US Bridges

S 200 over Blackfoot River

Fair

Missoula County, Montana · 1M W Bonner · Structure no. P00024000+05841

Built
2009
16 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
347 ft
3 main spans
Daily traffic
8,302
2023 count
Owner
State
State Highway Agency

About this bridge

S 200 over Blackfoot River is a prestressed concrete stringer/multi-beam or girder carrying S 200 over Blackfoot River in Missoula County, Montana. It was built in 2009, so it is 16 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.

It carries about 8,302 vehicles a day, roughly 3% of them trucks, projected to reach 8,717 by 2043. The structure is 347 ft (105.9 m) long and 46 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesS 200
CrossesBlackfoot River
Location1M W Bonner
RouteState Highway 200
CountyMissoula County
StateMontana
Coordinates46.87296, -113.88372
Functional classUrban Other Principal 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.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
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 rating75.9 US tons
Inventory rating48 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length347 ft (105.9 m)
Longest span127 ft (38.7 m)
Deck width46 ft (14.1 m)
Roadway width31 ft (9.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,302 (2023)
Projected traffic8,717 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 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 Blackfoot River built?

It was built in 2009, making it 16 years old in 2025.

What condition is S 200 over Blackfoot 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 June 2024.

How much traffic does S 200 over Blackfoot River carry?

About 8,302 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is S 200 over Blackfoot River?

The structure is 347 ft (105.9 m) long with a longest span of 127 ft (38.7 m) and a deck 46 ft wide.

Who owns S 200 over Blackfoot River?

It is owned by the State Highway Agency.