Free and Easy Way to Find And Repair A Leak In Your Swimming Pool


Discovering you have a leak in your swimming pool is always a frightening discovery. You start to wonder if you’ll need to drain your pool, destroy the surface of your pool, or have expensive pool plumbing work done. The good news is, most pool leaks are fairly easy to detect, and just as simple to repair.

Determine if You Have a Leak
First you need to figure out if you even have a pool leak. The easiest test for finding this answer is the “Bucket Test.” To perform the bucket test, fill a bucket with water from the pool and set it on the steps of your pool with the top of the bucket above water level. This will keep the water in the bucket the same temperature as the pool. Now, wait several days, and compare the water loss in the pool to the water loss in the bucket. The longer you wait, the better. If you see a difference, you have a leak.

Finding the Leak
This step is easy. Make sure your pool is filled to a decent level (about half way up the skimmer). Now mark the level of the water with duct tape, and turn your filter on for 24-48 hours. Make a note of the water level. Now, fill the pool back to the original level, and turn your pump off for the same amount of time you ran it with the pump on. Again, note the water level.

If you are losing more water with the filter system running, the leak is on the pressure side of your plumbing somewhere PAST the impeller of the pump. If you are losing less water with the filter system not running, the leak is on the vacuum side of your plumbing somewhere BEFORE the impeller of the pump. Please note that in this case, most of the time the pool only loses water when the system is off and not when it’s on. If the water loss is the same, then your leak is in the structure of the pool and not in the plumbing.

Dealing With a Leak in the Plumbing
Let’s deal with a leak in the plumbing first. We will assume that there is not an obvious leak (one that you can see) on the filter system. Did you check where your backwash line comes out? There are two ways to find this leak. First, you can pressure test the lines, then dig, following the leaking line till you find it. You can also call in your local leak detection service. We would highly recommend the latter, unless you like to dig. Professionals will use “geophones” to listen for the leak and only dig where necessary!

Dealing With a Leak in the Structure of a Concrete Pool
You will need some food coloring for this, and you will want to turn off the pump at least an hour before you do this. In a concrete pool, any cracks in the shell are usually obvious. By squeezing out the food coloring near the crack, you will see the crack pull the food coloring in. That will show you where the pool is leaking. Yes, you may have to get in the pool to do this, but isn’t that why you got the pool in the first place? If there are no visible cracks, you will want to squeeze out the food coloring around any of the items that pierce the shell of the pool (main drain, returns, lights, etc.). Be sure to check the “mouth” of the skimmer where the plastic of the skimmer meets the concrete. This area is very susceptible to movement and often separates causing a leak.

Once the leak is found, it is easy to fix using a patching material. Most of them will work under water. After patching, check again with your food coloring to make sure you plugged the leak. Please note that if you patch near a fitting, you will want to leave the pump off while it cures, so the flow of water doesn’t wash the patch away.

Hopefully, these steps will lead you to a leak-free pool. If you find you still have a leak in the pool, contact your local pool service company, or give us a call for a few more steps.

Related Posts

  • Attili Sattibabu

    We should thank you for giving such a creative blog. Your site happens to be not just knowledgeable but also very stimulating too. We come across a limited number of experts who can write not so easy content that creatively. We look forward to much more !!

  • Plumber Walnut Creek

    Great stuff! I never thought that you could detect that so easily, regarding the bucket test thought the weather also have an effect on that one because the longer you wait the water in the bucket will also evaporate.

  • admin

    That’s true, but you usually try to avoid rain when doing the test.