US Bridges

IRR BIA RTE 30 over Box Elder Creek

Good

Chouteau County, Montana · 8.4 KM NW of Rocky Boys · Structure no. 00000000000C921

Built
2012
13 years old
Condition
Good
inspected October 2024
Type
Culvert
Concrete
Length
26 ft
2 main spans
Daily traffic
200
2024 count
Owner
Federal
Bureau of Indian Affairs

About this bridge

IRR BIA RTE 30 over Box Elder Creek is a concrete culvert carrying IRR BIA RTE 30 over Box Elder Creek in Chouteau County, Montana. It was built in 2012, so it is 13 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 200 vehicles a day, roughly 10% of them trucks, projected to reach 240 by 2044. The structure is 26 ft (8 m) long and 42 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

CarriesIRR BIA RTE 30
CrossesBox Elder Creek
Location8.4 KM NW of Rocky Boys
RouteFederal Lands Road 30
StateMontana
Coordinates48.30175, -109.88592
Functional classRural Major Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating71.7 US tons
Inventory rating55.1 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHS 20
Structure length26 ft (8 m)
Longest span12 ft (3.7 m)
Deck width42 ft (12.8 m)
Roadway width32 ft (9.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic200 (2024)
Projected traffic240 by 2044
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerBureau of Indian Affairs
Maintained byBureau of Indian Affairs
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 IRR BIA RTE 30 over Box Elder Creek built?

It was built in 2012, making it 13 years old in 2025.

What condition is IRR BIA RTE 30 over Box Elder Creek 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 October 2024.

How much traffic does IRR BIA RTE 30 over Box Elder Creek carry?

About 200 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is IRR BIA RTE 30 over Box Elder Creek?

The structure is 26 ft (8 m) long with a longest span of 12 ft (3.7 m) and a deck 42 ft wide.

Who owns IRR BIA RTE 30 over Box Elder Creek?

It is owned by the Bureau of Indian Affairs.