Big River
Iron / Jefferson Co. · 135 mi · Class I–II
586CFS/ 3.83 ft
Optimal
Stable
Optimal: 200–1500 CFS · USGS #07018500
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
135 mi
Length
Class I–II
Difficulty
200–1500 cfs
Optimal
680 cfs
Avg Flow
612 cfs
Hist. Median
#07018500
USGS Gauge
Washington State Park · Missouri State Water Trail

A 135-mile Ozark river flowing through Missouri's historic Lead Belt — past abandoned mines, forested hills, and the bluffs of Washington State Park. The Big River offers gentle Class I–II paddling through a landscape shaped by two centuries of lead mining. Despite its industrial past, the river has recovered remarkably, with clear water, gravel bars, and good smallmouth bass fishing throughout the lower reaches.

Trip sections
Bonne Terre to Washington SP — 40 mi, Lead Belt corridor, mining heritage
Washington SP to Cedar Hill — 40 mi, scenic bluffs, best paddling
Cedar Hill to Meramec confluence — 55 mi, wider river, easier access
Outfitters
Big River Canoe Rental
Canoe and kayak rentals for Big River float trips, Cedar Hill
72-Hour Flow Forecast
NOAA NWPS
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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.