Thornton Lakes Roa over Thornton Creek
FairSkagit County, Washington · Turn Left from Route 20 a · Structure no. 9470003P0000000
- Built
- 1952
- 73 years old, rebuilt 1979
- Condition
- Fair
- inspected September 2024
- Type
- Stringer/Multi-beam or Girder
- Wood or Timber
- Length
- 51 ft
- 1 main span
- Daily traffic
- 50
- 2019 count
- Owner
- Federal
- National Park Service
About this bridge
Thornton Lakes Roa over Thornton Creek is a wood or timber stringer/multi-beam or girder carrying Thornton Lakes Roa over Thornton Creek in Skagit County, Washington. It was built in 1952 and reconstructed in 1979, so it is 73 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.
It carries about 50 vehicles a day, projected to reach 100 by 2039. The structure is 51 ft (15.5 m) long and 13 ft wide. If it were closed, the detour would be 123.7 mi (199 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Thornton Lakes Roa over Thornton Creek built?
It was built in 1952, making it 73 years old in 2025. It was reconstructed in 1979.
What condition is Thornton Lakes Roa over Thornton Creek 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 September 2024.
How much traffic does Thornton Lakes Roa over Thornton Creek carry?
About 50 vehicles per day (2019 count).
How long is Thornton Lakes Roa over Thornton Creek?
The structure is 51 ft (15.5 m) long with a longest span of 47 ft (14.3 m) and a deck 13 ft wide.
Who owns Thornton Lakes Roa over Thornton Creek?
It is owned by the National Park Service.