M-79 over Little Thornapple River
FairEaton County, Michigan · 3.0 MI W of Charlotte · Structure no. 000000000002219
- Built
- 1946
- 79 years old, rebuilt 1990
- Condition
- Fair
- inspected April 2023
- Type
- Box Beam or Girders - Multiple
- Prestressed Concrete
- Length
- 23 ft
- 1 main span
- Daily traffic
- 5,470
- 2007 count
- Owner
- State
- State Highway Agency
About this bridge
M-79 over Little Thornapple River is a prestressed concrete box beam or girders - multiple carrying M-79 over Little Thornapple River in Eaton County, Michigan. It was built in 1946 and reconstructed in 1990, so it is 79 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 5,470 vehicles a day, roughly 3% of them trucks, projected to reach 7,585 by 2018. The structure is 23 ft (7.1 m) long and 47 ft wide. If it were closed, the detour would be 3.1 mi (5 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| 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 M-79 over Little Thornapple River built?
It was built in 1946, making it 79 years old in 2025. It was reconstructed in 1990.
What condition is M-79 over Little Thornapple 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 April 2023.
How much traffic does M-79 over Little Thornapple River carry?
About 5,470 vehicles per day (2007 count), of which roughly 3% are trucks.
How long is M-79 over Little Thornapple River?
The structure is 23 ft (7.1 m) long with a longest span of 22 ft (6.7 m) and a deck 47 ft wide.
Who owns M-79 over Little Thornapple River?
It is owned by the State Highway Agency.