SR 20 over Thornton Creek
GoodWhatcom County, Washington · 0.6 E Skagit CO · Structure no. 000000QS0000000
- Built
- 1980
- 45 years old
- Condition
- Good
- inspected June 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 100 ft
- 1 main span
- Daily traffic
- 1,930
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
SR 20 over Thornton Creek is a prestressed concrete stringer/multi-beam or girder carrying SR 20 over Thornton Creek in Whatcom County, Washington. It was built in 1980, so it is 45 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 1,930 vehicles a day, roughly 7% of them trucks, projected to reach 2,778 by 2039. The structure is 100 ft (30.5 m) long and 39 ft wide. If it were closed, the detour would be 98.8 mi (159 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 | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was SR 20 over Thornton Creek built?
It was built in 1980, making it 45 years old in 2025.
What condition is SR 20 over Thornton Creek 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 SR 20 over Thornton Creek carry?
About 1,930 vehicles per day (2023 count), of which roughly 7% are trucks.
How long is SR 20 over Thornton Creek?
The structure is 100 ft (30.5 m) long with a longest span of 97 ft (29.7 m) and a deck 39 ft wide.
Who owns SR 20 over Thornton Creek?
It is owned by the State Highway Agency.