Vinyl Liner has Wrinkles in the Bottom


Bronze Supporter
Jun 13, 2016
Twin Cities MN
I haven't opened my pool yet (Minnesota - still have a little snow on the ground!) but it got me to thinking about something I noticed last year. There were wrinkles in my vinyl liner in the deep end of the pool. They were probably about an inch high and emanated from the pool drains for several feet. I'd say there were about five or six.

Could this have been caused by a chemical imbalance? My chemical balance is always very good, except I've always struggled with Total Alkalinity. TA has always been in the 200+ range even when all the other numbers are good. Not sure why - might be due to high mineral content naturally occurring in our water.

The second part of this question is, what should I do about it, if anything? I pretty much ignored it last year and didn't have any problems.


Well-known member
Jun 16, 2019
The two most common causes of new wrinkles are either really low PH (especially common over the off season) and the groundwater table coming up and making the liner 'float'. With an equalized pressure the liner is basically free to do as it pleases and rarely sits back down perfect when the water recedes. This is probably what happened because the liner is attached to your drains so that would hold that part down while the rest went awry.

Unfortunately there isnt much you can do for either after the fact.


LifeTime Supporter
May 8, 2012
Southeast Michigan
Some things to consider:
Check pH and TA levels before closing and make sure you balance the chemical levels. Just found several threads that deal with low pH and TA was also a culprit.

Do you lower the water level of your IGP?
Also make sure your pH is in good range (around 7.4) before you start a SLAM during opening. My pH went haywire when I didn't get it in good range and it got too low, which after doing that several times, caused the liner to wrinkle.

Also, very high levels of chlorine with low pH will cause wrinkles during the season and maybe not be noticeable under they get worse.

(I went to school in St. Bonifacius for 2 years)