Is It A Pond Leak Or Evaporation? Knowing Can Make A Huge Difference

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Is It A Pond Leak Or Evaporation? Knowing Can Make A Huge Difference

Is It A Pond Leak Or Evaporation? Knowing Can Make A Huge Difference

Pond leakage and seepage aren’t good for you or your pond. It can throw off your pond’s ecosystem and cause your wallet to spring a leak too! There are many reasons why your pond can start losing water, and all of them can lead to you having to fill it yourself every day. This is why it’s important to detect and stop pond leaks as early as possible. A pond leak can turn a low-maintenance pond into a continuous chore. You can prevent that scenario by reading this post to learn all about pond leaks. Reading on can tell you if it’s a pond leak or evaporation. 

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Pond Leak Or Evaporation?

If you’re noticing your pond is losing water while your water bill is increasing, it’s probably not evaporation. Evaporation rates change due to many factors such as location, temperature, humidity, wind, and some localized variables. This can make for a lot of different numbers if you search for pond leak or evaporation on the internet. Seeing as how it’s different for every pond, the first thing to do is figure out how many gallons of water per inch your pond has by using this formula:
Length of Pond x Width of Pond x .75 x .0833 x 7.48
Those last three numbers didn’t magically appear. .75 is a typical percentage of the pond area, .0833 is an inch (which is how much water will be lost from your pond every X days), and 7.48 is how many gallons of water are in a cubic foot. Afterward, follow this formula to see how much water your feature should be losing per day:
.5% of your pump flow per hour per day.
Here are the formulas in action! Let’s say you have a 15′ x 20′ pond. 15 x 20 x .75 x .0833 x 7.48 = about 140 gallons per inch of pond surface. This pond is moving 5000 gallons total per hour through your pump(s) every day. 5000 x .5% = 25 gallons. So, with this pump, you can expect to lose about 25 gallons per day to evaporation. Now you put those numbers together by dividing the gallons per inch by the number of gallons you should be losing: 140/25 = 5.6. This means your pond can lose 1 inch of water every 5.6 days because of evaporation. If it’s more than that then you have the answer to if it’s a pond leak or evaporation.

What If It’s A Pondless Water Feature

Let’s say you have a disappearing pondless waterfall or fountain basin with a 5000 gallons per hour pump. It’s a 200-gallon basin and is 2′ (24 inches) deep. 200/24 inches = 8.33 gallons per inch of the basin. In the previous example, this pump was figured to lose 25 gallons per day to evaporation. 25/8.33 = 3. You should expect to lose 3 inches of water per day to evaporation based on the pump size.

What Causes Pond Leakage

It’s probably not evaporation. Pond leakage can occur for any number of reasons, but one is better than the others. Best case the cause is a low liner edge. This means part of the liner edge is lower than the water which usually occurs when the dirt holding it up, shifts. Any other reason may need a pond professional to look at and repair it. Animals or tree roots could dig through the liner, the plumbing could be acting up, or stakes from your recently installed underwater lighting could have pierced it. The hard part is finding the pond leakage cause so you can start the repair process.

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Automatic Fill Valves and Pond Leakage

Automatic fill valves are like a mask- you can’t tell what’s really going on behind it. They can mask a pond leakage problem for a long time before it gets bad enough to notice. You’ll find out when your water bill is much higher than normal. You can test your automatic fill valve to see if it’s covering up any pond leakage. Shut it off for a week periodically throughout the season and see if your pond loses too much water. Read on to learn other ways of troubleshooting for a pond leak.

Troubleshooting Pond Leaks

The first step in how to fix pond leaks is troubleshooting to find the source. The following process works for ponds and pondless water features. Take a measurement of the water loss when the system is running as it normally is over a 24-hour period. Then turn off or unplug any motors and top off the pond or basin to its maximum level. Let it sit for 24 hours (without rain) then mark the new level. Repeat this until the water is gone. If it’s hot and you have fish, add an aerator to keep the oxygen supply up. Relocate the fish to a tub with some pond water in it if the water level continues to drop. If it doesn’t, then the pond or basin is not the cause. So then…

…it may be the plumbing. This is a hard area to check as most of the time it is underground, but any constantly wet areas on your landscape could be a giveaway. The pond leak could also come from a stream if you have one, so check for wet areas along it. If you can’t locate it, you may need to call in a professional to locate the leak.

Stop Pond Leakage Today!

Now you know all about pond leaks! How to fix pond leaks is a little harder to learn and may require an expert, unless it’s a low liner edge. Keep your pond leak free so it can run smoothly and you can enjoy it without worry. While you’re looking at taking care of your pond, why not learn about an automatic dosing system, which can further lower any maintenance. 

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Who We Are

Just Add Water is a locally-owned company that serves the state of Iowa for over 17 years. Our team is very enthusiastic about upgrading the yards and properties for all of our fellow Iowans, and we have the experienced crew to do so!

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I’ve worked with Just Add Water for two water features. They have always been good listeners and eager to get the work up to my specs. The Just Add Water Team is very creative and loves what they do! They take on any challenge, find a solution and get it done!

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