Old US 91 over Prewett Creek 070
FairCascade County, Montana · 10M S Cascade · Structure no. L07604007+03001
- Built
- 1931
- 94 years old
- Condition
- Fair
- inspected December 2024
- Type
- Tee Beam
- Concrete
- Length
- 80 ft
- 3 main spans
- Daily traffic
- 316
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
Old US 91 over Prewett Creek 070 is a concrete tee beam carrying Old US 91 over Prewett Creek 070 in Cascade County, Montana. It was built in 1931, so it is 94 years old, older than the Montana average of 47 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
It carries about 316 vehicles a day, roughly 2% of them trucks, projected to reach 332 by 2043. The structure is 80 ft (24.4 m) long and 25 ft wide. If it were closed, the detour would be 8.7 mi (14 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Old US 91 over Prewett Creek 070 built?
It was built in 1931, making it 94 years old in 2025.
What condition is Old US 91 over Prewett Creek 070 in?
The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in December 2024.
How much traffic does Old US 91 over Prewett Creek 070 carry?
About 316 vehicles per day (2023 count), of which roughly 2% are trucks.
How long is Old US 91 over Prewett Creek 070?
The structure is 80 ft (24.4 m) long with a longest span of 35 ft (10.7 m) and a deck 25 ft wide.
Who owns Old US 91 over Prewett Creek 070?
It is owned by the State Highway Agency.