Originally Posted by Theo Gallus
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I have read Just Add Water, and I’m wondering if we require a keyway in the dam. I assume not because we’re using a liner?
Keyways (cores) in dams aren't just to seal water in the pond. They also physically lock the dam into the ground it sits on, like a key on axle holding a gear or wheel in place.

Thanks for the clarification. Since I don't have clay, I think I could use some large limestone rocks we have around (6ft x 4 x 3), or build gabion's with smaller rocks.

Does the size of the dam seem large enough? I wasn't able to find a calculator online for this.