SR 181 over Slough
GoodKing County, Washington · 2.8 N JCT SR 516 · Structure no. 0008509A0000000
- Built
- 1922
- 103 years old, rebuilt 1990
- Condition
- Good
- inspected September 2023
- Type
- Tee Beam
- Concrete
- Length
- 43 ft
- 1 main span
- Daily traffic
- 30,762
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
SR 181 over Slough is a concrete tee beam carrying SR 181 over Slough in King County, Washington. It was built in 1922 and reconstructed in 1990, so it is 103 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 30,762 vehicles a day, roughly 9% of them trucks, projected to reach 44,069 by 2039. The structure is 43 ft (13.1 m) long and 110 ft wide. If it were closed, the detour would be 6.2 mi (10 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 | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was SR 181 over Slough built?
It was built in 1922, making it 103 years old in 2025. It was reconstructed in 1990.
What condition is SR 181 over Slough 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 September 2023.
How much traffic does SR 181 over Slough carry?
About 30,762 vehicles per day (2023 count), of which roughly 9% are trucks.
How long is SR 181 over Slough?
The structure is 43 ft (13.1 m) long with a longest span of 41 ft (12.5 m) and a deck 110 ft wide.
Who owns SR 181 over Slough?
It is owned by the State Highway Agency.