Sealing a pond with steep slopes without liner

[gautprod]

Hello everyone,

I’m currently working on a pond project and I’m facing a challenge. My pond is approximately 8x4 meters (26 X 13 feet) in size and almost 2 meters (79 inches) deep at the deepest end, average depth of about 80 centimeters (32 inches). I was planning to use sodium bentonite as a sealant but due to space constraints, the slopes of my pond are steeper than the max recommended 1:3 ratio (V:H) for using sodium bentonite as a sealant.

From what I’ve read, sodium bentonite is not a good option for me as it tends to creep downwards on steeper slopes. If I were to follow the recommended slope for bentonite, I would have to reduce the depth of my pond to just 67 centimeters (26 inches), which is not good since I live in a region where freezing temperatures are common, thus maintaining a deeper pond is crucial.

I came across a comment on YouTube suggesting to use 10-20% Portland cement mixed with clay or soil as an alternative method to seal ponds with steeper slopes. Has anyone here tried this method?

Please note that I’m not interested in using pond liners, ducks, or pigs for this project. Any other advice or suggestions regarding using natural materials to seal a pond with steep slopes are greatly appreciated!

[coolwon]

What is the sealer going on to?

[coolwon]

They bag common and face brick walls or what ever needs it's face changing in this

country, prior to going over it

It's a mix of Portland cement and water with I am sure sand to give it a filler

property, and make it go further.

As far as sealing a pond would depend if the weight of the water on the walls would

create cracks due to soil movement over time would be a problem.

You would have to research it more.

[BWG]

If banks are solid at start using a liner will be near 100% success rate at modest cost. Using sealers will be problematic and most likely a high failure rate. Concrete construction suitable for your climate will be expensive. Other option is some type of drop in shell. This also will be more cost and limit shape. Is cost your major factor?

[gautprod]

Thank you for the replies. The pond is dry, I've just finished digging it. I have now been in contact with several distributors of bentonite and all of them say the same thing, sodium bentonite is not a good option for me as it tends to creep downwards on slopes steeper than a 1:3 ratio (V:H). Guess I'll need to look for another solution. Cost is a factor.

[Enrgizerbunny]

Thank you for the replies. The pond is dry, I've just finished digging it. I have now been in contact with several distributors of bentonite and all of them say the same thing, sodium bentonite is not a good option for me as it tends to creep downwards on slopes steeper than a 1:3 ratio (V:H). Guess I'll need to look for another solution. Cost is a factor.

You may need some sort of backing just to apply it to, but you could consider something like surface bonding cement. It's a fiber reinforced portland cement product that was originally developed to patch mineshafts when they sprung a water leak. I don't know how well just applying it to soil would work, but it's a consideration.

[Grumpy]

I came across a comment on YouTube suggesting to use 10-20% Portland cement mixed with clay or soil as an alternative method to seal ponds with steeper slopes. Has anyone here tried this method?

Soil cement works to stabilize soil, but does not guarantee a water-tight layer. I have used it to firm up a muddy walkway, and driveway.

A liner seems to be your best bet if you don't want to flatten the slope of the walls.