Structure 8615C0000000 · King County, WA

I-405 over Pedestrian Trail

Carries I-405 over Pedestrian Trail, 5.2 N Jct SR 520.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructuresets the rating7/9 · Good
Substructuresets the rating7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT243 FT OVERALL50 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 7/9Substructure 7/9

243 ft end to end, longest span 86 ft: about 3 semi-trucks nose to tail. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built1970rebuilt 1994
Length243.1 ft74.1 m
Daily traffic85,426counted 2023
Last inspectedJuly 2023every 24 months

Location

StateWashington
CountyKing
Location5.2 N Jct SR 520
CarriesI-405
CrossesPedestrian Trail
Coordinates47.70568, -122.18019

Physical Characteristics

MaterialPrestressed Concrete Continuous
DesignStringer/Multi-beam
Total Length243.1 ft (74.1 m)
Max Span86.0 ft (26.2 m)
Deck Width81.0 ft (24.7 m)
Deck Area1830.3 sq m
Main Spans3
Year Built1970 (reconstructed 1994)

Traffic

Avg Daily Traffic85,426 (2023)
Truck Traffic6%
Lanes On Bridge6

Inspection & Ownership

Last InspectionJuly 2023
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour CriticalNot applicable
Structure Number0008615C0000000

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges