I-90 over Yellowstone River
Yellowstone County, Montana · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- I-90 over Yellowstone River in Yellowstone County, Montana, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 2023, making it 2 years old at the 2025 inventory.
- It carries about 14,744 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 186 of the 290 inventoried bridges in Yellowstone County rated fair (64.1%); 7 (2.4%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- It was rated good in the 2024 inventory and is now fair (superstructure 8 to 6).
- Its most recent inspection on record is dated August 2024, on a 24-month routine inspection cycle.
- 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 → (45.79269, -108.47138)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 8 | 8 | Very good condition |
| Superstructure | 8 | 6 | Satisfactory condition |
| Substructure | 8 | 8 | Very good condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 975 ft |
| Location | Billings |
| NBI structure number | 000000202301765 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Montana department of transportation.
Busiest bridges in Yellowstone County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I90 over MT Power RR Spur | 2023 | 29,488 | Good |
| I 90 over City County Drain Ditch | 1966 | 27,985 | Fair |
| King Ave W over Bbwa Canal | 1994 | 26,602 | Fair |
| Mullowney Ln over RR | 2007 | 23,980 | Good |
| Mullowney Ln over RR | 2007 | 23,980 | Fair |
| US 87 over Int Lockwood I 90 | 1966 | 23,199 | Fair |
All bridges nearby: Yellowstone County, MT bridge conditions · every bridge in Yellowstone County · Montana bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.