Restoration effectiveness monitoring in the lower Columbia River estuary

Since 1999, the Lower Columbia River Estuary Partnership (Estuary Partnership) has invested over $4 million in habitat restoration projects in the lower Columbia River estuary. This funding has contributed to 30+ projects, ranging from riparian revegetation to tidal reconnection with off-channel habitats. In 2008, the Estuary Partnership and partners implemented an Effectiveness Monitoring Program to evaluate the overall success of funded restoration projects. Pilot monitoring sites vary based on restoration activity (e.g., culvert replacement vs. revegetation), ecosystem type (e.g., tidal freshwater wetlands vs. forested scrub/shrub wetlands) and geographic placement within the estuary (salinity intrusion vs. tidal freshwater). We provide an overview of data collection efforts and habitat and fish results from the Program’s first year. Preliminary results include the increased abundance and diversity of salmonids following culvert replacement and tidal reconnection and higher densities of woody plants in reference vs. restored floodplain forests. Evaluation of initial efforts reveals several challenges (e.g., use of sampling protocols in diverse habitats, selection of reference sites, and data analyses to document restoration effectiveness) that the Program will address in future years. Monitoring results will facilitate refinements in restoration activities by the Estuary Partnership and regional partners in the lower Columbia River estuary.