US Bridges

I 90 over Int Laurel-P 4-RR

Fair

Yellowstone County, Montana · Laurel · Structure no. I00090434+00901

Built
1964
61 years old, rebuilt 2007
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
366 ft
2 main spans
Daily traffic
9,599
2023 count
Owner
State
State Highway Agency

About this bridge

I 90 over Int Laurel-P 4-RR is a steel stringer/multi-beam or girder carrying I 90 over Int Laurel-P 4-RR in Yellowstone County, Montana. It was built in 1964 and reconstructed in 2007, so it is 61 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 9,599 vehicles a day, roughly 13% of them trucks, projected to reach 10,463 by 2043. The structure is 366 ft (111.5 m) long and 39 ft wide.

Location

Open in Google Maps
CarriesI 90
CrossesInt Laurel-P 4-RR
LocationLaurel
RouteInterstate 90
CountyYellowstone County
StateMontana
Coordinates45.66247, -108.76967
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30 US tons
Inventory rating23 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2 (+3 approach)
Design loadHS 20
Structure length366 ft (111.5 m)
Longest span112 ft (34.1 m)
Deck width39 ft (12 m)
Roadway width37 ft (11.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,599 (2023)
Projected traffic10,463 by 2043
Trucks13%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$761,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 90 over Int Laurel-P 4-RR built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 2007.

What condition is I 90 over Int Laurel-P 4-RR 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 2023.

How much traffic does I 90 over Int Laurel-P 4-RR carry?

About 9,599 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is I 90 over Int Laurel-P 4-RR?

The structure is 366 ft (111.5 m) long with a longest span of 112 ft (34.1 m) and a deck 39 ft wide.

Who owns I 90 over Int Laurel-P 4-RR?

It is owned by the State Highway Agency.