S 59 over Mill Creek-Stockpass
FairCuster County, Montana · 7M SE Miles City · Structure no. P00023009+05021
- Built
- 1986
- 39 years old
- Condition
- Fair
- inspected April 2023
- Type
- Culvert
- Steel
- Length
- 32 ft
- 2 main spans
- Daily traffic
- 942
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S 59 over Mill Creek-Stockpass is a steel culvert carrying S 59 over Mill Creek-Stockpass in Custer County, Montana. It was built in 1986, so it is 39 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 942 vehicles a day, roughly 12% of them trucks, projected to reach 989 by 2043. The structure is 32 ft (9.8 m) long. If it were closed, the detour would be 85.1 mi (137 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Culvert | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was S 59 over Mill Creek-Stockpass built?
It was built in 1986, making it 39 years old in 2025.
What condition is S 59 over Mill Creek-Stockpass 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 April 2023.
How much traffic does S 59 over Mill Creek-Stockpass carry?
About 942 vehicles per day (2023 count), of which roughly 12% are trucks.
How long is S 59 over Mill Creek-Stockpass?
The structure is 32 ft (9.8 m) long with a longest span of 14 ft (4.4 m).
Who owns S 59 over Mill Creek-Stockpass?
It is owned by the State Highway Agency.