Pool Leaking or Water Evaporating?

By September 24, 2017 June 22nd, 2021 Cleaning & Maintenance, Water Chemistry
Pool Leak or Evaporation

Rule of thumb is if you are losing more than one-quarter of an inch a day in a humid environment or one-half an inch a day in a dry environment- you should check if your pool is leaking.

Clients are often confused about the difference between a pool leaking versus evaporation. This is a common question and we can offer some easy guidance

Let’s talk for a second about those rules of thumb.  Evaporation varies based on wind speed over the pool, humidity, pool surface area, and water air temperature variance.  Pools in windy areas tend to lose more water to evaporation.  Swimming pools in dry environments lose more water than do pools in humid ones.  Pools lose more water to evaporation when they have more surface area.  If you heat a pool during winter you will lose more water than a non-heated pool due to temperature variance to the environment.

If you think you have a pool leak you should:

  1. Turn off your auto-fill device if you have one.
  2. Turn the pool off at the breaker so it won’t kick on.
  3. Fill your pool to normal operating height – usually halfway up the skimmer.
  4. Mark the water level in the skimmer.
  5. Fill a bucket with pool water to one inch of the top and place it on the top step of the pool. This is our control group.  Mark the bucket the way you marked the skimmer.
  6. This won’t be perfect if part of your pool gets a lot more wind than another. If you have a deep end swim out in more wind use a bucket and put the full bucket on the swim out where it gets the same wind.
  7. Check the two lines in 24 hours.
  8. Note your results (pictures help) and refill the pool and bucket to the lines.
  9. Repeat the test with the system running continuously for the next 24 hours.
  10. Note your results.

If the water went down a similar amount in the pool as well as the bucket, then you lost water due to evaporation.

If it went down more in the skimmer and not much at all in the bucket then you have a pool leaking.

If the water went down with the system off versus with it on, the test indicates a structure leak or hole in your suction side plumbing.

If the pool loses water only when running, it indicates a leak on the pressure side.

This will mean something to a pool pro, record all the information.

Please remember, finding one leak and fixing it does not mean you have found all leaks in a pool.  A Pool Professional can help.  Contact Pool Troopers today for help.