What to do if you think your pool is leaking
The largest amount of water loss from the pool is due to evaporation.The rate of evaporation can vary greatly depending on several conditions.Water temperature, wind, air temperature, relative humidity, use of sprays or waterfalls among other things will effect the rate of evaporation.On a dry windy day, a pool can lose as much as a quarter of an inch of water a day.If you think your pool is leaking, the first thing to do is to check the circulation equipment. Is a motor leaking? Filter? Any pipes? Any above ground leaks should be repaired first.Is the pool leaking to backwash? If you have a sand or D.E. filter, the seal in the backwash valve can fail allowing water to bypass to waste. Check the sight glass if you have one or in many cases you can see were the water leaves the backwash pipe. Look for a “P trap”. There should not be any water coming out the line, even a drip can add up to quite a bit of water.If you run aerator sprays or waterfalls, of course this will accelerate evaporation.If you have a pressure cleaner, make sure it’s not shooting water out of the pool, at least not more than normal.
To check for an underground leak, we will do a “BUCKET TEST”.Basically, the bucket test exposes water in a bucket to the same conditions as those affecting your swimming pool. By comparing the water loss in each, it is possible to determine if the pool is leaking or if supposed leaks are just the result of water being lost to the air.
First, fill the pool to the normal level.Fill a bucket, (an old chlorine bucket works well) to about three or four inches from the top, we want air movement over the bucket to be similar to that of the pool.Put a few bricks in the bucket to hold it down, and set the bucket on the first or second step of the pool. This will make the temperature as well as the air movement similar.Mark the water level in the bucket, and mark the level in the pool. (Usually marking a tile line with tape or using a sharpy on the inside of the skimmer works well.)Run the pool normally for 24 hours.Check both levels. The loss in the bucket should be very close to the loss in the pool. If the level has dropped more in the pool, you probably have a leak.Also remember, if it rains both vessels should gain the same amount of water, so a bit of rain won’t ruin the test.Sometimes you can get a bit more information with the bucket test.Set it up as before, but now run the pump 24 hours straight, then measure any loss. Reset the test, and leave the pool off 24 hours. If you lose more with the pump running, you may have a leak on one of the return lines.If you think you have an underground leak you will need the services of a leak detection company. These specialists can locate the leak using ultrasound and other tools, they can usually repair these leaks also.