I-405 over N-W Ramp
GoodKing County, Washington · 3.6 N JCT I-90 · Structure no. 0007596A0000000
- Built
- 1965
- 60 years old, rebuilt 2014
- Condition
- Good
- inspected June 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 249 ft
- 3 main spans
- Daily traffic
- 83,247
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I-405 over N-W Ramp is a prestressed concrete continuous stringer/multi-beam or girder carrying I-405 over N-W Ramp in King County, Washington. It was built in 1965 and reconstructed in 2014, so it is 60 years old, older than the Washington average of 49.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 83,247 vehicles a day, roughly 6% of them trucks, projected to reach 123,914 by 2039. The structure is 249 ft (75.9 m) long and 82 ft wide. If it were closed, the detour would be 1.2 mi (2 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I-405 over N-W Ramp built?
It was built in 1965, making it 60 years old in 2025. It was reconstructed in 2014.
What condition is I-405 over N-W Ramp in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in June 2023.
How much traffic does I-405 over N-W Ramp carry?
About 83,247 vehicles per day (2023 count), of which roughly 6% are trucks.
How long is I-405 over N-W Ramp?
The structure is 249 ft (75.9 m) long with a longest span of 94 ft (28.7 m) and a deck 82 ft wide.
Who owns I-405 over N-W Ramp?
It is owned by the State Highway Agency.