The differential that occurs between the pool water temperature and the air temperature on late summer nights causes water to evaporate at an accelerated rate. In some cases you might see a water level difference of 1-3 inches overnight. Depending on the size of your pool, that can be over 500 gallons of water loss!
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.
Answer: The 1/4" per day rule refers to a 24-hour period. Much of the evaporation will occur during the day due to the presence of the sun. However, you will still have water loss during the night as well.
If your pool lost water overnight and it is more than the quarter-inch due to evaporation, you probably have a leak. Evaporation accounts for a minor amount of water lost each day. Losing a half-inch or more overnight indicates a problem.
Depending on various environmental factors—including your location, average daily temperature, and the amount of sun your pool gets every day—your pool may lose more than half a centimeter of water every day. This translates to just under five centimeters a week, on average.
Pool Is Losing 1 Inch of Water Per Day
Losing more than ½” of pool water per day indicates you likely have a leak in your pool's structure or your pool pump system. You should call your pool service for a thorough leak inspection. You might not be able to keep up with refilling your pool at this point.
What is this? As a result, most evaporation actually occurs at night. This might seem counter-intuitive, but the reason is that at night the pool water is relatively warm, but the air temperature has dropped. Therefore, the difference between the air and water temperatures is greater – thus, more evaporation occurs.
Most pools experience between 3mm - 7mm of water loss each day, depending on where you live.
Look closely at the filter, pump, heater, and pipe valves, which is where leaks often tend to occur. If you have a vinyl pool liner, look for tears or separations around the fittings, lights, steps, and corners.
A pool leak isn't typically an easy-to-find issue but they most commonly occur in corners, at the tile line, near pipe openings, around lighting or at the throat of the skimmer.
Evaporation occurs whenever you expose wind or air to the surface of your pool. So in short, this applies to every pool, all the time. Water molecules rise to the surface, form into a vapor and eventually get released into the air. Heated pools on cool nights experience evaporation more rapidly.
The average pool water evaporation rate is about a quarter of an inch of water per day or more than two inches in a week, which on a 33′ x 18′ swimming pool (an average pool size) is more than 2500 liters or approximately 600 gallons a week; this may vary depending on your climate and the factors listed above.
An uncovered pool will lose water in the winter to evaporation in the same way it does during the summer. But the water loss is only about a quarter-inch on average during a 24-hour period when the pool is not in use.
Studies confirm that covering a pool can reduce evaporation by up to 95%! That's big water savings! A swimming pool cover traps the vapors and the heat from escaping. Not only can a swimming pool cover can keep more water in the pool, but it can also keep more heat inside the pool.
This will vary depending upon several factors including: weather, if the pool is covered or not, bather load, and if it is heated or not. With pools that are covered, a good rule of thumb is that they should not have to be refilled more often than once every 2 weeks.
A sinkhole can occur whether you have an inground pool or an above-ground pool. A pool that is allowed to leak into the foundation underneath can lead to a very large, very dangerous sinkhole. In fact, leaking water is the main cause of a sinkhole. Sinkholes start developing a long time before they actually appear.
When should I drain my pool? Pool industry experts recommend you drain your pool and refill it every five to seven years. No two pools are alike, so there is no set number at which you must drain your pool.
Does water evaporate more rapidly in autumn and winter? ... As the temperature of your pool's water gets colder, the differential pressure between the water and the air increases. This speeds up the rate of evaporation. In addition, lack of humidity and wintertime dry air can also increase evaporation rates.
Water is a wonderful molecule and collectively, these molecules seem to be together in the form of water but from the surface of water, some molecules always skip to form vapors. The evaporation decreases at night but it can never be zero.
Pool Losing Water After Heavy Rain
Due to a heavy rainstorm, water loss is more common with vinyl liner pools that can be damaged, come loose, or float to the top. With other types of inground pools, it is vital to get the water level down. If not drained, the water balance will change, causing cloudy water and more.
Structural Issues
The expense of repairing structural damage caused by leaks can be quite high. The pool may develop cracks, and the pool or pool floor may settle into the earth, causing more damage. A plumbing leak might result in mechanical problems with your pool, such as damage to the pumps.
Pumps and motor problems can cause a swimming pool leak. General wear and tear on the pool surface can cause leaks. Broken plumbing beneath the pool deck can saturate the ground. Loose fittings on railings, tiles and other accessories lead to leaks.