Old 30 Knappa over Big Creek
GoodClatsop County, Oregon · 005 MI NW HWY 30 · Structure no. 07C04 031400065
- Built
- 1972
- 53 years old
- Condition
- Good
- inspected March 2023
- Type
- Box Beam or Girders - Multiple
- Prestressed Concrete
- Length
- 106 ft
- 1 main span
- Daily traffic
- 450
- 2020 count
- Owner
- County
- County Highway Agency
About this bridge
Old 30 Knappa over Big Creek is a prestressed concrete box beam or girders - multiple carrying Old 30 Knappa over Big Creek in Clatsop County, Oregon. It was built in 1972, so it is 53 years old, older 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 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 450 vehicles a day, roughly 10% of them trucks, projected to reach 495 by 2025. The structure is 106 ft (32.3 m) long and 24 ft wide. If it were closed, the detour would be 0.6 mi (1 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 | 7 Good | Some minor problems. |
| 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 Old 30 Knappa over Big Creek built?
It was built in 1972, making it 53 years old in 2025.
What condition is Old 30 Knappa over Big Creek 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 March 2023.
How much traffic does Old 30 Knappa over Big Creek carry?
About 450 vehicles per day (2020 count), of which roughly 10% are trucks.
How long is Old 30 Knappa over Big Creek?
The structure is 106 ft (32.3 m) long with a longest span of 105 ft (32 m) and a deck 24 ft wide.
Who owns Old 30 Knappa over Big Creek?
It is owned by the County Highway Agency.