Oso Loop RD over N.F. Stillaguamish River
GoodSnohomish County, Washington · 0.3 S JCT SR 530 · Structure no. 085766000000000
- Built
- 1990
- 35 years old
- Condition
- Good
- inspected June 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 580 ft
- 5 main spans
- Daily traffic
- 357
- 2023 count
- Owner
- County
- County Highway Agency
About this bridge
Oso Loop RD over N.F. Stillaguamish River is a prestressed concrete continuous stringer/multi-beam or girder carrying Oso Loop RD over N.F. Stillaguamish River in Snohomish County, Washington. It was built in 1990, so it is 35 years old, younger 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 357 vehicles a day, roughly 18% of them trucks, projected to reach 1,000 by 2042. The structure is 580 ft (176.8 m) long and 31 ft wide. If it were closed, the detour would be 3.7 mi (6 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. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Oso Loop RD over N.F. Stillaguamish River built?
It was built in 1990, making it 35 years old in 2025.
What condition is Oso Loop RD over N.F. Stillaguamish River 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 2024.
How much traffic does Oso Loop RD over N.F. Stillaguamish River carry?
About 357 vehicles per day (2023 count), of which roughly 18% are trucks.
How long is Oso Loop RD over N.F. Stillaguamish River?
The structure is 580 ft (176.8 m) long with a longest span of 140 ft (42.7 m) and a deck 31 ft wide.
Who owns Oso Loop RD over N.F. Stillaguamish River?
It is owned by the County Highway Agency.