US Bridges

NE 4th Street over I-405

Good

King County, Washington · 2.4 N JCT I-90 · Structure no. 0013133B0000000

Built
1987
38 years old
Condition
Good
inspected March 2021
Type
Slab
Concrete
Length
30 ft
1 main span
Daily traffic
7,745
2020 count
Owner
State
State Highway Agency

About this bridge

NE 4th Street over I-405 is a concrete slab carrying NE 4th Street over I-405 in King County, Washington. It was built in 1987, so it is 38 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 7,745 vehicles a day, roughly 6% of them trucks, projected to reach 12,691 by 2040. The structure is 30 ft (9.1 m) long and 144 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesNE 4th Street
CrossesI-405
Location2.4 N JCT I-90
RouteCity Street 405
Coordinates47.6133, -122.188
Functional classUrban Other Principal Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionMarch 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55.7 US tons
Inventory rating42.9 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length30 ft (9.1 m)
Longest span28 ft (8.5 m)
Deck width144 ft (43.9 m)
Roadway width75 ft (22.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,745 (2020)
Projected traffic12,691 by 2040
Trucks6%
Lanes on structure6
Traffic directionOne-way traffic
CarriesHighway and pedestrian
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 statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$399,000 (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was NE 4th Street over I-405 built?

It was built in 1987, making it 38 years old in 2025.

What condition is NE 4th Street over I-405 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 March 2021.

How much traffic does NE 4th Street over I-405 carry?

About 7,745 vehicles per day (2020 count), of which roughly 6% are trucks.

How long is NE 4th Street over I-405?

The structure is 30 ft (9.1 m) long with a longest span of 28 ft (8.5 m) and a deck 144 ft wide.

Who owns NE 4th Street over I-405?

It is owned by the State Highway Agency.