M-29 over Marine City Drain
FairSt. Clair County, Michigan · In Algonac · Structure no. 000000000009971
- Built
- 1942
- 83 years old, rebuilt 1997
- Condition
- Fair
- inspected March 2023
- Type
- Box Beam or Girders - Single or Spread
- Prestressed Concrete
- Length
- 35 ft
- 1 main span
- Daily traffic
- 3,717
- 2007 count
- Owner
- State
- State Highway Agency
About this bridge
M-29 over Marine City Drain is a prestressed concrete box beam or girders - single or spread carrying M-29 over Marine City Drain in St. Clair County, Michigan. It was built in 1942 and reconstructed in 1997, so it is 83 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 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 3,717 vehicles a day, roughly 5% of them trucks, projected to reach 5,932 by 2018. The structure is 35 ft (10.7 m) long and 57 ft wide. If it were closed, the detour would be 5 mi (8 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 | 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 M-29 over Marine City Drain built?
It was built in 1942, making it 83 years old in 2025. It was reconstructed in 1997.
What condition is M-29 over Marine City Drain 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 March 2023.
How much traffic does M-29 over Marine City Drain carry?
About 3,717 vehicles per day (2007 count), of which roughly 5% are trucks.
How long is M-29 over Marine City Drain?
The structure is 35 ft (10.7 m) long with a longest span of 32 ft (9.8 m) and a deck 57 ft wide.
Who owns M-29 over Marine City Drain?
It is owned by the State Highway Agency.