You can find Stoneflies from Chester Dam all the way up to the Lower Mesa Falls. Timing is the key for catching this hatch. If you are getting refusals on a Salmon fly, change up to a smaller golder stone. Caddis and Pale Morning Duns should start hatching any day now.
Looks like the main push of the runoff is here. The Fall River at Chester is reaching flows over 7,000cfs making the river below Chester basically in flood stage. Warm River and Robinson Creek have blown out as well. There is good hiking and wade fishing around Mesa Falls and Riverside campground. Rubberlegs, Caddis Pupa, Rollin Stones and CFO Hummer Stones should produce fish.