US-31 NB over Pere Marquette River
FairMason County, Michigan · 3.6 MI SE of Ludington · Structure no. 000000000006645
- Built
- 1989
- 36 years old
- Condition
- Fair
- inspected May 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 400 ft
- 3 main spans
- Daily traffic
- 2,498
- 2007 count
- Owner
- State
- State Highway Agency
About this bridge
US-31 NB over Pere Marquette River is a steel continuous stringer/multi-beam or girder carrying US-31 NB over Pere Marquette River in Mason County, Michigan. It was built in 1989, so it is 36 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 2,498 vehicles a day, roughly 15% of them trucks, projected to reach 3,385 by 2018. The structure is 400 ft (121.9 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. |
| 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 US-31 NB over Pere Marquette River built?
It was built in 1989, making it 36 years old in 2025.
What condition is US-31 NB over Pere Marquette 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 May 2024.
How much traffic does US-31 NB over Pere Marquette River carry?
About 2,498 vehicles per day (2007 count), of which roughly 15% are trucks.
How long is US-31 NB over Pere Marquette River?
The structure is 400 ft (121.9 m) long with a longest span of 152 ft (46.3 m) and a deck 48 ft wide.
Who owns US-31 NB over Pere Marquette River?
It is owned by the State Highway Agency.