M-50 over River Raisin
Monroe County, Michigan · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- M-50 over River Raisin in Monroe County, Michigan, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1937 and reconstructed in 2000, making it 88 years old at the 2025 inventory.
- It carries about 9,360 vehicles a day (traffic count year 2007).
- Its listed owner is the state highway agency.
- It is one of 166 of the 299 inventoried bridges in Monroe County rated fair (55.5%); 40 (13.4%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated October 2023, on a 24-month routine inspection cycle.
- A fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (41.95627, -83.65848)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Prestressed concrete single box beam |
| Length | about 201 ft |
| Location | In Dundee Monroe St |
| NBI structure number | 000000000007070 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | October 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in Monroe County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-75 over Conrail Raisin R Front | 1955 | 67,800 | Poor |
| I-75 over NS & Cn Railroad | 1956 | 65,200 | Good |
| I-75 over Norfolk Southern RR | 1955 | 65,200 | Fair |
| I-75 over Sandy Creek Rd | 1955 | 65,200 | Fair |
| I-75 over Paper Co Water Mains | 1955 | 63,962 | Fair |
| I-75 over Norfolk Southern RR | 1955 | 63,962 | Fair |
All bridges nearby: Monroe County, MI bridge conditions · every bridge in Monroe County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.