SR 20 over Swinomish Chan

Fair Condition54 years old18,383 vehicles/day

Location

StateWashington
CountySkagit
Location9.3 E Island Co
CarriesSR 20
CrossesSwinomish Chan
Coordinates48.45600, -122.52161

Condition Ratings

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

Physical Characteristics

MaterialSteel Continuous
DesignStringer/Multi-beam
Total Length3258.9 ft (993.3 m)
Max Span246.1 ft (75 m)
Deck Width36.4 ft (11.1 m)
Deck Area11025.6 sq m
Main Spans5
Year Built1972

Traffic

Avg Daily Traffic18,383 (2023)
Truck Traffic6%
Lanes On Bridge2
Lanes Under Bridge4

Inspection & Ownership

Last Inspection123
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceHistorical significance is not determined
Structure Number0009107A0000000

Nearby Bridges