Grosvenor Hwy over Swamp Raisin Drain
Lenawee County, Michigan · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Grosvenor Hwy over Swamp Raisin Drain in Lenawee County, Michigan, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 7 (good condition) on the 0-9 scale.
- It was built in 2008, making it 17 years old at the 2025 inventory.
- It carries about 192 vehicles a day (traffic count year 2012).
- Its listed owner is the county highway agency.
- It is one of 94 of the 225 inventoried bridges in Lenawee County rated good (41.8%); 26 (11.6%) are rated poor.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (41.90912, -83.9053)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 7 | Good condition |
Bridge details
| Structure | Concrete culvert |
| Length | about 36 ft |
| Location | 0.2 Mi South of Mitchell |
| NBI structure number | 000000000005686 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in Lenawee County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| M-52 over Beaver Creek | 1919 | 18,099 | Fair |
| M-52 over S Br Raisin River | 1948 | 17,411 | Fair |
| US-223 over Norfolk Southern RR | 1941 | 16,443 | Poor |
| US-223 over Raisin River | 1940 | 13,979 | Fair |
| Bentoak Ave over S Branch Raisin River | 1952 | 13,600 | Fair |
| US-223 over Mdot RR Cor & M-34 | 2006 | 13,595 | Fair |
All bridges nearby: Lenawee County, MI bridge conditions · every bridge in Lenawee County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.