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diggity_ma

Leaking pond - help!

diggity_ma
17 years ago

Looking for some advice here. 2 years ago we had a 3.5 foot stone retaining wall built at the base of a hill behind the house. We also had the mason build a 2-foot high half-circle basin right in the middle of the wall for a pond. It looks great - only problem is that it leaks! First, we coated the inside of the basin with concrete and smoothed it out. Naturally that leaked - no surprise, since concrete is porous. Despite the fact that the walls are about 10-12 inches thick, with granite stones, mortar and cement, it leaked like crazy. So I bought a gallon of liquid EPDM. That improved things, but not by much. I don't know why, but it still leaked.

So this year I thought I'd fix it for sure. I bought a solid EPDM liner, cut it into pieces (so as to avoid buckles) and glued it back together again in place with contact cement. I then coated the entire thing (especially the seams) with more liquid EPDM. Let it dry for a few days, filled it up with water last night and........ this morning it's empty again! :-(

What seems to have happened is that the liquid EPDM did not bond to the solid EPDM liner. You'd think they would bond, since they are the same material, but they didn't. So the thin film of liquid EPDM (now dried) is detatched from the liner. There is probably a hole somewhere in the liquid EPDM, which then transfers water to the liner, which transfers it out a seam, and then down through the original coat of liquid EPDM, then through the concrete! Aaaargh!

What am I doing wrong, folks? How would you waterproof a concrete basin? This liquid EPDM is expensive, so I don't want to spend any more money on that unless it's the only option. How about tar, or some kind of inexpensive roofing product that I can buy from a hardware store? I know this would probably be toxic to fish, but I'd be happy at this point to wait a few months while it off-gasses before adding fish. Is there any other kind of "goo" that I can schmutz on there that would work better?

(I'd be happy to just use a rubber liner, but that's not an option. First, there would be too many creases and buckles, and second, there is a pipe at the bottom of the basin which runs up to a decorative spigot at the top of the stone wall. If I can ever get the pond waterproofed, I will attach a pump to the pipe for running water. Point being, the pipe sticks out from the wall, so I'd have to cut a hole in the liner to accomodate the pipe. Naturally, that hole would leak like crazy, unless I find some kind of reliable goop to waterproof it with. If said goop is so reliable, I'd rather just coat the whole pond with it.)

Any suggestions?

Thanks!

-Diggity

Comments (28)

  • slook

    with a liner everybody has folds and creases. Once you put plants in its hardly noticeable. Bad idea to cut your liner and then try and glue it.

  • slook

    with a liner everybody has folds and creases. Once you put plants in its hardly noticeable. Bad idea to cut your liner and then try and glue it.

  • slook

    with a liner everybody has folds and creases. Once you put plants in its hardly noticeable. Bad idea to cut your liner and then try and glue it.

  • slook

    with a liner everybody has folds and creases. Once you put plants in its hardly noticeable. Bad idea to cut your liner and then try and glue it.

  • diggity_ma
    Original Author
    17 years ago

    Yeah, apparently. :-)

    If I used a liner, I would have LOTS of HUGE folds and creases, because the pond is rather small (I think 6 feet in diameter, with nearly vertical walls). They would be very difficult to hide. I tried it, and it looked awful.

    Thanks,
    -Diggity

  • mike_il
    17 years ago

    Diggity, A product call CIM will do the job for you. It will bond to the concrete and the pipe and will not leak. The thing would be a spray on liner.
    Mike

  • waterbug_guy
    17 years ago

    Liquid EPDM and solid EPDM are not really the same material as you found out. Like cake batter and cake aren't really the same material.

    Most people want goos to seal their concrete. You should try acrylic concrete sealer and silicone caulk. They don't work either but this seems to be the normal course people must go through.

    And everytime you apply a goo it will work. For awhile. Maybe a week, a month maybe even a couple years.

    After that try the CIM 1061. And you thought liquid EPDM was expensive. Oh, and what fun to work with. However, because you've already smeared a bunch of goo on the wall the CIM won't get a good bond and you'll be ready for the next goo.

    Polyurethane would be next up I think. But since it's difficult to apply you'd be ready for the next step pretty fast. Check out a product called Polyurea.

    Of course you could sand bast the liquid EPDM off first. Shouldn't cost too much more than having the structure torn down and rebuilt correctly.

    Hot tar is used to seal shower pans. You could hire a crew to do this pretty cheap. But the gooed walls will not allow for a good bond and I'm not sure how the hot tar would react with the liquid EPDM. Probably badly.

    Fiberglass would probably be the best bet since once cured it wouldn't require a bond to the gooed wall. Pretty expensive and no fun to work with. Hiring a pro might not be a bad idea given how you got to where you are. Fiberglass might require repairs from time to time depending on thickness applied, climate and other factors.

    After you've done all those things install a EDPM liner and mortar rock over the liner to hide it. Sealing the liner over the pipe is easy. $1 pipe clamp. Cut a round hole in the liner 1/2 the diameter of the pipe. Push the pipe thru. Clamp it.

    After that come back online and answer some "how do I seal my leaking concrete" questions. You'll be blown away that goo will be choosen everytime.

  • jerrie
    17 years ago

    Hello, i have the same problem, my concrete pond started leaking. I ordered some stuff called pond shield epoxy pond coating, it is 69.95 a gallon, it covers i think it said 60 feet. It was like $81.00 with taxes and shipping. It sounds like it will work. The web sight is sales@pondbiz.com Good luck Jerrie

  • gherbert
    17 years ago

    Well, there is a way that has always worked for me. Fill it up with water and sprinkle a little corn meal on the surface of the water. In a few hours the pond will be sealed.
    Regards, Herbert

  • diggity_ma
    Original Author
    17 years ago

    OK, Herbert - you've got my curiosity! How does the cornmeal work? Does it just stop up the leak, kinda like putting black pepper in a leaking radiator? Doesn't it degrade?

    Waterbug guy, thanks for all the info. I'm saving your response for future reference. In the meantime, yesterday I impulsively went to my local HD and picked up some plastic roof cement in desperation. It's another type of goo, basically. Might it be worth a try? At least it was cheap, at $6 and change per gallon.

    Thanks!
    -Diggity

    Here is a link that might be useful: Goo du jour

  • gherbert
    17 years ago

    Diggity,

    Well, that is a good question, I guess that the cornmeal migrates into the leak and seals it. I don't know how long it will last, though my Grandfather sealed a pond in our front yard in Los Altos with it back in... oh must have been about 1965 and that pond held water for years. My Grandfather was Baptist Minister and he used the cornmeal trick to seal leaking baptisteries.
    I sealed my cement ponds by mixing plastic cement with water to a paint like constancy and painting a few coats on. Seems to work fine.

    Regards, Herbert

  • diggity_ma
    Original Author
    17 years ago

    Herbert, that's good to know that plastic cement worked for you. I assume you mean plastic *roofing* cement such as I referenced above? If so, I'll go ahead and try it. Do you have fish? (Wondering if there are long-term toxicity issues that would prevent raising fish).

    Thanks!
    -Diggity

  • gherbert
    17 years ago

    Hey Diggity,

    Nope not roofing cement, plain old plastic cement that is used to mix with with sand and gravel to make concrete. A 90lb bag goes for around eight or nine dollars at Orchard or Home Depot.
    I also got some sort of dry powder water proofing stuff at Orchard several years ago that has fiberglass in it. I mixed that up and painted it on my larger pond before I put the plastic cement on. It seemed to seal pretty well but I did not like the white color. Also, I thought maybe the fiber glass might break loose and hurt the fish. LOL, thinking back that is probably very unlikely.

    Regards, Herbert

  • waterbug_guy
    17 years ago

    Diggity,

    You should save the whole thread. I've read many of these over the years in different chats. They always go the same way although the goos change. Couple of years from now you can have a good laugh after you've forgotten about the time and money spent.

    I'm waiting for someone to suggest pouring clay into the water. Come on people.

    Good to hear you're in the roofing department. Try the plumbing dept next. Lots of goos not meant for the job there.

    Speaking of roofing. When I was young I worked for a roofer.

    Step 1. Remove the layers of goos the homeowner had applied.

    Step 2. Find the leak.

    Step 3. Seal the leak.

    The cost of the goos the homeowner used and our time for removal was almost always more than would have been the charge for just coming out and fixing the leak.

    Homeowners, and many roofers, skip step 2, find the leak. They "think" they know where it is and seal away.

