Water exerts about 1/2 pound of pressure for every foot of water depth on the pond bottom. So, a pond bottom has to be sealed better than a marsh bottom.

Typically it's recommended that the whole pond basin be compacted with a sheepsfoot roller in 6" lifts, for a total of 4 lifts.

Just like a bathtub, all you need is one drain hole not plugged and the whole pond will drain out.

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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).