US Bridges

S 160th ST over Airport Expressway

Fair

King County, Washington · 0.25 MI S of SR 518 · Structure no. 085813000000000

Built
1970
55 years old
Condition
Fair
inspected May 2023
Type
Box Beam or Girders - Single or Spread
Concrete Continuous
Length
305 ft
3 main spans
Daily traffic
14,500
2016 count
Owner
Local
Other Local Agency

About this bridge

S 160th ST over Airport Expressway is a concrete continuous box beam or girders - single or spread carrying S 160th ST over Airport Expressway in King County, Washington. It was built in 1970, so it is 55 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 14,500 vehicles a day, roughly 12% of them trucks, projected to reach 17,400 by 2041. The structure is 305 ft (93 m) long and 60 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesS 160th ST
CrossesAirport Expressway
Location0.25 MI S of SR 518
CountyKing County
StateWashington
Coordinates47.4599, -122.29787
Functional classUrban Minor Arterial

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.
Substructure7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment6: Equal to present minimum criteria
Operating rating63.2 US tons
Inventory rating48.6 US tons

Structure

Structure typeBox Beam or Girders - Single or Spread
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length305 ft (93 m)
Longest span134 ft (40.8 m)
Deck width60 ft (18.3 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,500 (2016)
Projected traffic17,400 by 2041
Trucks12%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerOther Local Agency
Maintained byOther Local Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$18.6 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was S 160th ST over Airport Expressway built?

It was built in 1970, making it 55 years old in 2025.

What condition is S 160th ST over Airport Expressway 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 May 2023.

How much traffic does S 160th ST over Airport Expressway carry?

About 14,500 vehicles per day (2016 count), of which roughly 12% are trucks.

How long is S 160th ST over Airport Expressway?

The structure is 305 ft (93 m) long with a longest span of 134 ft (40.8 m) and a deck 60 ft wide.

Who owns S 160th ST over Airport Expressway?

It is owned by the Other Local Agency.