US Bridges

S 9th St-Island DR over Yellowstone River 070

Fair

Park County, Montana · Livingston-S 9th ST · Structure no. L34391000+01001

Built
2011
14 years old
Condition
Fair
inspected February 2025
Type
Tee Beam
Prestressed Concrete
Length
204 ft
2 main spans
Daily traffic
101
2023 count
Owner
County
County Highway Agency

About this bridge

S 9th St-Island DR over Yellowstone River 070 is a prestressed concrete tee beam carrying S 9th St-Island DR over Yellowstone River 070 in Park County, Montana. It was built in 2011, so it is 14 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 101 vehicles a day, roughly 3% of them trucks, projected to reach 108 by 2043. The structure is 204 ft (62.3 m) long and 20 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

Location

Open in Google Maps
CarriesS 9th St-Island DR
CrossesYellowstone River 070
LocationLivingston-S 9th ST
RouteCounty Highway 34391
CountyPark County
StateMontana
Coordinates45.64994, -110.56194
Functional classUrban Local

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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating45.7 US tons
Inventory rating35.1 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans2
Design loadHL 93
Structure length204 ft (62.3 m)
Longest span101 ft (30.7 m)
Deck width20 ft (6.2 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic101 (2023)
Projected traffic108 by 2043
Trucks3%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$341,000
NavigationNo navigation control on waterway

Frequently asked questions

When was S 9th St-Island DR over Yellowstone River 070 built?

It was built in 2011, making it 14 years old in 2025.

What condition is S 9th St-Island DR over Yellowstone River 070 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 February 2025.

How much traffic does S 9th St-Island DR over Yellowstone River 070 carry?

About 101 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is S 9th St-Island DR over Yellowstone River 070?

The structure is 204 ft (62.3 m) long with a longest span of 101 ft (30.7 m) and a deck 20 ft wide.

Who owns S 9th St-Island DR over Yellowstone River 070?

It is owned by the County Highway Agency.