Also, there aren't any 20 foot deep holes from the Whirlpool down. I only know of 2 spots on the river that are that deep, and they are both above Whirlpool. There are some real deep long bends, which don't typically hold a lot of fish. The RR Trestle is pretty deep, but the deepest part of it can't really be fished due to super-heavy current. Find some outside bends, and try bottom bouncing. Or drop back plugs a little out from a bank that drops straight down, and see what you can find. Watch out for wood.
Ausable Whirlpool drift boat to Oscoda question...
