The Ultimate Guide To Finding & Fixing A Swimming Pool Leak



We all know swimming pools get wounded from time to time, but that doesn’t make fixing an unexpected leak any less hassle, right?

Fortunately, there is a way to make fixing your pool a surprisingly quick and painless process, so you can get it patched up and ready for swimming again in no time.

In this article, I’ll cover the exact steps you need to take in order to identify and fix a leak for both inground and above ground pools.

Is Your Pool REALLY Leaking? Maybe Not.

Before you start freaking out over how much water your pool is suddenly losing, consider that it may just be a false alarm.

As you no doubt already know, losing water is just part and parcel of owning a pool thanks to evaporation (thanks evaporation!), so it could just be that your pool is simply evaporating at a faster rate than before.

In fact, in the right conditions, it’s entirely feasible that your pool can lose almost 2 inches of water per week. (That’s right, per WEEK.) Why would it suddenly start evaporating faster?

  • Higher exposure: If your pool is getting more exposure to sun for whatever reason, evaporation will of course speed up. You can combat this by screening or shading your pool.
  • Temperature: Depending on where in the world you live, perhaps the most obvious reason is that it’s just getting hotter. Even the warm nights slowly chip away at your pool.
  • Humidity: If the humidity outside is low, the dry air will be able to suck up your pool water at a much higher capacity than it would in high humidity, where the air is already occupied.

What Causes A Leaky Swimming Pool?

Aside from knowing whether or not you actually have a leak, figuring out what caused it can be another headache in and of itself.

The truth is, there are a number of things that can create a leak in your pool and in some cases, like seals deteriorating or movement in the ground, it’s not really something you can prevent.

That’s not always the case, however. To some extent, you can avert disaster by making sure your plumbing is installed and maintained correctly, as well additional pool fittings that are prone to leakages. (Of course, a lot of the time we put our trust in the professionals to take care of this stuff for us.)

In any case, identifying the cause and taking preventative measures is important for both the welfare of your pool, but also your finances as it’s a huge waste of water, heat and chemicals.

How To Check If Your Pool Has A Leak

If you’re still convinced your pool has a leak, there is a ninja trick you can deploy, and it’s what we in the biz like to call the The Bucket Test.

The Bucket Test works by applying the same water conditions in your pool, to the water in a bucket. This allows you to very easily check if water is lost at the same rate.

Follow these steps to find out if you have a leak.

Step #1 — Fill A Bucket With Pool Water

Take a regular, everyday bucket and fill it with pool water to roughly 1-2 inches from the top of the rim. The reason for using your pool water is to make sure the test is fair in terms of having the same water temperature.

Step #2 — Position The Bucket In Your Pool

With the bucket almost fully filled with water, place it in your pool so that the water in the bucket is level with the water in your pool. Use your pool steps to position this just right. The reason for having the bucket slightly above water level is to emulate the air movement similar to that from the edge of the pool walls.

Note — It may also be necessary to place something heavy into the bucket in order to hold it in place.

Step #3 — Mark The Water Level

While it is possible to eyeball the results of this test, I highly recommend that you mark the water level on the bucket with a black marker, or even some tape. You’ll need to do this on both the inside and outside of the bucket, so you can easily compare the water levels later on.

Step #4 — Wait 24 Hours & Check Results

Once everything is in place, it’s just a case of keeping your pool running under normal conditions for about a day. (In the event of rain, you will have to start again.) If, after 24 hours, the pool water level has decreased by the same amount as the bucket water level, you do not have a leak. However, if the pool water level has decreased more than the bucket water level, you probably have a leak.

Step #5 — Repeat The Test

Doing the test under different conditions allows you to establish roughly where the leak can be located, so you’ll want to repeat this again with your pool pump off. Here’s a quick guide on what the results indicate:

  • If you lose more water when the pump is off, the leak will likely be found in the return lines.
  • If you lose less water when the pump is off, the leak will likely be found in the skimmer and main drain.
  • If you lose the same amount water when the pump is off, the leak will likely be found in the shell, pool liner or fittings.

How To Find The Leak In Your Swimming Pool

So we’ve already established how to detect a leak in your pool versus a bad case of evaporation, but how do you actually find it?

