US Bridges

I 84 Wbl over Phyllis Canal

Good

Canyon County, Idaho · In Nampa · Structure no. 000000000015601

Built
2012
13 years old
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
69 ft
1 main span
Daily traffic
55,500
2023 count
Owner
State
State Highway Agency

About this bridge

I 84 Wbl over Phyllis Canal is a prestressed concrete stringer/multi-beam or girder carrying I 84 Wbl over Phyllis Canal in Canyon County, Idaho. It was built in 2012, so it is 13 years old, younger than the Idaho average of 45.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 55,500 vehicles a day, roughly 14% of them trucks, projected to reach 83,250 by 2042. The structure is 69 ft (21 m) long and 77 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI 84 Wbl
CrossesPhyllis Canal
LocationIn Nampa
RouteInterstate 84
StateIdaho
Coordinates43.59861, -116.54861
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionFebruary 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations on dry land well above flood water elevations
Structural evaluation8: Equal to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60.4 US tons
Inventory rating46.7 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length69 ft (21 m)
Longest span64 ft (19.5 m)
Deck width77 ft (23.5 m)
Roadway width74 ft (22.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic55,500 (2023)
Projected traffic83,250 by 2042
Trucks14%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 84 Wbl over Phyllis Canal built?

It was built in 2012, making it 13 years old in 2025.

What condition is I 84 Wbl over Phyllis Canal in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in February 2023.

How much traffic does I 84 Wbl over Phyllis Canal carry?

About 55,500 vehicles per day (2023 count), of which roughly 14% are trucks.

How long is I 84 Wbl over Phyllis Canal?

The structure is 69 ft (21 m) long with a longest span of 64 ft (19.5 m) and a deck 77 ft wide.

Who owns I 84 Wbl over Phyllis Canal?

It is owned by the State Highway Agency.