How much water evaporates from a swimming pool in a day?

On average, swimming pools lose about a quarter of an inch of water each day, yet variations in wind intensity, humidity and sunlight can drastically change water loss rates. Pool owners who notice a sizeable water loss should implement the bucket test for pools to determine whether the pool is leaking or is just experiencing routine water evaporation. You will need:

A clean 5 gallon bucket
A permanent marker or bright colored tape
A heavy object (ex: large rock or brick)

Turn off all waterfalls, fountains, and auto-fill, and do not backwash or splash water out of the pool during the test. After everything has been turned off, wait for your water to calm and become still.

How to conduct the Bucket Test for Pools?

Bucket Test for Pools Procedure:

Bring the water in the pool to its normal operating level and turn off your auto fill device.
Fill an empty bucket with pool water to about one inch from the top of the bucket. (By filling the bucket close to the top you are ensuring that air movement over the surface of the bucket will be similar to that of the pool.)
Place the bucket on the first or second pool step. To keep it from floating away it may be necessary to place a few bricks or rocks into the bucket. (By placing the bucket in the pool water you are ensuring that the water temperature of each will be similar).
Mark the water level inside the bucket.
Mark the water level of the pool on the outside of the bucket.
Operate the pool for 24 hours as it had been operated when a leak was first suspected.

After 24 hours, compare the two levels. If the pool water outside of the bucket (outside mark) goes down more than the inside water level, there is probably a leak.

Test Results: Calculating Water Loss

To more effectively visualize the leak or leaks you have it will be helpful to translate inches of water lost into gallons of water leaking. First, subtract the bucket loss from the pool loss. The result will be inches of water lost due to leaks.

You can also use this leak detection Water Loss Calculator.

Professional Help: Post Bucket Test

Owning a pool should be about fun and relaxation – not water worries. With 18+ years of industry expertise, Heritage Pools offers a full list of services, including leak detection and leak repair. Once you determine your pool is actually leaking or for additional information, call us at (843) 762-3417 or fill out our contact form and we can provide you with the various options for fixing your pool problem.