I-405 N-w Ramp over Sammamish R I-405 SR 5

Fair Condition58 years old8,770 vehicles/day

Location

StateWashington
CountyKing
Location8.7 N Jct SR 520
CarriesI-405 N-w Ramp
CrossesSammamish R I-405 SR 5
Coordinates47.75597, -122.18503

Condition Ratings

Overall ConditionFair
Deck7 (Good)
Superstructure6 (Satisfactory)
Substructure7 (Good)
Channel/Waterway8 (Very Good)
Scour Critical5 — Stable for scour

Physical Characteristics

MaterialConcrete Continuous
DesignBox Beam - Multiple
Total Length1469.2 ft (447.8 m)
Max Span108.9 ft (33.2 m)
Deck Width27.6 ft (8.4 m)
Deck Area3761.5 sq m
Main Spans15
Year Built1968

Traffic

Avg Daily Traffic8,770 (2023)
Truck Traffic5%
Lanes On Bridge1
Lanes Under Bridge14

Inspection & Ownership

Last InspectionNovember 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Structure Number0008382D0000000

Nearby Bridges