River Forest Creek - Willamette River Confluence Floodplain Complexity Project

The project design was completed and the project was implemented during the 2024 in-water work period. The design progressed to full plans, specs & engineering and procurement. All permit submittals were completed and permits were obtained. Construction mobilization, site access, refueling, and equipment staging was all determined in advance of permit submittal and landowner signatures were obtained on necessary permits. The landowner construction agreements were signed. Procurement moved forward, and construction (separate OWEB grant) was completed in the summer/fall of 2024.

The River Forest Creek/Willamette Confluence site, located downstream of the mouth of the Clackamas River, Rinearson Creek, and Boardman Creek, and upstream of Milwaukie Bay which contains the mouths of Kellogg Creek and Johnson Creek, is the next vital link in the “stepping stones of migratory habitat in the Willamette. The proposed project will help cover gaps in off-channel habitat complexity and high-water refuge habitat in this reach of the Willamette River by providing important complex rearing habitat for juvenile fish moving down the lower Willamette River during the winter and spring months.

River Forest Creeks fish use status has not been surveyed, but historically likely included Coho and spring Chinook Salmon, steelhead trout, Pacific lamprey, and resident Cutthroat trout. During the high water of June 2022, a local resident immediately upstream of the project site on River Forest Lake identified a coho salmon in the lake.

Migrating adult salmon and steelhead likely use the confluence of River Forest Creek as high water refugia rearing habitat. Juvenile salmon and steelhead from both the Clackamas River and the Upper Willamette River populations are likely present during much of the year. For example, beach seining studies in the Lower Willamette River have noted juvenile Chinook salmon in every month of the year, with peak densities between January and April when river levels are high. Improving habitat complexity at this key location will provide habitat, including high-water refuge habitat, for these juvenile salmon. Monitoring observations indicate a large number of juvenile Chinook are present in Rinearson Natural Areas restored off-channel habitats just upriver on the Willamette from River Forests confluence.

Currently, the site has minimal habitat complexity: Large wood in River Forest Creeks channel or within the floodplain area is largely absent -- small pieces of wood are present, but there are no large pieces or accumulations consisting of multiple pieces of wood. As result there is no significant pool development. Adding large wood and encouraging pool development at the site will improve hiding and feeding habitat for Upper Willamette juvenile Chinook and other salmonids during those winter and spring months when they are in high abundance.