Building a Pond With Bentonite and Liner

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I was wondering if anyone has experience building a pond using both a liner and bentonite clay. I was thinking that if you used both it would create a leakproof pond. The plan would be to lay down a layer of bentonite clay, apply a liner on top and then rock work on top of the liner to help keep everything in place
 

mrsclem

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I would be concerned about water collecting between the clay and liner. I guess if you put enough rocks down, it would prevent the liner from floating up.
 
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We had a member , Mitch, who was building a bentonite lined pond.....haven't read any of his posts for awhile though. Wonder where he is ?
 

TheFishGuy

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Does that mean he's no longer a member of this forum ? :(
Nope, his profile is still here so that means he is still a member:


Just hasn't been seen since june 18 2019 I believe......
 
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I was wondering if anyone has experience building a pond using both a liner and bentonite clay. I was thinking that if you used both it would create a leakproof pond. The plan would be to lay down a layer of bentonite clay, apply a liner on top and then rock work on top of the liner to help keep everything in place
There is absolutely no benefit to using bentonite with a liner. Bentonite is used along with a clay based material the bentonite swells when it gets wet thus its fibers that are crossed and mixed together locks as it swells . The Clay also being a material that swells when wet is why it's used but tough clay thats wet and it turns to mush instantly but when it's in a mass is fairly tough. if you want to make something where it's going to last fore ever dig your hole and say one with gradualy sloped sides. Cover the bottom with say 4 or 6" of sand install your liner say epdm. then cover the liner again with 6 inches of sand the liner is protected from uv and anything else and it will last a longgggg time . but is it indestructable no sand is nothing thats you can dig through but leave i be and it will be there a long time
 
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There is absolutely no benefit to using bentonite with a liner. Bentonite is used along with a clay based material the bentonite swells when it gets wet thus its fibers that are crossed and mixed together locks as it swells . The Clay also being a material that swells when wet is why it's used but tough clay thats wet and it turns to mush instantly but when it's in a mass is fairly tough. if you want to make something where it's going to last fore ever dig your hole and say one with gradualy sloped sides. Cover the bottom with say 4 or 6" of sand install your liner say epdm. then cover the liner again with 6 inches of sand the liner is protected from uv and anything else and it will last a longgggg time . but is it indestructable no sand is nothing thats you can dig through but leave i be and it will be there a long time
Wouldn't underlying bentonite heal any holes that might puncture the liner?
 
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No it doesn't migrate its mixed in with the soils if you did the liner with a clay and bentonite on the liner it could . trying to rely on a water proof layer below the liner could create a different issue . That being when water gets under a liner it can create what is called a hippo the water gets under and the pressure raises the liner looking like a hippos back surfacing .
 
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No it doesn't migrate its mixed in with the soils if you did the liner with a clay and bentonite on the liner it could . trying to rely on a water proof layer below the liner could create a different issue . That being when water gets under a liner it can create what is called a hippo the water gets under and the pressure raises the liner looking like a hippos back surfacing .
If the bentonite heals the hole then water would not be able to get under the liner. Plus the liner would be held down by rocks and sand. I think a potential concern is the expandability of the bentonite. Would the bentonite expand or contract enough to cause the liner to tear and or shift rocks?
 
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No. But from what I saw with your pond having 4x4 posts in the pond and a island trying to go with a liner could be beyond a challange
 
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No. But from what I saw with your pond having 4x4 posts in the pond and a island trying to go with a liner could be beyond a challange
You must be thinking of someone else. This post is just a general enquiry about how feasible it would be to build a pond using bentonite and a liner. I am planning to build a small water feature and wanted to design something that was as leakproof as possible. your suggestion to use sand sounds like a good idea. Any other suggestions are appreciated.
 

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