I 90 over Sep L Street
FairGallatin County, Montana · Bozeman · Structure no. I00090308+00001
- Built
- 1968
- 57 years old
- Condition
- Fair
- inspected May 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 143 ft
- 3 main spans
- Daily traffic
- 10,616
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 90 over Sep L Street is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Sep L Street in Gallatin County, Montana. It was built in 1968, so it is 57 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 10,616 vehicles a day, roughly 12% of them trucks, projected to reach 11,465 by 2043. The structure is 143 ft (43.6 m) long and 41 ft wide.
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 | 6 Satisfactory | Structural elements show some minor deterioration. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 90 over Sep L Street built?
It was built in 1968, making it 57 years old in 2025.
What condition is I 90 over Sep L Street 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 May 2024.
How much traffic does I 90 over Sep L Street carry?
About 10,616 vehicles per day (2023 count), of which roughly 12% are trucks.
How long is I 90 over Sep L Street?
The structure is 143 ft (43.6 m) long with a longest span of 61 ft (18.7 m) and a deck 41 ft wide.
Who owns I 90 over Sep L Street?
It is owned by the State Highway Agency.