Evaporation Rate For Above Ground Pool

How much water can evaporate from a 24 foot above ground swimming pool in a day with a cool and windy night?


Hi. An above ground pool could loose between 1-2 inches of water a week due to evaporation. This is not by any means a scientific number; it's just what I have experienced here in the Arizona area.

There is a more scientific way to know for sure if your pool is evaporating, or leaking. You need about a five gallon bucket and a magic marker. Fill the bucket full of water and place a mark at that level on the inside of the bucket. Find an out of the way spot on your pool and do the same thing, place a small mark right at the water level on the pool liner.

At the end of a week you simply measure the distance between the mark on the bucket and the water level. Do the same thing with the pool, measure the distance between the mark on the liner and the water level. Believe it or not, the bucket and the pool should have the same amount of evaporation. That means the measurement in the pool should be the same as that in the bucket. If the bucket measures one inch and the pool measures two inches you have a leak.

Use this method anytime you think your pool may be loosing water, it is always accurate.

If the pool is loosing more water than the bucket don't overlook the possibility of water splashing out. Kids can easily do that.

Evaporation Rate on 24 ft Round Pool

by Gary Whitcher
(Michigan)

What is a normal evaporation rate in Michigan on a 24ft round pool?


Hi Gary. I'm not sure there ever is a normal evaporation rate because it depends on so many factors, like temperature, humidity ect. There is, however, a way to see if you pool water is evaporating or leaking.

You will need a five gallon bucket filled with water. You take a marker and mark the water level on the inside of the bucket. You do the same on the inside of the pool, on the liner. After a few days the bucket and the pool should be loosing water at the same rate. You would measure from the line to the water level in the pool and the bucket, they should both have the same measurement.

If your pool measures a half inch from the line to the water and the bucket measures only a quarter inch it is safe to assume you have a leak in the pool.

If you think it is a hole in the liner this page might help.

Holes in Vinyl Pool