US Bridges

SR 18 over F ST SE

Good

King County, Washington · 0.2 E JCT SR 164 · Structure no. 0005972A0000000

Built
1958
67 years old, rebuilt 1984
Condition
Good
inspected November 2023
Type
Slab
Concrete
Length
66 ft
1 main span
Daily traffic
25,441
2023 count
Owner
State
State Highway Agency

About this bridge

SR 18 over F ST SE is a concrete slab carrying SR 18 over F ST SE in King County, Washington. It was built in 1958 and reconstructed in 1984, so it is 67 years old, older 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 25,441 vehicles a day, roughly 11% of them trucks, projected to reach 36,741 by 2039. The structure is 66 ft (20.1 m) long and 83 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

CarriesSR 18
CrossesF ST SE
Location0.2 E JCT SR 164
RouteState Highway 18
Coordinates47.30339, -122.22158
Functional classUrban Principal Arterial - Other Freeway or Expressway

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 inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating58.2 US tons
Inventory rating45 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length66 ft (20.1 m)
Longest span63 ft (19.2 m)
Deck width83 ft (25.4 m)
Roadway width82 ft (24.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25,441 (2023)
Projected traffic36,741 by 2039
Trucks11%
Lanes on structure5
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed6.8 mi (11 km)
TollOn a free road
National Highway SystemYes

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$2.7 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 18 over F ST SE built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1984.

What condition is SR 18 over F ST SE 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 SR 18 over F ST SE carry?

About 25,441 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is SR 18 over F ST SE?

The structure is 66 ft (20.1 m) long with a longest span of 63 ft (19.2 m) and a deck 83 ft wide.

Who owns SR 18 over F ST SE?

It is owned by the State Highway Agency.