Looking for current boil water advisories, notices and orders in Ontario? This page tracks active alerts in one place, explains how advisories work in Ontario, and links the official provincial drinking water authority you should double-check in an emergency. When a notice is in effect, use boiled or bottled water for drinking, cooking, ice and brushing teeth until authorities lift it.
In Ontario, boil water advisories are issued by the water utility together with Ontario Ministry of the Environment, Conservation and Parks (MECP) & Public Health Units. A notice is usually preventive — issued after a main break, pump failure or pressure loss — but it can also follow confirmed contamination in samples. Advisories are lifted only after repairs and two clean sample rounds are verified, which is why most last one to three days.
Active boil water advisories in Ontario
The list below is refreshed automatically from official feeds and editor-verified updates. Each notice links to the source so you can confirm details.
Official drinking water resources for Ontario
- Ontario Ministry of the Environment, Conservation and Parks (MECP) & Public Health Units
- Ontario Ministry of the Environment, Conservation and Parks (MECP) & Public Health Units — current advisories page
- U.S. EPA — Ground Water and Drinking Water
What to do when a Ontario advisory is issued
Follow the issuer’s instructions first. The standard playbook, aligned with CDC and Health Canada guidance: bring tap water to a rolling boil for one minute (three minutes above 2,000 m elevation) before drinking, preparing food, making ice or brushing teeth; throw away ice made before the advisory; sponge-bathe small children; and flush household pipes, ice makers and filters once the all-clear is announced.
Boil water advisories in Ontario: FAQ
How do I find out if my area in Ontario is under a boil water advisory?
Check the live notice list on this page first, then confirm with Ontario Ministry of the Environment, Conservation and Parks (MECP) & Public Health Units and your local water utility — utilities deliver the binding notice to customers by phone alerts, text, door hangers and local media. Notices in Ontario usually follow main breaks, pressure loss, flooding or failed water samples.
How long do boil water advisories last in Ontario?
Most last one to three days: the time needed to fix the cause, flush the system and collect two consecutive rounds of clean bacteriological samples. Large storm or flooding events can extend that to a week or more. The advisory is over only when the issuer officially lifts it.
Who is most at risk during a Ontario boil water advisory?
Infants, adults over 65, pregnant people and anyone with a weakened immune system are most at risk from waterborne organisms. During an advisory they should drink only boiled or bottled water — including ice made during the advisory — and use bottled water for formula.
Can I shower during a boil water advisory in Ontario?
Healthy adults can shower as long as they avoid swallowing water and keep it out of the mouth and eyes. Sponge-bathe small children with boiled, cooled water, and use boiled water if you have open wounds or a weakened immune system.