The Whitewater River Run Wilderness Boundary to Confluence with Middle Fork Salmon River is a popular river run in Idaho. The ideal streamflow range for this run is between 800 and 3,000 cfs. The class rating for this segment of the river ranges from Class III to Class IV, with some Class V rapids in certain areas. The segment mileage is approximately 14 miles, and the run is known for its beautiful scenery and challenging rapids.

Some of the specific rapids and obstacles that can be found on this run include Pistol Creek Rapid, which is a Class IV rapid that features a steep drop and a tight chute. Another notable obstacle is Devil's Tooth Rapid, a Class V rapid that requires advanced skills and experience to navigate safely.

There are specific regulations that must be followed when running this segment of the river. All boaters are required to have a permit, and there are limited permits available each year. Additionally, all boaters must follow the Leave No Trace principles and properly dispose of all waste.

Overall, the Whitewater River Run Wilderness Boundary to Confluence with Middle Fork Salmon River is a challenging and rewarding river run that requires skill and experience to navigate safely. It is important to follow all regulations and take appropriate safety precautions when running this segment of the river.