Boil Water Notice: What is a Water Boil Advisory?

Every year in winter, there is a spate of boil water notices in Texas. More extreme winter storms are likely to bring widespread boil water advisories to Texas in the future.

Why? What causes a boil water notice and how important are they?

What is a Boil Water Notice?

Health departments issue a boil water notice – also called a boil water advisory or boil water order – whenever drinking water is, or may be, contaminated.

Many things can cause a boil water advisory, including:

• Routine water sampling comes back positive for a contaminant.
• A water main breaks, introducing potential contaminants.
• The widespread loss of system pressure, which allows contamination from groundwater.
• The water treatment facilities have a problem that prevents complete decontamination.
• Flooding, severe weather, or other natural disasters cause potential contamination.

Usually, the boil water notice will mention whether the order is the result of a confirmed contaminant or whether it's precautionary.

Even if it's precautionary and the problem is repaired quickly, officials can't lift the boil water advisory until they get a negative test confirming that the water is safe to drink. This can take 24-48 hours.

Why Do Winter Storms Bring Boil Water Notices to Texas and the South?

In the north, water infrastructure is designed to withstand a freeze. That's not the case in warmer states. As a result, when a freeze hits a warm state, a few things can go wrong.

In warm states, it's common practice to leave water running so that household pipes don't burst. When enough people do this, even in small amounts, it can lower system pressure. When the pressure in the system drops, groundwater can start to seep in through small cracks, bringing bacteria and other contaminants.

Not running water can lead to burst pipes, or water mains themselves can burst due to freezing. The resulting leaks can lower the system pressure, resulting in groundwater seepage.

Power outages can create water flow issues when power stops supplying water pumps. When the pumps stop working, buildings are fed by gravity from nearby water towers or reservoirs until they're empty. As the pipes empty…seepage.

Finally, a massive power outage can hit a water treatment facility, causing water decontamination to stop entirely. This leads to potential contamination for everyone served by that facility.

What Happens If You Drink Water Under A Boil Advisory?

Healthy adults often won't have problems, but don't take that to mean you can ignore the order.

At-risk populations will be more sensitive to waterborne diseases, including young children, the elderly, and the immunocompromised. They don't need to consume nearly as much of a pathogen before it makes them sick.

However, even someone in peak health can become very sick under the wrong conditions. Drinking contaminated water can lead to diarrhea, cholera, Giardia, Salmonella, E. Coli, and more. It could lead to hospitalization, death, or long-term health issues.

What to Do During a Boil Water Order

There are some things that are perfectly safe to do without boiling water, and other things that absolutely require you to either use bottled or boiled water.

Boil Water Before Consumption

When you're using water on anything that you'll consume, you need to either use bottled water or boil tap water for at least 2 minutes and then let it cool. This will kill any pathogens that might make you sick.

This covers more activities than you might consider at first, including:

• Drinking water or using it to prepare drinks
• Using water for cooking or for washing raw foods
• Brushing your teeth
• Making ice (freezing will NOT kill the pathogens)
• Providing water for pets

If you made any ice after the boil water advisory was issued, throw it away. You also can't use water or ice from any appliance directly connected to your water line (like the refrigerator).

Filtered tap water remains unsafe. It must be boiled before consumption.

If you need to water your plants, unboiled tap water will be perfectly safe for them. Just make sure pets and children can't access it.

Use Caution for Washing Dishes and Bathing

During a boil water order, using unboiled tap water for showering or washing dishes depends on a few things.

If you have a dishwasher, it's generally safe to use it during a boil water advisory. Just make sure the water in the final rinse reaches at least 150 degrees. This may require using a sanitizing cycle.

Always sanitize baby bottles during a boil water notice.

If you have to handwash your dishes, wash and rinse them as normal, but follow up with extra precautions. Place your cleaned dishes in a basin of bleach water (1 teaspoon of household liquid bleach per gallon of warm water). Soak the dishes for at least one minute, then rinse them in previously-boiled water. Allow dishes to air dry.

Precautions should also be taken when washing anything that might go in someone's mouth, like baby toys.

Generally speaking, unboiled tap water is safe for showering and washing your hands as a healthy adult. However, you'll want to make sure you have no scratches or open wounds, and you should avoid getting water in your mouth, nose, or eyes. Avoid simply rinsing your hands – use soap for 20 seconds, or follow up your hand washing with alcohol-based hand sanitizer.

Anyone who is more susceptible to infection should take a cautious sponge bath instead of subjecting themselves to unboiled tap water. This includes babies, young children, the elderly, and the immunocompromised, or even healthy adults that have an open wound.

It's safe to do laundry as usual.

What To Do After A Boil Water Advisory Is Lifted

Your local health department will tell you when the boil water notice is lifted, but you need to do a few things to ensure it's safe to go back to normal:

• Flush your plumbing by running cold water from all faucets for at least 5 minutes apiece.
• Flush appliances connected to a water line, like refrigerators or water fountains.
• Flush ice makers by making and discarding three batches of ice.
• Discard any water filters that came into contact with contaminated water.
• Run water softener systems through a regeneration cycle.

If you have any "food contact" surfaces that were exposed to unsafe water, cross-contamination is a risk, so you'll want to disinfect them as well.

Now that you understand how to keep your household safe during a boil water order, check out our related article on how to plan for food safety during a power outage.