US Bridges

S 7 over Beaver Creek

Fair

Wibaux County, Montana · South Edge of Wibaux · Structure no. P00027079+06091

Built
1949
76 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
153 ft
5 main spans
Daily traffic
1,671
2023 count
Owner
State
State Highway Agency

About this bridge

S 7 over Beaver Creek is a steel continuous stringer/multi-beam or girder carrying S 7 over Beaver Creek in Wibaux County, Montana. It was built in 1949, so it is 76 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 1,671 vehicles a day, roughly 4% of them trucks, projected to reach 1,755 by 2043. The structure is 153 ft (46.5 m) long and 35 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesS 7
CrossesBeaver Creek
LocationSouth Edge of Wibaux
RouteState Highway 7
CountyWibaux County
StateMontana
Coordinates46.98381, -104.18883
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating47 US tons
Inventory rating28 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 15
Structure length153 ft (46.5 m)
Longest span30 ft (9.1 m)
Deck width35 ft (10.6 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,671 (2023)
Projected traffic1,755 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 S 7 over Beaver Creek built?

It was built in 1949, making it 76 years old in 2025.

What condition is S 7 over Beaver 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 August 2023.

How much traffic does S 7 over Beaver Creek carry?

About 1,671 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is S 7 over Beaver Creek?

The structure is 153 ft (46.5 m) long with a longest span of 30 ft (9.1 m) and a deck 35 ft wide.

Who owns S 7 over Beaver Creek?

It is owned by the State Highway Agency.