Water Heater Leak: What to Do Right Now

Reviewed by Tyler Bennett, Restoration Project Manager, IICRC WRT/ASD #291438, October 2026.

Short answer: If your water heater is leaking, shut off the cold water valve at the top of the tank, then turn off the breaker or set the gas to off or pilot. Stay clear of hot water, photograph the damage and check nearby walls and carpet for water you cannot see.

If the tank has already flooded your floor, our round-the-clock water response team in Spanish Fork can start extraction and drying right away.

Step 1: Shut off the cold water supply

Every tank water heater has a cold water inlet pipe at the top. Most have a valve on that line. Turn it off to stop more water from filling the tank.

If that valve is stuck or the leak is bad, shut off the main water valve to the house.

Step 2: Cut the power or gas

Electric heater: Turn off its breaker at the panel. Only do this if you can reach the panel from a dry spot.
Gas heater: Turn the gas control to off or pilot. If you smell gas, leave the house and call the gas company from outside.

Running a heater with no water coming in can damage it. Cutting power also lowers your shock risk around the puddle.

Step 3: Be careful with hot water

Water in the tank can be hot enough to burn. Give it time to cool before you drain it or touch fittings.

If you need to drain the tank, attach a hose to the drain valve near the bottom and run it to a floor drain or outside. Open a hot water faucet upstairs so air can enter the tank.

Step 4: Find where the water came from

Not every puddle means the tank is done. Here are common sources:

Where the water is	Likely cause
Top of the tank	Loose inlet or outlet fitting, or a leaking valve.
Pipe on the side	The pressure relief valve is releasing or has failed.
Bottom of the tank	Drain valve leak, or a rusted tank that has failed.
Under the tank, slowly spreading	Often a tank failure. It will not fix itself.

A plumber can tell you if the heater can be repaired or needs replacing. Our job is the water that got out. We handle that across Utah County.

Step 5: Check where the water went

Water heaters often sit in basements, closets or garages. Water runs across the floor and under walls before anyone sees it.

Look at the base of nearby walls for dark lines or swelling.
Press on carpet in nearby rooms. Wet pad feels squishy.
Check storage boxes on the floor.
Smell for a musty odor in the days after.

Take photos of everything before you clean up. Then call your insurer. Most policies ask you to report a loss promptly. Check your policy for details.

Is the water clean?

Water straight from the tank is usually Category 1 (clean) under IICRC S500. But it can pick up rust and sediment. If it soaks into carpet or sits for a day or two, it can degrade toward Category 2 (gray).

That matters, because carpet pad is usually replaced after Category 2 water. Drying fast keeps more of your home savable.

What we do on a water heater job

We start with a moisture map using pin and pinless meters and a FLIR thermal camera. That shows us how far the water spread.

Then we extract standing water, set air movers and LGR dehumidifiers and check moisture every day. Most structural drying takes 3–5 days.

If drywall or flooring needs to come out, the same crew rebuilds it. Our water heater cleanup service page has more on the process.

Water mitigation usually runs $3,500–$8,500, and a typical dry-out is about $4,500. We give free written estimates and bill insurance directly.

Water heaters often share a basement with a sump pump. If yours sits in a basement that floods, our basement water cleanup team handles that too.

Common questions

Can a leaking water heater flood my house?

Yes. A failed tank can keep releasing water as long as the cold supply is on. That is why shutting off the supply valve is the first step.

Is it safe to use hot water after a leak?

Not until a plumber checks the heater. If the tank has failed, it needs to be repaired or replaced first.

Does insurance cover water heater damage?

Many policies cover sudden water damage from a failed tank but not the heater itself or slow leaks. Check your policy and talk to your agent.

Will I get mold from a water heater leak?

Mold can start in 24–48 hours in wet materials. Drying fast and confirming it with meters is the best way to prevent it.

How fast can you come out?

We guarantee 45-minute arrival inside Spanish Fork city limits. In Springville, Mapleton, Payson, Salem and Saratoga Springs we are typically there in under 60 minutes.