S 89 over Blacktail Creek
FairBeaverhead County, Montana · South Dillon · Structure no. P00089000+03311
- Built
- 1983
- 42 years old
- Condition
- Fair
- inspected February 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 98 ft
- 1 main span
- Daily traffic
- 1,804
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S 89 over Blacktail Creek is a prestressed concrete stringer/multi-beam or girder carrying S 89 over Blacktail Creek in Beaverhead County, Montana. It was built in 1983, so it is 42 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 1,804 vehicles a day, roughly 2% of them trucks, projected to reach 1,939 by 2043. The structure is 98 ft (29.9 m) long and 51 ft wide. If it were closed, the detour would be 5 mi (8 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 | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| 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 S 89 over Blacktail Creek built?
It was built in 1983, making it 42 years old in 2025.
What condition is S 89 over Blacktail 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 February 2024.
How much traffic does S 89 over Blacktail Creek carry?
About 1,804 vehicles per day (2023 count), of which roughly 2% are trucks.
How long is S 89 over Blacktail Creek?
The structure is 98 ft (29.9 m) long with a longest span of 95 ft (29 m) and a deck 51 ft wide.
Who owns S 89 over Blacktail Creek?
It is owned by the State Highway Agency.