Recommendations for liner patch

[YShahar]

Well, I suppose it was inevitable...I finally found a couple of holes in my liner up by the stream. I'm not sure these were made by an animal with sharp nails or a rock, but I'm betting on a rock. I've got a 2 cm-long tear, and a bit below it, a much smaller puncture. For now, I've taken the rocks out and raised the liner so that the larger tear isn't exposed. The smaller one is still below the water line, as it's going to take a bit more deconstruction of the stream to expose it.

So... what do you folks recommend for patching? There are a few patch kits on Amazon, such as this one:

https://www.amazon.com/Cofair-PLKIT-Tite-Liner-Repair/dp/B009A2EATG/

And seam tape which I could use to make a patch out of an offcut of EPDM:

https://www.amazon.com/Tite-Seal-PLST325-Adhesive-Double-Sided/dp/B00AN8BX4Q/r

These will ship here, though they'll take up to a month to arrive. First off, which would be the better solution? Second, is there something I can do in the short term (a bit of silicon, perhaps)?

 

[addy1]

Bummer

When I have had a leak, I used some pl roofing goop

Smear it on the liner, front and back, cut a piece of liner squish it tight, front and back. Put more pl under the entire liner patch, squish, put pl around the entire edge so no water can sneak under. Let it dry some. I did this to a hole I put in my 1000 gallon stock tank (a opps with the bucket teeth while moving it), fixed it many years ago, still holding. Also a few opps places on some of my smaller pond liners.

 

[JRS]

I used the first kit on a reinforced PVC liner I cut with a sharp rock. Used the PL to seal around the edge of the patch for insurance.

 

[GBBUDD]

Hands down use the first . it's single sided self adhering. but make sure your repair patch has rounded corners. so you cave to round them when you cut it . its a memory thing for rubber not sure why but when they are 90 degree corners they have a habit of pealing on their own.

And where this will be buried under rock On rock I Suggest patching over your patch . It's in the pond construction forum at the top in the stickies how to seam epdm. many say its over kill i say good bye for the extra 20 minutes i'll never see that repair again.

 

[poconojoe]

Make sure whatever you use that it's compatible with your liner material.
For example: EPDM patches and seam materials don't play well if your liner is PVC.

I think the method that @addy1 Suggested is a good one.

 

[GBBUDD]

You are way better off using a tape and use the pl to caulk the edge to hopefully stop roots from working their way from lifting the patch. pl takes like 7 hours to set and 24 hrs to cure. It's a urethane caulking with is great but it takes for ever to work with. the patch and even primers worse case is it takes 30 minutes to set. it's a contact type adhesive one and done.

 

[YShahar]

Thanks guys! Extremely helpful!

So my first move is to look for the Locktite roofing goop (may or may not find that here). Then I'll buy the patch kit and the sealing tape on Amazon to make a longer-term seal.

The good news is that the tear is in the steam liner, which is still mostly free of rocks. Of course this has me paranoid that somewhere under the large rocks in the pond is a similar tear... But the stream liner has been much more exposed to abuse (not to mention slurping porcupines and prancing rock hyraxes). So it's not as surprising to see a puncture dafka there.

Will post progress!

 

[combatwombat]

How did you discover the tear? Were you monitoring water loss?

 

[GBBUDD]

How did you discover the tear? Were you monitoring water loss?

speaking of tears how's your mends doing..... you used epdm seam tape and caulk ? on your hdrpe

 

[combatwombat]

speaking of tears how's your mends doing..... you used epdm seam tape and caulk ? on your hdrpe

Holding up well. A few that were not properly cleaned before sealing have failed, and I’ll try to redo those ones in the spring. Each one only accounts for maybe 12 oz/day. Probably less.

Only used patching tape on one or two micro leaks before deciding it was too difficult to properly apply. Most of them are simply loctite marine sealant applied to the backside of the liner. Front side would have been better, but was near impossible to locate them without seeing them leak on the back side.

 

[GBBUDD]

For reference was the marine loctite able to be applied while surface was wet?

 

[combatwombat]

For reference was the marine loctite able to be applied while surface was wet?

I'd have to read the label again. I believe it is designed to be applied to a wet surface or even under water. But in my case—applying to the back of the liner—the patch needed to be applied and allowed to set above water level or else the seepage would cause the patch to fail by forming a bulge in the adhesive before it could set up. Don't think it would be an issue if applying to the front side of the liner.

Any use of this stuff as a liner patch is "off label" though because it's specifically designed to be a submersible sealant when held in compression. Like a through bolt on a boat hull, etc.

 

[YShahar]

How did you discover the tear? Were you monitoring water loss?

While hauling (or rather rolling) some big stone slabs into the garden, I noticed that one area up around the stream was a bit damp. And since we've had only hints of the first rains so far, a leak was the likely culprit. I took out the rocks and started rolling the liner back a bit at a time. The underlayment was pretty soaked and I eventually found one smaller leak in the bottom of the liner, and a larger tear a bit higher up.

A lot of the rocks here have sharp bits, which I try to hammer off before using them. But it's hard to get all of them and limestone tends to splinter into more sharp bits when hammered, so I've been careful to use underlayment over the liner. It's possible that one of the rocks was sitting where two bits of underlayment overlapped, and the overlap had become mis-aligned. The rock that I believe to be the culprit did have a few really sharp bits sticking out that I'd missed. That rock is henceforth going to be a landscape rock rather than a river rock!

As far as water level goes, the pond isn't losing much--about 2cm per day, part of which is probably due to evaporation. But a leak in the stream is especially worrisome, since given time it could drain the pond.

 

[Lisak1]

I know it's a bit late for the tears you already have, but we learned to use a scrap piece of liner or underlayment to drag big stones around. Number one, it's easier because you can create a "handle" of sorts and number two - you avoid scraping rock on liner if you're moving them into place. (My hands still hurt thinking about how heavy some of those stones were!)

 

[combatwombat]

@YShahar. Got it. Glad you found it and have a plan to patch in place. We have the same issue here with our local granite, but probably not as bad as unweathered limestone.

But a leak in the stream is especially worrisome, since given time it could drain the pond.

Well the good news is that, with an intake bay, it should be practically impossible to drain the whole pond with a leak in the stream. That's assuming you used a single liner for the pond and intake bay—which I don't remember if you did.

When the leak is in the stream, water level can only fall to top of the intake bay before flow is cut off to the pump.