I-405 N-e Ramp over Sammamish River

Fair Condition58 years old23,617 vehicles/day

Location

StateWashington
CountyKing
Location8.7 N Jct SR 520
CarriesI-405 N-e Ramp
CrossesSammamish River
Coordinates47.75606, -122.18486

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 Length709.0 ft (216.1 m)
Max Span108.9 ft (33.2 m)
Deck Width26.6 ft (8.1 m)
Deck Area1750.4 sq m
Main Spans7
Year Built1968

Traffic

Avg Daily Traffic23,617 (2023)
Truck Traffic5%
Lanes On Bridge1
Lanes Under Bridge2

Inspection & Ownership

Last InspectionNovember 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Structure Number0008382C0000000

Nearby Bridges