Main ST N over Thirty Mile Creek
FairPosted for loadBlaine County, Montana · Harlem · Structure no. S00241001+02531
- Built
- 1957
- 68 years old
- Condition
- Fair
- inspected October 2023
- Type
- Stringer/Multi-beam or Girder
- Wood or Timber
- Length
- 89 ft
- 4 main spans
- Daily traffic
- 546
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
Main ST N over Thirty Mile Creek is a wood or timber stringer/multi-beam or girder carrying Main ST N over Thirty Mile Creek in Blaine County, Montana. It was built in 1957, so it is 68 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. Its operating status is: posted for load restriction.
It carries about 546 vehicles a day, roughly 1% of them trucks, projected to reach 573 by 2043. The structure is 89 ft (27.1 m) long and 26 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 | 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 Main ST N over Thirty Mile Creek built?
It was built in 1957, making it 68 years old in 2025.
What condition is Main ST N over Thirty Mile 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 October 2023.
How much traffic does Main ST N over Thirty Mile Creek carry?
About 546 vehicles per day (2023 count), of which roughly 1% are trucks.
How long is Main ST N over Thirty Mile Creek?
The structure is 89 ft (27.1 m) long with a longest span of 25 ft (7.6 m) and a deck 26 ft wide.
Who owns Main ST N over Thirty Mile Creek?
It is owned by the State Highway Agency.