Leak theory

[rimshaker]

Over the past 2-3 years i noticed my pool slowly leaks only during winter months; almost 2 inches a week. Live in FL so it doesnt ice up but can get very cold nonetheless. But as it warms up during spring/summer the water level is totally stable. I don't think evaporation can explain this so i have a theory, and hope any one here can support or refute this.

I think ther may be a hairline crack(s) somewhere. When temps get very cold, the pool lining material below ground is contracting, literally opening and widening this crack. But as the weather and water get hot, the lining material is all expanding, essentially pushing and closing up the hairline crack and voila... no more leaking.

If bridges and roads expand/contract, pool surfaces surely do also right? If this theory is even remotely true.. how in the world do i locate small cracks like this to permanently patch it up? Was totally resurfaced with Pebbletec about 5 years ago.

 

[PoolGuyNJ]

Get some dye pens than try a couple drops around the seams at the skimmers and it's drain ports, returns, the light niches and drain pots, and any hydrostatic relief valves, If you have dive equipment, its easier to get the the hydrostatics and drain pots.

Temperature will definitely cause expansion and contraction but it isn't a lot.

Have you tried to see how far it would go?

Have you pressure tested the lines?

Scott

 

[duraleigh]

Do you operate your pump and filter in the winter as you do in the summer?

 

[carolina pool]

Your theory isn't that far off although I would be more inclined to think it was expansion and contraction of the underlyiing soil from a change in moisture levels. I can think of 3 instances where pools lost water on a seasonal basis. Two were large commercial pools built in flood plains and had center bulb waterstops that failed in the winter but sealed in the summer. The other was a very large residential fiberglass wall, concrete bottom that had a very narrow breakover point between a large deep end and large shallow end. Every year the visible crack would open up in the late fall and close in the early spring.

If you can find the crack, you can cut it out and put in an appropriate flexible mastic and maybe solve the problem.

 

[rimshaker]

Thanks for the suggestions. Guess i will have to research this a little further. I do run the pumps during winter months, but only 1 or 2 days a week, just so things dont get stagnant. I've used dye drops to test the skimmer, returns, and footsteps. I've let it drop below the tile levels, so im thinking the plaster is cracked somewhere *sigh* its a fairly big pool

Now that the weather and water have warmed up a bit, I already notice the leakage has slowed considerably.