US Bridges

US 2 over Red Rock West Overflow

Good

Blaine County, Montana · 2M W Chinook · Structure no. 000000202005066

Built
2020
5 years old
Condition
Good
inspected September 2024
Type
Slab
Prestressed Concrete
Length
55 ft
2 main spans
Daily traffic
2,732
2023 count
Owner
State
State Highway Agency

About this bridge

US 2 over Red Rock West Overflow is a prestressed concrete slab carrying US 2 over Red Rock West Overflow in Blaine County, Montana. It was built in 2020, so it is 5 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,732 vehicles a day, roughly 6% of them trucks, projected to reach 2,869 by 2043. The structure is 55 ft (16.7 m) long and 80 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesUS 2
CrossesRed Rock West Overflow
Location2M W Chinook
RouteU.S. Route 2
StateMontana
Coordinates48.59636, -109.27624
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating39 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans2
Design loadHL 93
Structure length55 ft (16.7 m)
Longest span26 ft (7.9 m)
Deck width80 ft (24.4 m)
Roadway width73 ft (22.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,732 (2023)
Projected traffic2,869 by 2043
Trucks6%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemYes

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—
NavigationNo navigation control on waterway

Frequently asked questions

When was US 2 over Red Rock West Overflow built?

It was built in 2020, making it 5 years old in 2025.

What condition is US 2 over Red Rock West Overflow 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 September 2024.

How much traffic does US 2 over Red Rock West Overflow carry?

About 2,732 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is US 2 over Red Rock West Overflow?

The structure is 55 ft (16.7 m) long with a longest span of 26 ft (7.9 m) and a deck 80 ft wide.

Who owns US 2 over Red Rock West Overflow?

It is owned by the State Highway Agency.