US Bridges

Stp 7151;N Main ST over Portneuf River

Fair

Bannock County, Idaho · In Pocatello;main Arthur · Structure no. 000000000021305

Built
1957
68 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Concrete
Length
90 ft
3 main spans
Daily traffic
9,600
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Stp 7151;N Main ST over Portneuf River is a concrete stringer/multi-beam or girder carrying Stp 7151;N Main ST over Portneuf River in Bannock County, Idaho. It was built in 1957, 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 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 9,600 vehicles a day, roughly 4% of them trucks, projected to reach 14,400 by 2042. The structure is 90 ft (27.4 m) long and 87 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesStp 7151;N Main ST
CrossesPortneuf River
LocationIn Pocatello;main Arthur
RouteCity Street 7151
CountyBannock County
StateIdaho
Coordinates42.88564, -112.47708
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating56 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length90 ft (27.4 m)
Longest span29 ft (8.8 m)
Deck width87 ft (26.4 m)
Roadway width66 ft (20.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,600 (2023)
Projected traffic14,400 by 2042
Trucks4%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Stp 7151;N Main ST over Portneuf River built?

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

What condition is Stp 7151;N Main ST over Portneuf 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 2024.

How much traffic does Stp 7151;N Main ST over Portneuf River carry?

About 9,600 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Stp 7151;N Main ST over Portneuf River?

The structure is 90 ft (27.4 m) long with a longest span of 29 ft (8.8 m) and a deck 87 ft wide.

Who owns Stp 7151;N Main ST over Portneuf River?

It is owned by the City or Municipal Highway Agency.