US 191 FH 42 over Gallatin River
FairGallatin County, Montana · 4M NE Big Sky · Structure no. P00050049+08111
- Built
- 1952
- 73 years old
- Condition
- Fair
- inspected January 2025
- Type
- Tee Beam
- Concrete Continuous
- Length
- 160 ft
- 3 main spans
- Daily traffic
- 8,952
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 191 FH 42 over Gallatin River is a concrete continuous tee beam carrying US 191 FH 42 over Gallatin River in Gallatin County, Montana. It was built in 1952, so it is 73 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 5 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 8,952 vehicles a day, roughly 5% of them trucks, projected to reach 10,519 by 2043. The structure is 160 ft (48.8 m) long and 33 ft wide. If it were closed, the detour would be 110 mi (177 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 191 FH 42 over Gallatin River built?
It was built in 1952, making it 73 years old in 2025.
What condition is US 191 FH 42 over Gallatin River 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 January 2025.
How much traffic does US 191 FH 42 over Gallatin River carry?
About 8,952 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is US 191 FH 42 over Gallatin River?
The structure is 160 ft (48.8 m) long with a longest span of 60 ft (18.3 m) and a deck 33 ft wide.
Who owns US 191 FH 42 over Gallatin River?
It is owned by the State Highway Agency.