Chapter 20
Is the tap water safe after a flood?
The questionIs it safe to drink the water from my tap now that the flood has gone down?
The short answerTap water after a flood is safe to drink only when your water system says so: on city or district water, follow its notice and TCEQ's rules; on a private well, wait for disinfection and a clear lab test.
By the editors of High Water at Home · Updated · about 7 minutes
Sections in this chapter
- 20.1 Who decides whether your tap water is safe?
- 20.2 What kinds of water notice can you get?
- 20.3 How long do you boil, and what else changes?
- 20.4 How is a boil-water notice lifted, and how will you hear?
- 20.5 What should you flush once the notice is lifted?
- 20.6 What about the water heater?
- 20.7 What if your water comes from a private well?
20.1 Who decides whether your tap water is safe?
On public water, your utility does, under state rules. Texas public water systems answer to the Texas Commission on Environmental Quality. TCEQ's page on boil water notices, last modified 22 Jan 2026, says a system must issue one when pressure falls below 20 pounds per square inch, when disinfectant levels drop too low, or for other triggers such as an E. coli violation. The notice must go out as soon as possible and within 24 hours.
Floods can bring on those conditions. FEMA's 2017 utility guide says contamination risk is greatest when system pressure is lost, which is why suppliers routinely issue boil orders afterward. In the City of Wharton, the water comes from city wells in the Chicot aquifer (public water system TX2410005). El Campo runs its own system, and so do rural districts and subdivision systems in the county, such as the Wharton Boling MWD that appears on TCEQ's 2021 freeze list. Each sends its own notices.
If your water comes from your own well, none of this applies to you. Skip to the last section.
20.2 What kinds of water notice can you get?
CDC describes three kinds of drinking water advisory, and they mean different things. Table 20.1 shows the difference.
| Advisory | What it means | Does boiling help? |
|---|---|---|
| Boil water | Germs may be in the water | Yes, at a rolling boil for the time on the notice |
| Do not drink | Something in the water boiling will not fix | No; use bottled water |
| Do not use | The tap water is not to be used for anything | No; use bottled water for everything |
CDC states that boiling water that holds harmful chemicals or toxins will not make it safe. So read the notice's first line carefully. If it says do not drink, boiling is not an answer.
20.3 How long do you boil, and what else changes?
Follow the time printed on your system's notice. CDC's minimum is a full rolling boil for 1 minute below 6,500 feet. TCEQ's customer guidance, and Texas notice wording, uses 2 minutes. Both agencies say to boil even water that has been through a home filter or filter pitcher.
During a notice, CDC and TCEQ list a few habits to change:
- Skip the ice maker and the refrigerator's water and ice dispensers.
- Brush teeth with boiled or bottled water.
- Run the dishwasher only if it has a sanitizing cycle or reaches a final rinse of at least 150°F, as CDC puts it.
- For hand-washed dishes, CDC and TCEQ give a soak of 1 teaspoon of unscented bleach per gallon of warm water for at least 1 minute.
- Tap water is fine for houseplants and gardens, CDC says.
20.4 How is a boil-water notice lifted, and how will you hear?
A system cannot just announce that it is over. Under TCEQ's rules, as its page read on 11 Nov 2026, the problem must be fixed, the lines flushed until disinfectant is back to normal, and special bacteria samples must come back negative for coliform. The lift notice goes out the same way the original did.
In Wharton, the city sends mass messages through Smart911 and posts press releases on its site; during the February 2021 freeze it used releases to ask people to save water and keep pressure up. TCEQ's 2021 list shows El Campo's freeze notice lifted on 20 Feb 2021. Sign up for your own system's alerts before storm season. Boil-water notices in Wharton County has more on how each notice works.
20.5 What should you flush once the notice is lifted?
Your own pipes, because the water standing in them came in during the problem. CDC's 2016 advisory toolbox gives utilities a checklist to hand customers. It leaves the number of minutes blank for each utility to fill in, so use the time on your system's lift notice.
- Run cold and hot water at every faucet, starting with the highest one in the house.
- Run the refrigerator's water line, throw out the ice it makes in the first two batches, and change its filter.
- Change any whole-house or under-sink filter cartridges, as the toolbox says.
- If the water is discolored, wait to do laundry until it runs clear, then wash a dark load first.
