Is The Water In Your Pool Leaking Or Evaporating? Here’s How To Find Out

Are you a homeowner who has been noticing that the water level in your swimming pool has been dropping rather rapidly? If so, you have to determine if the pool is actually leaking, or if you're just losing a lot of water due to evaporation. Pool water, no matter how much chlorine you put in it, will still evaporate. If you're having hot weather, even in winter -- and in the more southern parts of the country, a winter heat wave is not unheard of -- the water will evaporate more quickly. Here are a few tests you can do to determine if the problem is just evaporation and to determine where the problem is, if you're dealing with a leak.

  • Fill your pool up to a certain point and mark the level of the water's surface. Do the same with another container outside the pool.
  • Place the container in an area that gets the same amount of sun as the pool, but ensure your pets or other animals can't get near the water (so there's no risk of them drinking it).
  • Note the time and double-check that the water in both the pool and the container is at the mark you made.
  • Leave the two alone for a day or so -- no swimming, no maintenance, nothing that would disturb the water.
  • Check the two again and see where the water is relative to the marks.
  • Measure the distance between the mark and the water's surface in both the pool and the container.

If the distance is the same for both (approximately), then you're dealing with evaporation that's probably just more apparent than normal. You can combat this by getting a cover for the pool and keeping the cover on whenever you're not using the pool.

If the distance is different, though, then you've got a leak on your hands. Look around the pool and inside. If you can't see any cracks or rough patches that could indicate a crack, look for areas where the water seems to be moving a little. Look around the seams where the liner meets the pool edge or the lights; check the skimmer, and so on. If you think you see something, drop a little food coloring into the water near that spot -- do this carefully so that you don't make the water start moving yourself. See if the food coloring starts drifting toward the spot where you saw the water moving toward the suspected leak.

Equipment Operation Can Provide Clues

If you still can't find anything, you might want to redo the surface-level experiment again, but this time with the pool equipment off and then on. If the water loss still occurs with the equipment off, that can point toward a liner leak, though that isn't always the case.

At this point, it's time to call an in ground pool repair company. They can identify where the leak is and fix the plumbing or structure that is malfunctioning. You might want to periodically repeat the surface-level experiment every few months just to see if a new problem has occurred. Remember, smaller leaks are easier to fix than larger leaks, so early detection is best.