I talked to a man today who works for a pond liner company. Selling the material and lining ponds to make them hold water is what they do.
He said the idea seems solid to him. They do the same procedure when lining large projects, but use heavier plastic that is much more expensive. He said the theory is the same, and once the plastic is buried it will accomplish the same thing as their product does, and would last a very long time. Some of the ultra heavy material is only cost feasible for small ponds, like for koi or other backyard ponds and pools.
He was a nice guy and seemed very knowledgeable. He said he'd love to sell me their product, but from what I described that my project would be so expensive if I used their $800 + shipping per roll product it would be very expensive and accomplish the same thing, so he suggested that I go with 10 mil, lap it, and cover it with clay like I suggested. I appreciated his candor and honesty, and that he was trying to help me, not just sell me something.
One thing we discussed is that building contractors commonly use 6 mil black plastic sheeting when framing up to pour a slab for a house. Concrete undergoes quite a chemical transformation in the first few days. If building supply grade black plastic is approved by government back loans, and expected to be a msoiture bartrtier indefinitely, then that is a pretty good endorsement. One could only guess how long it lasts, or how long it would last in a land fill. A LONG time, I'm sure.
As far as all the prep work someone mentioned above, it's really simple. My friend will just push the brush into the low water basin and then track his dozer around the water line where we'll put the plastic. We'll also run a small tractor with a blade on the back, so the site preparation won't be that big of a deal. We'll have three front en loaders to dump the clay on top, and once it's deep enough we'll run the small tractor with the blade over it to smooth and pack it.
The guy I spoke with said he would ask around if anyone else at the company had other ideas, which I appreciated. I'll call him back in a week or so, after I've asked at least one more pond liner company their opinion. If everything goes well I hope to start the middle of October.
DS
