IMW Lower Columbia FFY 2015 (WDOE)

This project continued as an Intensively Monitored Watershed (IMW) coordinated by the WA Department of Ecology in the Lower Columbia River salmon recovery region concentrating on the Abernathy, Mil and Germany Creek IMW complex, with sub-contractor agreements. The purpose of the Intensively Monitored Watersheds (IMW) program is to evaluate whether and how restoration activities increase salmon and steelhead production. A Before-After Control-Impact (BACI) study design was selected to maximize the ability to detect changes in salmon production as a result of habitat restoration treatments while minimizing the probability of detecting spurious inter-annual effects. This document provides an update on current activities and results from the lower Columbia River IMW stream complex. The lower Columbia River IMW stream complex includes three watersheds – Mill Creek is the control (reference) watershed and Abernathy, and Germany creeks are the impact (treatment) watersheds. Watershed-scale monitoring of fish, habitat, and water quality has been conducted since 2005. Target species of anadromous salmonids are tule fall Chinook Salmon, Coho Salmon, and Steelhead Trout. Consistent with the intended study design, annual habitat and flow metrics were highly correlated among watersheds during the baseline monitoring period. Smolt abundances of Chinook Salmon and Steelhead Trout, but not Coho Salmon, were correlated among watersheds. As a result, a BACI or a Before-After design will be used for analyzing post-treatment data as appropriate. A power analysis suggested that, with 10 years of post-treatment monitoring, detectable increases in smolt abundances will range from 42 to 47% for Coho Salmon, 30 to 52% for Steelhead Trout, and 78 to 99% for Chinook Salmon (a = 0.10, ß = 0.90).

This project continues an Intensively Monitored Watershed (IMW) coordinated by the WA Department of Ecology in the Lower Columbia River salmon recovery region concentrating on the Abernathy, Mil and Germany Creek IMW complex, with sub-contractor agreements. This project goal was to address salmonid distribution abumdance and productivity througth a coordiantion of efforts and activities.