Environmental Services has completed design of the Tryon Creek Confluence Project. Construction is scheduled to begin in summer 2010. Choose the links below to see conceptual drawings of the project.

Site plan drawing

Tryon Creek Channel and Enhanced Floodplain cross section looking south

Willamette River Beach and Bark Enhancements cross section looking north

The project includes stream enhancement of about 900 feet of Tryon Creek, beginning at its confluence with the Willamette River. The work includes removing invasive plants and revegetating with native species on about 3.5 acres. The Tryon Creek confluence area is within the Lake Oswego city limits on land owned by Metro, the City of Lake Oswego and the City of Portland.

This is the second phase of the project. The Oregon Department of Transportation (ODOT) completed phase one just upstream in summer 2008. That work included stream enhancement and modifying the Highway 43 culvert to improve fish passage into the 645-acre Tryon Creek State Natural Area.

Phase two builds on ODOT's work to improve fish and wildlife habitat. Tryon Creek State Natural Area is well suited for coho salmon and steelhead production. This phase will create off-channel habitat as refuge for fish during high flows, and will give fish greater access to the natural area. The natural area is the only state park in Oregon located in a major metropolitan area.

Project Description

The Tryon Creek Confluence Habitat Enhancement Project will:

• Improve in-stream and stream bank habitat quality and complexity for salmon and steelhead listed as threatened under the Endangered Species Act; lamprey, which are listed as a species of concern; and other native species
• Improve floodplain connectivity
• Improve riparian and upland habitat by removing invasives and establishing native plant communities

Budget

This project is funded by the City of Portland Watershed Investment Fund, the Environmental Services Capital Improvement Program and the Lower Columbia River Estuary Program. Environmental Services is pursuing other funding sources and partners. 

Timeline

Project design is complete. Construction is scheduled for summer 2010. Revegetation will occur in the winter following construction. Monitoring will continue for five years after construction and revegetation are complete.

Contact

Kristen Acock, Project Manager - 503-823-7395

Anne Nelson, Project Outreach - 503-823-2584