US Bridges

SR 18 over SE 240th ST

Good

King County, Washington · 3.5 E JCT SR 516 · Structure no. 0016008H0000000

Built
2002
23 years old
Condition
Good
inspected March 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
123 ft
1 main span
Daily traffic
20,290
2023 count
Owner
State
State Highway Agency

About this bridge

SR 18 over SE 240th ST is a prestressed concrete stringer/multi-beam or girder carrying SR 18 over SE 240th ST in King County, Washington. It was built in 2002, so it is 23 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 20,290 vehicles a day, roughly 14% of them trucks, projected to reach 28,961 by 2039. The structure is 123 ft (37.5 m) long and 40 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesSR 18
CrossesSE 240th ST
Location3.5 E JCT SR 516
RouteState Highway 18
Coordinates47.38686, -122.06003
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.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating70 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length123 ft (37.5 m)
Longest span117 ft (35.7 m)
Deck width40 ft (12.2 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20,290 (2023)
Projected traffic28,961 by 2039
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.9 mi (3 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$2.3 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 18 over SE 240th ST built?

It was built in 2002, making it 23 years old in 2025.

What condition is SR 18 over SE 240th ST 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 2024.

How much traffic does SR 18 over SE 240th ST carry?

About 20,290 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is SR 18 over SE 240th ST?

The structure is 123 ft (37.5 m) long with a longest span of 117 ft (35.7 m) and a deck 40 ft wide.

Who owns SR 18 over SE 240th ST?

It is owned by the State Highway Agency.