Ninth Avenue over Thunder Bay River
FairAlpena County, Michigan · 0.23 MI E of US23 HWY · Structure no. 000000000000358
- Built
- 1971
- 54 years old, rebuilt 2006
- Condition
- Fair
- inspected July 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 245 ft
- 3 main spans
- Daily traffic
- 5,123
- 2005 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
Ninth Avenue over Thunder Bay River is a prestressed concrete stringer/multi-beam or girder carrying Ninth Avenue over Thunder Bay River in Alpena County, Michigan. It was built in 1971 and reconstructed in 2006, so it is 54 years old, older than the Michigan average of 48.3 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.
It carries about 5,123 vehicles a day, roughly 3% of them trucks, projected to reach 9,250 by 2025. The structure is 245 ft (74.6 m) long and 64 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 | 7 Good | Some minor problems. |
| Superstructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Ninth Avenue over Thunder Bay River built?
It was built in 1971, making it 54 years old in 2025. It was reconstructed in 2006.
What condition is Ninth Avenue over Thunder Bay River 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 July 2023.
How much traffic does Ninth Avenue over Thunder Bay River carry?
About 5,123 vehicles per day (2005 count), of which roughly 3% are trucks.
How long is Ninth Avenue over Thunder Bay River?
The structure is 245 ft (74.6 m) long with a longest span of 82 ft (24.9 m) and a deck 64 ft wide.
Who owns Ninth Avenue over Thunder Bay River?
It is owned by the City or Municipal Highway Agency.