Hey Bob…I’m a little cautious about your question since this is your first year ice fishing.
POOL 2 is from the Ford Dam to the Hastings Dam (Lock and Dam No. 2.
Pool 3 is from the Hastings Dam to Red Wing (Welsh) (L&D No. 3)
Pool 4 is from the Redwing Dam all of some 40+ miles to Winona. This includes Lake Pepin.
Ice fishing on the river without some guidance is not recommended by me. There are some bays that freeze over, Red Wing has at least one and there are people fishing ice on Pepin.
Remember the river is moving…and that means changing ice conditions. In fact places on Pool 3 near Prescot WI that were frozen solid last week are wide open today.
The St Croix by Bayport has a “shanty town” that would be a good place to start. Read Turk’s report in the MN/St Croix River forum for an up to date report.
Again the river never sleeps and more so in the winter months.
Good fishing!