I Think My Pool Is Leaking—How Can I Be Sure?

PRE-SEASON:

In the spring, Watercrafters gets many calls from homeowners that take off their winter covers only to find that the pool has lost a significant amount of water. The usual cause for this is leak in the cover. Oftentimes, the cover will get a small hole in it. When you pump off the top of the cover, you may be pumping water from underneath the cover at the same time. To find out for sure, follow these steps:

  • Remove the cover completely and mark the water level.
  • Refill the pool with 4-6” of water and mark the new level.
  • Monitor the water level over 3-4 days.
  • If the water level holds, continue filling the pool 4-6” and monitoring it.
  • If the water level drops, mark where it stops. This is the level of your leak.

IN-SEASON:

During the heat of the summer, your pool may need refilling more often than you think it should. To confirm whether you are experiencing evaporation or a leak, do a “Bucket Test” by following these steps:

  • Fill a bucket halfway with pool water. Mark the water level inside the bucket.
  • Set the bucket on a step in the pool and mark the water level on the outside of the bucket. (This keeps the water in the bucket at almost the same temperature as the pool water.)
  • Monitor the levels over the course of 3-4 days. If the water on the outside of the bucket drops faster than the water on the inside of the bucket, you have a leak.

Once you determine that you do in fact have a leak, next you will want to find out if it is in the equipment or the pool shell.

  • Shut off your equipment and mark your water level. Monitor the water loss over 1-2 days.
  • Turn the pump back on. Monitor your water loss over 1-2 days.
  • If you lose more water while the system is operational, it is probably NOT a pool shell leak. The most likely place is a leak out the backwash line or an underground return line.
  • If you lose the same amount of water with the pool running or with it off, it is probably a structure or shell leak. The most likely places for a this are the underwater light, a hole in a vinyl liner or a crack in the skimmer.