Every Spring, above ground and in ground swimming pool owners pull off their winter covers – and panic.  The water level they saw when they closed up the pool for the winter has dropped significantly.  The pool must have a leak, they assume.  Nervous calls are then placed to the professionals who sold or winterized the pools.  “How did this happen?  What should we do?  Will this be a costly repair?”

The answer may come as a surprise, but the cause of the disappearing act may be as ordinary a phenomenon as an ice cube dropped in a cup of water.  Add enough ice, and the water spills over.  It’s called displacement.


Water displacement in  above ground pools is quite common.  Over the winter, the weight of the snow and ice push down on the cover, which can cause the cover to displace some of the pool water.

The displaced water spills out harmlessly onto the deck, unbeknownst to the pool owners.  When the cover is removed, less water will be found remaining in the pool.

Despite its simplicity, the concept can be difficult for people to grasp right away.  So to demonstrate fill a glass of water to the rim of the glass, place a napkin over the glass. Then slightly push down in the middle of the glass allowing a little water to spill over. This has helped me explain this many times.Water overflow

We try to explain that the pool usually has a solid block of Ice on the cover for 3 to 4 months throughout the winter with periodic snow build up and while you cannot stop the water displacement  there are a few steps that can be taken.

  1. Periodically remove ice from the cover. (Be careful not to damage your cover).
  2. Sweep off the snow with a broom
  3. Once the ice on the cover melts, using a cover pump and pre-filter pump the water from you cover into you pool.

But if, when a pool’s cover is removed, the water appears to have been displaced, Teddy Bear Pools & Spas recommends the following advice:

  1. Refill the pool to the desired water line.
  2. Wait 36 hours.
  3. If the water again has dropped, then perhaps there is a leak. If the water has maintained its level, the pool has suffered from nothing more than a little winter water displacement.

[button link=”” style=”download”]Download Printable Copy[/button]

[twitter_follow username=”TeddyBearPool” language=”en”][fbshare type=”button” width=”100″]

Leave a Comment

You must be logged in to post a comment.