US Bridges

I-5 (hwy 001) NB over Surface Streets

Fair

Multnomah County, Oregon · West Marquam Interchange · Structure no. 08591D001 30012

Built
1966
59 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
1,748 ft
9 main spans
Daily traffic
70,324
2022 count
Owner
State
State Highway Agency

About this bridge

I-5 (hwy 001) NB over Surface Streets is a steel stringer/multi-beam or girder carrying I-5 (hwy 001) NB over Surface Streets in Multnomah County, Oregon. It was built in 1966, so it is 59 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 70,324 vehicles a day, roughly 10% of them trucks, projected to reach 73,900 by 2042. The structure is 1,748 ft (532.9 m) long and 37 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesI-5 (hwy 001) NB
CrossesSurface Streets
LocationWest Marquam Interchange
RouteInterstate 5
StateOregon
Coordinates45.50496, -122.67365
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 geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating14.3 US tons
Inventory rating11 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans9 (+6 approach)
Design loadHS 20
Structure length1,748 ft (532.9 m)
Longest span178 ft (54.3 m)
Deck width37 ft (11.3 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deck16 ft (4.9 m)

Traffic and service

Average daily traffic70,324 (2022)
Projected traffic73,900 by 2042
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesThird level (interchange)
CrossesHighway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$10 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-5 (hwy 001) NB over Surface Streets built?

It was built in 1966, making it 59 years old in 2025.

What condition is I-5 (hwy 001) NB over Surface Streets 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 I-5 (hwy 001) NB over Surface Streets carry?

About 70,324 vehicles per day (2022 count), of which roughly 10% are trucks.

How long is I-5 (hwy 001) NB over Surface Streets?

The structure is 1,748 ft (532.9 m) long with a longest span of 178 ft (54.3 m) and a deck 37 ft wide.

Who owns I-5 (hwy 001) NB over Surface Streets?

It is owned by the State Highway Agency.