Au Sable River · access
Northern Lower Michigan, United States · United States
- Grayling / Wakeley BridgeThe classic flies-only water; heavy canoe traffic on summer weekends.
- Mio and McKinley BridgeDownstream water with better brown trout and far fewer people.
- South Branch / Smith BridgeSmaller water holding native brook trout; light rods and short casts.
Licence and rules
Licence and rules. Michigan requires a fishing licence for anyone 17 and older; a nonresident annual licence is the simplest option for a week's trip. The Au Sable has flies-only, catch-and-release reaches marked above and below Grayling, plus a special gear restriction that limits hooks to single-point, no treble. The trout season on most Michigan streams closes at the end of September, which is a hard date, not a guideline.
Season
The Hex hatch in the last week of June is the event; the trout season closes at the end of September
Flow
300–600 cfs at Grayling; stable because the feeders are springs
Because the feeders are springs, the Au Sable stays cold and clear when other Michigan rivers are muddy in April. The dam at Mio smooths the lower river; above it, flows follow rainfall and the river can colour up for two days after a storm. By August the water is often too warm to fish ethically after noon, and the productive hours move to dawn and after dark.