7TH Street over Black River
St. Clair County, Michigan · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 7TH Street over Black River in St. Clair County, Michigan, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1933 and reconstructed in 2007, making it 92 years old at the 2025 inventory.
- It carries about 9,076 vehicles a day (traffic count year 2012).
- Its listed owner is a city or municipal highway agency.
- It is one of 165 of the 326 inventoried bridges in St. Clair County rated fair (50.6%); 31 (9.5%) are rated poor.
- 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 → (42.97654, -82.42737)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 6 | Satisfactory condition |
| Substructure | 7 | Good condition |
Bridge details
| Structure | Steel movable bascule |
| Length | about 272 ft |
| Location | In Port Huron |
| NBI structure number | 000000000010256 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in St. Clair County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-94 over Stocks Creek Drain | 2011 | 50,660 | Good |
| I-94 & I-69 over M-25 Pine Grove Ave | 1993 | 43,238 | Good |
| M-25 over Black River Spillway | 2000 | 40,250 | Fair |
| I-94 over Stocks Creek | 1964 | 29,650 | Fair |
| M-25 over Howe Drain | 1981 | 28,550 | Fair |
| I-94 & I-69 WB over Black River & Scott Ave | 2011 | 26,010 | Fair |
All bridges nearby: St. Clair County, MI bridge conditions · every bridge in St. Clair County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.