S 80 over Tributary Flat Creek
FairChouteau County, Montana · 2M NW Square Butte · Structure no. P00080033+04531
- Built
- 1949
- 76 years old, rebuilt 1964
- Condition
- Fair
- inspected August 2023
- Type
- Stringer/Multi-beam or Girder
- Wood or Timber
- Length
- 27 ft
- 1 main span
- Daily traffic
- 235
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S 80 over Tributary Flat Creek is a wood or timber stringer/multi-beam or girder carrying S 80 over Tributary Flat Creek in Chouteau County, Montana. It was built in 1949 and reconstructed in 1964, so it is 76 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 235 vehicles a day, roughly 12% of them trucks, projected to reach 247 by 2043. The structure is 27 ft (8.2 m) long and 30 ft wide. If it were closed, the detour would be 123.7 mi (199 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was S 80 over Tributary Flat Creek built?
It was built in 1949, making it 76 years old in 2025. It was reconstructed in 1964.
What condition is S 80 over Tributary Flat Creek 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 August 2023.
How much traffic does S 80 over Tributary Flat Creek carry?
About 235 vehicles per day (2023 count), of which roughly 12% are trucks.
How long is S 80 over Tributary Flat Creek?
The structure is 27 ft (8.2 m) long with a longest span of 25 ft (7.6 m) and a deck 30 ft wide.
Who owns S 80 over Tributary Flat Creek?
It is owned by the State Highway Agency.