Mountain Loop Hwy. over S.F. Stillaguamish River
FairPosted for loadSnohomish County, Washington · 12.1 E JCT SR 92 · Structure no. 081946000000000
- Built
- 1954
- 71 years old
- Condition
- Fair
- inspected June 2024
- Type
- Truss - Thru
- Steel
- Length
- 211 ft
- 1 main span
- Daily traffic
- 1,756
- 2019 count
- Owner
- County
- County Highway Agency
About this bridge
Mountain Loop Hwy. over S.F. Stillaguamish River is a steel truss - thru carrying Mountain Loop Hwy. over S.F. Stillaguamish River in Snohomish County, Washington. It was built in 1954, so it is 71 years old, older than the Washington average of 49.8 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.
It carries about 1,756 vehicles a day, roughly 3% of them trucks, projected to reach 4,000 by 2042. The structure is 211 ft (64.3 m) long and 29 ft wide. If it were closed, the detour would be 93.8 mi (151 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Mountain Loop Hwy. over S.F. Stillaguamish River built?
It was built in 1954, making it 71 years old in 2025.
What condition is Mountain Loop Hwy. over S.F. Stillaguamish River in?
The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in June 2024.
How much traffic does Mountain Loop Hwy. over S.F. Stillaguamish River carry?
About 1,756 vehicles per day (2019 count), of which roughly 3% are trucks.
How long is Mountain Loop Hwy. over S.F. Stillaguamish River?
The structure is 211 ft (64.3 m) long with a longest span of 163 ft (49.7 m) and a deck 29 ft wide.
Who owns Mountain Loop Hwy. over S.F. Stillaguamish River?
It is owned by the County Highway Agency.