Finding A Leak
If you think you have a leak (an you might, but maybe you don’t)
At some point, all pool owners feel that their pool is leaking! Most often we hear of this as we approach the swim season, and are coming off of winter, when there is little, or no, evaporation. All of a sudden the weather warms and we all have leaks! Instead of worrying, here are a couple of ways to check to see if you really do or do not have a leaking pool:
1. Bucket test. This is the simplest and easiest method for determining if you have actual water loss, or just evaporation. Take a five gallon bucket and partially fill it (maybe 2/3) with water. Take a Sharpie and make a line at the water elevation inside the bucket, then set the bucket on the top step of the pool or spa suspected of leaking. Make another line on the outside of the bucket where the water elevation is in the pool/spa. Leave the bucket for 2-3 days and compare the drop of water elevation in the bucket versus outside the bucket. If they are pretty even, then you have evaporation. If the water is significantly below the line on the outside of the bucket versus the inside, you have a leak.
2. Dye test. If you determine that you do have a leak with the bucket test, you can test the pool with some Phenol red from your test kit, or some food coloring. Keeping your thumb or finger over the tip of the dye, take the bottle down around every wall penetration (pool returns, lights, vacuum line, etc.) and squirt a small amount of dye near these (make sure your pool pump is not running while doing this test!). If the dye hangs like a cloud, there is no leak. If the dye is quickly swept away, you have found your leak! Sometimes you have to try this a couple of times if you think you’ve found a leak, just to be sure (moving your hand away quickly will disturb the dye and give you a false reading).
3. Pressure test. Sometimes you will have to have a leak detection or pool plumber come out to locate a leak. Pool plumbers are able to pressurize the system and put a gauge on the lines to determine if they are holding pressure or not. If the line does not hold pressure, the pool is leaking. Once this has been determined, it may take a leak detection company to locate the general area of the leak, as the plumber may be able to only isolate a certain section (suction, return, pool, spa, etc.) of the pool plumbing, and not the actual area of the leak.
Obviously, numbers 1 and 2 are free, and most pool owners are able to adequately handle these tests. A pressure test usually runs several hundred dollars to perform, as does leak detection. The repair costs, if there really is a leak, depend on how bad, and where, the leak is.
Always try a bucket test and/or dye test first if you suspect a leak. Most times this will put your mind at ease and point to evaporation.