US-31 SB over Old US-31
FairMason County, Michigan · 3.5 MI SE of Ludington · Structure no. 000000000006653
- Built
- 1986
- 39 years old
- Condition
- Fair
- inspected April 2024
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 93 ft
- 1 main span
- Daily traffic
- 4,256
- 2007 count
- Owner
- State
- State Highway Agency
About this bridge
US-31 SB over Old US-31 is a steel stringer/multi-beam or girder carrying US-31 SB over Old US-31 in Mason County, Michigan. It was built in 1986, so it is 39 years old, younger 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 6 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 4,256 vehicles a day, roughly 15% of them trucks, projected to reach 3,385 by 2018. The structure is 93 ft (28.3 m) long and 48 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US-31 SB over Old US-31 built?
It was built in 1986, making it 39 years old in 2025.
What condition is US-31 SB over Old US-31 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 2024.
How much traffic does US-31 SB over Old US-31 carry?
About 4,256 vehicles per day (2007 count), of which roughly 15% are trucks.
How long is US-31 SB over Old US-31?
The structure is 93 ft (28.3 m) long with a longest span of 93 ft (28.3 m) and a deck 48 ft wide.
Who owns US-31 SB over Old US-31?
It is owned by the State Highway Agency.