What should you do during a boil-water notice?

Short answer. During a boil-water notice, bring tap water to a full rolling boil for 1 minute (3 minutes above 6,500 feet), let it cool, and use it, or bottled water, for drinking, cooking, brushing teeth, ice and infant formula ¹². Showering is fine if you avoid swallowing water ¹⁵. Filtered water, including from a pitcher filter, must still be boiled ¹.

Who issues a boil-water notice, and how do you hear about it?

The notice comes from whoever runs or oversees your water supply. In the United States, advisories are issued by water utilities or government agencies when tap water is or could be contaminated ¹. In Canada, the responsible provincial, territorial or local authority decides, based on a site-specific risk assessment ². In England and Wales, the water company issues the notice to consumers in the affected area; for a private water supply, it comes from the local authority ⁵.

A boil-water notice is about germs. It is different from a "do not drink" advisory, which covers chemicals or toxins that boiling does not remove, and from a rare "do not use" advisory, when you use bottled water for everything ¹. Read which one you have received, and follow the advice from your local officials ¹.

How long do you boil the water?

The general science of boiling, bleach and portable filters is in the Phaenyx guide on making water safe to drink. Under a notice, let the water cool before use to avoid burns ¹, and take care to avoid scalds, particularly around young children ⁵⁶. Store cooled water in a clean, covered container in the fridge ²⁶. The DWI says to discard it if not used within 24 hours ⁵; Québec allows up to 3 days in the fridge or 24 hours at room temperature ³.

What needs boiled or bottled water?

Use boiled or bottled water for anything you swallow or that touches food eaten raw:

• drinking, and making drinks, juices, tea and coffee ¹³;
• brushing teeth ¹⁵;
• preparing food and washing fruit and vegetables ²³;
• making ice cubes ²⁵;
• water for pets ¹⁵.

Health Canada adds that ice, drinks or uncooked foods already prepared with possibly contaminated tap water should be thrown out ². During any advisory, do not drink or use water or ice from fridge and freezer dispensers connected to the water line ¹. Québec lists tea and coffee among the drinks to prepare with boiled water ³, which includes the water you put in a coffee maker.

Why isn't a pitcher filter enough?

The CDC says to boil tap water even if it has passed through a home filter or a pitcher filter ¹. Québec states that water softeners, activated carbon systems and filtering pitchers are not designed to kill harmful micro-organisms ³. A filter is not a substitute for boiling under a notice.

What can you still do with tap water?

Across agencies, tap water stays usable for:

• Showering and bathing, as long as you avoid swallowing water ¹²⁵⁶.
• Washing hands with soap and water, in many cases ¹³. Follow the advice from your local officials ¹.
• Laundry, as usual ¹⁵.
• Cooking foods that boil a long time, such as pasta and soups ³.
• Dishes. The CDC says dishwashers are generally safe if they have a sanitizing cycle or a final rinse of at least 150 °F (66 °C) ¹. To wash by hand, wash and rinse in hot water, soak for at least 1 minute in 1 teaspoon of unscented liquid bleach per gallon of warm water, then air dry ¹. The DWI simply says to use hot water and dry dishes thoroughly ⁵.

Health Canada sets stricter rules during a confirmed waterborne disease outbreak: sponge baths only, and for dishes by hand a 1-minute soak in 20 mL of unscented bleach per 10 L of water followed by at least 4 hours of air drying ².

What about babies and young children?

The CDC suggests considering sponge baths for babies and young children, to reduce the chance of them swallowing water ¹. Health Canada says infants, toddlers and people with weakened immune systems should be sponge bathed ², and NSW Health offers sponge baths for children as an alternative ⁶.

For feeding, the CDC says breastfeeding is the best option and, for formula, to use ready-to-use formula if possible ¹. Health Canada states that water should be boiled at all times when preparing infant formula ², and NSW Health says formula should be made with cooled boiled water ⁶. Sanitize baby bottles ¹. If your baby was premature or has a medical condition, ask your doctor or nurse about feeding during the notice. The Phaenyx guide on infant supplies covers what to keep at home.

What do you do when the notice is lifted?

A notice is lifted only when the authority says so. In Canada, that requires at least two consecutive sets of negative bacteriological samples, collected at least 24 hours apart ². Then:

1. Flush your pipes. Québec says to run all cold taps for a few minutes, and to flush garden hoses and outdoor taps ³. Alberta Health Services gives at least 5 minutes per tap, or 10 minutes in an apartment building ⁴.
2. Clear the ice. Throw out any ice made with possibly contaminated tap water ². Québec says to empty, wash and disinfect ice machines ³; for fridge ice and water dispensers, follow the manufacturer's flushing and cleaning instructions ⁴.
3. Service filters and softeners. Clean and sanitize filters following the manufacturer's directions, and run water softeners through a regeneration cycle ⁴. Québec also refers you to the manufacturer for home treatment devices ³.
4. Check the water heater. Here agencies differ. Québec says it is not necessary to drain a hot water tank ³. Alberta Health Services says to drain and refill hot-water tanks set below 45 °C ⁴.

