This was quite the project. The objective: create a drainage pond to capture rainwater and greywater runoff from the existing built structures on the property.
Phase I: the greenest route
We hand dug a 9’Lx5’Wx4’D pond – lost a few shovels, found a few interesting artifacts. Used sodium bentonite as an impermeable layer – in comparison to plastic pond liners, we felt this was the greenest route. After 30+ bags of sodium bentonite and months of testing, the conclusion: we need to use a liner.
Phase II: the path of least resistance
We gave in, bought a pond liner of eBay, and it’s successfully held water since the first day of installation.