US Bridges

148th St-W Ramp over I-90 Wbcd Ramp

Good

King County, Washington · 1.7 E JCT I-405 · Structure no. 0009266B0000000

Built
1973
52 years old
Condition
Good
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
1,095 ft
7 main spans
Daily traffic
8,050
2022 count
Owner
State
State Highway Agency

About this bridge

148th St-W Ramp over I-90 Wbcd Ramp is a steel continuous stringer/multi-beam or girder carrying 148th St-W Ramp over I-90 Wbcd Ramp in King County, Washington. It was built in 1973, so it is 52 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 8,050 vehicles a day, roughly 5% of them trucks, projected to reach 13,494 by 2039. The structure is 1,095 ft (333.8 m) long and 31 ft wide.

Location

Open in Google Maps
Carries148th St-W Ramp
CrossesI-90 Wbcd Ramp
Location1.7 E JCT I-405
RouteInterstate 90
CountyKing County
StateWashington
Coordinates47.582, -122.14294
Functional classUrban Principal Arterial - Interstate

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 inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans7
Design loadHS 20 + Mod
Structure length1,095 ft (333.8 m)
Longest span195 ft (59.4 m)
Deck width31 ft (9.6 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,050 (2022)
Projected traffic13,494 by 2039
Trucks5%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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$15.6 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was 148th St-W Ramp over I-90 Wbcd Ramp built?

It was built in 1973, making it 52 years old in 2025.

What condition is 148th St-W Ramp over I-90 Wbcd Ramp 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 August 2023.

How much traffic does 148th St-W Ramp over I-90 Wbcd Ramp carry?

About 8,050 vehicles per day (2022 count), of which roughly 5% are trucks.

How long is 148th St-W Ramp over I-90 Wbcd Ramp?

The structure is 1,095 ft (333.8 m) long with a longest span of 195 ft (59.4 m) and a deck 31 ft wide.

Who owns 148th St-W Ramp over I-90 Wbcd Ramp?

It is owned by the State Highway Agency.