How to Find a Leak in Your Pond or Waterfall?

Ponds and waterfalls aestheticize your property and are considered a happy place for many people. However, this happy place can turn into a ‘troubling place’ really quickly if there’s a water leak in these water bodies. This article will help you find a leak in your pond or waterfall and also help fix them.

Ponds and waterfalls add to the beauty of your homes and can be an absolute treat to look at. Ponds and waterfalls on your property boast of luxury and are definitely the envy of many of your guests. However, as beautiful as they are, they can turn into a nuisance if there’s any sort of water leak in them.

What’s more, the water leak may also run to places you’ve never even imagined; this causes seepage and a disgusting, musty smell. You don’t want that. 

If there’s a doubt that there might be a leak in your pond or waterfall, you must perform a water leak detection as soon as possible. If your water level is lower than expected, obviously the fish aren’t drinking the water; there’s a leak in it! 

Today, we’ll be enlightening you with ‘how to find a leak in your pond or waterfall?’

Reasons Your Waterfall or Pond Might Be Leaking

There might be several reasons why you might think that your pond or waterfall is leaking, here are some of the most common reasons:

  • There might be a leak in your pond liners. Pond liners can cause your ponds to leak if their rubber line is damaged.
  • You might be dealing with a broken pipe or other fittings.
  • You might witness a decline in water levels due to plain old evaporation. Evaporation is the main cause of dropping water levels in your pond.
  • Your water might start to leak over the berm if the liner edge is pushed down.
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Finding Water Leaks in Your Water Bodies

If there’s a leak in your pond or waterfall, you must find it right away before the problem worsens!

Water Vanishing into Thin Air

Like other water bodies, evaporation is very much a thing that can occur in your ponds and waterfalls as well. In your case, evaporation is the process of the water in your pond turning into water vapor and vanishing into thin air. Water losses due to evaporation are normal, and it’s something that you have no control over.

How much water is lost as a result of evaporation depends on the climate of your region. Typically, there’s greater evaporation in hotter regions. Plus, if your water is moving, there’s a greater chance of it evaporating. The amount of water lost is also affected by the size and quantity of your waterfall – the greater the surface area, the more water is evaporated.

During the spring, summer, and fall, ponds with moderate temperatures and high humidity, you should anticipate losing 1″ to 2″ of water every week. That means a typical 11×16 pond with 4400 gallons will lose 40 inches of water each.  

Regardless of the temperature, a 4 x 6 pond with a 20-foot stream and five-foot cascading waterfalls may lose as much as two inches or more every day! So, if it’s evaporation that you’re losing your pond water to – it’s natural, you don’t have to worry about it!

Picturesque scenery of misty river flowing among leafless trees in forest illuminated by sunlight under cloudless sky in daytime

Looking for Leaks around the Edges of your Waterfalls and Ponds

If you’re looking for leaks inside your waterfalls and ponds, starting with the edges and lining of your pond is an intelligent move. We suggest that you carefully inspect the edges of your waterfall while doing your water leak detection for the same reason. 

Sometimes when the soil and gravel settle in your pond or waterfall, it may create low spots that cause water to leak from the edges. While doing this, make sure you look for damp gravel and mud around your water body – this may indicate a leak. When you’re at it, lift the liner up while pushing some soil underneath the edge to raise it. Doing this is most likely to solve your water leak problem if you find the sand and gravel were the cause of your water leak in the first place. 

Splash Test

You may also think that your waterfall or pond is leaking if there’s a ‘splash leak’ in your water body. A splash leak isn’t what you may call a hardcore leakage problem, but nonetheless, it’s still a problem and reduces the water levels inside your waterfall.

To fix a splash leak, all you need to do is adjust a few rocks or debris around the edges of your waterfall, and VOILA – problem solved! 

Water Leaking Through the Back of Your Waterfall

If you see that water is leaking from the back of your waterfall, there might be a build-up of debris or other troublesome matter inside your waterfall. Pond filters do work to clean small debris, but they don’t work with large debris. Sometimes there may be twigs, dead pond plants, leaves, bio ball bags, filter mats or other material that clock up your waterfall, causing it to overflow through the edges or back. 

Skimming your ponds and waterfalls for leave and other debris may be a proactive approach towards tackling this problem. 

Taking It A Step Further

Have you performed your water leak detection test and still no luck in finding a leak? The problem may be much bigger than you actually thought. To rid yourself of this problem, you must shut your water pump off for a day to find the actual source of the leak.

Here’s what you can do to perform an effective water leak detection test.

  1. Turn your water pump off, and fill up your pond/waterfall up to its mouth.
  2. Use a marker or something else that is not washable to mark the water level after filling your pond.
  3. Wait for a day to find out the actual source of the leak.

