Do You Drain A Pool In The Winter?

Kindey shaped gunite pool in luxury backyard during summer evening

When the swim season is over, and you’ve put away your patio furniture, it’s time to think about closing the pool.  You’ll want to do a few things on your checklist right away. First, be sure to install a quality winter cover. Second, make sure your gates are still working properly. Next, there’s nothing left in the pool but water.  Finally, it’s time to think about shutting down the pool.  When closing, do you drain a pool in the winter?

How To Drain A Pool In The Winter Properly

The most important aspect to closing a pool for the winter is to make sure you have air in the pipes instead of water. This prevents frost damage to the plumbing which is enemy number one.  Frost damage to plumbing can be catastrophic. It can lead to digging up the plumbing, finding the leaky broken pipe(s) and replacing them.  This often involves removing the deck and it can be quite expensive.  The obvious solution is to properly close down the pool. This involves filling the plumbing with air instead of water.  

Do You Drain A Pool In The Winter Below Return Inlets?

The best way to be sure you have the water out of the piping is to drain the pool down so it’s below the return inlets in the wall of the pool, about 18 inches.  This allows the service technician to use an air compressor to blow the water out from the pool equipment and clear the pipes.  Once the water is blown out of the pipes, plugs can be installed at the wall return fittings. This prevents water from getting back into the pipes as the pool refills over the winter.  

What To Watch: Pool Water Level Over Winter

In the typical winter there will be just about enough precipitation to refill the pool with melting snow and rain.  However, it is important to check on the pool level over the winter.  You don’t want the pool water level to overfill. If it does, this can cause damage to your coping and tile as ice forms around the edges of the pool.  If you notice your pool is overfilling you’ll want to pump out some water to keep the level below the coping.  

Do you drain a pool in the winter explained in suburban backyard

Do You Drain A Pool In The Winter Completely?

So why don’t we just drain the pool completely to prevent overfilling?  Well there are other forces at work that you need to be aware of.  If you were to drain the pool completely, then you would be at risk of ‘floating’ the pool.  This is when ground water pushes the pool up and out of the ground like a boat.  This is a rare and catastrophic occurrence, but it does happen.  Also, if you drain the pool completely, the depth of frost will be deeper since there is not a layer of water insulating the floor of the pool.  This could cause heaving of the floor even if there is minimal ground water.

Do You Drain A Pool In The Winter Summary

Do you drain a pool in the winter?  Draining a pool in winter is only helpful if it’s drained part way, on average about 18 inches down from operational depth.  If you have an especially dry winter, you may need to put a hose in the pool or order a load of water to top off the pool when spring comes.  It’s hard to predict exactly how much rain and snow you’ll have over the winter. Therefore, keeping an eye on your pool water level is a good idea.  If you aren’t sure you know what you’re looking for, ask your service company to do some winter checkups to make sure your pool is over wintering properly.