I 90 over Clark Fork River
PoorGranite County, Montana · 5M W Drummond · Structure no. I00090148+04361
- Built
- 1970
- 55 years old
- Condition
- Poor
- inspected October 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 255 ft
- 4 main spans
- Daily traffic
- 13,081
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 90 over Clark Fork River is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Clark Fork River in Granite County, Montana. It was built in 1970, so it is 55 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 13,081 vehicles a day, roughly 18% of them trucks, projected to reach 13,997 by 2043. The structure is 255 ft (77.6 m) long and 78 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 | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 90 over Clark Fork River built?
It was built in 1970, making it 55 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 October 2023.
How much traffic does I 90 over Clark Fork River carry?
About 13,081 vehicles per day (2023 count), of which roughly 18% are trucks.
How long is I 90 over Clark Fork River?
The structure is 255 ft (77.6 m) long with a longest span of 87 ft (26.5 m) and a deck 78 ft wide.
Who owns I 90 over Clark Fork River?
It is owned by the State Highway Agency.