Almost correct. At Sault Ste Marie, there are 3 movable train bridges crossing the upper lock approach canals, as well as the fixed road bridge which is the only connecting highway link between Canada and the USA for over 350 miles in either direction on the US side, almost 500 miles if your starting point is in Canada..Al, it's always raised for boat traffic to pass. It's only lowered when the rubbish train needs to cross or during the summer months trains like the Cape Flyer, from Boston to Hyannis or the Dinner and excursion trains also cross. They are seasonal only. I believe there are two other lift bridges in the USA, this is the only one left in the UP position, the others are always left DOWN and raised for boats.
The swing bridge on the Canadian side is parked parallel to the canal during shipping season and only rotated for rail traffic and the winter season.
On the American side, the lift bridge over the approach to the MacArthur and Poe locks is only lowered for rail traffic as required. The Poe lock handles the Triple A 1000' freighters
The jacknife bridge over the approach to the Davis and Sabin locks is only raised for the rare occasions that the U.S. Corps of Army Engineers requires access to the upper lock area with their work boats. Those locks have not been used for passing freighters for several decades.
Canadian span. International Railroad Bridge (Sault Ste. Marie International Railway Bridge) - HistoricBridges.org
US spans. https://en.wikipedia.org/wiki/Sault_Ste._Marie_International_Bridge