Boil Water Advisory: What You Can’t and Can Do

You might be placed under a boil water advisory during natural disasters like ice storms, hurricanes, earthquakes, tornados, and floods. 

Those advisories happen whenever there's a breach in the freshwater supply. Fallen trees, loss of power to processing plants, or even construction that broke the main water pipe can affect the freshwater supply. 

If you're under a boil water advisory, you might be confused about what that means and why you got the advisory. If so, here's what you should know about boil water advisories and how to drink, bathe, wash, and cook safely.

What Is a Boil Water Advisory?

Any time microorganisms infect your community's water, your local government will likely issue a boil water advisory. If that happens, you must change your drinking, bathing, and washing, and cooking practices until the water is declared safe again.

Concerns over water supply contamination cause local governments to issue boil water advisories. Those concerns may include the following:

• Water line breaks
• Water treatment disruptions
• Power outages
• Floods
• Hurricanes

How long the boil water advisory lasts depends on when the water becomes safe to use. 

Also, your government may issue "do not drink" or "do not use" advisories. With "do not drink" advisories, you should not consume community water, even if you boil it. Instead, use bottled water for the following activities:

• Drinking water, including giving water to your pets
• Cooking food
• Making ice
• Brushing your teeth
• Washing produce
• Preparing baby formula

Unless your local government specifies a "do not use" advisory, you may be able to use limited amounts of community water to wash your hands, use the restroom, or take a shower.

How Long Should You Boil Water During an Advisory?

Boiling water is the safest method for preparing safe water for drinking, cooking, or washing. Or you can use bottled water as an alternative to boiling your water.

To boil your water correctly, using a clean pot, bring the water to a full, rolling boil. Let the water boil for one minute if you are at an altitude below 6,500 feet and three minutes if you're above that.

Let the water cool down to a safe temperature before using it. Per the World Health Organization, water temperatures higher than 122 degrees Fahrenheit may cause scalding.

You should also use bottled or boiled water for pets since they can become sick from some of the same germs as humans. However, you can water plants with tap water.

Water Filters and Advisories

Water filters improve water quality by filtering out some impurities, such as sediments like silt, metals like lead, and chemicals like chlorine. Removing those impurities can remove unwanted taste and odor.

But a water filter can't remove microorganisms, like bacteria, from contaminated water. So, you still need to boil the water even if it's filtered, Tamika Sims, PhD, senior director in food technology communications at the International Food Information Council, told Health.

What Can’t You Do During a Boil Water Advisory?

Knowing how not to use tap water that might contain waterborne pathogens is important. Here are some things to avoid until your water is declared safe again.

Don't Drink The Water If You Shower or Bathe

You can shower and bathe during an advisory. However, it's extremely important not to swallow any water.

"During times of inclement weather, there can be low water pressure in the pipes. With this, the groundwater, which is generally not treated against harmful bacteria, viruses, and parasites, can seep into older pipes that have cracks in them," Vidya Mony, MD, infectious disease specialist at Santa Clara Valley Medical Center, told Health.

"These harmful pathogens can then be swallowed when the bath or shower is turned on and make you sick," added Dr. Mony. "This is why it's very important not to swallow any water while taking a bath or shower. It is also important that for children and people with disabilities [to be] supervised during their bath, to ensure that water is not swallowed and to limit the amount of time bathing."

If you need to bathe your children during a boil water advisory, the Centers for Disease Control and Prevention (CDC) suggests giving them a sponge bath. That reduces the risk of them swallowing water.

Don't Brush Your Teeth With Unboiled Water

Per CDC, don't brush your teeth or gargle with tap water since it's easy to swallow water while brushing your teeth. Using bottled or boiled water is best.

Don't Wash Dishes With Unboiled Water

CDC recommends using disposable plates, cups, and utensils whenever possible during a boil water advisory. If washing dishes is a priority during a boil water advisory, you can use boiled water, added Sims.

CDC also recommends using a bleach water soak for one minute. Use one teaspoon of bleach per gallon of warm water. Let the dishes completely air dry before re-using them.

Also, CDC advises that dishwashers are typically safe if the water is at least 150 degrees Fahrenheit during the final rinse. Or a dishwasher may be safe if it has a sanitizing cycle.

Don't Prepare Food and Drinks or Cook Using Unboiled Water

According to Sims, avoid all water of uncertain quality when you have the potential to ingest it, including in the following instances:

• Drinking beverages made with unboiled water
• Washing, preparing, or cooking food
• Making ice (or using ice that's been made from untreated water)
• Consuming water from a dispenser with unboiled water, like a refrigerator or freezer door or a pitcher filled before the advisory

Don't Clean Surfaces With Unboiled Water

Make sure you clean any washable toys and surfaces with bottled or boiled water or water you disinfect with bleach.

What Can You Do During a Boil Water Advisory?

Bottled water or water you boiled long enough to become safe is best. But there are some cases when you can use untreated tap water, even during an advisory.

However, if your local government issues a "do not use" advisory, don't use tap water for anything, including washing clothes, bathing, and any other uses.

Do Wash Clothes (With Caution)

During a boil water advisory, washing your clothes, as usual, is safe, per CDC.

Do Wash or Sanitize Your Hands

Per CDC, washing your hands in unboiled water might be safe if your advisory doesn't caution against it. Scrub your hands with soap and water for at least 20 seconds. Then, rinse them well under running water. And if soap and water aren't available, use an alcohol-based hand sanitizer containing at least 60% alcohol.

Accidentally Drinking Unboiled Water

"Generally, the chance of becoming ill after accidentally drinking contaminated water is quite low," said Dr. Mony. However, people with chronic illnesses, recent skin infections or wounds, or immunocompromised are at high risk of infection.

"The most frequent signs of an infection after drinking contaminated water are those of the gastrointestinal system," explained Dr. Mony.

Those symptoms include:

• Nausea
• Vomiting
• Diarrhea
• Abdominal cramps
• Fever
• Headache
• Chills
• Muscle aches and pains
• Sore throat

See a healthcare provider if you develop any of those symptoms after drinking potentially contaminated water.

A Quick Review

Your local government might issue a boil water advisory when there's concern over harmful microorganisms in your community's water supply. The advisory means you must boil your water thoroughly to avoid becoming ill.

While the advisory is in effect, avoid drinking unboiled tap water, consuming beverages or ice made with it, and washing your dishes. It's OK to wash your hands with soap and water and bathe if you don't swallow any water and your boil water advisory doesn't caution against it.