I've paddled the Saint Louis River and that is good class 3-5 depending on section and flow. It is up near Duluth, in Jay Cooke State park. There is also the Kettle River and the St. Crois. I haven't paddled any of these. If you want to drop me a line I could hook you up with some folks there who might be able to give you some more help.
I've checked out many of the rivers along the north shore around grand maris (Brule,Cascade ect.) and found them to be small to medium volume IV-V
sparsely populated with VIs
certainly kayak worthy
maybe a spinhole here and there
maybe a 12' R2
but hardly anything raftable except for the commercial runs
The guy who wrote the unofficial guidebook just passed on
I cant think of his name
The upper St. Louis is your best bet(class II-III) Pretty much all of the other north shore runs are creeks(class IV-V+) that are way too technical for rafts, although there may be an exception or two with high water. Not too sure about the southern stuff as I spend most of my time on the North Shore. You may also want to look at the Montreal in the U.P. of Michigan which is a fun playboat run anyways. The Vermillion near crane lake in northern minnesota near canada may be okay to raft as well with enough water, although the whitewater sections are somewhat short, but it is more of a wilderness run and the fishing would be good at camp.
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