Did you know? The oldest bridge in the NBI was built in 1697.
Did you know? The oldest bridge in the NBI was built in 1697.
Connecting the data points... literally.
over W MARQUAM BR RAMPS
W MARQUAM INTCHGE
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This bridge has a Fair overall condition rating of 6 out of 9. While it is not classified as structurally deficient, it shows some deterioration that is being monitored.
The bridge carries 28,069 vehicles per day and is 61 years old.
Its sufficiency rating of 47.3 places it below the national average of 63.6.
The NBI records a navigation clearance of 16 feet — the minimum vertical space below the bridge deck. The total height of the bridge structure (including towers, railings, and superstructure) may be higher.
For travelers with bridge anxiety
This bridge may cause some awareness for travelers with bridge anxiety, but has manageable characteristics.
This bridge is 1938 feet long — a longer crossing, over 1 minute.
A standard overpass design with solid barriers on each side.
About 16 feet above ground — standard overpass height.
About 28,069 vehicles cross daily — moderate traffic, some congestion possible.
The deck is 37 feet wide with 2-3 lanes — moderate width.
This bridge crosses over land, not water — no water views below.
This comfort score is designed to help individuals with bridge anxiety plan their travel. All bridges in the National Bridge Inventory are regularly inspected and deemed safe for travel. This is not medical advice — if you experience severe anxiety, please consult a healthcare professional.
Year Built
1965
61 years old
Structure Type
Steel Stringer/Multi-beam/Girder
Total Length
1,938 ft
590.6 m
Deck Width
37 ft
11.3 m
Spans
12
sections between supports
Max Span
156 ft
longest unsupported section (47.4 m)
Traffic Lanes
2 lanes
One-way traffic
Clearance Below
16 ft
navigation clearance under deck
Clearance height compared to familiar objects
Height shown is the navigation clearance below the bridge deck. The total height of the bridge structure (including towers and superstructure) may be higher.
Daily Traffic
28,069vehicles/day
45.50491°N, 122.67442°W
Steel Stringer/Multi-beam/Girder
A steel stringer bridge uses parallel steel beams (stringers) to support the deck. This is one of the most common bridge types in the US, valued for its simplicity and strength.
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Data from the National Bridge Inventory (NBI), maintained by the Federal Highway Administration (FHWA).
Data year: 2025. Conditions may have changed since the last inspection.
This information is provided for educational and informational purposes only. It should not be used as the sole basis for any decisions related to bridge safety or transportation planning. Always consult official sources and local authorities for the most current data.