US Bridges

I 15 over Sep Elk Park-E Elk Park

Fair

Jefferson County, Montana · 12.4M N Butte · Structure no. I00015143+09102

Built
1985
40 years old
Condition
Fair
inspected January 2025
Type
Slab
Concrete Continuous
Length
81 ft
3 main spans
Daily traffic
1,576
2023 count
Owner
State
State Highway Agency

About this bridge

I 15 over Sep Elk Park-E Elk Park is a concrete continuous slab carrying I 15 over Sep Elk Park-E Elk Park 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 1,576 vehicles a day, roughly 16% of them trucks, projected to reach 1,701 by 2043. The structure is 81 ft (24.7 m) long and 40 ft wide.

Location

Open in Google Maps
CarriesI 15
CrossesSep Elk Park-E Elk Park
Location12.4M N Butte
RouteInterstate 15
CountyJefferson County
StateMontana
Coordinates46.16387, -112.37817
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating42 US tons
Inventory rating33 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length81 ft (24.7 m)
Longest span30 ft (9.1 m)
Deck width40 ft (12.3 m)
Roadway width37 ft (11.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,576 (2023)
Projected traffic1,701 by 2043
Trucks16%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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 15 over Sep Elk Park-E Elk Park built?

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

What condition is I 15 over Sep Elk Park-E Elk Park 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 January 2025.

How much traffic does I 15 over Sep Elk Park-E Elk Park carry?

About 1,576 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is I 15 over Sep Elk Park-E Elk Park?

The structure is 81 ft (24.7 m) long with a longest span of 30 ft (9.1 m) and a deck 40 ft wide.

Who owns I 15 over Sep Elk Park-E Elk Park?

It is owned by the State Highway Agency.