Mystery Leak: Need help with detection

[tcpiii]

I've had a leak in my pool for a while, as discussed in this thread. It has been very inconsistent, making it quite difficult to determine the source. It was leaking in the spring, then didn't leak at all for two months, then was leaking somewhat slowly - then last night began leaking at a very fast rate - if it continues for 24 hours, more than 1000gallons/day.

The dye test - with dye or with food coloring in corn syrup - doesn't lead to any evidence around intakes, return, light fixture, ladder, or steps. Nor does there seem to be any evidence around the one noticeable underwater scratch in the liner. Speed of the leak these days seems to be constant, regardless of whether the pump is on or off.

I cannot find any evidence of damp spots down the hill from the pool.

The vinyl liner is 8 years old, and seems in good shape. There is one hole I've noticed above the water line that I've been intending to patch.

As that earlier thread indicates, I have suspected the PVC piping from the bottom drain in the deep end - and at one point thought I had decreased the speed of the leak by putting some plastic over the drain and weighting it down. But I did that again this morning before heading to church, and the rate of water loss did not vary from its rate overnight.

So I am in a quandary, and am anxious to hear some advice.

I presume I need to call in a professional. But, like many of you, I have never used pool professionals since I found poolforum.com and then this site. If any of you would have a suggestion for a professional in the Charlotte or Concord NC areas, I'd be thankful.

 

[citlali]

Newbie to this board, but I was able to detect the leak in my pool.

Mine was from the bottom of the skimmer to the PCB pipe that conects to the bottom of the pool.

Hope this helps.

 

[Bama Rambler]

Does it leak more with the pump running?

Have you inspected the multiport valve waste line to see if it's leaking out there?

 

[tcpiii]

The speed of the leak today does not vary with the pump being on or off.

And, no, there is no leak from the waste port.

 

[Bama Rambler]

Sorry, if I had actually read your post I'd have seen that it doesn't matter whether the pump is running or not.

That leads to a shell leak. Either the liner or a penetration. Though it could be the main drain line. I'd think if that were the leak it would be a little less with the pump running but that would depend on the amount of flow through the MD. If you could pull 100% from the MD you might be able to tell if the leak slowed down when the pump is on.

 

[tcpiii]

OK, I ran the pump for 2 hours only pulling through the main drain. I did lose less water during this time (though the leak was still rapid). I've now opened the side drain and will see if in the next two hours the rate of leakage changes.

 

[tcpiii]

The rate of water loss was exactly the same with the pump pulling through both the side drain and the main drain as it was when pulling only through the main drain.

For the next two hours, we'll test with the pump off.

 

[tcpiii]

I ended up calling American Leak Detection here in Charlotte. I found them very professional. They found one large leak and several smaller leaks in the liner; the pipes checked out fine. I would recommend them to anyone in the area with a similar problem.

 

[waste]

Do you have 1 or more lights in the pool?

The conduit will sometimes break over the winter and cause a leak. When that's the case, we 2 part epoxy putty the niche - it lasts 2 - 5 years, but solves the problem.

Other than the lights, it's a vessel issue (as it doesn't change with the pump on or off).

Please keep us informed as to your progress with this.

 

[Bama Rambler]

Sorry you had to call them but real glad they got you fixed up.