Just did a quick double check on Google maps and through the street view feature was able to verify that this is the south lift bridge in Joliet and am also happy to say it's still in use.
That is the old Chicago Rock Island & Pacific bridge and although the Rock Island went belly up in 1980 the bridge is still in use by CSX that owns the line to Lasalle Il (IIRC) and is also used by Iowa Interstate.
It has been reduced from double track to single track but so has most of the former Rock Island west of Joliet.