Showing posts with label concrete pond leaks. Show all posts
Showing posts with label concrete pond leaks. Show all posts

Sunday, May 06, 2012

How to Repair a Pond Liner

You are sure you are facing repairing your pond liner. Before you panic, make absolutely sure it is a leaking liner and not another problem that is causing your water level to drop. Check your waterfall, check your hoses, check your spitters. Turn your pump off, fill up your pond. Watch it overnight. Did the level drop? If so, you probably have a hole in your liner. 

The first thing you must do is find that leaking liner. If you can see it, skip the next section. 

Fixing the leak 

If you can see the leak, you have an easy job. Assuming your liner is rubber or EPDM and most are, you can patch it just like a tire. You can buy a patch online and while you are at it, buy a roll of patching material, because whatever caused that liner to leak will most likely do it again. 

45 mil rubber liners rarely leak spontaneously. Something causes it. It could be raccoon toenails, doggie toenails, a falling tree branch, or maybe a piece of statuary with a sharp end fell and penetrated the liner. No matter the cause of that liner leak, repairing it, while not always a clean and easy job, it can be done by anyone with a bit of effort. 

Make sure the liner surrounding the hole is clean and dry. I scrub the liner with the same scrubber you would use for dishes, just make sure there is no soap in it. After scrubbing it clean, rinse it and let it dry. If you are in a hurry, use a hair dryer, but be careful you are connected to a GFI before you use any electrical appliance around water. When the area is clean and dry, apply the patch according to the directions on the package. Your work is done. Fill the pond back up with water. Don't forget the dechlorinator. 

Finding the leak 

Finding a liner leak can be one of the most frustrating jobs on earth. The liner is black, usually dirty and wrinkled. The leak should be right at the water line because water can't leak out below that. Or can it? Here in New Orleans, our water table is only inches below the ground, so often there can be a hole in the bottom of the liner, but ground water pushes the bottom of the liner so a leak could well be on the bottom and ground water is seeping in the pond. 

Pour some milk in the pond. If the water is leaking fast, the milk will make a trail to the leak. But if the water is leaking that fast, you have a huge tear and you can probably see it. 

Pour some fine sand in the water. The sand will follow the water to the leak, but as above, if the tear is that big, you should need no help finding it. 

Sometimes you cannot find the leak no matter how hard you search. I have resorted to this method as a last resort. Pump the pond water out. Remove all fish, plants, pots, lights, etc. Using a wet vac, vacuum the bottom to be sure all the fish waste, leaves, and other organic matter is gone. Rinse and wet vac again. Make sure the bottom is dry even if you have to wait several hours or get that hair dryer out again. When you are positive it is dry, stick a garden hose under the liner and turn on the water. Watch the liner carefully. Soon you should be able to see water coming up from underneath. You have found your leak. Dry it again and patch with patching material. Replace all pots, plants, fish, lights and refill the pond with water. 

It's a good thing rubber liners rarely leak. 

Leaks in concrete ponds 

If your concrete pond is leaking, there is only one relatively cheap way to fix it. Because concrete is brittle and our ground is always moving, concrete is freezing and thawing, concrete is one of the hardest materials to repair. Clean out the crack and use Plumber's Epoxy to patch it. If that doesn't work, call a professional. If the professional tells you he can patch your concrete and guarantee it, doubt it. Doubt it a lot. 

In all my years of pond building, I have never seen a serious concrete crack patched so it will hold water for more than a few weeks. Get your contractors guarantee in writing, get his home phone, his cell phone, his address and his Landscape Contractor's license number. Getting his insurance certificate can't hurt either. 

If your pond is built from recycled swimming pool liner or PVC or visqueen and it has a leak, you must start over again with another liner. Same with pre formed hard liners. Once they crack, they cannot be repaired. 

Luckily ponds rarely leak. But if yours does, you are now prepared. 

All of this and more is included in my How-To pond book, A Practical Guide to Building and Maintaining Your Pond, available  here

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Tuesday, July 20, 2010

Frog pond

I have a 4ft by 3ft frog pond and water won't stay in it for more the 12 hours.I want to keep it filled without using a nylon or any type of liner.Oh and its about 1 foot deep.


Concrete is a difficult material to use. It's brittle and unforgiving. It leaches out lime, so screws up your pH. And when the ground moves, the concrete cracks.
Try bentonite. It's cheap and easy to use. You line the hole with it - it's a clay and holds water.

Thursday, October 15, 2009

Concrete Pond Leaks

I get questions all the time about leaky ponds. Since there are so many kinds of ponds, so many kinds of leaks and so many ways to repair them, I want to spend  a few days talking about leaks.

Let's start with concrete ponds. I do not recommend building ponds with concrete because it is not watertight and is brittle, but many people use concrete, so I get to fix their leaks.

Concrete ponds crack.  It's inevitable. If you have a concrete pond, it will crack.  Plan on it.  I don't care if you use concrete 6 inches thick and 6000 psi. It's gonna crack.  So, now what?

If the crack is hairline, you perhaps can fix it. Maybe. For a short while anyway.  Get some plumbers' epoxy.  Not plumbers' putty. Epoxy.  Make the crack bigger. Dig it out so there is a bit of a V shape, like the dentist does when he fills a cavity in your tooth.  Now make sure the crack is dry and clean.  If you have to, use a hair dryer to dry it completely.

Now mix the epoxy. Put gloves on first because the epoxy sticks on your hands just like it sticks on the concrete. Epoxy comes in a tube and looks like a big stick of chalk.  So unwrap as much as you need and start pinching and rolling it - gloves on, remember.  In a couple of  minutes, the epoxy will get warm. A minute or so after that, it's ready to use.  Smush the epoxy in the crack. Notice the technical term, smush. It's important. Make sure the epoxy is pushed into the crack and smoothed out both in the crack and along the edges.  Wait for it to dry.  The directions on the side of the package will tell you how long that will take.

When the epoxy is dry, refill the pond with water.  The epoxy will not hurt your fish or plants.

I have had some repairs last for several years, some for only several months.  I never guarantee a concrete repair.  Often I will do it free if the pond belongs to a steady customer.  If the customer pays for the service, he expects some sort of warranty and this repair is not good enough for that.

If you can see through the crack in your concrete, you cannot repair it. I don't care who says you can, it is not possible. Find a waterproofing company and have them put a new coating on your pond.  Or just drop a butyl rubber liner inside the concrete pond and start over.