After a day, observe the water level. If it’s not below the mark, it means that there is a leak in the stream or pipeline from which the water is coming. Check your fittings, pipes, and plumbing for leaks. Fixing your plumbing can be an arduous task; you should look for professional help if you think you won’t be able to do it on your own. 

However, If the water level DOES drop, it means that you have a leak in your pond. 

Finding Out the Source of The Leak

While finding the exact source of the water leakage, allow your water level to drop even further. Remember, you don’t have to switch on the water pump, or all your efforts will go in vain. After allowing your water level to drop, follow these simple steps.

  1. Remove any rocks, debris, pond plants, and other decorative material to reveal the bare structure of your pond. 
  2. Look for holes and damages in the pond liner. If you find a puncture or a hole, patch it right away. After you’re done with patching the liner, place back what you pulled out from your problem. 

If your pond drains up completely, it means your liner has a puncture at its bottom. 

While patching a hole in the pond liner, you must make sure that you are equipped with the right set of tools and materials to patch the water leak. You can contact your pond/ waterfall contractor to enlighten you in regard to the material that is best for patching YOUR liner. Remember that each pond liner is different. One patching material that may be suitable for one liner might not be appropriate for another liner. 

Asking for help when you need it

Have you been unable to detect a leak in your waterfall or pond? It’s time to seek professional help to solve your problem. Finding a leak in a pond is no piece of cake, and there’s no shame in asking for help when you’re in dire need of it. For help, you can call your pond contractors, retailers, or other experts that specialize in providing maintenance services for your ponds and waterfalls. 

Sealing Your Pond Leak

Before sealing a pond leak, all your woody plants, rocks, debris, and other decorative items must be removed from your pond. After that, you must fix all the holes and crevices that you find. 

If you’re looking for pond liners that aren’t punctured easily, flexible waterproof liners, such as polyethylene, vinyl, butyl rubber, and asphalt-sealed cloth, are a great choice.

To prevent treated soil or liner from being washed away, riprap should be used to block areas exposed to running water. To avoid erosion, cracking, and perforation, treated areas that may become exposed and dry due to water level changes should be sealed with 12 to 18 inches of gravel.

A clay blanket can be spread in 6- to 8-inch layers across the permeable area and packed if a source of soil containing at least 20% clay is available nearby. In water depths less than 10 feet, the clay blanket should be at least 1 foot thick. For every foot of water depth over 10 feet, the clay blanket should be thickened by at least 2 inches.

Natural siltation can help ponds that leak a bit to close themselves. Slightly to moderately permeable soil with at least 10% clay content, a wide variety of particle sizes from tiny pebbles to clay, and no exposed rock layer can usually be sealed by disking and packing or concentrating livestock on the site. Where water depth is less than 10 feet, the soil should be disked and packed at least 12 inches thick when mechanically compacted. For water depths more than 10 feet, it should be thicker.


There’s nothing more that hurts a heart more than wastage of water. However, this doesn’t have to be the case for you!

By now, you must have an idea that finding and fixing pond and waterfall leaks is nothing that’s too hard. You can do it on your own; however, if you feel like you need additional help in water leak detection and fixing those leaks, you can contact professional workers to do the work for you. Happy fixing!


How do you find a leak in a koi pond?

Finding a leak in a koi pond is much similar to finding a leak in a regular pond. The first step in locating a pond leak is to determine whether the pond loses water solely when the pond pump is turned on or off. Turn off the main pond pump and continue to measure if your pond is losing water quickly. If the water level continues to fall, the issue is most likely with the main pond liner.

What to do if your pond is leaking?

A leaking pond with water can also be sealed by dumping a bentonite slurry or spreading granular bentonite over the pond’s surface. Because it’s difficult to apply bentonite evenly to the dry pond bottom, this method isn’t always as effective as putting it to the wet pond bottom. If you’re looking for an effective sealant, contact your contractor and see what they have to say about it.

Why is my natural pond losing water?

Evaporation is the most prevalent source of pond water loss, as mentioned above in the article. In most situations, evaporation accounts for roughly an inch or two of water loss every week. If you’re losing more than that, there’s a leak somewhere in your plumbing system, stream, pump, or pond lining, and it’s time to fix the issue!

How much water should a pond lose per day?

Over the course of a day, a pond in the shadow will typically lose 0.5 percent of the gallons pumped every hour. Over the course of the day, a pond in direct sunshine will lose around 1% of the gallons pumped every hour. However, it also depends on the climate you’re living in. Hotter climates vouch for greater water loss to evaporation.