P-9 Ellis Ditch Closure/Reconnect

Project Narrative

The project closed P-9 and the Cross Ditch that comes from Patterson/Big Springs Creek. The elimination of the P-9 Diversion and Cross Ditch removed an existing passage barrier in the Pahsimeroi providing 27.7 cfs instream through the dewatered reaches in the Pahsimeroi, Big Springs Creek and the two reconnected smaller tributaries. Diversions were closed which resulted in two reconnected systems and in-stream flows in two flow limited systems. Improved and reduced water use will provide for more instream flows.Existing barriers in the Muddy Springs Creek, Duck Creek and Big Springs/Patterson Creek were removed. Patterson/Big Springs Creek was reconnected with Duck Creek. Muddy Springs was reconnected with the Pahsimeroi.The results of this project will enhance and improve passage in the Lower Pahsimeroi River. The removal of the Cross Ditch will reduce sediment and reduce temperatures for water going into the Pahsimeroi improving habitat and spawning for ESA listed steelhead and salmon. The reconnection of Muddy springs will provide access to an additional two to three miles of habitat and provide cool water for the Pahsimeroi. Passage and spawning habitat for steelhead and resident rainbow will be improved in the Patterson/Big Springs Creek. The combination of the barrier removals and reconnects will provide approximately four miles of passage.