US Bridges

I-405 over Springbrook/Oakesdale

Good

King County, Washington · 0.6 N JCT SR 181 · Structure no. 0017295A0000000

Built
2009
16 years old
Condition
Good
inspected November 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete Continuous
Length
412 ft
3 main spans
Daily traffic
83,533
2023 count
Owner
State
State Highway Agency

About this bridge

I-405 over Springbrook/Oakesdale is a prestressed concrete continuous stringer/multi-beam or girder carrying I-405 over Springbrook/Oakesdale in King County, Washington. It was built in 2009, so it is 16 years old, younger than the Washington average of 49.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 83,533 vehicles a day, roughly 6% of them trucks, projected to reach 121,565 by 2039. The structure is 412 ft (125.6 m) long and 124 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesI-405
CrossesSpringbrook/Oakesdale
Location0.6 N JCT SR 181
RouteInterstate 405
CountyKing County
StateWashington
Coordinates47.46693, -122.23435
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating97 US tons
Inventory rating58 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length412 ft (125.6 m)
Longest span161 ft (49.1 m)
Deck width124 ft (37.9 m)
Roadway width119 ft (36.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic83,533 (2023)
Projected traffic121,565 by 2039
Trucks6%
Lanes on structure8
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and waterway
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 statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$23.7 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-405 over Springbrook/Oakesdale built?

It was built in 2009, making it 16 years old in 2025.

What condition is I-405 over Springbrook/Oakesdale in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in November 2023.

How much traffic does I-405 over Springbrook/Oakesdale carry?

About 83,533 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is I-405 over Springbrook/Oakesdale?

The structure is 412 ft (125.6 m) long with a longest span of 161 ft (49.1 m) and a deck 124 ft wide.

Who owns I-405 over Springbrook/Oakesdale?

It is owned by the State Highway Agency.