This small river joins the Middle Fork of the Salmon River 18.5 miles downstream of Boundary Creek. You'll need a permit to float the Middle Fork making this creek logistically difficult to do. Rapid River is only runnable the short period of time between when the road to Seafoam Guard Station is open and the flow is high enough.
This rarely run creek is full of blind corners and logjams so careful boating is important.
Mile 0: Put-in near the confluence with Float Creek. This is near Seafoam Guard Station.
Mile 11.1: Hardscrabble Creek enters from the left side. The river drops at 146 feet per mile soon after.
Mile 13.2: Rapid River joins the Middle Fork of the Salmon. You can hike out with your boat or float downstream if you have a Middle Fork of the Salmon River permit.