I 15 Frontage RD over Boulder River 046
FairJefferson County, Montana · 2M W Basin · Structure no. L22099010+07001
- Built
- 1985
- 40 years old
- Condition
- Fair
- inspected April 2024
- Type
- Tee Beam
- Prestressed Concrete
- Length
- 101 ft
- 3 main spans
- Daily traffic
- 100
- 2025 count
- Owner
- State
- State Highway Agency
About this bridge
I 15 Frontage RD over Boulder River 046 is a prestressed concrete tee beam carrying I 15 Frontage RD over Boulder River 046 in Jefferson County, Montana. It was built in 1985, so it is 40 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 101 ft (30.9 m) long and 14 ft wide. If it were closed, the detour would be 9.9 mi (16 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. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 15 Frontage RD over Boulder River 046 built?
It was built in 1985, making it 40 years old in 2025.
What condition is I 15 Frontage RD over Boulder River 046 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 2024.
How much traffic does I 15 Frontage RD over Boulder River 046 carry?
About 100 vehicles per day (2025 count), of which roughly 3% are trucks.
How long is I 15 Frontage RD over Boulder River 046?
The structure is 101 ft (30.9 m) long with a longest span of 51 ft (15.6 m) and a deck 14 ft wide.
Who owns I 15 Frontage RD over Boulder River 046?
It is owned by the State Highway Agency.