What to Do if Your Above Ground Pool Overflows

We never want our above ground pool to overflow, but hey, it can happen.  The culprits are leaving the hose on too long or a rain storm. If we know the rain storm is coming, we can lower the pool water level to make room.  Remember, it is always better to PREpare than to REpair.  An overflowing pool can be a nuisance.  Let’s talk about what this causes and the fixes.

Potential Damage

What can happen if your above ground pool overflows depends on a variety of factors.  What kind of landscaping you have on your property is a large factor.  How close to your home the pool is another factor. If you have the proper drainage system, then your water chemistry is the only thing you will have to worry about.  But we will talk more about that later.  Huge amounts of rain combined with improper drainage can cause flooding, obviously.  This can be a big concern if the pool is close to your home as it can cause structural damage. 

Proper Drainage

Hopefully, this was considered when you installed your above ground pool. Obviously if ALL of the pool water was to be unleashed, this would pose a huge issue.  Did you know even small amounts of water can cause problems to your yard and other structural damage.  I learned that having the proper landscaping that allows for draining can play a mega role. We ideally want the water to drain away from our homes and other structures.  Aside from rain, water can run off of the roof of your home, deck or shed so keep that in mind.  Even if it doesn’t overflow your pool, it will still unbalance the water.


Always keep an eye on the weather.  If you see a huge rainstorm coming, you can be proactive by lowering the water level in your pool to make room for the rain water. This allows your yard to deal with the rain flow versus your swimming pool. 

What to Do if the Water Level is too High

  1. One option is to siphon out the water using a garden hose.  Suck on one end of the hose and then submerse it into the pool water.  Make sure you are directing the water to a safe place, not towards your home, for example.
  2. You can use your pump drain.  Many pool pumps have drain spigots.  Remove the cap and the water should flow out.  Unfortunately, there is no way to direct the flowing water, but this method is easier than trying to siphon the water. If you have a newer pump like these, they come with a drain plug. https://poolpartstogo.com/collections/above-ground-pumps
  3. Buy or rent a submersible pump.  This is the easiest, fastest way to get rid of any excess water.  If you are in a State that is prone to rain storms, it makes sense to invest in a submersible pump.  They are a couple hundred bucks depending on how much water they pump out and how quickly it does it.  Hardware stores like Home Depot or Lowes also rent submersible pumps.  See them for pricing because it usually is dependent on how long you will have the pump.  Make sure the other end of the hose is directed away from your home or other structure.

Water Chemistry

It all depends on the pH of the rain to determine if your swimming pool’s pH is going to get higher or lower.  Adjust your pH first as it allows for the chlorine to be more effective when the pH is in range.  The rain has basically diluted all of your chemicals.  You may need to shock your pool to break down any contaminants and organic load and still leave you with a chlorine reserve.  Also check your alkalinity.  You cannot get a proper pH reading without first checking your alkalinity.  If it is too high, lower it with sodium bisulfate, which is a granular form of dry acid.  If it is too low, raise it with sodium bicarbonate, which is also known as alkalinity up.

If your calcium was on the low side before the overflow, you may find yourself needing to adding calcium chloride.  One name of this product is “Hardness Plus”, but your local pool supply store may call it something else.  Too low of a calcium level can cause the water to try to leach it out of the pool vessel.  If your calcium was high, congrats!  One good thing came out of the overflow.

Since rain water is organic, don’t be surprised if you find yourself with a high phosphate level.  Phosphates are only a problem when they are a problem.  What I mean by that is that by themselves, they are harmless.  But since they are food for algae, you don’t want to have a Las Vegas buffet laid out in the event of an algae bloom.

It may be a good time to test for metals in the water.  Most home test kits don’t test for this.  Copper and other metal test strips are available.  It probably makes the most sense to take your water into your local swimming pool supply store for a water test as they test for obscure things such as metals.  Many stores offer this service for a nominal fee or even for free.  You will also receive a sheet with dosing instructions to get your pool water back into shape.

Testing at home?  Always read the product instructions before adding any chemicals and wear the proper safety gear.  If you are unsure what to add, you can download apps that you can put your findings in and using the Langelier Saturation Index, will give you precise dosing instructions based on the gallonage of your swimming pool.  I personally like the Orenda App.  And it's free! 

So, while we don’t want our above ground swimming pools to overflow, it can happen.  Now we know a little bit more of what to do to prepare and repair this annoying issue.  See you poolside!