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I-405 over Sunset Blvd (old SR 900)

King County, Washington · rated Fair in the 2025 National Bridge Inventory

United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled August 20, 2026

I-405 over Sunset Blvd (old SR 900) in King County, Washington, is rated in fair condition in the 2025 National Bridge Inventory (as of August 20, 2026).
Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
It was built in 1963 and reconstructed in 1994, making it 62 years old at the 2025 inventory.
It carries about 68,154 vehicles a day (traffic count year 2023).
Its listed owner is the state highway agency.
It is one of 607 of the 1,252 inventoried bridges in King County rated fair (48.5%); 50 (4.0%) are rated poor.
A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.

Component ratings


Structure	Prestressed concrete stringer or multi-beam girder
Length	about 290 ft
Location	0.5 N Jct SR 169
NBI structure number	0006912B0000000
Condition class	Fair

Source: FHWA National Bridge Inventory, 2025 data as reported by the Washington department of transportation.

Bridge	Built	Vehicles/day	Condition
I-90 EB over Sunset Creek	2024	139,482	Good
I-90 WB over Sunset Creek	2024	139,482	Good
N Queen Anne Dr over Ravine	1935	125,000	Fair
I-5 over Terrain	1966	122,487	Fair
SW Spokane St over Duwamish River W Waterwy	1983	108,179	Fair
I-5 over Terrain	1966	106,282	Fair