:
drinking (including making of sachet juice/drinks);
making ice;
food preparation;
brushing teeth; and
preparing infant/toddler formula.
Electric jugs with a cut-off switch can be used as long as they are full – allow the water to come to the boil and wait for it to switch off (do not hold the switch down to increase the boiling time). Water can also be placed in a clean metal pan and brought to a rolling boil for one minute. Boiled water should be covered and allowed to cool in the same container.
People with severely compromised immune systems, infants, pregnant women, and some elderly may be at increased risk. These people should seek advice about drinking water from their health care providers. If you have specific health concerns, consult your doctor or Healthline 0800 611 116.
If you have other houses or tenants on your property please advise them of the contents of this notice.
If you have any questions or concerns, please contact Hamilton City Council directly on 07 838 6699.
Further updates will be shared on this page and on our social media channels as they come available.
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