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North Dakota · Slope / Sioux Co.

Cannonball River

Slope / Sioux Co. · 140 mi · Class I
Optimal: 50–500 CFS · USGS #06354000
160 avg
46.2CFS
2.30 ft gauge height
Below Optimal
Stable
Flow data is live from USGS·Rapid classifications and CFS ranges need community verification··Know this river?
Avg flow: 160 cfsHist. median: 144 cfsUSGS #06354000
Standing Rock Sioux Reservation corridor

About

Hunkpapa Lakota territory for generations before European contact, the Cannonball flows 140 miles through Slope and Sioux counties from prairie headwaters to the Missouri River confluence at Standing Rock. The upper 50 miles through Slope County to Hettinger run as a narrow prairie stream averaging 160 CFS, while the lower 90 miles widen through Standing Rock Sioux Reservation lands. Class I water throughout, with optimal flows between 50–500 CFS on USGS gauge 06354000. Standing Rock Tourism coordinates river access through reservation corridors. The Cannonball gained national attention in 2016 during the Dakota Access Pipeline protests, when water protectors camped along its banks to defend the river and the Missouri confluence from potential contamination.

Solunar Fishing Activity
🌒
Waxing Crescent
15% illumination
Poor
Moon overhead
10:17 AM
Moonrise
2:21 PM
Moonset
6:12 AM
Moon underfoot
10:17 PM
Next full moon: May 3111 days
Outfitters
Standing Rock Tourism
Reservation access permits, cultural tours, river information
10-Year Flow Patterns
See 10 years of flow patterns for this river — historical analysis is a Pro feature.Upgrade to Pro →
Your Optimal Range
Set your personal optimal CFS window per river — custom ranges are a Pro feature.Upgrade to Pro →
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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