Willamette River Bridge, Spanning Willamette River on Oswego Highway 3, Oregon City, Clackamas County, OR
Significance: The Willamette River Bridge (commonly called the Oregon City Arch Bridge) is 745' long with a 360-foot steel through arch of box-girder construction, encased in gunite. The gunite encasement was necessary to prevent corrosion from sulphur dioxide fumes from the paper mills south of the bridge. This is the only gunite-covered bridge in Oregon. The 1921-1922 Biennial Report of the Oregon State Highway Commission praised this bridge as being "the most artistic appearing large bridge in the State."
Unprocessed Field note material exists for this structure: FN-15
Unprocessed Field note material exists for this structure: N873
Survey number: HAER OR-31
Building/structure dates: 1999