US Bridges

I 90 over Upper Deer Creek

Fair

Sweet Grass County, Montana · 2.5M W Greycliff · Structure no. I00090375+04862

Built
1980
45 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
172 ft
2 main spans
Daily traffic
6,153
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over Upper Deer Creek is a prestressed concrete stringer/multi-beam or girder carrying I 90 over Upper Deer Creek in Sweet Grass County, Montana. It was built in 1980, so it is 45 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 6,153 vehicles a day, roughly 17% of them trucks, projected to reach 6,614 by 2043. The structure is 172 ft (52.4 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI 90
CrossesUpper Deer Creek
Location2.5M W Greycliff
RouteInterstate 90
StateMontana
Coordinates45.7933, -109.83287
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
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 geometry7: Better than present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating93.5 US tons
Inventory rating40.8 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length172 ft (52.4 m)
Longest span86 ft (26.2 m)
Deck width44 ft (13.3 m)
Roadway width41 ft (12.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,153 (2023)
Projected traffic6,614 by 2043
Trucks17%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 90 over Upper Deer Creek built?

It was built in 1980, making it 45 years old in 2025.

What condition is I 90 over Upper Deer Creek 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 Upper Deer Creek carry?

About 6,153 vehicles per day (2023 count), of which roughly 17% are trucks.

How long is I 90 over Upper Deer Creek?

The structure is 172 ft (52.4 m) long with a longest span of 86 ft (26.2 m) and a deck 44 ft wide.

Who owns I 90 over Upper Deer Creek?

It is owned by the State Highway Agency.