I 90 over Clark Fork River
PoorMineral County, Montana · 9.3M W Alberton · Structure no. I00090066+02792
- Built
- 1965
- 60 years old
- Condition
- Poor
- inspected May 2023
- Type
- Girder and Floorbeam System
- Steel Continuous
- Length
- 807 ft
- 3 main spans
- Daily traffic
- 4,088
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 90 over Clark Fork River is a steel continuous girder and floorbeam system carrying I 90 over Clark Fork River in Mineral County, Montana. It was built in 1965, so it is 60 years old, older than the Montana average of 47 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
It carries about 4,088 vehicles a day, roughly 23% of them trucks, projected to reach 4,292 by 2043. The structure is 807 ft (245.9 m) long and 32 ft wide. If it were closed, the detour would be 1.2 mi (2 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 90 over Clark Fork River built?
It was built in 1965, making it 60 years old in 2025.
What condition is I 90 over Clark Fork River in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in May 2023.
How much traffic does I 90 over Clark Fork River carry?
About 4,088 vehicles per day (2023 count), of which roughly 23% are trucks.
How long is I 90 over Clark Fork River?
The structure is 807 ft (245.9 m) long with a longest span of 210 ft (64 m) and a deck 32 ft wide.
Who owns I 90 over Clark Fork River?
It is owned by the State Highway Agency.