US Bridges

US 12 over Dry Wash

FairPosted for load

Rosebud County, Montana · 3M W Ingomar · Structure no. P00014227+03151

Built
1947
78 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
58 ft
3 main spans
Daily traffic
222
2023 count
Owner
State
State Highway Agency

About this bridge

US 12 over Dry Wash is a wood or timber stringer/multi-beam or girder carrying US 12 over Dry Wash in Rosebud County, Montana. It was built in 1947, so it is 78 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. Its operating status is: posted for load restriction.

It carries about 222 vehicles a day, roughly 14% of them trucks, projected to reach 233 by 2043. The structure is 58 ft (17.7 m) long and 26 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesUS 12
CrossesDry Wash
Location3M W Ingomar
RouteU.S. Route 12
CountyRosebud County
StateMontana
Coordinates46.58388, -107.42854
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
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
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating22 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans3
Design loadHS 15
Structure length58 ft (17.7 m)
Longest span19 ft (5.8 m)
Deck width26 ft (7.9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic222 (2023)
Projected traffic233 by 2043
Trucks14%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 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 12 over Dry Wash built?

It was built in 1947, making it 78 years old in 2025.

What condition is US 12 over Dry Wash 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 2024.

How much traffic does US 12 over Dry Wash carry?

About 222 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is US 12 over Dry Wash?

The structure is 58 ft (17.7 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns US 12 over Dry Wash?

It is owned by the State Highway Agency.