Pond Turns Inside Out Druing Heavy Rains

[midngn]

About 2-3 times a year here in GA it rains so hard that it turns my pond liner inside out. My pond is built into a hill and I have had drainage installed to try and move the water out and down past the backyard. It does not seem like it is water under the pond, more like a big air bubble. It pushes a lot of the water out of the pond and it take a considerable amount of water to replace it. Someone suggested lining the bottom with heavy rocks, but the installer does not agree and also says it would be hard to clean. Another koi dealer said I would need to take the liner all out and get under the it to address the air pocket. Has this happened to anyone else? How did you fix it?

 

[poconojoe]

Are you sure it's air that's making the pocket or maybe more like water?
We call it a water hippo when water accumulates under the liner and makes a bubble form in the bottom of the liner.

Next time the water level is low, try to lift the liner and stick a vertical piece of PVC pipe down to the bottom between the side of the liner and soil. The idea is water will take the path of least resistance and instead of forcing the bottom of the liner up, it will travel up through the pipe and out.
Leave the pipe there permanently.

 

[midngn]

That may be difficult to do as much of it is under the rock and cemented in to place. I like the idea, maybe I can carefully tunnel underneath and install a pipe like you suggest?

 

[GBBUDD]

Water or air matters not . The solution is the same and who ever your talking to are not very experienced builders of ponds at least not outside of a 10x10 18"inch goldfish pond. Yes the solution is the next time it rains see where it starts to lift first. This helps but is not critical. You want to give the water a way out from under your liner.and that's as simple as to get some pipe down to that lowest point where the hippo starts. You need to give the trapped water ok ok or air a way out from under the liner. Run the perforated pipe under the liner and up the side of the pond the open pipe is where tge water will take as a path of least resistance. You may need some gravel to balance out the pressure and or some river rocks. As far as cleaning is concerned yea it's a obstacle I hope they can manage.

 

[poconojoe]

That may be difficult to do as much of it is under the rock and cemented in to place. I like the idea, maybe I can carefully tunnel underneath and install a pipe like you suggest?

Not sure what you mean exactly.
I guess you mean all the rock edging is cemented in place?
If so, I see the dilemma.
It might be a bit scary to excavate. You'd have to be careful.
Let us know how you make out.

 

[addy1]

Make sure you have any run off diverted around the pond. Maybe there is one place a lot of rain water runs under the liner.

During my build I would go out with a umbrella and see how the water was running down our slope when it rained. I diverted each place I saw water running towards our ponds.

 

[WaterGardener]

Our pond is also set into a hill on one side. The liner bulged once after a heavy rain when water got under it.

We dug a trench around the side of the pond that is alongside the hill to divert the rain. The trench is maybe 8 inches deep and several feet from the pond itself, so it doesn't detract from the look of the pond and is really not noticable. It encircles the area that we have landscaped by the pond on that hill. We also left the dug out dirt along the top of the ditch to keep water from overrunning the drainage ditch. Once grass grew over it all it wasn't visible.

Haven't had that problem since and it's been 6 years now.

 

[poconojoe]

Good suggestions concerning run-off.
If that's your situation, it won't be such a difficult fix.
Keep us posted.

 

[midngn]

Our pond is also set into a hill on one side. The liner bulged once after a heavy rain when water got under it.

We dug a trench around the side of the pond that is alongside the hill to divert the rain. The trench is maybe 8 inches deep and several feet from the pond itself, so it doesn't detract from the look of the pond and is really not noticable. It encircles the area that we have landscaped by the pond on that hill. We also left the dug out dirt along the top of the ditch to keep water from overrunning the drainage ditch. Once grass grew over it all it wasn't visible.

Haven't had that problem since and it's been 6 years now.

I did try that, maybe helps some. It's only when it rains for 2-3 days straight.

 

[brokensword]

lots of great advice above; the effort would be worth it and you could worry a lot less.

 

[WaterGardener]

Larger trench?