State Route 181 over Mill CR
FairPosted for loadKing County, Washington · 0.1 MI N of S 277th ST · Structure no. 0004718A0000000
- Built
- 1954
- 71 years old
- Condition
- Fair
- inspected April 2024
- Type
- Slab
- Concrete Continuous
- Length
- 60 ft
- 3 main spans
- Daily traffic
- 20,000
- 2020 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
State Route 181 over Mill CR is a concrete continuous slab carrying State Route 181 over Mill CR in King 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 20,000 vehicles a day, roughly 4% of them trucks, projected to reach 35,000 by 2040. The structure is 60 ft (18.3 m) long and 40 ft wide. If it were closed, the detour would be 6.2 mi (10 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 | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was State Route 181 over Mill CR built?
It was built in 1954, making it 71 years old in 2025.
What condition is State Route 181 over Mill CR 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 April 2024.
How much traffic does State Route 181 over Mill CR carry?
About 20,000 vehicles per day (2020 count), of which roughly 4% are trucks.
How long is State Route 181 over Mill CR?
The structure is 60 ft (18.3 m) long with a longest span of 22 ft (6.7 m) and a deck 40 ft wide.
Who owns State Route 181 over Mill CR?
It is owned by the City or Municipal Highway Agency.