1-lane Road over West Fork Rock Creek
Carbon County, Montana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 1-lane Road over West Fork Rock Creek in Carbon County, Montana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1956, making it 69 years old at the 2025 inventory.
- It carries about 50 vehicles a day.
- It is one of 46 of the 81 inventoried bridges in Carbon County rated fair (56.8%); 4 (4.9%) 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 → (45.17222, -109.45963)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Timber stringer or multi-beam girder |
| Length | about 37 ft |
| Location | 11 Miles W. of Red Lodge |
| NBI structure number | 010802000000184 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in Carbon County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 310 over Sand Creek | 1987 | 4,907 | Good |
| US 310 over Rock Creek | 1934 | 4,561 | Fair |
| US 212 over Rock Creek | 1974 | 3,817 | Fair |
| US 212 over Rock Creek | 2001 | 2,491 | Good |
| US 310 over Bridger Creek | 1971 | 1,932 | Fair |
| US 310 over Clarks Fk Yellowstone | 1971 | 1,932 | Fair |
All bridges nearby: Carbon County, MT bridge conditions · every bridge in Carbon County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.