SR 509 over Des Moines Memorial
GoodKing County, Washington · 5.8 N JCT SR 516 · Structure no. 0011070C0000000
- Built
- 1979
- 46 years old
- Condition
- Good
- inspected August 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 300 ft
- 3 main spans
- Daily traffic
- 14,997
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
SR 509 over Des Moines Memorial is a prestressed concrete continuous stringer/multi-beam or girder carrying SR 509 over Des Moines Memorial in King County, Washington. It was built in 1979, so it is 46 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 14,997 vehicles a day, roughly 5% of them trucks, projected to reach 23,190 by 2039. The structure is 300 ft (91.4 m) long and 92 ft wide. If it were closed, the detour would be 8.1 mi (13 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. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was SR 509 over Des Moines Memorial built?
It was built in 1979, making it 46 years old in 2025.
What condition is SR 509 over Des Moines Memorial 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 August 2023.
How much traffic does SR 509 over Des Moines Memorial carry?
About 14,997 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is SR 509 over Des Moines Memorial?
The structure is 300 ft (91.4 m) long with a longest span of 135 ft (41.1 m) and a deck 92 ft wide.
Who owns SR 509 over Des Moines Memorial?
It is owned by the State Highway Agency.