US 93 over Bitterroot River
Ravalli County, Montana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 93 over Bitterroot River in Ravalli County, Montana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1949 and reconstructed in 1973, making it 76 years old at the 2025 inventory.
- It carries about 6,979 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 77 of the 150 inventoried bridges in Ravalli County rated fair (51.3%); 12 (8.0%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: deck 6 to 5, substructure 6 to 5.
- Its most recent inspection on record is dated April 2024, on a 24-month routine inspection cycle.
- It is coded scour critical (NBI item 113 = 3): scour critical: foundations unstable for the assessed or calculated scour.
- 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 → (46.19869, -114.16836)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 5 | Fair condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 5 | Fair condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 301 ft |
| Location | 3M S Hamilton |
| NBI structure number | P00007043+06661 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 3: scour critical: foundations unstable for the assessed or calculated scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in Ravalli County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 93 over Mill Creek | 2011 | 15,852 | Good |
| US 93 over Corvallis Canal | 1980 | 14,714 | Good |
| US 93 over Bitterroot River | 2005 | 14,573 | Fair |
| US 93 over Blodgett Creek | 2008 | 14,573 | Fair |
| US 93 over S Fork Bear Creek | 2011 | 13,924 | Fair |
| US 93 over N Fork Bear Creek | 2011 | 13,924 | Good |
All bridges nearby: Ravalli County, MT bridge conditions · every bridge in Ravalli County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.