Austin, C. and LeMoine, M., 2023. Smokehouse Restoration Effectiveness Monitoring Pre-Project Report. Skagit River System Cooperative, Burlington, WA. pp. 18.

Pre-restoration monitoring of Smokehouse Floodplain tidal blind channels separated from
Swinomish Channel by “fish friendly” tidegate styles demonstrated dampened tidal effects and
substantially lower fish use than in reference tidal blind channels along Swinomish Channel. Salinity was
slightly lower inside tidegates than outside and water surface elevations inside the tidegates did not
mirror ungated reference locations. In earlier work, Greene et al. (2012) observed Smokehouse
cumulative juvenile Chinook Salmon density behind Self Regulating Tidegates (SRTs) was eight times
lower than in reference sites. According to Smokehouse pre-project monitoring, 2020-2022 mean
densities of juvenile Chinook Salmon in Smokehouse sites behind SRTs and Muted Tidal Regulators
(MRTs) were 0.36 ± 1.69 (SD) per hectare, versus 127 ± 413 (SD) per hectare to 449 ± 1138 (SD) per
hectare in reference tidal blind channels. Additional monitoring, funding permitting, will occur after dike
setback to evaluate post-project habitat and fish use.