US 87 over Marias River
GoodChouteau County, Montana · Loma · Structure no. P00010051+06521
- Built
- 1988
- 37 years old
- Condition
- Good
- inspected May 2023
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 273 ft
- 3 main spans
- Daily traffic
- 1,417
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 87 over Marias River is a prestressed concrete stringer/multi-beam or girder carrying US 87 over Marias River in Chouteau County, Montana. It was built in 1988, so it is 37 years old, younger than the Montana average of 47 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 1,417 vehicles a day, roughly 12% of them trucks, projected to reach 1,488 by 2043. The structure is 273 ft (83.2 m) long and 42 ft wide. If it were closed, the detour would be 123.7 mi (199 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 8 Very Good | No problems noted. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 87 over Marias River built?
It was built in 1988, making it 37 years old in 2025.
What condition is US 87 over Marias River in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2023.
How much traffic does US 87 over Marias River carry?
About 1,417 vehicles per day (2023 count), of which roughly 12% are trucks.
How long is US 87 over Marias River?
The structure is 273 ft (83.2 m) long with a longest span of 101 ft (30.9 m) and a deck 42 ft wide.
Who owns US 87 over Marias River?
It is owned by the State Highway Agency.