Nope, it's not the ottawa River, and it's not La Maurice (at Trois Rivieres)
The above picture is the bridge over the Ottawa River taken by moi from the Hull side at Lachute 119.25
The above picture is the bridge over La Maurice in Trois Rivieres, also taken by moi at Trois Rivieres Mile 83.5
Clue...
This bridge is on the Trois Rivieres sub that runs from Laval to Quebec City.
In fact, it's between Trois Rivieres and Quebec City....
The above photo shows the centre pier of the bridge in question on which the centre span rotates. Quite massive acutally and was built in the 1860's I believe, though the superstructure was changed out at one time or another.
Another view of the bridge in question....