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Michigan · Crawford / Roscommon Co.

Au Sable South Branch

🍃 Natural River
Crawford / Roscommon Co. · 40 mi · Class Riffles
Optimal: 100–400 CFS · USGS #04135700
Water temp: 64°F
180 avg
392CFS
5.56 ft gauge height
Optimal
Stable
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
Avg flow: 180 cfsHist. median: 162 cfsUSGS #04135700
Michigan Natural River

About

Wild brook trout conservation efforts since 1985 have restored the Au Sable South Branch to its status as one of Michigan's premier native fisheries. This 40-mile Michigan Natural River flows through Crawford and Roscommon counties at 180 CFS average, with optimal conditions between 100–400 CFS on gauge 04135700. The upper reach from Chase Bridge to Smith Bridge runs narrow and wild through undeveloped corridor, while the lower stretch to Roscommon opens into wider meanders with easier access. Log drives ran the South Branch from the 1870s through 1900, floating white pine down to the mills, but the river has returned to its spring-fed clarity. South Branch Canoe Livery provides access for paddlers tackling the gentle riffles that characterize this system — no true rapids, but enough current to keep canoes moving through the cedar and hardwood bottomlands.

Solunar Fishing Activity
🌒
Waxing Crescent
15% illumination
Poor
Moon overhead
9:09 AM
Moonrise
1:22 PM
Moonset
4:56 AM
Moon underfoot
9:09 PM
Next full moon: May 3111 days
Outfitters
South Branch Canoe Livery
Canoe and kayak rentals on the South Branch
10-Year Flow Patterns
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Your Optimal Range
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Data Quality

River conditions are community-verified. CFS ranges, difficulty ratings, and access points may not reflect every flow level or seasonal change. Always check current conditions, scout unfamiliar rapids, and paddle within your skill level.

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