Where Does Water Go When Pool Leaks?

Change is constant. The condition of the swimming pool will never remain the same after the first perfect construction.

A component might need to be repaired, the water condition might worsen, and other situations that warrant intervention might arise. An incomprehensible decrease in the volume of water in a swimming pool will give the owner concern, especially if there are no signs of where the water goes.

Evaporation also reduces the volume of the water. Still, if it’s more than the normal rate or the bucket test signifies a vast difference in water level, there’s a leak somewhere.


Where Does Water Go When Pool Leaks

Where Does Water Go When Pool Leaks?

The water logs underground. It sinks into the soil below the pool and could cause a lot of damage to the pool or any erected structure near it. Sometimes, an area near the swimming pool begins to get wet, or water leaks will be seen if the affected component is above-ground.

Many pool owners assume there is a leak, whereas the swimming pool is opened to direct sunlight, and there are excessive swimming activities that prompt water splashing off in it. This will push us to examine the signs that will be noticed before it can be concluded there’s a leak in your swimming pool.


Signs Of A Leak In A Swimming Pool

The level of the leak or the number of locations where the leak happens determines how many observable symptoms you will see. In some conditions, the leaks continue for weeks before the owner will notice, but the following are common signs of a pool leak:

  1. There are visible cracks in the pool’s deck after an intense or prolonged leaking period. It usually happens in concrete, fiberglass, and gunite swimming pools.
  2. You notice the pool deck is lifting or sinking: Leaking steadily supplies water to the soil. When the soil firmness of an inground swimming pool changes, the pool deck will either start going downwards or lifts out of the ground.
  3. More than 0.25 inches of water is lost per day: Check your region’s evaporation rate and compare it with the water loss level your pool exhibits. You can cover the pool up with a pool cover to limit the sun’s influence and see if the water still decreases at the same pace. If yes, there’s a leak.
  4. The bucket test shows vast differences in water level: If the water level in the bucket test experiment is different from the one you record in the pool, there’s a leak somewhere.
  5. Wet spots around the swimming pool: When the grasses near the swimming pool become unusually soggy, and there are no continuous water splashing that reaches the area, the pool is more likely to experience a leak through one of its underground pipes.
  6. The pool has to be refilled several times a week to maintain the normal level: This sign prompts many pool owners’ curiosity and directs them to detect leaks the most. When you observe that your pool requires more refilling than normal, there’s a leak(s) somewhere.
  7. Your water bill increases exponentially: If you are using an auto-fill water system, you will notice that your water bill will go up. This is because there will be more water pumping sessions than normal. As the leaks expand, the autofill will have to carry out more processes.
  8. Tears in vinyl liners: Even without the common leak creation medium like vacuum, cleaning tools, and pools toy with sharp edges, vinyl pools experience leaking from aging or natural wear and tear. When you notice slight tears or separation, it signifies water losses in the section.


DIY Testing For Leaks In The Pool

Bucket test method:

Several home swimming pool owners use the bucket test to confirm their hypotheses and observations. Over the years, the bucket test has proved effective and accurate in testing for leakages.

The procedures are simple, and all that is required are:

  • A transparent bucket
  • Rock or brick to serve as weight
  • A tape.


  • Take the bucket and fill it up with the pool water.
  • Place the bucket on one of the steps in the swimming pool.
  • Ensure the bucket is placed where the more significant part is above the water level.
  • Check the bucket’s water level and make sure it synchronizes with the water level outside it.
  • You can mark the water level with tape on the inside and outside to ensure they match.
  • Add weighs inside the bucket to make it stable and not liable to float or turn upside down.
  • The weight will make the water level in the bucket rise again. Reduce it until it balances with the one outside, and you can even add the weight before you start the marking water level with tape.
  • Check back after 24 hours. If there’s a significant difference in the bucket’s water level inside and outside, there is a leakage.
  • Try this again with the pump on and compare the readings. If it is the same, start trying to locate the leak spot.


Water loss checking with tape

The thumb rule is that water loss in a swimming pool should never be more than 1/4 inch. To confirm if yours isn’t more than that, you can record the water level yourself.


  • Get a tape
  • Walk up to your swimming pool early in the morning and check if there are no visible signs of leakages.
  • Cut a little tape and put it on one of the pool’s walls or at the skimmer exactly where the water level is. You can use a grease pencil instead of the tape for the markings.
  • Check back after 24 hours.
  • Get a meter rule or a tape rule with an inch calibration. If the calibration is in meters, there’s no problem. You can convert your readings to inches later.
  • Mark the new level of water and measure the differences. If the difference is more than 0.25 inches, your pool is leaking.


