never been myself so i'm not 100% sure but i'm pretty sure i've heard of ppl doing it, so i checked my maps and there are roads/ trails originating from 3 different ways, the way u went which crosses richie falls, if u cant cross as u say (bridge out) it doesn't look like that far a cruise up the river to the lake, map also shows a road that originates from Elliot Lake, and another trail which hooks up to Mississaugi provincial park which would come off Hwy 129, i may be wrong but thought u might be interested