S Frontage Rd W over Clark Fork 053
Mineral County, Montana · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- S Frontage Rd W over Clark Fork 053 in Mineral County, Montana, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1916 and reconstructed in 1999, making it 109 years old at the 2025 inventory.
- It carries about 174 vehicles a day (traffic count year 2023).
- Its listed owner is the county highway agency.
- It is one of 17 of the 153 inventoried bridges in Mineral County rated poor (11.1%); 17 (11.1%) are rated poor.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (47.01401, -114.50756)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 4 | Poor condition |
| Substructure | 5 | Fair condition |
Bridge details
| Structure | Steel through truss |
| Length | about 371 ft |
| Location | 2M W Alberton |
| NBI structure number | L31089001+04001 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in Mineral County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I 90 over Drainage | 1986 | 8,111 | Good |
| I 90 over Sep Local Road | 1973 | 7,824 | Fair |
| I 90 over Sep Local Road | 1973 | 7,824 | Fair |
| I 90 over Int Taft | 1973 | 7,824 | Fair |
| I 90 over Sep Randolph Creek Road | 1973 | 7,824 | Fair |
| I 90 over St. Regis River | 1973 | 7,824 | Fair |
All bridges nearby: Mineral County, MT bridge conditions · every bridge in Mineral County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.