US Bridges

US 287 over Milligan Creek

Fair

Broadwater County, Montana · 6M SW Three Forks · Structure no. P00013089+01061

Built
1968
57 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
102 ft
2 main spans
Daily traffic
1,553
2023 count
Owner
State
State Highway Agency

About this bridge

US 287 over Milligan Creek is a prestressed concrete stringer/multi-beam or girder carrying US 287 over Milligan Creek in Broadwater County, Montana. It was built in 1968, so it is 57 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 1,553 vehicles a day, roughly 10% of them trucks, projected to reach 1,631 by 2043. The structure is 102 ft (31.1 m) long and 39 ft wide. If it were closed, the detour would be 52.2 mi (84 km).

Location

Open in Google Maps
CarriesUS 287
CrossesMilligan Creek
Location6M SW Three Forks
RouteU.S. Route 287
CountyBroadwater County
StateMontana
Coordinates45.85651, -111.65435
Functional classRural Minor Arterial

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.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50 US tons
Inventory rating39 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length102 ft (31.1 m)
Longest span50 ft (15.2 m)
Deck width39 ft (11.9 m)
Roadway width37 ft (11.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,553 (2023)
Projected traffic1,631 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed52.2 mi (84 km)
TollOn a free road
National Highway SystemNo

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 US 287 over Milligan Creek built?

It was built in 1968, making it 57 years old in 2025.

What condition is US 287 over Milligan 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 December 2023.

How much traffic does US 287 over Milligan Creek carry?

About 1,553 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is US 287 over Milligan Creek?

The structure is 102 ft (31.1 m) long with a longest span of 50 ft (15.2 m) and a deck 39 ft wide.

Who owns US 287 over Milligan Creek?

It is owned by the State Highway Agency.