Draglines move less dirt in the same amount of time than an excavator. There are long reach excavators out there, some have 70' sticks. Deeper around the shore with a shallow hump in the center is fine- I know of one lake that has a 2' shallow flat area in the middle and the BG use that as their spawning bedding area.

A dam could by built around the pond a couple feet high to keep the muck from running back into the pond. But, don't forget you can dump the muck as far away from the pond as you are reaching into the pond to get it - even further depending where the excavator is located at.

Another reason for draining the pond is seeing where you are working.

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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).