I don't want to use liner for my 2 acre pond, because when I step into water I like to stand on dirt rather than plastic.

I don't know yet the soil situation on the property I will be buying. But assuming the worst, that it is somewhat sandy and doesn't hold water well, will I be able to apply a cocktail solution with:

--A layer of bentonite on the bottom, and
--A layer of clay soil on top, then
--Compact the whole surface

To ensure a water-holding pond that will allow plants and fish and a whole ecology to thrive?

Robert,
I believe your project should start with locating a respected and experienced and successful pond builder in your area. Pay them to visit your property and evaluate your proposed pond site. There are too many unknowns for anyone to advise you about clay, bentonite, or a liner. Start thinking about a budget. Depending upon how much dirt has to be moved, what materials have to be hauled in and the manpower required, a 2 acre pond could run from $10K to $50K. My third attempt to seal my 1 acre pond used 280,000 pounds of sodium bentonite. That's 6 cable dump trucks full. I'm still not convinced it's fixed. A vinyl liner seemed too expensive when I started this journey, but now I'm wondering....

Talk to Tom Hudson, TJ "teehjaeh57" here on the forum about SoilFlock Polymer sealant. I would pick that over bentonite. And I will when I dig the next pond on my place.

Agree leaky pond is not good. Wouldn't want to be in that situation. Good luck to your effort.

$50K is about the budget I have set for a 2-3 acre pond. So money is not a big issue. And I will indeed find a pond specialist when the time comes. I am just doing research ahead of time for my own understanding. My goal for this project is to create a NATURAL environment. I hope to avoid going down a path that does not achieve such.

Can a lined pond have an ecology going by itself without owner attention after the initial setup -- like a natural lake? Attention meaning things like pumping/filtering, continuous stocking of fish, feeding the fish, etc. My impression is dirt/soil is the foundation of an ecology -- dirt leads to plants, which leads to insects, which leads to small fish, which leads to big fish...

Or, will this work: A lined pond, with 1' of dirt, maybe even 2', on top of the lineer.

Robert,

Have you priced Bentonite and/or a good 3 acre pond liner installed in your area ?

Hi Robert

Welcome to the forum. Last time I priced a liner it was $2.50/sq ft delivered and installed. A 3 acre pond at that cost would run $326,000. No clue if price breaks exist for projects that size, or if one can find cheaper pricing than what I quoted, just sharing my limited experience with liners.

Provided the bentonite is high expansion, say 8:1 +, integrating into the top 4" of soil, compacted, then covered with 24" of high plasticity clay in 6" lifts and compacted with a sheepsfoot roller is the common recommendation from pond building professionals I know. I'd say this is a great path to follow if you suspect your soils are inadequate for sealing a pond. However, if you already have access to high plasticity clay, the bentonite addition is superfluous - the clay liner itself should provide the seal your pond needs. 2' of good clay is typically all that's needed if compacted and worked correctly. Experienced pond builders should be well aware of this process.

If all else fails and your pond is seeping, a polymer can serve as solution. The forum has been using Soilfloc for the past year, and we're seeing around a 90% success rate. I'm happy to help in any manner possible - but hopefully your original construction is performed correctly and we'll never have to resort to Soilfloc education!

Keep your questions coming....what type of fishery are you hoping to establish?

Is clay available in the area? Even if it had to be trucked in?