How Long Do I Need to Boil Water When Under a Boil Water Advisory?

Dear Home Ec 101:

I live in Hurricane Country and there are often boiling water advisories after a storm. How long am I supposed to boil the water before it is safe to drink?

~Avoiding the Runs in Ravenel

Heather says:

Boil water advisories are much more common than you may think.

Advisories can be issued if the power is disrupted for an extended period of time. Why? Water needs to maintain a certain pressure in the pipelines to prevent any potentially contaminated groundwater from seeping into microcracks and fissures in the pipes. When the power is out for an extended period of time, generators may fail, and water pumping stations may not maintain adequate pressure in the lines. Line breaks, positive tests for bacterial contamination, and maintenance are other common reasons.

Boil water advisories are NOT issued for chemical spills. In these cases, a DO NOT DRINK advisory will be issued. Boiling water that has been chemically contaminated will NOT make it safe to drink.

Water should be brought to a rolling boil and boiled for one minute*. Begin timing when the bubbles appear and break the surface.

Allow the water to cool and pour it into a clean, covered container.

*If you are above 6500 feet, boil for a full three minutes (water boils at a lower temperature at high altitudes and needs to maintain this temperature for a longer time to ensure the bacteria has been killed).

Please don’t forget that these advisories apply to much more than just your drinking water. Boil water advisories affect water used for toothbrushing, cleaning produce, and ice making. You will also not want to use automatic dishwashers that do not heat the water or do not have a sanitizing setting.

Your pets’ water also needs to be boiled.

Showering is typically safe for adults and teenagers, but young children should be given sponge baths. Use boiled water for cleaning infant and toddlers as they tend to be independent creatures and decide now would be a fun time to lick the washcloth.

Do remind older children to keep their mouths shut while showering, this isn’t the time to get creative and, “See mom, I saved time by showering and brushing my teeth at the same time!” Great.

Dishes can safely be washed in warm water with a small amount of bleach (one tablespoon per gallon).

If your dishwasher has a sanitizing option you can use that, otherwise, hand wash your dishes either in boiled water or water that has been sanitized using bleach.

After the advisory has been lifted flush the pipes by running each cold water tap for one minute. If you have an automatic icemaker, empty it completely and then discard the first three batches.

Remember most filters, such as those in a fridge or that are attached to your faucet are for taste and odors, not harmful bacteria.

While we are discussing basic preparedness remember that if someone does develop diarrhea or vomiting during an emergency that they shouldn’t be only be given plain water. The body loses a lot of electrolytes through vomiting and diarrhea. Your blackout pantry/first aid kit should contain Pedialyte, Gatorade, or oral rehydration salts.

References:
https://www.cdc.gov/healthywater/emergency/drinking/drinking-water-advisories/boil-water-advisory.html
https://www.cdc.gov/healthywater/emergency/drinking/drinking-water-advisories/do-not-drink-advisory.html