US Bridges

S 200 over Musselshell River

Fair

Garfield County, Montana · Mosby · Structure no. P00057158+03721

Built
1973
52 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
374 ft
4 main spans
Daily traffic
483
2023 count
Owner
State
State Highway Agency

About this bridge

S 200 over Musselshell River is a prestressed concrete stringer/multi-beam or girder carrying S 200 over Musselshell River in Garfield County, Montana. It was built in 1973, so it is 52 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 483 vehicles a day, roughly 15% of them trucks, projected to reach 507 by 2043. The structure is 374 ft (114 m) long and 36 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesS 200
CrossesMusselshell River
LocationMosby
RouteState Highway 200
CountyGarfield County
StateMontana
Coordinates46.99425, -107.88921
Functional classRural Principal Arterial - Other

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating27 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length374 ft (114 m)
Longest span95 ft (29 m)
Deck width36 ft (11.1 m)
Roadway width33 ft (10.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic483 (2023)
Projected traffic507 by 2043
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemYes

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 200 over Musselshell River built?

It was built in 1973, making it 52 years old in 2025.

What condition is S 200 over Musselshell River 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 S 200 over Musselshell River carry?

About 483 vehicles per day (2023 count), of which roughly 15% are trucks.

How long is S 200 over Musselshell River?

The structure is 374 ft (114 m) long with a longest span of 95 ft (29 m) and a deck 36 ft wide.

Who owns S 200 over Musselshell River?

It is owned by the State Highway Agency.