Tapped on ice, liner split.

[alben]

I did something really stupid today, and had no idea that the result of my actions would be so catastrophic. It has been rather cold the past week in Minnesota and my family and I were curious how much ice would be on top of our pool. So I unhooked a few of the safety cover straps to get a good look of the ice in the pool. The ice was crystal clear. I did notice that the water level was rather low as when I had the pool closed in October, the water level was just below the return jets, but now the water level was about 15" below the jets (red flag). So I proceeded to tap on the ice about 15" from the edge with the metal tool used to snap on the safety cover. I am tapping away to see if I could punch through the ice. Imagine my surprise when I actually witnessed the vinyl liner on the BOTTOM of the pool split and a wide crack develop. The split is a semicircle of about 5 feet in length. #*&%@#!

So, it is obvious that tapping on the ice did this, as I saw the split occur right before my eyes. Does tapping on the ice cause a pressure shock so large that it can split the liner below? Or is it due to the liner being cold (32 deg)? The ice was 1" thick and there was about another 24" of water under it. The liner is 10 years old and the normal water depth of the entire pool is 4'8"

So NOW what? I assume the rest of the water is going to drain out. The pool was winterized, but what is going to happen to the main drain? What about ground heaves from no water in the pool? We have not had any snowfall yet, but I am assuming that snowfall on the safety cover is going to be a huge problem without ice for it to rest on.

Gosh, I feel like such an idiot...

 

[Pool Clown]

Don't beat yourself up for that.
Since the water level was lower than you left it before you tapped on the ice, your liner was probably already ruined from a rupture elsewhere.

 

[JohnT]

Ouch!

Are you sure it's not a crack in the ice that is distorting your view of the liner?

If it is the liner, at that age, your liner was probably close to shot anyway.

Your main concern is going to be the stability of the pool walls. They aren't designed to handle wind loads with no water. If the pool starts losing water, you'll need to get the cover off since it can't handle not having any water below it. You will probably need to come up some kind of frame to block up the pool walls.

 

[alben]

I know it is not a distortion, as you can actually see air bubbles rising from the crack and the liner is starting to float. I stuck a wooden handle down the hole in the ice and sure enough, the liner is floating. I just called my pool service man, and he doesn't seem overly concerned about the pool, as "there really isn't much that can be done now." I asked if the ground frost is going to heave the pool walls. He has seen pools that were empty by springtime due to a hole in the liner, and the pool walls appeared to stay intact. One thing in my favor is that this is a "Sport Pool", where there is no deep end. The walls are 3' 6" high and then the bottom dishes down to 4" 6". It is a sand bottom.

Yeah as to liner life, my pool service guy said that 8-12 years of liner life is typical in Minnesota. The previous owners of the house went through a couple of liners at the 10 year mark each.

 

[JohnT]

He's probably right. I misread " oval in-ground" in your sig as "above ground" when I glanced at it. You still might have issues with your cover, since a heavy snow load with no water under the cover can cause the cover to fail.

 

[reindeerboy]

What I have done here in ND is put a tractor tire inner tube in the middle of the pool. That way the ice compresses the tube and is easier on the liner come spring. I think it works well plus gives my mesh meyco cover a little support. This winter has been great so far. No snow considering last year we had 2 feet on the ground already. Its 54 outside right now! Record high temp was set today! Walked outside with just a teashirt on with a cup of coffee, sunglasses, and a beatiful winter day! Life is good!

Sorry to hear about your liner, but maybe after you get it replaced, try putting that tire innertube in. I think it helps anyway. My liner is 8 years old and is in great shape. I hope to get 12-15 out of it.

Merry Christmas everyone!

 

[alben]

Excellent tip on the tractor tire inner tube. Isn't the inner tube mostly out of the water, with only an inch or so actually submerged, and consequently frozen into the ice? It does seem like an excellent way of supporting the safety cover.

I thought my liner was in decent shape, as there were no holes or tears. I actually attribute the relatively good condition of my 10 year old line based on that we keep our safety cover on at all times, even in the summer, except when we are actually using the pool. We do this for child/pet safety reasons, keeping leaves/debris out, and keeping sunlight off the exposed part of the liner (above the water line).

Yeah, it was a beautiful winter day. It was 51 degrees here, with full sun shining, and no breeze. We certainly have had a nice fall/winter so far. Moderate temperatures and no snow.

 

[reindeerboy]

Yep. Tire is in a few inches and gets frozen in place which helps when it thaws and refrezes again. Puts more pressure on the inner tube and not your side walls and gives you the added feature of support for you mesh cover.

I leave mine off in the summer, but use a solar cover on it when I am not using it. Works great. If you wish, take a look at my pool in my signature. Has a few more pics and gives you an idea of what my liner looks like. At least I am happy thus far.

Good luck with your liner Man! Wish you the best in getting it fixed next spring. If I had to do it again, I would use a commercial grade 30mil liner. Thats my plan for the replacement liner in a few years for my pool but am hoping to get another 5-8 years out of this one I hope.

Merry Christmas and Happy New Year to you and your family man!

 

[PoolGuyNJ]

When vinyl gets cold, it loses plasticity. It also shrinks. These things also happen as liners age. Put it all together and what happened happens. Can't change it till you have 60 degrees or better for setting the liner.

Scott