As you follow the lower Willamette River through the city of Portland you see mostly hardened banks, sea walls and industrial sites that line both shores of the river. But along the east bank of the river, just a few miles south of downtown Portland, you come across a stretch of beach and wetlands and braided channels that reminds us of the landscape through which the lower Willamette River once flowed. A central feature of this nearly natural stretch of watershed, is Oaks Bottom, a 160 acre wetland and wildlife refuge, the closest thing left to the rich wetland habitat that once lined both shores of the Willamette River, where Portland now stands.
This week on Locus Focus we talk with Anne Nelson with Portland Environmental Services, Mark Griswold Wilson - Restoration Ecologist with Portland Parks & Recreation City Nature Division - and Sean Bistoff - the project manager for the habitat enhancement project at Oaks Bottom, who are involved in a project to restore Oaks Bottoms' natural features and functions. For nearly a century the wetlands have been severed from the river by a railroad berm. The plan is to reconnect Oaks Bottom to the river and recreate a salmon nursery in its open water. We look at the challenges of restoring a functioning ecosystem in Oaks Bottom, which like so many urban natural areas, has endured decades of abuse and neglect.
In the summer of 2011, the City Nature Division of Portland Parks & Recreation and Portland Environmental Services will be constructing a large scale habitat enhancement project at Oaks Bottom to benefit wildlife and people. The project will enhance 75 acres of wetland habitat by:
* Replacing an existing culvert with a larger box culvert to enhance fish passage and significantly improve the flow of Willamette River water in and out of the refuge.
* Excavating tidal slough channels and enhancing wetland habitats at the south end of the refuge to provide off-channel refuge for salmon.
* Removing invasive vegetation, such as purple loosestrife, and revegetation with native species to improve wildlife habitat.
* Enhancing opportunities for environmental education and interpretation of the refuge from the Springwater on the Willamette Trail.
Mark Griswold Wilson is an Restoration Ecologist with Portland Parks & Recreation City Nature Division and a neighbor of Oaks Bottom.
Anne Nelson is an Environmental Program Coordinator for the Willamette Watershed with the City of Portland Environmental Services. She works on urban watershed function enhancment projects such as the Oaks Bottom Habitat Enhancement Project, Tryon Creek Confluence Habitat Enhancement Project and Tabor to the River. For more information on this work please see: www.portlandonline.com/bes/watershed/willamette
Sean Bistoff has worked at the City of Portland Environmental Services since 1998, and has worked on a variety of projects including environmental monitoring and sampling, permit and development application review, and land acquisition and floodplain restoration in Johnson Creek. Sean is currently the design phase project manager for several wetland restoration projects, including the Oaks Bottom Habitat Enhancement Project. Sean's education is in Water Resources and Geology.
- KBOO