US Bridges

Hy 61SB to Hy 1NB over W Marquam Br Ramps

Fair

Multnomah County, Oregon · W Marquam Intchge · Structure no. 08591A061C00109

Built
1965
60 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
1,938 ft
12 main spans
Daily traffic
28,069
2022 count
Owner
State
State Highway Agency

About this bridge

Hy 61SB to Hy 1NB over W Marquam Br Ramps is a steel stringer/multi-beam or girder carrying Hy 61SB to Hy 1NB over W Marquam Br Ramps in Multnomah County, Oregon. It was built in 1965, so it is 60 years old, older than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 28,069 vehicles a day, roughly 7% of them trucks, projected to reach 38,246 by 2030. The structure is 1,938 ft (590.6 m) long and 37 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesHy 61SB to Hy 1NB
CrossesW Marquam Br Ramps
LocationW Marquam Intchge
RouteInterstate 405
CountyMultnomah County
StateOregon
Coordinates45.50491, -122.67442
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating13.2 US tons
Inventory rating10.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans12 (+5 approach)
Design loadHS 20
Structure length1,938 ft (590.6 m)
Longest span156 ft (47.4 m)
Deck width37 ft (11.3 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic28,069 (2022)
Projected traffic38,246 by 2030
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesThird level (interchange)
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Hy 61SB to Hy 1NB over W Marquam Br Ramps built?

It was built in 1965, making it 60 years old in 2025.

What condition is Hy 61SB to Hy 1NB over W Marquam Br Ramps in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in September 2024.

How much traffic does Hy 61SB to Hy 1NB over W Marquam Br Ramps carry?

About 28,069 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is Hy 61SB to Hy 1NB over W Marquam Br Ramps?

The structure is 1,938 ft (590.6 m) long with a longest span of 156 ft (47.4 m) and a deck 37 ft wide.

Who owns Hy 61SB to Hy 1NB over W Marquam Br Ramps?

It is owned by the State Highway Agency.