Raising pool level instead of lowering for winter?

[kmdigital]

I purchased a house with an IG fiberglass pool with an automatic pool cover, so this is my first season closing it. The previous owner always lowered the water level to below the skimmer, but not below the returns as that would be too low for the cover an overstress it and the tracks.

The problem with lowering the water level is that the cover will hold several thousands of gallons of water, and in my experience, whenever there's water on the cover, it raises the level inside the pool an equal amount, at least around the edges. Therefore, if the water doesn't get pumped off, the water on the cover will fill to the top of the pool, and then run off, while the water inside the pool will fill all the way to the top as well.

The problem is that I will be AZ for 3 months this winter, and won't be able to put a pump on the cover to pump it off. It may or may not be needed in Jan and Feb, but I'm sure it will in Mar before I get back. Rather than have to worry about it, I'm wondering if it would be reasonable to winterize with the water level way high? I can blow and plug the returns, use a Gizmo in the skimmer, us an empty bleach bottle jammed in the skimmer opening to raise the skimmer flapper and protect it, and jam extra foam inside the skimmer to provide additional freeze protection for the skimmer.

Given that I expect the water level in the pool to come up to the top edge anyway in the winter with rain and melting snow, it seems like it would be a good idea to instead raise the water level way up to start with. This way the cover will hold much less water and it won't be as critical to pump it off whenever the snow melts, etc.

Another consideration is that the pool is about 2-1/2" - 3" out of level, end to end. The lowest point is on the shallow end where the returns are, and if the water runs off the cover (or overflows the pool) here it will just run off the concrete into the gravel landscaping. This means that the water level at the skimmer end is always several inches below the other end of the pool, and it can't fill up completely at this end. This is another reason for not being able to lower the water level below the returns, as they are considerably deeper than they probably should be, and lowering the water this far would really strain the cover, particularly at the deep end.

I don't know how thick the ice will get on top of the pool, but that depends on how cold it gets, and my assumption is that probably 6" - 12" if it's like a pond or lake. It would seem to be better for the return plugs to have them well below the surface of the water, and this way they might not freeze into the ice, which would seem to be better than having them just below the surface.

What are your thoughts? Does this make sense, or should I lower the water like most people do when winterizing?

 

[toofast]

I have a fiberglass pool as well, and my PB does not recommend lowering down below the returns. He said just lower slightly above the very bottom of the tile. Reason is that he does not want the ICE to build up on the bottom edge of the tile and pop it off.

If you go too high, you could pressure the coping (if it hangs over).

Honestly, I am torn...PB tells me that since the tile was put on with a "adhesive" vs. hard epoxy - they will MOVE a bit with the ice pushing, but much better than the ice grabbing the edge.

I will have a mesh cover, and my returns are way more than the 14" - 16" slack that is recommended.

Hopefully experts will chime in...but you have my $.02 if it helps.

 

[kmdigital]

Since I don't have tile around the edge, my thoughts are that having it higher doesn't really matter, as long as I protect the skimmer. I don't know how deep the concrete is below the pools edge, but it seems to me that it would actually be better for the fiberglass to have it freeze higher, in line with the concrete where it can't move, rather than deeper where the pressure of the ice may be pushing against dirt. This would put pressure on and probably flex the fiberglass below the concrete, stressing it and potentially causing stress fractures in the gelcoat if nothing else. Of course, there may be other things I'm not considering, hence the questions here..

The assumption here is that the concrete around the edges is poured right up to the back side of the fiberglass, but not having seen it installed, maybe that's not the way it works. There's about a 3" lip on the fiberglass that's embedded in the concrete, and level with it, and the assumption is that the concrete goes under the lip and is poured right up to the side of the pool.

 

[toofast]

So if I remember...the collar goes down perhaps 12" or so, and at least in mine it did go against the outside edge of the pool.

The big issue, is just make sure the ice does not push against your coping, and I think you should be fine. (as you said, protect the skimmer)