US-45 over E Br of Ontonagon River
Ontonagon County, Michigan · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US-45 over E Br of Ontonagon River in Ontonagon County, Michigan, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 1958 and reconstructed in 1995, making it 67 years old at the 2025 inventory.
- It carries about 1,540 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 25 of the 66 inventoried bridges in Ontonagon County rated good (37.9%); 10 (15.2%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- It was rated fair in the 2024 inventory and is now good (deck 6 to 7).
- Its most recent inspection on record is dated June 2024, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (46.69952, -89.15989)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous steel girder and floorbeam |
| Length | about 382 ft |
| Location | 2.0 Mi S of M-26 |
| NBI structure number | 000000000008500 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | June 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Michigan department of transportation.
Busiest bridges in Ontonagon County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| M-64 & M-38 over Ontonagon R River Rd RR | 2005 | 3,625 | Fair |
| M-28 over So Br Ontonagon River | 1990 | 2,398 | Good |
| M-28 over M Br Ontonagon River | 1929 | 2,303 | Fair |
| M-28|m-64 over Merryweather Creek | 1932 | 2,120 | Fair |
| M-64 over Cranberry River | 1948 | 2,117 | Fair |
| M-64 over Weigels Creek | 1945 | 2,117 | Fair |
All bridges nearby: Ontonagon County, MI bridge conditions · every bridge in Ontonagon County · Michigan bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.