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Difficulty III-V
Length 4 Miles
Gauge Boulder River at Big Timber MT
Flow Range 1000 - 5000 CFS
Flow Rate as of: 6 days ago 410 [CFS] ℹ️
Reach Info Last Updated 07/24/2010 12:16 am

River Description

Hells Canyon of the Boulder is a high quality whitewater run set in a spectacular valley.  A bit of flat water leads to a massive rapid that is a portage for most or all paddlers.  A bit more chill water leads to the class IV/IV+ canyon section.  The rapids are often pretty long and continuous, and several have distinct moves to be made to boof or avoid big holes.  We paddled it at 1600 and the rapids were plenty juicy and distinct.  Flows in the 3500 range are rumored to yeild Class V big water rapids that are long, continuous, and connected.  After 5-10 good rapids the whitewater eases off but remains fun to the takeout. . 

Rapid Descriptions


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Paul Heffernan
1 year ago

There are 3-4 new logs across the river in this section. I paddled it at 1400cfs. All wood in this section was new (looked as though the storm the day before was the culprit). Not sure if high water typically clears this section or if logs might remain for a while.

Gauge Description


Directions Description

We have no additional detail on this route. Use the map below to calculate how to arrive to the main town from your zipcode.


No Accident Reports



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