Wow! We have a pier that was made from 2" galvanized pipe and put in service in 1974. We don't have anything corroding like that.

I'd see about driving more pipe into the lake bottom equally spaced from the existing posts, refurbishing the whole pier. I'm assuming the angle iron braces are welded to the pipe? Those should be replaced (or added to) the new pipes. If one is corroded away that badly, the rest can't be that far behind.

It's not going to be a small project.

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