SR 520 over Wls Pkwy & Sammamish R
FairKing County, Washington · 4.9 E JCT I-405 · Structure no. 0010201A0000000
- Built
- 1976
- 49 years old, rebuilt 2010
- Condition
- Fair
- inspected August 2024
- Type
- Box Beam or Girders - Multiple
- Concrete Continuous
- Length
- 387 ft
- 4 main spans
- Daily traffic
- 42,985
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
SR 520 over Wls Pkwy & Sammamish R is a concrete continuous box beam or girders - multiple carrying SR 520 over Wls Pkwy & Sammamish R in King County, Washington. It was built in 1976 and reconstructed in 2010, so it is 49 years old, younger 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 42,985 vehicles a day, roughly 3% of them trucks, projected to reach 70,150 by 2039. The structure is 387 ft (118 m) long and 59 ft wide. If it were closed, the detour would be 1.9 mi (3 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 | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was SR 520 over Wls Pkwy & Sammamish R built?
It was built in 1976, making it 49 years old in 2025. It was reconstructed in 2010.
What condition is SR 520 over Wls Pkwy & Sammamish R 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 August 2024.
How much traffic does SR 520 over Wls Pkwy & Sammamish R carry?
About 42,985 vehicles per day (2023 count), of which roughly 3% are trucks.
How long is SR 520 over Wls Pkwy & Sammamish R?
The structure is 387 ft (118 m) long with a longest span of 127 ft (38.7 m) and a deck 59 ft wide.
Who owns SR 520 over Wls Pkwy & Sammamish R?
It is owned by the State Highway Agency.