Wisconsin River
Marathon / Portage Co. · 430 mi · Class I–II
197CFS/ 6.01 ft
Below Optimal
Stable
Optimal: 2000–15000 CFS · USGS #05401050
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification·Know this river?
430 mi
Length
Class I–II
Difficulty
2000–15000 cfs
Optimal
8,500 cfs
Avg Flow
7,650 cfs
Hist. Median
#05401050
USGS Gauge
Lower Wisconsin State Riverway · Wisconsin Dells

Wisconsin's longest river — 430 miles from Lac Vieux Desert on the Michigan border to the Mississippi River at Prairie du Chien. The Wisconsin Dells section carved dramatic sandstone canyons during glacial lake outburst floods 15,000 years ago. Below the Dells, the lower Wisconsin flows free for 92 miles as one of the longest undammed stretches in the Midwest — a designated State Riverway with sandbars, eagles, and classic canoe camping.

Trip sections
Wisconsin Dells — 5 mi, sandstone canyon, Class I–II
Sauk City to Spring Green — 30 mi, Lower Wisconsin Riverway, sandbars
Spring Green to Muscoda — 30 mi, wider, island camping
Muscoda to Prairie du Chien — 32 mi, Mississippi confluence
Outfitters
Wisconsin River Outings
Canoe and kayak rentals for Lower Wisconsin Riverway trips
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.