US Bridges

Arkansas Road over Portneuf Marsh Val.Cnl

FairPosted for load

Bannock County, Idaho · 1.9 S. 0.7 E. Arimo · Structure no. 000000000022030

Built
1957
68 years old, rebuilt 2019
Condition
Fair
inspected April 2023
Type
Slab
Concrete
Length
28 ft
1 main span
Daily traffic
50
2023 count
Owner
County
County Highway Agency

About this bridge

Arkansas Road over Portneuf Marsh Val.Cnl is a concrete slab carrying Arkansas Road over Portneuf Marsh Val.Cnl in Bannock County, Idaho. It was built in 1957 and reconstructed in 2019, so it is 68 years old, older than the Idaho average of 45.3 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. Its operating status is: posted for load restriction.

It carries about 50 vehicles a day, roughly 10% of them trucks, projected to reach 75 by 2039. The structure is 28 ft (8.5 m) long and 24 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesArkansas Road
CrossesPortneuf Marsh Val.Cnl
Location1.9 S. 0.7 E. Arimo
RouteCounty Highway 0
CountyBannock County
StateIdaho
Coordinates42.53381, -112.15833
Functional classRural 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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating48.2 US tons
Inventory rating37.1 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length28 ft (8.5 m)
Longest span25 ft (7.6 m)
Deck width24 ft (7.4 m)
Roadway width22 ft (6.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2023)
Projected traffic75 by 2039
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.2 mi (18 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Arkansas Road over Portneuf Marsh Val.Cnl built?

It was built in 1957, making it 68 years old in 2025. It was reconstructed in 2019.

What condition is Arkansas Road over Portneuf Marsh Val.Cnl 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 April 2023.

How much traffic does Arkansas Road over Portneuf Marsh Val.Cnl carry?

About 50 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is Arkansas Road over Portneuf Marsh Val.Cnl?

The structure is 28 ft (8.5 m) long with a longest span of 25 ft (7.6 m) and a deck 24 ft wide.

Who owns Arkansas Road over Portneuf Marsh Val.Cnl?

It is owned by the County Highway Agency.