I got some beta for you.... I ran westy on 12/23/03. There was an ice dam below the first easy rapids, but above skull in the flatwater where the canyon gets steep. The ice wasn't thick enough to risk walking on, but was way thicker than we could break through. We ended up having to climb completely out of the canyon (about 300 verticle feet I think) and then back down again. The portage was around a 1/4 mile of river total, but took us about 3 hours because we had to use throwbags to pull the boats up steeper sections. It was an epic day, but I just got back from the Rio Santa Maria in Mexico and that was much more of an epic day if you're looking for one. Kayaking in the winter can be as fun as in the summer if you go looking.
Joe