For that, I recommend using a simple little swimming pool hack, called The Dye Trick. It’s pretty straightforward, but I’ll run you through the steps anyway — because I’m just nice like that.

Step #1 — Get Yourself Some Dye

If you have any dye or food coloring lying about your house, now’s the perfect time to go and dig it out. If you don’t have any to hand, you can grab some at a local store.

Step #2 — Get Into Your Pool

This part involves getting your hands dirty (or should I say, wet) because you will need to get into the pool and submerse yourself — with the dye in hand. Using goggles for this is a must and preferably a snorkel to help you stay under the water for longer periods of time. (This will really speed up the process.)

Step #3 — Release The Dye

While underwater, release the dye, in bursts, around the areas of your pool that have visible cracks to see if it gets sucked into the crack, which will reveal the source of the leak. If there are no obvious hotspots in your pool, it’s best to start out with areas that pierce the shell of your pool, like the main drain and return lines.

Note — Try not to disturb the water too much as you’re doing this, as the dye will disperse and make identifying the leak a lot harder.

See This Process In Action!

In case you’re still not sure how this works exactly, you can check the video below to see the Dye Trick in action.

Still Can’t Find The Leak?

There are times where the DIY approach just doesn’t cut it, and experts with specialist equipment should be called in. If this is the case, I highly recommend Googling for a local pool repair company to come out and take a look.

They may use techniques like:

  • Pressurizing: Using compressed air, they will pressurize your pipes to see where air pressure falls along your pipe. This will also force bubbles from the compromised area, making it easier to identify.
  • Camera: They may instead feed a television camera through your pipes to locate the leak, listening for water escape with a very sensitive microphone.

This could cost you anywhere from a couple hundreds to even a couple thousand dollars in the worst cases, but at least you’ll know it was done properly.

How To Fix A Leaky Inground Swimming Pool

For most inground pools, validating and identifying a leak is something that you, as a pool owner, can usually DIY without too much trouble. Fixing it, however, is an entirely different beast depending on the type of pool you own, and where the leak is, specifically. Here’s a quick breakdown of the different repair options:

  • Skimmer leaks: This will usually be caused by some separation between the your pool and the plastic skimmer, and can be patched up with pool putty. (Like this one)
  • Light leaks: This is likely a conduit pipe that has deteriorated or come loose. A two part epoxy that dries hard, with putty, silicone or caulk are ways to fix this problem. (Like this one)
  • Liner leaks: This is one of the better problems to have since it’s an easy fix using a vinyl liner patch kit. (Like this one)

If the problem persists or is outside the scope of what’s mentioned here, I recommend looking at more in-depth guides on DIY pool repair, like this one and this one.

Otherwise, it may be a good time to call in the experts who will be able to use specialist equipment to locate and fix the leak very quickly.

How To Fix A Leaky Above Ground Swimming Pool

Above ground pools are wayyyy easier to deal with because not only is identifying the leak a piece of cake, but in most cases, it can also be fixed with a simple vinyl patch kit. Here’s a quick breakdown of how it’s done:

  • Step 1: Measure the size of the leak and cut a piece of vinyl that is 2 inches larger than the area around the hole. (You can round the corners off with scissors as well.)
  • Step 2: Apply the waterproof adhesive (supplied in the kit) to the piece of vinyl you just cut. Follow the supplied instructions for exact amounts.
  • Step 3: Get into the pool, and using goggles, apply the patch eventy to the inside of your pool, covering the damaged area. Hold for around 60 seconds.
  • Step 4: Additionally, you can also use a pool repair putty mixture on the outside of your pool as an added measure.


Dealing with pool leaks is, unfortunately, one of the things we, as pool owners have to deal with from time to time. (And always at the wrong time, it seems.)

The good news is, if you follow the steps outlined in this article to find and fix a leak in your pool, you’ll cut out most of the headache and get everything up and running again in a jiffy. Good luck and happy swimming!

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This is a detailed guide that will cover the exact steps to identify and fix a leak for both inground and above ground swimming pools. So you can get everything up and running again in a jiffy. #poolmaintenance #poolonomics

Categories: Pool Care, Pool Problems