US Bridges

I 90 over Sep Pope Road

Fair

Stillwater County, Montana · 1.9M E Park City · Structure no. I00090428+01551

Built
1967
58 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
125 ft
3 main spans
Daily traffic
7,580
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over Sep Pope Road is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Sep Pope Road in Stillwater County, Montana. It was built in 1967, so it is 58 years old, older 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 7,580 vehicles a day, roughly 16% of them trucks, projected to reach 8,261 by 2043. The structure is 125 ft (38.1 m) long and 40 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 90
CrossesSep Pope Road
Location1.9M E Park City
RouteInterstate 90
CountyStillwater County
StateMontana
Coordinates45.64159, -108.8844
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2023
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 alignment8: Equal to present desirable criteria
Operating rating49.1 US tons
Inventory rating28 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length125 ft (38.1 m)
Longest span42 ft (12.8 m)
Deck width40 ft (12.3 m)
Roadway width37 ft (11.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,580 (2023)
Projected traffic8,261 by 2043
Trucks16%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
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 90 over Sep Pope Road built?

It was built in 1967, making it 58 years old in 2025.

What condition is I 90 over Sep Pope Road 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 September 2023.

How much traffic does I 90 over Sep Pope Road carry?

About 7,580 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is I 90 over Sep Pope Road?

The structure is 125 ft (38.1 m) long with a longest span of 42 ft (12.8 m) and a deck 40 ft wide.

Who owns I 90 over Sep Pope Road?

It is owned by the State Highway Agency.