Troubleshooting Pond Leaks

Step 1: Does The Pond Actually Have A Leak?

Often, the new pond owner doesn’t realize how much water can evaporate from a pond during the dog days of summer.

• Most ponds typically lose 1” to1 1/2” inches of water each week.
• Contractors and homeowners down in the hot, arid southwest, such as Arizona, have reported evaporation levels in excess of 3” a week.

Remember, these are averages.  Some ponds may not experience evaporation levels this high, while other ponds with large pumps pushing high volumes of water, and/or ponds designed with multiple waterfalls with a lot of cascades and splashing, may have evaporation rates much greater than these.

Step 2: Look For Low Edges

• Here’s a little secret.  99% of all leaks are not due to a hole in the liner, but rather water making its way over the edges of the pond, stream, or waterfalls.
• Look for any low edges.  Settling at the pond’s edge is the most common cause of a leak, especially in a new pond.
• Typically, the low edges are found around the stream and waterfall where settling may have occurred after a few rainfalls.  These areas are usually built up during the construction of the pond using the soil from the excavation, and are prone to some settling.
• Look for signs of a low edge.
  • Wet mulch along the edge of the pond or stream.
  • Wet gravel along the edge of the pond or stream.
• You may need to move back the gravel in certain areas to find the low edge.

How To Fix A Low Edge

Low edges can be built back up by simply back filling and compacting soil beneath the liner in order to raise the edge of the liner above the water level.

Step 3: Look For Obstructions In The Stream And Waterfalls

• Check to make sure nothing is causing the leak by restricting the flow of water down the waterfalls or stream.  The pond owner may have adjusted some of the rocks in the waterfalls in order to improve the look of the falls, inadvertently causing some of the water to be diverted over the liner.  We’ve actually had customer’s kids relocate rocks in the streams in order to create a battlefield for their army men.
• Water can also make its way over the edge due to excessive plant or algae growth in the stream or BIOFALLS®.  The water simply gets backed up from all of the plant growth.  Plants and algae should be maintained by trimming them back in order to let the water pass freely.
• All in all, these leaks are extremely easy to fix.  You can save yourself some time down the road by spending a few extra minutes with new pond owners at the time of installation teaching them how to identify and fix minor leaks such as these.

Step 4: Shut Down The Pump

You’ve spent 15 minutes or so following the suggestions listed above and you still can’t find the leak.  What do you do next?  Well, we now have to go one step further and try to narrow things down a little more.

• Turn off the pump and leave the pond for a period of 12 or more hours.
• Revisit the site after 12 hours,  and see if the water level has dropped.

What Does This Determine?

• If the water level has dropped then we know the leak is in the pond.
• If the water level remains the same in the pond then it is assumed that the leak is in the stream.

*This procedure helps save time by narrowing down the source of the leak.

If The Leak Is In The Pond

If the pond’s water level dropped while the pump was turned off, we now know that the leak is in the pond.

• When our crew goes out to fix the leak, we concentrate our efforts on looking for the leak in the pond and completely ignore the waterfalls/stream.
• Before rushing out to visit the site, we need to wait until the water level stops dropping.  This may take a few hours or a couple days, but will help determine the height of the leak.  We have to wait until the water level is no longer dropping.
• Then look at the site and concentrate your search around the perimeter of the pond at the level that the water has stopped dropping.
• If the water level stopped below the bottom of the skimmer face plate you can rule out the skimmer and concentrate elsewhere.
• If the water level is above the bottom of the face plate you should investigate the skimmer.  It may not have sealed correctly, but don’t tear apart the skimmer face plate.

