Canadian Fleet Backhauls of Ore to US Ports?

[Guest]

How active is the Canadian fleet in the movement of backhauls of iron ore through the Seaway to US ports? I recall several of those fleets bringing iron ore back into the lakes on return voyages after taking grain down the Seaway. Among the ports where it was once common to see Canadian vessels unloading ore included Conneaut, Cleveland, Detroit, and Indiana Harbor.