US Bridges

I 90 over Sep Butler Creek Road

Fair

Missoula County, Montana · 3.7M W Missoula · Structure no. I00090098+04272

Built
1966
59 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
138 ft
3 main spans
Daily traffic
10,499
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over Sep Butler Creek Road is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Sep Butler Creek Road in Missoula County, Montana. It was built in 1966, so it is 59 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 10,499 vehicles a day, roughly 11% of them trucks, projected to reach 11,024 by 2043. The structure is 138 ft (42.1 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 Butler Creek Road
Location3.7M W Missoula
RouteInterstate 90
CountyMissoula County
StateMontana
Coordinates46.93631, -114.09402
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than 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 rating46 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3 (+2 approach)
Design loadHS 20
Structure length138 ft (42.1 m)
Longest span52 ft (15.8 m)
Deck width40 ft (12.2 m)
Roadway width37 ft (11.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,499 (2023)
Projected traffic11,024 by 2043
Trucks11%
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 Butler Creek Road built?

It was built in 1966, making it 59 years old in 2025.

What condition is I 90 over Sep Butler Creek 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 December 2023.

How much traffic does I 90 over Sep Butler Creek Road carry?

About 10,499 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is I 90 over Sep Butler Creek Road?

The structure is 138 ft (42.1 m) long with a longest span of 52 ft (15.8 m) and a deck 40 ft wide.

Who owns I 90 over Sep Butler Creek Road?

It is owned by the State Highway Agency.