Knowing how much water loss your pool is experiencing on a daily basis is an important aspect of pool ownership. Calculating water loss from a pool leak is not difficult with the standard formula.
Before you calculate the total estimated water loss, you’ll need to perform a bucket test to determine the number of inches of water lost in a 24 hour period. The basic bucket test will tell you approximately how much water you are losing each day in inches. A quarter-inch is normal for evaporation. A pool or spa tub will lose less if it is covered when it is not used. You can access our bucket test instructions here.
Swimming Pool Water Loss Formula
Multiply the length (L) times width (W) times the amount of the water loss (WL) in inches times .6233 for a rectangular pool.
Example: L-32′ x W-18′ x WL 2″ x .6233 = 718.04 gallons in 24 hours.
L-40′ x W-20′ x WL 1.5″ x .6233 = 747.96 gallons.
For circular pools or hot tubs, multiply the diameter x diameter x WL x.48929.
Example: D-12′ x D-12′ x WL 1.5″ x .48929 = 106.6 gallons in 24 hours.
Divide the daily loss by 24 to get the hourly rate. In the example above, the 32×18-foot pool is losing almost 30 gallons an hour. That is a substantial waste of water that can soak the ground and lead to other problems. The loss becomes expensive when you are constantly refilling the pool.
Many pools are oval shaped or freeform designs. You know how much water your pool holds when it is filled to the recommended waterline. This formula gives you an approximation of the water loss.
The amount of water loss is an indication of the size of the pool leak. A slow loss of a half-inch per day suggests a leak in the skimmer basket. Larger water loss may indicate a leak in the plumbing system or a crack in the pool surface. Pool leaks do not go away on their own. The spa or pool leak has to be located and repaired.
The Cost of a Pool Leak
The average yard swimming pool holds 18,000 to 20,000 gallons based on its size, depth, and shape. Calculate the volume of water by multiplying the length by width by average depth by 7.5 for rectangular, square or freeform pools. Use the multiplier of 5.9 for a round or oval pool.
A rectangular pool approximately L30′ x W16′ x D5′ x 7.5 = 18,000 gallons.
The cost to refill a smaller pool with 15,000 gallons can run about $80 to $100, based on where you live. Add the expense of extra chemicals to control the pH balance and keep the pool clean. A leak is expensive if you just keep refilling the pool.
Signs You Have a Pool Leak
- Your pool loses more water than regular evaporation (about 1/4 inch)
- The pool has air in the system
- Equipment loses prime
- You see cracks
- Pool deck is sinking or lifting
- There are soggy spots around the pool
- You add water more than once a week
Finding the Leak
A leak close to the pool’s surface will stop as soon as the water level falls below the leak spot. Check all fittings near the water line where metal meets the pool surface. They must be tight to prevent leaks. Check for loose tiles around the water line.
The leak will stop if the water is at the bottom of the skimmer basket area if this is the problem. The intake line will suck in air which is harmful to the filter and pump motor. Check the skimmer basket and make sure it fits tightly against the wall. The intake plumbing line may be the cause of the pool leak.
Tears in vinyl pools are often easy to locate. Check the wall surface for any possible tears and repair it immediately. Check for cracks in the surface of cement and gunite pools. The drain needs to be checked in all pools. This should also be a tight fit since it leads to one of the intake lines.
The water level in a spa tub must always be above the intake line and the return jets. A water level below the intake pipe is an indication of a leak. When you suspect a leak, all pipes should be checked in a stand-alone spa tub.
Water on the decks and ground surrounding the pool indicates a break in the plumbing lines. Aquaman Leak Detection has a unique ultrasound system that pinpoints leaks without tearing up the deck. The pipe, usually a PVC tube, can be easily repaired to stop the pool leak.
Call Aquaman Leak Detection if your pool is losing water. We will find and repair the leak with fast and efficient service. Headquartered in Brevard County we serve all of Florida.
