What Harvey Taught Friendswood About Flooded Water Heaters
Hurricane Harvey dropped more than 50 inches of rain on Friendswood between August 25 and 29, 2017. When the water finally receded, we replaced hundreds of water heaters over the following year. Not all of them failed the first week. Some failed 8 months later, quietly, from slow-onset corrosion.
The Non-Negotiable Rule: A Submerged Gas Heater Must Be Replaced
FEMA guidance, every gas water heater manufacturer, and the National Fire Protection Association all say the same thing: if the burner assembly, gas valve, or electronic control was under floodwater, that unit cannot be certified safe.
Electric Heaters: Same Rule
An electric water heater whose thermostat or heating element enclosure has been submerged should be replaced. The element seals corrode. The thermostats fail.
The Slow-Onset Failure Pattern
The reason we were still replacing Harvey-damaged heaters in April 2018 is that some heaters kept operating for months before an interior component finally rotted through. Symptoms started as odd noises, occasional pilot outages, or rusty water.
Insurance and Documentation
Standard homeowner insurance does not cover storm surge or rising-water flood damage. That requires flood insurance. Document with a photo of the unit with high-water mark visible, model and serial numbers, a written scope from a licensed plumber, and the receipt for the replacement.
The Post-Storm Timeline That Actually Fails Water Heaters
Most Friendswood homeowners who lost a water heater to Harvey did not lose it during the flood itself — they lost it in the six to twelve months afterward, quietly, as slow-onset corrosion attacked internal components that had briefly touched floodwater. The gas valve was the most common failure point, often preceded by intermittent pilot outages and finally a total no-heat call. By then the eight-month gap made the connection back to the storm easy to miss, and the homeowner paid full price for a "surprise" replacement.
What to Do in the First 72 Hours After Any Gulf Storm
Do not relight a gas water heater until a licensed plumber has confirmed the burner assembly, gas valve, and control board did not touch floodwater. Do not turn power back on to an electric heater whose element enclosures were submerged. Even if the exterior of the tank looks dry, we can pull the burner cover and inspect for water residue in about twenty minutes. If the unit passes, you get written documentation for your insurance file. If it fails, we replace under permit and can usually help you document the loss for a flood claim.
Elevation Options for the Next Storm
For any Friendswood home south of FM 518 or in a known low-lying pocket, we recommend elevating the water heater onto a code-compliant platform before the next hurricane season. Where garage or attic constraints prevent full elevation, we install a raised drip pan with a piped drain and seismic-style straps as an intermediate measure. Both options are documented in writing and often qualify for reduced flood insurance premiums when you can show mitigation on file.
Coordinating Insurance, Plumber, and Restoration
Post-Harvey we learned that the single biggest source of delayed insurance payouts was disorganized documentation — homeowners had a plumber invoice, a mitigation invoice, and a rebuild estimate that used slightly different language and dates. When we do a flood-damaged water heater replacement now, our written scope explicitly cross-references your restoration company's work order and your insurance claim number. That single formatting choice cuts adjuster follow-up questions by more than half and typically shortens payout by two to three weeks.