If The Leak Is In The Skimmer

• Investigate the skimmer face plate without disassembling it. If it is 10 years or older check the screws, they may have disintegrated and need to be replaced. This is a service we provide.
• Simply move a few rocks around the front of the skimmer and slide your hand behind the liner.  Feel for wet soil around the opening of the skimmer.
• If it’s bone dry, it’s most likely not the skimmer.
• If the soil is saturated, then the face plate may have not been installed properly and might be the source of the leak.
• Remove the face plate, clean all of the old silicone off the liner, and refer back to the instruction manual on proper procedures for sealing the skimmer face plate to the skimmer.  Hopefully, you’ve solved the leak

If It’s Not The Skimmer

• Investigate the liner for small punctures around the perimeter of the pond where the water level has stopped.
• Unfortunately, the only effective way to find this type of leak is to start moving rocks and gravel and search for the leak by hand and eye.
• The leak, once found, can be easily fixed using Aquascape’s EPDM patch tape.

Example of a shutdown procedure where the leak is in the waterfalls/stream

• If the water level has not dropped over the past 12 hours.
• This immediately tells us that the pond is not the source of the leak.  So, in other words, do not waste your time looking in the pond or the skimmer for the leak…it’s not down there.  The leak is somewhere upstream!
• Turn the pump back on and get the waterfall flowing again.
• First, double check that all of the edges are high, and any stream liner overlaps or liner seams are done correctly.
• Secondly, check to make sure the seal on the lip of the BIOFALLS® was installed correctly and is watertight.
• Don’t tear apart the BIOFALLS® lip!  You can investigate the BIOFALLS® lip without completely disassembling the waterfalls.
• Move a few rocks around the side of the BIOFALLS® and/or remove some soil from the side of the BIOFALLS®, allowing you to slide your hand behind the liner.
• Feel for wet soil around the BIOFALLS®.
• If it’s bone dry, it’s most likely not the seal on the BIOFALLS®.
• If the soils saturated, or you feel water leaking, then the lip needs to be resealed.
• Important Note:  A few things could have caused the leak at the point of the BIOFALL® seal.  Either the seal was done incorrectly, or the liner was stretched or pulled too tight while setting rocks for the waterfalls.  Make sure to give yourself liner slack along the front of the BIOFALLS® to prevent stress on the BIOFALLS® seal.
• Reseal the BIOFALLS® by removing the BIOFALL® Lip.  Clean all of the old silicone and waterfall foam off the liner, and refer back to the instruction manual on properly sealing the BIOFALLS® lip.
• If you have still been unable to find the source of the leak begin to investigate the rest of the stream and the waterfalls.
•  At this point it is most likely a hole that you should be searching for.
• If the waterfall is right off the side of the pond, or only 5’ back from the pond, the most efficient method is to remove the rocks and gravel in the waterfall area and search for the leak by hand and eye. The leak, once found, can be easily fixed using Aquascape’s EPDM patch tape.

Narrowing Down The Leak On Long Streams

• Leaks can also be narrowed down on waterfalls and streams by performing the “pipe test.”
• The pipe test will take a few days to determine the location of the leak, but it will be well worth the effort.
• The pipe test consists of a section of pipe laid on the ground.  The pipe is connected to the pump in the skimmer. The pump is turned on and the end of the pipe is then set at the lowest point in the waterfalls/stream.
• We then either travel back to the pond the next day or have the homeowner call us to let us know if the water level in the pond has dropped.
• If it hasn’t dropped we move the pipe 10 feet further up the stream.  We do this process until we notice the water drop in the pond.  We know that once the water drops, the leak can be found within 10 feet of the pipe.  We can then move the rocks and gravel to search for the leak by hand and eye.

Additional Tips from Aquascape Inc:

Tip 1:You can sometimes determine if the seals on the skimmer and BIOFALLS® are water tight by temporarily moving a few rocks around the front of the filter allowing you room to feel for wet soil behind the liner. 

Tip 2: You may want to save yourself some time down the road by spending a few extra minutes with the pond owners teaching them how to identify and fix minor leaks such as low edges and excessive plant growth. 

Tip 3: It’s difficult to find a leak if the ground is wet from recent rainfall.  Wait to look until dry weather. 

Still unsure & need help?