The Imnaha is a National Wild and Scenic River that begins in the Eagle Cap Wilderness and flows to the Snake River in Hells Canyon. There are several runs on the Imnaha to consider and the most commonly paddled stretch is from the NF-4260 bridge near Cow Creek to the Sanke River.
The tricky part about doing this run are the shuttle logistics. There are two options.
1. Park at the NF-4260 bridge, paddle down to the Snake River and hike back up to your car. There is a hiking trail along this section of the Imnaha River.
2. Paddle down the Imnaha to the Snake River and then continue down the Snake River to Heller Bar.
Mile 0: Put-in at the NF-4260 bridge just upstream of Cow Creek. The rapids downstream are well spaced out the river generally has a pool-drop style. Class IV paddlers will have no problem boat scouting. Class III paddlers can easily scout or portage by using the trail that follows the trail on the right.
Mile 3.3: The whitewater picks up in the last mile with rapids that come in quick succession.
Mile 4.3: Confluence with the Snake River in Hells Canyon. There are some small campsites here.