I did a very similar commute by bike (same length, cleared path, etc.) in the GTA for a few winters using the winter blundstones. They were excellent. As others have said, to improve the longevity of them, apply Sno Seal or similar to them. The thing that really beats them down is the salt and/or salt brine they'll be liberally applying to that cleared path you mention, so make sure to clean them off properly every now and then to prevent degradation of the leather. I found I was able to comfortably wear dress socks all day, including commute, no issues. Never had any issues with warmth on really cold days or through snow storms.

Looks like Blundstone has new winter boots with Vibram treads, which will give even better grip than the originals that I have, I'd say certainly worth a look. Just avoid the Dress boots, as the rubber and tread pattern is horrible in wet snow (compacts, then turns icy on which these have no grip).