What to do on a under slab leak?

We have an under the slab leak more than likely from pipe freeze this Winter. I don't think the leak goes that far underneath the slab.

Is it possible to fix such leaks without having to use a jackhammer to go through the slab? Or does the slab actually cover the pipe up from when they originally poured the cement foundation?

Has anyone actually done some digging underneath a slab to fix a leak or is that even possible?

This sounds like a slab on grade situation. Is that the situation? What makes you think you have a supply line leak? A picture or two would also be helpful.

We are in Texas where s-o-g is commonly used so yes. As for a picture, there's nothing to photograph yet since there's nothing to show with all the leaking occurring under the house soon as we cut the main water line on at the meter.

What happens is we cut the main water line on and the leak begins pouring out under the slab coming out from under the concrete in the back of our house. We wash dishes, clothes, baths, etc then go to cut the water off when done and the leak stops until next time.

The only options we seem to have are:
1. Jackhammer through the concrete to fix which is probably about 6-8 inches of slab in this particular area of the house
2. Dig under the slab where the leak is pouring out to see the exact problem
3. Fix all plumbing to go above the slab

I'd like to try #2 first but thought someone would know something about under the slab plumbing before attempting it.

I believe by hiring a leak detection service, they will be able to pin point the location of the leak. With this information, you can decide if it is worth your time to dig out or replace the line in its entirety.

If water is flowing out from under the slab you should be able to follow it back to the leak and if the leak is more than a couple feet back it will be easier to break out the concrete to get to it. If you can not follow it or know exactly where it is I would go the leak detection route to at least pin point it then start hammering from there.


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Thanks for the tips here, you guys. I think I will take your advice, Chris since from examining the way the leak is pouring out from under the slab seems to be within the first foot or two from the edge of the slab (more than likely from the freeze since this struck in freezing cold weather.)

I'd hire a leak detector but truthfully, they'd basically be telling me the leak is in an area where I already know it to be.

The bad thing about the digging is it's in an area where a lot of tree roots are underground in which has already broken one shovel.

.... more later....