US Bridges

I 90 over RR

Fair

Mineral County, Montana · 9.3M W Alberton · Structure no. I00090066+04211

Built
1981
44 years old
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
329 ft
4 main spans
Daily traffic
4,088
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over RR is a prestressed concrete stringer/multi-beam or girder carrying I 90 over RR in Mineral County, Montana. It was built in 1981, so it is 44 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 4,088 vehicles a day, roughly 23% of them trucks, projected to reach 4,292 by 2043. The structure is 329 ft (100.2 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 90
CrossesRR
Location9.3M W Alberton
RouteInterstate 90
CountyMineral County
StateMontana
Coordinates47.01895, -114.65535
Functional classRural Principal Arterial - Interstate

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46 US tons
Inventory rating29 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length329 ft (100.2 m)
Longest span108 ft (32.9 m)
Deck width44 ft (13.5 m)
Roadway width41 ft (12.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,088 (2023)
Projected traffic4,292 by 2043
Trucks23%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 I 90 over RR built?

It was built in 1981, making it 44 years old in 2025.

What condition is I 90 over RR 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 2023.

How much traffic does I 90 over RR carry?

About 4,088 vehicles per day (2023 count), of which roughly 23% are trucks.

How long is I 90 over RR?

The structure is 329 ft (100.2 m) long with a longest span of 108 ft (32.9 m) and a deck 44 ft wide.

Who owns I 90 over RR?

It is owned by the State Highway Agency.