IRR - S 313 over Overflow Ditch
FairBig Horn County, Montana · 7M SW Hardin · Structure no. S00313008+00411
- Built
- 1988
- 37 years old
- Condition
- Fair
- inspected August 2024
- Type
- Culvert
- Steel
- Length
- 26 ft
- 2 main spans
- Daily traffic
- 899
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
IRR - S 313 over Overflow Ditch is a steel culvert carrying IRR - S 313 over Overflow Ditch in Big Horn County, Montana. It was built in 1988, so it is 37 years old, younger 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 899 vehicles a day, roughly 17% of them trucks, projected to reach 944 by 2043. The structure is 26 ft (7.9 m) long. If it were closed, the detour would be 80.2 mi (129 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 |
|---|---|---|
| Channel and channel protection | 7 Good | Some minor problems. |
| Culvert | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was IRR - S 313 over Overflow Ditch built?
It was built in 1988, making it 37 years old in 2025.
What condition is IRR - S 313 over Overflow Ditch 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 2024.
How much traffic does IRR - S 313 over Overflow Ditch carry?
About 899 vehicles per day (2023 count), of which roughly 17% are trucks.
How long is IRR - S 313 over Overflow Ditch?
The structure is 26 ft (7.9 m) long with a longest span of 13 ft (4 m).
Who owns IRR - S 313 over Overflow Ditch?
It is owned by the State Highway Agency.