Second ST S-Us 89 over Yellowstone River
FairPark County, Montana · Gardiner-Second ST S · Structure no. P00011000+01651
- Built
- 1930
- 95 years old, rebuilt 1975
- Condition
- Fair
- inspected July 2023
- Type
- Truss - Deck
- Steel Continuous
- Length
- 409 ft
- 3 main spans
- Daily traffic
- 4,964
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
Second ST S-Us 89 over Yellowstone River is a steel continuous truss - deck carrying Second ST S-Us 89 over Yellowstone River in Park County, Montana. It was built in 1930 and reconstructed in 1975, so it is 95 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 4,964 vehicles a day, roughly 1% of them trucks, projected to reach 5,262 by 2043. The structure is 409 ft (124.6 m) long and 50 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| 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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Second ST S-Us 89 over Yellowstone River built?
It was built in 1930, making it 95 years old in 2025. It was reconstructed in 1975.
What condition is Second ST S-Us 89 over Yellowstone 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 2023.
How much traffic does Second ST S-Us 89 over Yellowstone River carry?
About 4,964 vehicles per day (2023 count), of which roughly 1% are trucks.
How long is Second ST S-Us 89 over Yellowstone River?
The structure is 409 ft (124.6 m) long with a longest span of 192 ft (58.5 m) and a deck 50 ft wide.
Who owns Second ST S-Us 89 over Yellowstone River?
It is owned by the State Highway Agency.