St. John's Bridge, Spans Willamette River at US Highway 30, Portland, Multnomah County, OR
Significance: The St. John's Bridge is significant for its design and for its representation among suspension bridges in the Trans-Mississippi West and in Oregon. At the time of its completion, the bridge had the longest span of any suspension bridge west of Detroit. New engineering features introduced in the bridge included the world's tallest steel frame piers of reinforced concrete, constructed in distinctive Gothic arch motif, the first use of lofty steel towers lacking conventional diagonal bracing; incorporation of the longest prestressed steel cable rope strands yet designed; and the first use of reinforced concrete pedestal piles for an anchorage foundation.
Unprocessed Field note material exists for this structure: FN-24
Unprocessed Field note material exists for this structure: N874
Survey number: HAER OR-40
Building/structure dates: 1929-1931 Initial Construction