Evaporation is the natural process of converting liquids into vapor. Evaporation of your swimming pool water occurs at different rates depending on the weather conditions. According to the U.S. Department of Energy, dry and windy weather speeds up the rate of evaporation, while warm and humid weather slows it down.
Pool Evaporation Rates
Pool professionals believe that evaporation can lead to water loss anywhere between one-half an inch to as much as three inches per week, depending on conditions. If pool owners are losing more than that, it could be a sign of a leak somewhere in the pool or within the filter system components. Normal activities such as splashing due to swimming activities shouldn't significantly affect water loss.
Solar covers can limit evaporation from your swimming pool and heat the water for swimmers. Solar covers are constructed from UV-stabilized plastic or vinyl. The covers create a vapor barrier between the air and the pool water, thus slowing the rate of evaporation. Solar rings are constructed from the same material as the plastic solar cover, but are easier to apply and remove from the pool surface. These plastic rings are placed next to one another on the pool surface. Many solar rings have magnetic edges that keep them locked together and prevents them from overlapping on the surface. Solar rings should cover about 80 percent of the pool surface in order to be effective.
Leak Detection Test
Compare evaporation rates between a bucket of water and your pool to determine if the pool has a leak. Fill up and place a 5-gallon bucket of water next to the pool. Draw a line at the water level on both the pool and bucket. Wait 24 hours and compare the water levels. If the pool lost more water than the bucket, it's may be an indication of a pool leak.