Hello, This site has been a gold mine of information for me thus far, and now that I´m working on my first little pond, I thought i´d reach out for some more specific advice.
We are on flat land in the centre of Estonia, and we have started to dig an earth tank/ turkey nest dam. It´s getting bigger every day as we go down through the layers.
We are 6 ft deep, and the layers are 4inches top soil, 2 ft red clay, 2 ft silty gravel, 2ft sand, and then we struck a really nice plastic grey/ blue clay, and i have drilled down into the clay and its at least 3 ft deep.
The top area of the pond is approximately 30 feet diameter, and with sloped walls the bottom is only 6 ft diameter. My question is, would it make sense to make the pond bigger at the bottom (reduce the slope) to excavate deeper into the grey clay, to cover the sand and gravel layers in the pond wall? If so, would 1 foot of clay covering the gravel and sand be enough to seal the pond? Finally, what is the maximum angle that would prevent the clay from sliding off the walls? I´m thinking no greater than 30 degrees, so we can use bentonite if necessary.
I´m trying to think what information i can offer. We are next to a swamp, about 200 yards away, and 3 yards down hill. That´s where we will pump water from. We will also divert rainwater from the roof to the pond.
Cheers for any help you can offer
Last edited by raorm; 06/04/20 05:17 AM.
