Birch Street over Birch Street Viaduct
FairPosted for loadPetersburg Census Area, Alaska · Mile Point 0.1 · Structure no. 1453
- Built
- 1960
- 65 years old, rebuilt 1979
- Condition
- Fair
- inspected May 2023
- Type
- Stringer/Multi-beam or Girder
- Wood or Timber
- Length
- 704 ft
- 70 main spans
- Daily traffic
- 200
- 2018 count
- Owner
- County
- County Highway Agency
About this bridge
Birch Street over Birch Street Viaduct is a wood or timber stringer/multi-beam or girder carrying Birch Street over Birch Street Viaduct in Petersburg Census Area, Alaska. It was built in 1960 and reconstructed in 1979, so it is 65 years old, older than the Alaska average of 35.9 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 200 vehicles a day, roughly 1% of them trucks, projected to reach 240 by 2035. The structure is 704 ft (214.7 m) long and 14 ft wide. If it were closed, the detour would be 123.7 mi (199 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 | 7 Good | Some minor problems. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| 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 Birch Street over Birch Street Viaduct built?
It was built in 1960, making it 65 years old in 2025. It was reconstructed in 1979.
What condition is Birch Street over Birch Street Viaduct 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 May 2023.
How much traffic does Birch Street over Birch Street Viaduct carry?
About 200 vehicles per day (2018 count), of which roughly 1% are trucks.
How long is Birch Street over Birch Street Viaduct?
The structure is 704 ft (214.7 m) long with a longest span of 13 ft (4 m) and a deck 14 ft wide.
Who owns Birch Street over Birch Street Viaduct?
It is owned by the County Highway Agency.