Pool Wall Damage During Winter - Any Advice?

[visitslovenija]

We have an 8x4 pool with a plastic liner. Last autumn the local pool shop advised that I drop the water level to below the lights, (empty all pipes of course) add the winteriser and leave it at that. Which we did.

However, this season I have found that the pool wall behind the liner (concrete blocks with plastic mesh/plaster lining) has been delaminating along the line of the winter water level - still has a tide mark shadow on the liner! In a couple of cases it was so bad we had to drop the water and pull back the liner to repair the wall. Painful watching all that heated water run down the drain.....

My guess is that we had damp or condensation behind the liner at the water level, that then froze and bossed the wall. So it seems like a bad idea. We do get some very cold winters here.

This year I am thinking of emptying the pool completely .

Any advice or thoughts?

Thanks,
Ralph

[donkey-on-the-edge]

I would think very carefully before emptying an in-ground pool completely - we have friends who did just that, and as the water table rose over the winter, it filled the pool from below and pushed the liner up ... it never went back into shape and eventually had to be replaced ...

[Ju]

All advice I have ever read says that for liner pools in particular you should never empty them. As donkey says the risk is that the water seeps in behind the liner and pushes it out. Whilst the pool is full the weight of the water keeps it in place and stops the ground water pushing out the liner.

[Jimbo]

I agree with donkey's and Ju's comments. After our first season when I was a pool rookie, I emptied our pool as winter approached - just seemed logical. Fortunately, our plumber arrived on a job and had a fit when he saw what I'd done. He made me refill the pool immediately to just below the skimmer outlets and tie a line of big plastic containers across the middle (filled with stones to half-submerge them) which relieves the pressure on the pool walls when the water freezes (we regularly get -15C temperatures here). He also insisted that I add 'hivernage' chemicals to the water to inhibit algal growth.

Lots of info about winterising pools on the web.

Jim

[helene]

We used to reduce the level of our pool till it was half full (lots of good reasons including us not being here in the winter and also a built up surround) anyway the inevitable happened and the water level in the surrounding area (a few years ago) was higher than in the pool and so the liner was forced up and we had to try and re-shrink it when we returned home in the spring. We managed it and it seems to have worked but would not want to go through that trauma again - so after that we leave the pool level just under the skimmer. With the benefit of hindsight I would certainly not recommend emptying an in-ground pool with a liner.
Helene

[visitslovenija]

Thanks all for your replies.

Hadn't thought about ground water lifting the liner, so glad to get the advice.

I'll just drop it to skimmer inlet level this year and hope we don't get any more wall problems.

Pools are great for the guests, but a bit of headache to look after really. . .

[Jimbo]

Pools are great for the guests, but a bit of headache to look after really. . .

Tell me about it, Ralph! Much of our time and resources are spent keeping our 12 x 6m pool fit for purpose. Can't do without it unfortunately, but often wish that we could!

Jim

[visitslovenija]

Jim,

With the water left at skimmer level the inlet jets and vacuum point are submerged. Last year, as the water was below them, I used compressed air to blow them through and be sure of no water left to freeze. Do you take any special precautions with yours?

I guess I could drop the water level, blow them out and plug them and then let the water level come back up again?

Tks,
Ralph

[Jimbo]

Ralph, my previous post may have been misleading. We drop the water level to just below the skimmer outlet jets - where the filtered water re-enters the pool (sorry, if I didn't make that clear), remove the water in the pipes and then plug all water inlet/outlet points with things that look like over-sized bath plugs with wing nuts. But our's is a concrete structured tiled pool, not with a separate liner, so that might be significant?

Jim