US Bridges

I 15 over RR (tracks Not in Use)

Fair

Silver Bow County, Montana · Butte · Structure no. I00015130+00261

Built
1986
39 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
219 ft
4 main spans
Daily traffic
2,176
2023 count
Owner
State
State Highway Agency

About this bridge

I 15 over RR (tracks Not in Use) is a prestressed concrete stringer/multi-beam or girder carrying I 15 over RR (tracks Not in Use) in Silver Bow County, Montana. It was built in 1986, so it is 39 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 2,176 vehicles a day, roughly 12% of them trucks, projected to reach 2,350 by 2043. The structure is 219 ft (66.8 m) long and 41 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 15
CrossesRR (tracks Not in Use)
LocationButte
RouteInterstate 15
CountySilver Bow County
StateMontana
Coordinates45.98713, -112.47668
Functional classUrban 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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57 US tons
Inventory rating44 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length219 ft (66.8 m)
Longest span72 ft (21.8 m)
Deck width41 ft (12.6 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,176 (2023)
Projected traffic2,350 by 2043
Trucks12%
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 15 over RR (tracks Not in Use) built?

It was built in 1986, making it 39 years old in 2025.

What condition is I 15 over RR (tracks Not in Use) 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 June 2024.

How much traffic does I 15 over RR (tracks Not in Use) carry?

About 2,176 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is I 15 over RR (tracks Not in Use)?

The structure is 219 ft (66.8 m) long with a longest span of 72 ft (21.8 m) and a deck 41 ft wide.

Who owns I 15 over RR (tracks Not in Use)?

It is owned by the State Highway Agency.