East Fork Potlatch: Bob’s PALs

The Clearwater Soil and Water Conservation District, in partnership with Idaho Department of Lands and the Palouse-Clearwater Environmental Institute, will restore and enhance instream habitat complexity and floodplain connectivity by constructing hand–built Post Assisted Log Structures (PALS) and Beaver Dam Analogs (BDAs) in the East Fork of the Potlatch River from the Latah -Clearwater County line to the bridge just above the confluence with Bob’s Creek, and including the lower 0.2 miles of Bob’s Creek. The work will treat 0.6 miles of high priority steelhead habitat within a project area that includes 0.8 mile of the East Fork of the Potlatch River and the lower 0.2 miles of Bobs Creek.

The Potlatch River has been identified as a high priority watershed for steelhead restoration and the East Fork Potlatch subwatershed has been identified as a “Tier 1” stream for implementation of Restoration Projects in the Potlatch River Watershed Management Plan 2019 Amendment (Latah SWCD 2019, Latah SWCD 2007, NMFS 2017). The 2019 Plan Amendment identifies instream habitat complexity and low winter water temperatures as limiting factors for steelhead production in the mainstem of the East Fork Potlatch. Adding woody structure, such as PALS and BDAs, to streams increases stream channel complexity, creates refugia and hiding cover, improves pool habitat, adds sediment heterogeneity and reconnects channel to the floodplain. Activation of floodplains decreases summer temperature and increases winter temperatures by storing groundwater. Notably, the structures will establish stable sites for beaver, already present in the area, to maintain natural dams. The structures will create at least 30 pools and promote floodplain connectivity along approximately 0.6 miles of stream.