If you are making that pond larger, if you don't drain the water first plan on spending 3x more in operating cost to move the dirt than if you were to be digging in dry dirt without the water. The water washes the dirt back out of the bucket, and you cannot contour the bottom of the pond with the water in there.

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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).