US Bridges

I-5 over Dearborn ST

Fair

King County, Washington · 0.1 N JCT I-90 · Structure no. 0007565F0000000

Built
1965
60 years old, rebuilt 1992
Condition
Fair
inspected October 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
219 ft
3 main spans
Daily traffic
71,171
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 over Dearborn ST is a concrete continuous box beam or girders - multiple carrying I-5 over Dearborn ST in King County, Washington. It was built in 1965 and reconstructed in 1992, so it is 60 years old, older than the Washington average of 49.8 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 71,171 vehicles a day, roughly 7% of them trucks, projected to reach 103,465 by 2039. The structure is 219 ft (66.8 m) long and 64 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesI-5
CrossesDearborn ST
Location0.1 N JCT I-90
RouteInterstate 5
CountyKing County
StateWashington
Coordinates47.59553, -122.32028
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.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating26.5 US tons
Inventory rating20.4 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length219 ft (66.8 m)
Longest span96 ft (29.3 m)
Deck width64 ft (19.5 m)
Roadway width61 ft (18.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic71,171 (2023)
Projected traffic103,465 by 2039
Trucks7%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$6.6 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-5 over Dearborn ST built?

It was built in 1965, making it 60 years old in 2025. It was reconstructed in 1992.

What condition is I-5 over Dearborn ST 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 October 2024.

How much traffic does I-5 over Dearborn ST carry?

About 71,171 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-5 over Dearborn ST?

The structure is 219 ft (66.8 m) long with a longest span of 96 ft (29.3 m) and a deck 64 ft wide.

Who owns I-5 over Dearborn ST?

It is owned by the State Highway Agency.