US Bridges

I 84 Wbl over Purple Sage Gs

Fair

Canyon County, Idaho · 3.3 W. Caldwell · Structure no. 000000000015455

Built
1962
63 years old
Condition
Fair
inspected October 2021
Type
Stringer/Multi-beam or Girder
Concrete
Length
108 ft
3 main spans
Daily traffic
15,500
2023 count
Owner
State
State Highway Agency

About this bridge

I 84 Wbl over Purple Sage Gs is a concrete stringer/multi-beam or girder carrying I 84 Wbl over Purple Sage Gs in Canyon County, Idaho. It was built in 1962, so it is 63 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 15,500 vehicles a day, roughly 21% of them trucks, projected to reach 23,250 by 2042. The structure is 108 ft (32.9 m) long and 40 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 84 Wbl
CrossesPurple Sage Gs
Location3.3 W. Caldwell
RouteInterstate 84
CountyCanyon County
StateIdaho
Coordinates43.73537, -116.70872
Functional classRural Principal Arterial - Interstate

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.
Last inspectionOctober 2021
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length108 ft (32.9 m)
Longest span35 ft (10.7 m)
Deck width40 ft (12.2 m)
Roadway width37 ft (11.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic15,500 (2023)
Projected traffic23,250 by 2042
Trucks21%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 84 Wbl over Purple Sage Gs built?

It was built in 1962, making it 63 years old in 2025.

What condition is I 84 Wbl over Purple Sage Gs 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 2021.

How much traffic does I 84 Wbl over Purple Sage Gs carry?

About 15,500 vehicles per day (2023 count), of which roughly 21% are trucks.

How long is I 84 Wbl over Purple Sage Gs?

The structure is 108 ft (32.9 m) long with a longest span of 35 ft (10.7 m) and a deck 40 ft wide.

Who owns I 84 Wbl over Purple Sage Gs?

It is owned by the State Highway Agency.