I 90 over Lower Deer Creek
FairSweet Grass County, Montana · 0.6M W Greycliff · Structure no. I00090377+02361
- Built
- 1980
- 45 years old
- Condition
- Fair
- inspected September 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 72 ft
- 1 main span
- Daily traffic
- 6,153
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I 90 over Lower Deer Creek is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Lower Deer Creek in Sweet Grass County, Montana. It was built in 1980, so it is 45 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 6,153 vehicles a day, roughly 17% of them trucks, projected to reach 6,614 by 2043. The structure is 72 ft (21.8 m) long and 44 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 | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was I 90 over Lower Deer Creek built?
It was built in 1980, making it 45 years old in 2025.
What condition is I 90 over Lower Deer 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 September 2023.
How much traffic does I 90 over Lower Deer Creek carry?
About 6,153 vehicles per day (2023 count), of which roughly 17% are trucks.
How long is I 90 over Lower Deer Creek?
The structure is 72 ft (21.8 m) long with a longest span of 66 ft (20.1 m) and a deck 44 ft wide.
Who owns I 90 over Lower Deer Creek?
It is owned by the State Highway Agency.