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The Springwater Corridor has closed at Oaks Bottom for a major restoration project benefiting salmon and other wildlife. The trail will remain closed through October 31. This is a hard closure: all hours, all days. As with all construction projects, the traveling public is advised to adjust expectations about travel times and travel cautiously and considerately.

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Travel options

Map courtesy of City of Portland Bureau of Environmental Services. Download HiRes.
Alternate routes shown on the map include: 
  • Westside option: The new Sellwood Bridge provides a connection to the newly paved Willamette Greenway Trail. Please note that the Greenway is popular with pedestrians. People on bicycles are advised to adjust their speed and expectations of travel time. 
  • Eastside option: The SE 19th Avenue Neighborhood Greenway connects to the SE 17th Avenue bike lane on the east side. This is a route that has been newly improved by the Portland Bureau of Transportation. 

In addition to those routes, many other options exist in the city’s extensive bicycle network.

Walking trails will remain open within the wildlife refuge. Bicycles are not allowed on unpaved trails.

Oaks Bottom Habitat Restoration

Photo courtesy of City of Portland Bureau of Environmental Services.

The Oaks Bottom Wildlife Refuge is the largest remaining natural area within the Lower Willamette River floodplain. The complex of meadows, woodlands and wetlands offers a unique opportunity for large-scale, tidally influenced floodplain and wetland area to be restored in the heart of the city, at approximately River Mile 16 just north of the Sellwood Bridge. 

During the summer of 2018, the Corps is undertaking alarge-scale habitat enhancement project in partnership with the City of Portland Bureau of Environmental Services and Parks & Recreation. The project will improve hydrology and habitat for protected wildlife species, including amphibians, reptiles, birds, bats and salmon. Right now, migrating salmon cannot safely access Oaks Bottom Wildlife Refuge on their journey to and from the Pacific Ocean because an existing culvert and water control structure blocks fish access into the refuge.

Project Details

Map courtesy of City of Portland Bureau of Environmental Services.
The U.S. Army Corps of Engineers is partnering with the city of Portland to restore 75 acres of wetland habitat by:
  • Replacing the existing culvert under the Springwater Corridor and railroad berm with a larger box culvert;
  • Removing a water control structure;
  • Excavating tidal slough channels; and
  • Removing invasive plant species and replanting with native riparian and wetland species.

Funding for the project is provided by Corps and the city’s Bureau of Environmental Services. Portland Parks & Recreation owns the Oaks Bottom Wildlife Refuge, and will continue to be the steward of the property after completion of the project. Project costs are shared between the Corps (65%) and the city (35%). 

The Continuing Authorities Program and Section 206 of the Water Resources Development Act of 1996 allow the Corps to partner with non-federal agencies to accomplish certain water resources development projects.

Project Updates


Down the trail

A barge will arrive carrying additional construction equipment, including the crane that will be used to position the prefabricated culvert sections.

The rails will be removed so that an open trench can be cut through the berm.

Prefabricated concrete sections will be used to construct the culvert. After installation, the berm will be refilled and the tracks and trail replaced.



Coming soon

Crews will install temporary coffer dams upstream and downstream of the project area to isolate the area and allow construction work to occur. 

A fish salvage team will collect any fish remaining in the wetland and transport them away from the project area and out of harm’s way.

Construction crews will begin to excavate and grade new tidal slough channels to improve hydrology and wetland habitat.

july 9

Springwater Corridor trail closes at Oaks Bottom Wildlife Refuge

The trail closure starts after being postponed a week to accommodate the July Fourth holiday and the Blues Festival. Street teams are onsite to provide reminders and way-finding assistance. The temporary closure will continue as planned through October 31. 

Early july

Preparatory work continues & Major construction begins

The "in water work window" opens July 1 and will run through October 31. As required by state law, the bulk of the work takes place during this time to minimize impact on salmon. 

The contractor continues to move materials and equipment to the site by rail ahead of the trail closure. The early mobilization allows the project to keep moving while keeping the trail open an additional week.

With the partnership of Xerces Society, the project team salvages approximately 230 native freshwater mussels from the wetland and transports them to the Columbia Slough, where they will remain until construction is over.


Early work: Vegetation removal

In preparation for the project, cottonwood and ash trees and other vegetation are cleared from construction areas. Completing this work before the primary bird nesting season, which began in April, ensures that birds built nests out of harm’s way.  

Fewer than 145 trees, mostly wetland species such as Oregon ash and cottonwood, were removed. Many will be reused on site rooas habitat features: larger trees will be used in the channels or as snags, and smaller trees and branches will be built into habitat piles that will provide shelter for wildlife.

A total of 8,500 native trees and shrubs will be installed after construction. 

Short Term Impacts, Long Term Benefits

During construction, the Springwater Corridor Trail will close for up to 120 consecutive days. Directional signage will provide bicyclists and pedestrians with alternative routes around the closure. Walking and biking access to the Oregon Yacht Club floating home community and Oaks Amusement Park will be maintained throughout the project via the Springwater Corridor.

The restoration of Oaks Bottom will provide important habitat for fish and wildlife that are considered "special status," including threatened salmon and over 100 bird species. Improving the connection between Oaks Bottom and the Willamette river will:

  • Facilitate fish passage into Oaks Bottom so that juvenile salmon can access calmer waters to rest and find food;
  • Restore the natural tidal exchange between Oaks Bottom and the Willamette River to improve wetland habitat; and
  • Reduce invasive species and foster growth of native vegetation.

The addition of two wildlife viewing platforms will also increase opportunities for recreational and educational enjoyment of the Oaks Bottom Wildlife Refuge.