Return Line Leak Discovered During Closing

[BTMahoney]

I recently had my in-ground concrete pool closed and during the process the technician discovered a leak in the return lines. When he pressurized the return lines, air and water came up from under ground about 3 feet from the edge of the concrete decking (which is 4ft wide). When I got home I could clearly see the spot where the air/water had escaped. Oddly, there are no pipes running adjacent to that spot (I got to see the plumbing when the pool was built 3 years ago). Also strange is that I observed no indication of a leak in the system before I drained the water down and had the pool closed.

Has anyone had a situation like this?

Is it normal for the air/water to escape the ground so far away from the source of the leak?

Could the process of lowering the water (below the return line) and pressurizing the line CAUSE the leak or expose the existence of a leak?

I believe the leak is under the concrete decking - what should I do now?

 

[duraleigh]

Are you losing water?

 

[BTMahoney]

I didn't notice any water loss before the technician came and closed the pool. Now the water level is below the returns and appears stable.

 

[duraleigh]

Is the pool closed? If so, I think I would leave it alone until Spring if the water level is now stable.

Address the leak (which is very unusual) when you reopen and fill the pool back to normal. I am not clear what the pool guy could have done to cause the leak, if it is in your return pipes. Again, your circumstance is very unusual and I don't think you can find it without the pool back at normal levels.

 

[BTMahoney]

Following up on this thread...

I had my original pool builder open the pool and they confirmed the leak and the same behavior. Water was flowing up from the ground about 3 feet from the edge of the decking. It made about a 6 inch high fountain when the return lines were in use. In addition - muddy water would flow into the pool from one return line. The pool company thought the leak was a return line near the edge of the decking and I looked at some photographs from when the pool was built and they confirmed the return line did run near the location.

NOTE - If you are building a pool - take copious pictures of the plumbing before the trenches are backfilled!!!

After the pool was opened I went ahead and dug the ground up where the leak released into the yard. I was able to follow the source of the water to the edge of the concrete and then dug down and was able to locate the pipe. I could only reach down and feel the pipe as the hole would fill with muddy water to match the level of the pool. Turns out there is about a 2-3mm crack that goes around about half the circumference of the pipe. The crack is right next to a coupling where the pipe turns about 40 degrees or so.

Is this crack likely to be from the initial installation or could it be from freeze damage? Is there any way to know? It doesn't really matter - the same company that built the pool closed it, and they are going to repair it at no cost to me - but I'm curious to know the likely source.

Is it unusual for a crack like I describe to not result in a lot of water loss? Only after the return lines were pressurized and the leak fully revealed did I notice water loss.