S 89 over Int North Dillon I 15
FairBeaverhead County, Montana · Dillon · Structure no. P00089003+02321
- Built
- 1973
- 52 years old
- Condition
- Fair
- inspected December 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 295 ft
- 4 main spans
- Daily traffic
- 4,241
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
S 89 over Int North Dillon I 15 is a prestressed concrete stringer/multi-beam or girder carrying S 89 over Int North Dillon I 15 in Beaverhead County, Montana. It was built in 1973, so it is 52 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 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 4,241 vehicles a day, roughly 5% of them trucks, projected to reach 4,453 by 2043. The structure is 295 ft (89.8 m) long and 50 ft wide. If it were closed, the detour would be 8.1 mi (13 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 | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was S 89 over Int North Dillon I 15 built?
It was built in 1973, making it 52 years old in 2025.
What condition is S 89 over Int North Dillon I 15 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 December 2024.
How much traffic does S 89 over Int North Dillon I 15 carry?
About 4,241 vehicles per day (2023 count), of which roughly 5% are trucks.
How long is S 89 over Int North Dillon I 15?
The structure is 295 ft (89.8 m) long with a longest span of 100 ft (30.5 m) and a deck 50 ft wide.
Who owns S 89 over Int North Dillon I 15?
It is owned by the State Highway Agency.