US Bridges

I 15 Frontage RD over Bison Creek 047

Fair

Jefferson County, Montana · 4M W Basin · Structure no. L22099012+08001

Built
1985
40 years old
Condition
Fair
inspected July 2024
Type
Tee Beam
Prestressed Concrete
Length
52 ft
1 main span
Daily traffic
100
2025 count
Owner
State
State Highway Agency

About this bridge

I 15 Frontage RD over Bison Creek 047 is a prestressed concrete tee beam carrying I 15 Frontage RD over Bison Creek 047 in Jefferson County, Montana. It was built in 1985, so it is 40 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 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 52 ft (15.8 m) long and 16 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

CarriesI 15 Frontage RD
CrossesBison Creek 047
Location4M W Basin
RouteState Highway 22099
StateMontana
Coordinates46.26045, -112.32929
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating42 US tons
Inventory rating27 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length52 ft (15.8 m)
Longest span49 ft (14.9 m)
Deck width16 ft (4.8 m)
Roadway width15 ft (4.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 15 Frontage RD over Bison Creek 047 built?

It was built in 1985, making it 40 years old in 2025.

What condition is I 15 Frontage RD over Bison Creek 047 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 July 2024.

How much traffic does I 15 Frontage RD over Bison Creek 047 carry?

About 100 vehicles per day (2025 count), of which roughly 3% are trucks.

How long is I 15 Frontage RD over Bison Creek 047?

The structure is 52 ft (15.8 m) long with a longest span of 49 ft (14.9 m) and a deck 16 ft wide.

Who owns I 15 Frontage RD over Bison Creek 047?

It is owned by the State Highway Agency.