  • diggity_ma
    Original Author
    17 years ago

    LOL! :-)

    Thanks for all the info, everyone. It sounds like what I'm hearing is that any "goo" might work for a while, but in the end, nothing beats a solid liner (except perhaps fiberglass, which does sound appealing and I might investigate the cost of DIY versus having someone do it for me).

    So I guess I'll try my goo-du-jour (roof cement) since I already bough it. When that fails (in a day, a week, or a year), I'll probably swear off goos and either go fiberglass or a liner (and try to hide the liner buckles as best I can). Who knows - I might even try the cornmeal trick, although with my luck, it would probably attract hoards of crows and raccoons. :-)

    Thanks everyone!
    -Diggity

  • ocnative1964
    17 years ago

    one method I have heard of is to put a liner over the cement, then to put a layer of cement over the liner to create a sandwhich, your seams are gone and the liner cannot leak.

  • mybusyfamily6
    16 years ago

    I asked my husband who is a mason what he would use in this case and he said that they make a concrete sealer that works. go to concretesealer.com and check out the sites there. I don't know if the sealer will be good with fish but im sure that someone on one of the sites will know.

  • missa7
    16 years ago

    I was going to say there's got to be something because, after all, ... aren't swimming pools made of concrete & they don't leak?

  • luvbocelli
    16 years ago

    Diggity.where else did you use to post? YOur name sounds familiar and I am trying to hook up with a garden friend that use to come the Keene, NH flower show. I can't remember the name or the site
    \Any help/info would be appreciated!

  • james_ny
    16 years ago

    I think a hydraulic cement is used in pool construction. Probably much more expensive but for a small pond it might be ok.

  • floridadream1
    15 years ago

    Our company had a similiar problem the first couple of times with the liquid epdm. I think you are referring to the guys at epdmcoatings.com. anyway i own a pond repair company and a couple of my guys put it on way too thick and filled the pond after a week. based on how thick they applied it they should have waited three weeks. long story short we have been using the product for three years now an found it not only to be highly effective but the only product to hold up over the years with our clients. Hope this helped. By the way elastomerics and the other cheaper products stay away from they don't hold up to water 365 days a year althgouth they say the products with take standing water. Two very different things!

  • dame
    15 years ago

    I think Liquid EPDM or Liquid Rubber is very effective for Pond Leaks Repair.

    Here is a link that might be useful: Liquid Rubber for Fish Pond Repair

  • Brian_C75
    10 years ago

    I have heard quite a bit about this EPDM. I believe EPDM was originally brought to market for roof coatings and things of that nature. That's great and I can see it transitioning into ponds, etc. However, elastomeric urethanes are designed for secondary water containment. Spray-lining a geo-textile fabric with a polyurea or urethane is HIGHLY effective and is used in much more intense environments for water storage and fisheries. Repairs are done quite easily without having do spray-lining over the surface. There are two part systems that are designed for plugging holes and cracks in waterscapes and ponds. Spray-lining has one of the only truly professional DIY Pond liner kits that is easily repairable, is sprayable and is environmentally friendly.

    Here is a link that might be useful: DIY Professional Pond Coatings

  • Brian_C75
    10 years ago

    Check out this article I just found about DIY pond kits on Squidoo. This is really cool cause I have read a lot about issues with diy kits, leaks, holes, etc....

    Here's the article I found. It's pretty new, but I think it's spot on.

    Here is a link that might be useful: Spray-Lining Koi - Fix or Replace your system

  • User
    10 years ago

    I would stay away from any epoxy solutions, they way over priced and don't cover much. I use thoroseal, you can get it thru most hardware stores, I got mine thru Ace Hardware for $32 a bag, it covers about 250 square feet. There some other products like dry lok which I heard works as well from Lowes.

    Stay away from Pond Armor, it's a rip off and gives you very little coverage.

    Here is a link that might be useful: My pond with thoroseal

  • AllAboutKoi75
    9 years ago

    That company spray-lining that abc mentions just put out a new product called seal tite. It's an elastomeric coating that is less than pondarmor and is much thicker. It makes a great waterproof coating that is hard to puncture as well as sealing out harmful chemicals like Lyme.

    Check it out

    Here is a link that might be useful: Cement Sealer / Thick Pond Coating

  • frugalgardener
    9 years ago

    Thanks Waterbug guy! You are so right and I laughed until tears ran down my face.