Au Sable River
★ Wild & Scenic🍃 Natural River🐟 TU Conservation
Crawford / Oscoda Co. · 140 mi · Class Riffles
2,130CFS/ 10.01 ft
Flood→Stable
Water temp: 40°F — Hypothermia risk, wear a drysuit
Optimal: 200–800 CFS · USGS #04137500
Length
Difficulty
Optimal
Avg Flow
Hist. Median
USGS Gauge
National Wild & Scenic River (1984) · Michigan Natural River · Trout Unlimited Conservation
Michigan's most celebrated canoe river — 140 miles of spring-fed water from Grayling to Lake Huron. Birthplace of Trout Unlimited (1959) and home of the legendary Au Sable Canoe Marathon, 120 miles nonstop each July since 1947.
Trip sections
Grayling to Mio — 50 mi, popular family float
Mio to Oscoda — 70 mi, multi-day tripping
South Branch — 20 mi, solitary and wild
Outfitters
Carlisle Canoe Livery
Grayling-based, full service
Penrod's Au Sable
Rentals, shuttles, multiple put-ins
72-Hour Flow Forecast
NOAA NWPSLoading forecast...
10-Year Flow Patterns
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Data Quality
River conditions are community-verified. CFS ranges, difficulty ratings, and trip sections may not reflect every flow level or seasonal change. Always check current conditions, scout unfamiliar rapids, and paddle within your skill level. If you spot an error, use the Improve This River button at the top of the page — your local knowledge is what makes this atlas accurate.