It’s a bit rare that we talk about a BWO emergence this time of year on the South Fork. This last weekend featured an excellent one during afternoons through the canyon. Some of this event can be credited to flow out of Palisades Dam having been stable (just under 12000 cfs) for many days and water temperature beginning to climb. Streamer fishing for rainbows remains effective on the upper river, and rubber leg patterns drifted deep have been attracting fish. Let’s see if the BWO activity lasts through the upcoming warming spell, and an increase in flow out of Palisades Dam could put a damper on it. We’ll keep an eye on the flow, and report significant changes here.
Update 5:30 PM 5-31-16
Releases from Palisades Reservoir will be increased this week for the
cutthroat freshet. Diversions downstream from Palisades Dam should be prepared for
high levels in the Snake River this week and next week. Releases at Palisades Dam
have been approximately 11,500 cfs. Releases will increase each day beginning
tomorrow until reaching 16,000 cfs on Sunday, June 5’h. At that time, the new Great
Feeder head gates will be inspected. If no problems are found with the head gates at
these flows, increases at Palisades Dam will resume, reaching a maximum release of
19,000 cfs on Wednesday, June 8’h. Flows will be slowly ramped down each day
thereafter to return to either 11,500 cfs or to an amount necessary to satisfy downstream
irrigation demand. The increased releases will not affect accrual to unfilled reservoir
water rights. Storage accrued to the American Falls storage water right physically held
in Palisades is simply being moved downstream to be physically held in the empty
physical space of American Falls Reservoir until used by downstream diversions.