Took a run over there yesterday. Marine city and down to the split was fairly clear on the US side. From the DNR ramp in Algonac down past the ferry and on to Deckers was flowing. Not totally but a path pretty much up the middle. Ferry area was quite clear. Don't know about SC.
You know it really hasn't been all that cold but flows from Lk. Huron kept coming down. Satellite view shows quite a bit of ice right in southern Lk. H. yet to come down.