I've only installed floating docks for customers. Our dock on the public lake is made from 2" heavy galvanized pipes washed/pounded into the bottom of the lake with wood joists/framework. Since it is on the side of the lake that is not affected by ice, it stays in all year long and has been in the lake for decades.

www.hoosierpondpros.com

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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).