A strong chlorine smell after a lift is usually the extra chlorine the system used to clean its pipes, CDC notes. Wharton's own February 2024 release on a new city well gave similar advice for rusty water: run cold taps a few minutes until clear and hold off on laundry. Softeners and treatment units have their own steps in Softeners, filters and treatment units after a flood.
20.6 What about the water heater?
If it sat in floodwater, do not use it at all; that is covered in Water heaters that went under water. If it stayed dry, its tank is still full of water that came in during the notice. CDC's facility checklist includes flushing hot water tanks, and a licensed plumber or the heater's manual can tell you how for your model.
Houses left empty after an evacuation have one more risk. Rheem's gas water heater manual warns that hydrogen gas can build up in a hot water system unused for about two weeks or more. The maker's advice is to open a hot water faucet, such as the kitchen sink, for several minutes before using anything else, with no smoking or open flame nearby.
20.7 What if your water comes from a private well?
Then no notice will come, and the decision is yours and the lab's. CDC's reentry guidance says that if you have a private well in a flooded area, get the water tested before you use it. Do not drink it, cook with it or brush teeth with it until the well is disinfected and an accredited lab reports it clean.
Use bottled water, or water boiled for at least 1 minute, until then. Disinfecting a flooded well and Testing well water after a flood walk through both steps.
Questions readers ask
Can the baby's formula be made with boiled tap water during a notice?
CDC lists making baby formula among the uses to avoid with water you suspect is contaminated. Use bottled water, or follow your doctor's and your utility's directions, until the notice is lifted.
The notice was lifted but the water tastes of chlorine. Should it be avoided?
Usually not. CDC notes that systems often raise chlorine levels to disinfect their pipes after an advisory. If it bothers you, ask your utility how long to run the cold tap.
Is shower water safe during a boil-water notice?
Read your notice; it usually says. TCEQ suggests a sponge bath for babies during a boil notice, and a do-not-use advisory means the water is not for any use at all, bathing included.
Does a flood mean my water line from the meter needs replacing?
Not by itself. If you see pressure loss, wet ground or a running meter with everything shut, call your water department first. Who fixes which pipe covers the owner's side of the meter.
Can pets drink tap water during a boil notice?
CDC advises giving pets bottled water or boiled water that has cooled. The same rule as for people keeps it simple.
What this chapter rests on
This chapter leans on TCEQ's boil water notice page, CDC's advisory overview, reentry page and 2016 advisory toolbox, FEMA's utility guide, Rheem's gas water heater manual and City of Wharton pages, all checked on 11 Nov 2026, plus TCEQ's 2021 list of lifted freeze notices. CDC leaves flushing times to each utility, so no minute count appears here. How El Campo sends notices today was not posted on a current city page as of 11 Nov 2026; check with the City of El Campo directly.
Notes to chapter 20
- TCEQ — Understanding Boil Water Notices · triggers, 24-hour rule, 2-minute boil, how notices are lifted, ice, dishes · checked 11 Nov 2026
- CDC — Drinking Water Advisories: An Overview · three kinds of advisory, 1-minute boil, filters, dishwashers, chemicals, plants and pets · checked 11 Nov 2026
- CDC — Drinking Water Advisory Communication Toolbox (2016) · flushing taps from the highest faucet, ice, filters, discolored water, chlorine smell, hot water tanks · checked 11 Nov 2026
- CDC — Reentering Your Flooded Home · test private well water before use, formula · checked 11 Nov 2026
- FEMA — P-348, Protecting Building Utility Systems From Flood Damage (2017) · pressure loss and boil orders · checked 11 Nov 2026
- City of Wharton — 2025 Consumer Confidence Report · Chicot aquifer, system TX2410005 · checked 11 Nov 2026
- City of Wharton — Smart911 · city mass messages · checked 11 Nov 2026
- City of Wharton — Conserve Water Press Release, 18 Feb 2021 · how the city announced water problems in 2021 · checked 11 Nov 2026
- City of Wharton — New Water Well release, 19 Feb 2024 · run cold taps until clear, hold laundry · checked 11 Nov 2026
- TCEQ — Public Water Systems with Lifted Boil Water Notices, 2021 · El Campo notice lifted 20 Feb 2021 · checked 11 Nov 2026
- Rheem — Gas Water Heater Use & Care Manual AP21831 · hydrogen in unused hot water systems · checked 11 Nov 2026