US Bridges

US 191 over Drainage

Fair

Wheatland County, Montana · 12M S Harlowton · Structure no. P00045031+06261

Built
1942
83 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
38 ft
2 main spans
Daily traffic
706
2023 count
Owner
State
State Highway Agency

About this bridge

US 191 over Drainage is a wood or timber stringer/multi-beam or girder carrying US 191 over Drainage in Wheatland County, Montana. It was built in 1942, so it is 83 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 5 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 706 vehicles a day, roughly 12% of them trucks, projected to reach 741 by 2043. The structure is 38 ft (11.6 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 191
CrossesDrainage
Location12M S Harlowton
RouteU.S. Route 191
CountyWheatland County
StateMontana
Coordinates46.26731, -109.88815
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no 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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38 US tons
Inventory rating26 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans2
Design loadH 15
Structure length38 ft (11.6 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 traffic706 (2023)
Projected traffic741 by 2043
Trucks12%
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 191 over Drainage built?

It was built in 1942, making it 83 years old in 2025.

What condition is US 191 over Drainage 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 October 2023.

How much traffic does US 191 over Drainage carry?

About 706 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is US 191 over Drainage?

The structure is 38 ft (11.6 m) long with a longest span of 19 ft (5.8 m) and a deck 26 ft wide.

Who owns US 191 over Drainage?

It is owned by the State Highway Agency.