The Pahsimeroi River, a tributary to the mainstem Salmon River, contains Snake River Spring/Summer Chinook, Steelhead, cutthroat trout, westslope trout, bull trout, and interior red-band trout.  Work in this contract will address habitat restoration for these species, particularly Chinook and steelhead.

The NOAA Fisheries Spring/Summer Chinook and Steelhead Recovery Plan (2017) identifies limiting factors in the Pahsimeroi River for Spring/Summer Chinook as low stream flows, passage barriers/connectivity, degraded riparian conditions, degraded channel form and lack of complexity, and water quality. Limiting factors for Pahsimeroi River Steelhead populations include reduced flows during critical periods, migration barriers, elevated water temperatures, degraded riparian conditions, and entrainment.  

Habitat restoration and recovery needs for these species include increased stream flows in the main-stem Pahsimeroi and its tributaries. The Custer SWCD has addressed the need to improve flows by working with the Idaho Department of Water Resources and with individual water users to develop water conservation measures, modify existing barriers caused by diversion or culverts, improve riparian conditions by restoring riparian vegetation, and reducing entrainment by screening irrigation ditches to NOAA standards.

Many stream reconnects have been accomplished over the past 15 years. Habitat complexity is lacking in these reconnected streams. Muddy Springs is one of the channels that was de-watered for over 50 years. The reconnect was complete in 2015 and the channel has been fenced off from livestock since 2004. The project will improve habitat forms and processes for juvenile spring Chinook salmon and summer steelhead.  Juvenile salmonid habitat enhancement will be accomplished by providing more habitat complexity in the channel and extensive riparian planting. Project actions will provide overwintering and summer habitat for juvenile fish and address limiting factors for salmonid production in the Pahsimeroi River watershed, such as reduced stream complexity and degraded riparian conditions.  

This contract will also allow for the Custer SWCD to work on planning of projects and coordination with landowners and water users for work that has been identified as a priority by the Upper Pahsimeroi Working Group. Once projects are identified, the District will seek assistance from NRCS or private engineering firms to provide design and assist in implementation oversight on projects. IDFG will design and install any fish screen under a separate contract. (Screen installations are done via a separate BPA project for IDFG’s Screen Shop (2007-399-00).

Projects planned and implemented through this contract are reviewed and ranked for implementation by the Custer SWCD in conjunction with the Pahsimeroi Basin Subcommittee group, which includes the Idaho Department of Fish and Game, U. S. Bureau of Reclamation, Idaho Department of Water Resources, Natural Resources Conservation Service, Trout Unlimited, Idaho Office of Species Conservation, the Corps of Engineers, Custer and Lemhi counties, NOAA Fisheries, US Fish and Wildlife Service, BPA, and private landowners. This group meets periodically to plan and develop approaches to address restoration needs in the Pahsimeroi River and its tributaries. Individual project ranking is completed through the Upper Salmon Basin Watershed Project Tech Team.

Out-year planning work in this contract includes multiple opportunities for riparian fencing and diversion modifications or removals in the Pahsimeroi, Sulpher Creek and Patterson/Big Springs Creek as the Custer SWCD continue to work with landowners to develop these plans. Custer SWCD will continue to work with the Pahsimeroi Subcommittee to identify and prioritize these projects. This effort will be accomplished with Custer SWCD staff time under this contract. Any funding to complete repairs would be developed with BPA support in a subsequent contract.