US Bridges

Marias Valley RD over Sep I 15 010

Fair

Toole County, Montana · 7M S Shelby · Structure no. L51306000+09001

Built
1976
49 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
296 ft
4 main spans
Daily traffic
511
2023 count
Owner
State
State Highway Agency

About this bridge

Marias Valley RD over Sep I 15 010 is a prestressed concrete stringer/multi-beam or girder carrying Marias Valley RD over Sep I 15 010 in Toole County, Montana. It was built in 1976, so it is 49 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 511 vehicles a day, roughly 3% of them trucks, projected to reach 539 by 2043. The structure is 296 ft (90.1 m) long and 34 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesMarias Valley RD
CrossesSep I 15 010
Location7M S Shelby
RouteState Highway 81007
CountyToole County
StateMontana
Coordinates48.39721, -111.91773
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating50 US tons
Inventory rating21.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length296 ft (90.1 m)
Longest span105 ft (32 m)
Deck width34 ft (10.4 m)
Roadway width31 ft (9.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic511 (2023)
Projected traffic539 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Marias Valley RD over Sep I 15 010 built?

It was built in 1976, making it 49 years old in 2025.

What condition is Marias Valley RD over Sep I 15 010 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 October 2023.

How much traffic does Marias Valley RD over Sep I 15 010 carry?

About 511 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Marias Valley RD over Sep I 15 010?

The structure is 296 ft (90.1 m) long with a longest span of 105 ft (32 m) and a deck 34 ft wide.

Who owns Marias Valley RD over Sep I 15 010?

It is owned by the State Highway Agency.