Marshland Dist 504 over Westport Slough
GoodColumbia County, Oregon · 040 MI W Clatskanie · Structure no. 17475 412700002
- Built
- 1995
- 30 years old
- Condition
- Good
- inspected May 2023
- Type
- Slab
- Prestressed Concrete
- Length
- 192 ft
- 3 main spans
- Daily traffic
- 608
- 2020 count
- Owner
- County
- County Highway Agency
About this bridge
Marshland Dist 504 over Westport Slough is a prestressed concrete slab carrying Marshland Dist 504 over Westport Slough in Columbia County, Oregon. It was built in 1995, so it is 30 years old, younger than the Oregon average of 49.9 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 608 vehicles a day, roughly 10% of them trucks, projected to reach 671 by 2025. The structure is 192 ft (58.5 m) long and 24 ft wide. If it were closed, the detour would be 4.3 mi (7 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 | 8 Very Good | No problems noted. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 8 Very Good | No problems noted. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Marshland Dist 504 over Westport Slough built?
It was built in 1995, making it 30 years old in 2025.
What condition is Marshland Dist 504 over Westport 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 May 2023.
How much traffic does Marshland Dist 504 over Westport Slough carry?
About 608 vehicles per day (2020 count), of which roughly 10% are trucks.
How long is Marshland Dist 504 over Westport Slough?
The structure is 192 ft (58.5 m) long with a longest span of 64 ft (19.5 m) and a deck 24 ft wide.
Who owns Marshland Dist 504 over Westport Slough?
It is owned by the County Highway Agency.