What official agencies recommend

• United States (CDC): Boil 1 minute, or 3 minutes above 6,500 ft; boil filtered water too; avoid fridge dispensers; ready-to-use formula if possible ¹.
• Canada (Health Canada, Québec, Alberta): Boil 1 minute, at least 2 minutes above 2,000 m; always boiled water for formula ². After lifting, flush for a few minutes (Québec) or at least 5 minutes (Alberta); the two disagree on draining the water heater ³⁴.
• United Kingdom (DWI): The water company issues the notice; bring water to a rolling boil, cool naturally, keep it in the fridge and discard it after 24 hours; showers, baths, laundry and toilets as normal ⁵.
• Australia (NSW Health): A rolling boil, which an automatic kettle achieves; cooled boiled water for formula, ice, teeth and pets; dishes in hot soapy water or a dishwasher ⁶.
• France (ARS): Instructions are set notice by notice. In Mayotte in February 2025, the ARS told residents of three villages to boil tap water for 5 minutes or use chlorine tablets ⁸, longer than the 1 minute used in North America ¹².
• World Health Organization: A rolling boil is sufficient to inactivate pathogenic bacteria, viruses and protozoa ⁷.

Frequently asked questions

Is it safe to shower during a boil-water notice?

Yes for most people, if you keep water out of your mouth ¹⁵. Health Canada advises sponge baths for infants, toddlers and people with weakened immune systems, and sponge baths only during a confirmed outbreak ².

Can I use my dishwasher?

The CDC says yes if it has a sanitizing cycle or a final rinse of at least 150 °F (66 °C) ¹. Health Canada gives at least 65 °C for the final rinse during an outbreak ².

Does an electric kettle boil water long enough?

NSW Health says kettles with automatic shut-off switches bring water to a rolling boil ⁶. The CDC and Health Canada specify 1 minute at a rolling boil ¹², so where your local notice follows that rule, keep the water at a rolling boil for 1 minute.

How long does a boil-water notice last?

Until the authority lifts it. In Canada, lifting requires two consecutive sets of negative samples taken at least 24 hours apart ², so the final sampling alone takes at least 24 hours. Keep a few days of stored water so you are not boiling everything.

Next step: your plan

Check the drinking-water risks where you live, country by country. Your Phaenyx plan's "Water and air" section sets out the water and air risks for your postal code, and the Phaenyx Safe app keeps the boil-water reflex card offline, ready when the notice comes. Build your Phaenyx plan.

Sources

1. Centers for Disease Control and Prevention (CDC) — Drinking Water Advisories: An Overview — https://www.cdc.gov/water-emergency/about/drinking-water-advisories-an-overview.html (accessed 2026-10-27)
2. Health Canada — Guidance for Issuing and Rescinding Boil Water Advisories in Canadian Drinking Water Supplies — https://www.canada.ca/en/health-canada/services/publications/healthy-living/guidance-issuing-rescinding-boil-water-advisories-canadian-drinking-water-supplies.html (accessed 2026-10-27)
3. Gouvernement du Québec — Drinking water contamination or shortage — https://www.quebec.ca/en/public-safety-emergencies/emergency-situations-disasters-and-natural-hazards/what-to-do-before-during-after-emergency-disaster/drinking-water-contamination-or-shortage (accessed 2026-10-27)
4. Alberta Health Services — Boil Water Order lifted for Town of Olds — https://www.albertahealthservices.ca/news/Page17786.aspx (accessed 2026-10-27)
5. Drinking Water Inspectorate (DWI) — Receiving a Boil Water Notice — https://www.dwi.gov.uk/receiving-a-boil-water-notice/ (accessed 2026-10-27)
6. NSW Health — Water quality - What to do if a boil water alert is in place — https://www.health.nsw.gov.au/environment/water/Pages/bwa-what-to-do.aspx (accessed 2026-10-27)
7. World Health Organization (WHO) — Boil water (technical brief WHO/FWC/WSH/15.02) — https://www.who.int/publications/i/item/WHO-FWC-WSH-15.02 (accessed 2026-10-27)
8. Agence régionale de santé (ARS) Mayotte — L'eau du robinet à Mayotte est désormais de nouveau conforme à la qualité pré-cyclone (communiqué, 20 February 2025) — https://mayotte.ars.sante.fr/media/135357/download?inline= (accessed 2026-10-27)