Water seeping up through the floor, the garage slab, or the grout lines? Shut off the main water valve if you can. Then call or send a few details, and a local slab leak plumber will get back to you.
Do this first
Find the main shutoff and turn it off. It’s often in the garage, near the water heater, or in a box near the street. If you can’t find it or it won’t budge, the valve at the water meter will stop the water too.
Then watch. If the water stops coming up after the main is off, it’s almost certainly a pressurized water line under the slab. That’s a slab leak, and it needs a plumber.
Move rugs and furniture off the wet area, and take photos before anything gets cleaned up. If you’re going to file an insurance claim, you’ll want them.
If it keeps coming after the water’s off
Then it’s probably not your supply line. The usual suspects are a broken drain line under the slab, which shows up mostly after someone runs water or flushes, or groundwater pushing up after heavy rain.
A drain leak is still a plumbing job. See sewer and drain under the slab.
Groundwater is not. If water only shows up after storms, especially in the garage or along an outside wall, the problem is usually drainage around the house, like grading, gutters, or a low spot that holds water against the foundation. A plumber can rule out a leak, but the fix is outside.
In the garage
Water coming up through a garage floor can be any of the three. Check whether it lines up with a water line, like the one feeding a water heater or a laundry room on the other side of the wall. A moving meter with everything off points to a leak. See how to check your water meter.
Don’t wait on it
Water under a slab doesn’t dry out on its own. It soaks the soil under the foundation and the floors on top of it, and every day adds to the water bill. Get it looked at.
Water coming up through the floor? Call now.