David Daruszka posted three photos with the comment:
Union Pacific (former C&NW) Root River Bridge in Racine, WI. The bridge was designed as a moveable swing bridge, but never used as one. The river traffic never materialized.David Daruszka It was known as the C&NW "Old Line" that ran to Milwaukee. The UP downgraded it to single track and it still carries freight, primarily coal for a power plant.
This bridge is so massive that it looks too large for its swing pier. This bridge is a very unusual swing bridge because it is a deck truss. Most swing bridges are through truss bridges or plate girders. It is also a fairly large span for a swing bridge. The double-warren truss configuration is uncommon and noteworthy. [Historic Bridges]
Peter Oberdick It looks like the gearing was installed. I wonder if it was manual or powered.David Daruszka Given the size of the bridge I would assume it was meant to be powered.