Locating The Leak In Your Pool

After confirming that your swimming pool leaks, the following action is to seek the leakage’s location. Sometimes leakage’s location. Sometimes, the leaks don’t occur through only one medium, and a swimming pool might be leaking through several points and hence, named complicated.

Nonetheless, you can detect many common leak points yourself, and if all your efforts are in vain, you can always call for a professional pool service.

There are three types of swimming pool leaks:

  • Pool plumbing leaks
  • Structure leaks (shell leaks)
  • Huge water loss leaks

The leaks might result from a faulty component in the plumbing pipes, the pool deck, or a significant defect in the water pump. Now, let’s take the detection one after the other.


Quick guidelines for detection.

  • Turn off the filtration system and keep watch on where the water stops.
  • The leak is probably within the skimmer or the filtration system if the water level stops reducing after the skimmer opens.
  • If the water proceeds downwards and stops right at the pool light, you can record that the leak is probably in the light housing.
  • If the below the pool light, the problem lies within the components below the light. It’s usually the main drain or in the plumbing pipes.
  • If you turn on the pump and the leak gets higher, the problem is within the underground plumbing. The leak will be on the return line side of the filtration system. Look into the waste section to check if there’s water flowing away from it or the backwash pipe.

With your observation, take part of your food coloring, dye test solution, or a pH test reagent and put a few drops near your area of suspicion. If the dye is sucked through the medium or gap, you suspected, that’s a double confirmation. Remember to turn off the water pump and make sure the water is still positioned before carrying this test out. You can also check closely if there are visible gaps, holes, or tears in the skimmer, liner, or pool light. Those are usually where the leaks happen.


How To Check For Leaks In Each Component

As mentioned earlier, some leak situations are complicated – they have multiple leakages. You have to check through all the components to be sure you are correct. Some swimming pool users rush towards getting a solution to the obvious part of the leaks, and later, they see the pool shell sink or come off. It happens like that. Now, a closer look at each component:

  1. Concrete, fiberglass, and finite shells: If your pool has this type of structural type, check for cracks carefully. Look through the edges, joints, area where the pool ladder is placed, and other crack-sensitive areas. Many crack repairs are usually temporary. This is because conditions like soil pressure, construction vibrations, soil settling, and others that caused the crack in the first place will still occur. You’re advised to call a specialist.
  2. Vinyl liners: Holes and years build up over time of usage. They might result from chemical reactions from added chemicals to the liner, sunlight influence, sharp edges of pool toys, or the effects of cleaning equipment. The first precaution is to know that there should always be water inside your vinyl pool. In the sense of that, there will be a total tear. Keep putting water till a specialist arrive.
  3. Water jet fittings and skimmer boxes: Check for cracks in skimmers and put a few drops of dye towards the water jet to see if any hole sucks it off. If the water decreased steadily and stopped after the skimmer, the skimmer boxes are to be checked.
  4. Main drain: You might have difficulty keeping prime on the pump or much later than normal in the waste pipe. Turn off the pump, and put your hands on the central drain opening. Do you feel any pressure? Do this until you are satisfied with either getting a yes or no. There might also be air bubbles from the return fittings.
  5. Return plumbing: If the water decreases father when the pump is on, the return fittings are at fault, and usually, the water loss will be a lot. Pressure test the plumbing line with electronic leak detection, and you will be able to get exactly where the leaks occur.
  6. Light housing: Within the light fittings and the pool’s shell, the sealing weakens, and water leaks over time. This is usually easily noticeable.
  7. Hydrostatic valve: The hydrostatic valve balances the pressure outside the pool and the one inside so that anyone who swims in it wouldn’t feel any uncomfortable pressure. It might open up and never close when you drain the pool yourself. So when you refill, it will just keep allowing the water out. You will need a specialist to detect this, but on the other hand, when you notice a huge decrease, your mind should also think about it.
  8. Multiplier valve: The pool will lose water drastically when you put on the filtration system. This defect is easy to detect.


How To Fix Swimming Pool Leakages

You might be very optimistic about your DIY knowledge, but at this point, the best you can do is to have a pool specialist rectify the situation. If you are very nimble with repairs, you can replace the water jet, skimmer, and pool light yourself.

Light leaks: You can seal off the leaks with epoxy or caulking.

Liner leaks: Use a vinyl liner patch kit to rectify them.

Skimmer leaks: You can easily block the leak using poll putty. The leak usually occurs due to a gap between the concrete pool and the skimmer box.

You can search online for pool repairers near you and take your time to look at the reviews present on the sites.


Final Thoughts

Leaking swimming pools are not to be handled with little concern. They can result in the collapse of nearby structures if the water logs underground.

You can also run a risk of complicated swimming pool conditions. If you’re using a vinyl pool, the liner gets damaged when the water dries off. The best you can do is summon a specialist and sort the leaks as soon as possible.

Leave a Comment