You know, here in Montana we have several dozen "Rock Creeks".
Of course the most famous Rock Creek is just east of Missoula, and has an excellent salmon fly hatch in late May early June. I'd be happy to take any GCA folks floating and fishing during that hatch.
Another famous, or should I say infamous Rock Creek, is about 100 miles west of Missoula and drains into the Clark Fork River. It is the proposed site of a large mine that would be adjacent to, and beneath the Cabinet Mountain Wilderness Area, a pristine part of the world, home to some of the few grizzly bears in the lower 48 states.