The advice is sound. Once the pond is pumped dry, the pond can be "dredged" with a long stick excavator - one that has a 60' boom. They are used to clean ditches here. Once the junk has been cleaned out of the pond, bring in clay and spread it out 6"-8" MAX thickness. Then have a sheepsfoot roller drive over it multiple times to compact the clay, repeat the layer, repeat the rolling. You should get 18"-24" thick clay in 3 or 4 lifts that are compacted together with a sheepsfoot roller.

The tracks on the heavy equipment WILL NOT compact the clay enough.

The clay shouldn't be just on the bottom of the pond, it should come all the way up the sides to a point that is higher than the water will be in the pond.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).