The Quebec_Bridge was quite an amazing structure for its time in Q-City. Unfortunatly, the bridge wasn't designed to eventually have 2 decks. That would have been so great, because there could have been 3 lanes & 1 set of train tracks on each level. It only has a total of three lanes & 1 track.
https://en.wikipedia.org/wiki/Quebec_Bridge#Second_design_and_collapse_of_September_11,_1916
https://en.wikipedia.org/wiki/Quebec_Bridge#Aftermath_of_the_collapse