The Upper Owens River in the greater Mammoth Lakes area is a classic spring fly fishing creek which originates from a pressurized ground water artesian called Big Springs. The river meanders through open grassy meadow for 26 miles with the mid-upper sections flowing through two private ranches until reaching the northern end of Crowley Lake. Void of trees and bushes, the angler here concentrates on approaching the water in a discreet way as to not spook fish instead of worrying about losing your fly on the back cast.

During spawning runs many brown and rainbow trout find their way up the Upper Owens and remain there for some time. In these times anglers can experience some of the hottest fly fishing around. These fish can be found residing in the Upper O throughout the summer. On occasion a cutthroat will make the journey up river to call the Upper Owens its home. The classic hairpin turns, undercut banks and large pools harbor the resident and migrant spawning trout allowing for large numbers of large fish! Streamers pulled by the undercut banks can produce some aggressive takes as the fish appear out of nowhere, this can also filter out the bigger fish.

The whole area is surrounded by the Eastern Sierra to the west and north, and the white mountain range to the east making it a beautiful panoramic valley. The upper O is worthy of being any fly anglers destination for a guide trip.