Yes its a port but not exactly deepwater.
27 ft. Certainly not the deepest port, but still considered "deepwater."
They've been shipping mega loads out of there for more than a century. We were there earlier this month, and it's an interesting place, both industrially and historically.
I can see how Duluth would be an attractive destination for cross-continent trucking, including return loads to Mexico/China.
It's actually a pleasant little town, gateway to the lovely North Shore. I hate to see it ruined.