And one on the bottom, no longer floating. (note -- was a bridge engineer in Seattle and did work on the old 520 bridge when we designed the retrofitted post-t

And one on the bottom, no longer floating. (note -- was a bridge engineer in Seattle and did work on the old 520 bridge when we designed the retrofitted post-tensioning it in the late 90's. Among other tasks, I supervised a guy drilling holes in the bottom of the bridge with a concrete corer. )