US Bridges

I 84B Nbl over Snake River;heyburn Br.

Fair

Cassia County, Idaho · At Burley Ncl · Structure no. 000000000013670

Built
1955
70 years old, rebuilt 1978
Condition
Fair
inspected August 2024
Type
Tee Beam
Prestressed Concrete
Length
1,313 ft
32 main spans
Daily traffic
15,000
2023 count
Owner
State
State Highway Agency

About this bridge

I 84B Nbl over Snake River;heyburn Br. is a prestressed concrete tee beam carrying I 84B Nbl over Snake River;heyburn Br. in Cassia County, Idaho. It was built in 1955 and reconstructed in 1978, so it is 70 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.

It carries about 15,000 vehicles a day, roughly 5% of them trucks, projected to reach 22,500 by 2042. The structure is 1,313 ft (400.2 m) long and 37 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 84B Nbl
CrossesSnake River;heyburn Br.
LocationAt Burley Ncl
RouteInterstate 84
CountyCassia County
StateIdaho
Coordinates42.54333, -113.76306
Functional classUrban Minor 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
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 rating40 US tons
Inventory rating24 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans32
Design loadHS 20
Structure length1,313 ft (400.2 m)
Longest span40 ft (12.2 m)
Deck width37 ft (11.3 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,000 (2023)
Projected traffic22,500 by 2042
Trucks5%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$17.3 million (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I 84B Nbl over Snake River;heyburn Br. built?

It was built in 1955, making it 70 years old in 2025. It was reconstructed in 1978.

What condition is I 84B Nbl over Snake River;heyburn Br. 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 August 2024.

How much traffic does I 84B Nbl over Snake River;heyburn Br. carry?

About 15,000 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is I 84B Nbl over Snake River;heyburn Br.?

The structure is 1,313 ft (400.2 m) long with a longest span of 40 ft (12.2 m) and a deck 37 ft wide.

Who owns I 84B Nbl over Snake River;heyburn Br.?

It is owned by the State Highway Agency.