Finding a leak is detective work. Fixing it is usually the easy part.
That surprises people. When a pond is losing water, most folks picture a giant tear in the liner, the whole pond drained, and a backyard torn apart for weeks. Once in a while, sure. But most of the leaks we track down around Greater Philadelphia are small, specific, and fixable in a day or less once we know exactly where they are.
If you haven't found your leak yet, start with how to find a pond leak and make sure it's not plain old evaporation. This post picks up where those leave off: what the repair actually looks like, depending on where the water is getting out.
The edge has settled
This is the big one. If we had to bet on a leak sight unseen, we'd bet on the edge.
Here's how it happens. Over a few years, soil under the rim of the pond settles a little in one spot. Maybe the ground was never compacted well, maybe a heavy boulder slowly sank, maybe a chipmunk got ambitious. Now there's a low point where the top of the liner sits just below the water level. Water wicks over the edge and into the surrounding soil, quietly, all day long.
The fix: lower the water a bit, pull back the stone and gravel at that spot, build the soil back up underneath, raise the liner so its edge sits comfortably above the waterline, and reset the stone. Then we fill it back up and watch.
No patch. No new liner. Just grading.
The stream or waterfall is overflowing
Second most common, and it's sneaky because nothing is actually broken.
Streams and waterfalls are lined channels, and the water is supposed to stay in the middle of them. When leaves, plant roots, string algae or a shifted rock start damming the channel, the water level rises. Eventually it climbs over the side of the liner and soaks into the ground. Your pond loses water, but only when the pump is running. That's the clue.
Fixing this one is mostly cleanup and adjustment. We clear the blockage, reset any stones that moved, and lift and re-tuck the liner edges anywhere they've slumped. Sometimes we rework a section of the stream so the water has a cleaner path. It's the same kind of work we do during a fall cleanout, which is one reason ponds on a regular maintenance schedule have fewer of these.
The skimmer is leaking where the liner connects
Your skimmer is a box set into the side of the pond, and the liner is bolted to the front of it with a faceplate and a seal. That connection is a common leak point. Bolts loosen over years of freeze and thaw, the seal gets tired, or the liner was never clamped evenly in the first place.
If the water level keeps dropping until it settles right at the bottom of the skimmer opening, that's a pretty strong hint.
The repair means lowering the water below the opening, pulling the faceplate, cleaning everything up, and resealing it properly. Done right, it's a permanent fix.
Something in the plumbing gave out
Buried pipes, check valves and fittings can leak too. Usually it's a fitting that wasn't glued or clamped properly when the pond was built, a pipe that froze and cracked, or a shovel from a later landscaping project. (We see that last one more than you'd think.)
The tricky part is locating it, since the plumbing is buried. Once we find the wet spot, though, it's a matter of digging down, cutting out the bad section and replacing it. Most plumbing repairs leave the pond itself completely untouched.
There really is a hole in the liner
It does happen. Roots, a sharp rock that worked its way up through thin underlayment, an animal, a dropped tool. The good news is that a hole in a rubber liner can usually be patched.
To do it right, we lower the water below the damage, clean and dry the area really well, and apply a patch with the right primer and patch material for that liner. A good patch is strong and long lasting. One catch for this time of year: the adhesives want mild temperatures and a dry surface, so liner patching is a warm-day job. If you find a liner hole in December, we may need to stabilize the situation and finish the repair when the weather cooperates.
To find a tiny hole, we'll sometimes put a little dye in still water near a suspected spot and watch where it drifts. Leaks pull the color right toward them.
When it's time to stop patching
Repair isn't always the right call. If a pond has a 20-year-old liner that's cracking in multiple places, edges that were never built right all the way around, and a pump that never matched the waterfall, you can keep patching it forever. Or you can fix the whole thing once.
That's the line between pond repair and a renovation. We lay out how to tell which side you're on in pond renovation vs. pond repair, and our pond liner guide explains what wears out and what doesn't.
We'll always tell you straight which one makes sense. Most of the time, it's a repair.
Why fix it now and not in spring?
Because November and early December are a great window. Leaves are mostly down, the water is cool so fish are calm and not stressed by a lower water level, and the ground isn't frozen yet. A leak you ignore over the winter has months to wash soil out from behind the liner, which can turn a small grading fix into a bigger one. If you're planning to keep your waterfall running through the cold, a leak can also drain the pond while you're not looking and burn up the pump.
How pricing works
Leak repair is quoted after diagnosis, because "my pond is losing water" could be a loose skimmer faceplate or a cracked pipe under the patio. Once we know what we're dealing with, you get a clear price before any work starts. Our warranty page spells out what our workmanship and equipment coverage includes.
We find and fix leaks across Bucks, Montgomery, Chester and Delaware counties and South Jersey. If your pond is dropping faster than it should, visit our pond leak repair page, or skip the reading and Start a Conversation. You can also call us at 215-880-6811. The sooner we find it, the smaller it usually is.