US Bridges

Twin Bridges RD over Antelope Creek 055

FairPosted for load

Sheridan County, Montana · 1M E Antelope · Structure no. L46208001+02001

Built
2008
17 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
53 ft
1 main span
Daily traffic
100
2025 count
Owner
County
County Highway Agency

About this bridge

Twin Bridges RD over Antelope Creek 055 is a steel stringer/multi-beam or girder carrying Twin Bridges RD over Antelope Creek 055 in Sheridan County, Montana. It was built in 2008, so it is 17 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. Its operating status is: posted for load restriction.

It carries about 100 vehicles a day, roughly 3% of them trucks, projected to reach 100 by 2040. The structure is 53 ft (16.1 m) long and 20 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesTwin Bridges RD
CrossesAntelope Creek 055
Location1M E Antelope
RouteCounty Highway 46208
CountySheridan County
StateMontana
Coordinates48.69342, -104.4275
Functional classRural Local

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.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating5 US tons
Inventory rating5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckSteel plate
Main spans1
Design loadUnknown
Structure length53 ft (16.1 m)
Longest span53 ft (16.1 m)
Deck width20 ft (6.1 m)
Roadway width19 ft (5.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2025)
Projected traffic100 by 2040
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$129,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Twin Bridges RD over Antelope Creek 055 built?

It was built in 2008, making it 17 years old in 2025.

What condition is Twin Bridges RD over Antelope Creek 055 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 Twin Bridges RD over Antelope Creek 055 carry?

About 100 vehicles per day (2025 count), of which roughly 3% are trucks.

How long is Twin Bridges RD over Antelope Creek 055?

The structure is 53 ft (16.1 m) long with a longest span of 53 ft (16.1 m) and a deck 20 ft wide.

Who owns Twin Bridges RD over Antelope Creek 055?

It is owned by the County Highway Agency.