The old pond had a double ring of serpentine pavers on a shelf to hold the
liner in place. The obligatory lime capstones sat on top of the pavers to
hide them and hold the liner in place. This looked very quaint, but it did
cost me a few gallons for the dirt to support the pavers and this is where I
had some minor slumpage lately.

So I was considering using some 4" timbers held in place with rebar. I would
then wrap the liner over the timber and nail a strip on top of the timber to
hold the liner. But I thought this might put too much pressure on the liner.
I could still cover the timber with my capstones if my construction
supervisor objected. The timbers are PT BTW, but they would be outside of
the liner and I would use some fish safe wood for my nailing strip. I also
thought I might attach my lights to the top of the wood.

Doing without the pavers will allow me 200+ more gallons for the dirt and
possibly 200+ more gallons for the higher water level. Since Koi are a major
reason for the upgrade, more water is good.

I'd like your opinions on the engineering feasibility of attaching the liner
this way (stretching, slumping, shifting rebar) and the loss of the quaint
factor.