US Bridges

SR 520 over 116th Ave NE

Fair

King County, Washington · 0.1 E JCT I-405 · Structure no. 0008591A0000000

Built
1966
59 years old, rebuilt 1997
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
165 ft
3 main spans
Daily traffic
45,466
2023 count
Owner
State
State Highway Agency

About this bridge

SR 520 over 116th Ave NE is a prestressed concrete stringer/multi-beam or girder carrying SR 520 over 116th Ave NE in King County, Washington. It was built in 1966 and reconstructed in 1997, so it is 59 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 45,466 vehicles a day, roughly 3% of them trucks, projected to reach 74,202 by 2039. The structure is 165 ft (50.3 m) long and 57 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesSR 520
Crosses116th Ave NE
Location0.1 E JCT I-405
RouteState Highway 520
CountyKing County
StateWashington
Coordinates47.63189, -122.18597
Functional classUrban Principal Arterial - Other Freeway or Expressway

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 evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.9 US tons
Inventory rating37 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length165 ft (50.3 m)
Longest span61 ft (18.6 m)
Deck width57 ft (17.3 m)
Roadway width54 ft (16.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic45,466 (2023)
Projected traffic74,202 by 2039
Trucks3%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
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$4.2 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 520 over 116th Ave NE built?

It was built in 1966, making it 59 years old in 2025. It was reconstructed in 1997.

What condition is SR 520 over 116th Ave NE 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 SR 520 over 116th Ave NE carry?

About 45,466 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is SR 520 over 116th Ave NE?

The structure is 165 ft (50.3 m) long with a longest span of 61 ft (18.6 m) and a deck 57 ft wide.

Who owns SR 520 over 116th Ave NE?

It is owned by the State Highway Agency.