I 90 over Drainage
Mineral County, Montana · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- I 90 over Drainage in Mineral County, Montana, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 7 (good condition) on the 0-9 scale.
- It was built in 1986, making it 39 years old at the 2025 inventory.
- It carries about 8,111 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 37 of the 153 inventoried bridges in Mineral County rated good (24.2%); 17 (11.1%) are rated poor.
- 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 → (47.29858, -115.10481)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 7 | Good condition |
Bridge details
| Structure | Steel culvert |
| Length | about 21 ft |
| Location | St. Regis |
| NBI structure number | I00090033+01001 |
| Condition class | Good |
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 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 |
| I 90 over Int Lozeau County Road | 1967 | 7,649 | Good |
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.