Pool Depth Clarification for Winterization (50 year old vinyl lined inground pool)

[StillSyeina]

Hi all,

I'm looking for some advice with respect to pool winterization for my old inground pool. We use a solid cover, so no rain water will be getting in during the cold season. The area is also very dry if that is a concern or interest.

I drained below the returns and had the pool company blow it out and seal the lines, as well as put antifreeze in them. Should I be raising the water level again over the returns afterwards or would this cause ice damage to the returns when it freezes? Mine are pretty close to the bottom as it is an older inground pool and it got down to -30 here last winter. Of course, I'm also concerned leaving the water level too low could lead to a damaged liner.

We moved in last year with the pool already closed and I seem to recall the pool water level being about 6 inches higher last year compared to what the pool company told me to drain it to, but I don't trust my memory with respect to that because that had much less significance to me last year.

That, and I've come across some conflicting information googling it and would really rather not damage my pool.

Thank you for your time!

 

[sande005]

Are the returns sealed with plugs on the pool side? If so, no harm will happen if they end up under water. The liner won't care about frozen water or cold air. What could be important is how much water is left in the pool if you don't add some. You don't say how far down the returns are (or vice versa, how far up from the bottom). The water provides support for the pool walls. If too low ground pressure can cause the walls to start to collapse in. On mine, the returns are about a foot (haven't measured) below the normal water level, so I drain to just below them. I have a mesh cover, so rain and snow melt refill the pool - most of the time back to normal. When I uncover in the spring, the returns are always under water or still in ice, and no issues after 20+ years.
Ice damage is from the expansion when it freezes, and is trapped someplace that won't let it expand. That won't happen for plugged returns. It is something to think about if the skimmers get water in them - hence the use of "gizmos" and pool noodles there to give the ice some expansion room.

 

[StillSyeina]

Are the returns sealed with plugs on the pool side? If so, no harm will happen if they end up under water. The liner won't care about frozen water or cold air. What could be important is how much water is left in the pool if you don't add some. You don't say how far down the returns are (or vice versa, how far up from the bottom). The water provides support for the pool walls. If too low ground pressure can cause the walls to start to collapse in. On mine, the returns are about a foot (haven't measured) below the normal water level, so I drain to just below them. I have a mesh cover, so rain and snow melt refill the pool - most of the time back to normal. When I uncover in the spring, the returns are always under water or still in ice, and no issues after 20+ years.
Ice damage is from the expansion when it freezes, and is trapped someplace that won't let it expand. That won't happen for plugged returns. It is something to think about if the skimmers get water in them - hence the use of "gizmos" and pool noodles there to give the ice some expansion room.

Sorry, my returns are about 15 inches up from the bottom and water is drained to 3 inches below- there is about 12 inches of water left in the bottom of the pool on the shallow end. Yes, they're sealed. There is usually 3 feet of water in the shallow end I think. I'll put about 6 inches back in then. Thank you