IRR over Tongue River
FairRosebud County, Montana · Ashland · Structure no. S00447052+05081
- Built
- 1970
- 55 years old
- Condition
- Fair
- inspected July 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 202 ft
- 3 main spans
- Daily traffic
- 877
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
IRR over Tongue River is a prestressed concrete stringer/multi-beam or girder carrying IRR over Tongue River in Rosebud 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 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 877 vehicles a day, roughly 2% of them trucks, projected to reach 921 by 2043. The structure is 202 ft (61.5 m) long and 42 ft wide. If it were closed, the detour would be 36 mi (58 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Channel and channel protection | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was IRR over Tongue River built?
It was built in 1970, making it 55 years old in 2025.
What condition is IRR over Tongue 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 July 2024.
How much traffic does IRR over Tongue River carry?
About 877 vehicles per day (2023 count), of which roughly 2% are trucks.
How long is IRR over Tongue River?
The structure is 202 ft (61.5 m) long with a longest span of 68 ft (20.7 m) and a deck 42 ft wide.
Who owns IRR over Tongue River?
It is owned by the State Highway Agency.