US Bridges

IRR US 70 over Wildhorse Canyon

Good

Graham County, Arizona · 30.8 MI E JCT SR 77 · Structure no. 04288

Built
1956
69 years old
Condition
Good
inspected May 2023
Type
Culvert
Concrete Continuous
Length
24 ft
2 main spans
Daily traffic
2,904
2021 count
Owner
State
State Highway Agency

About this bridge

IRR US 70 over Wildhorse Canyon is a concrete continuous culvert carrying IRR US 70 over Wildhorse Canyon in Graham County, Arizona. It was built in 1956, so it is 69 years old, older than the Arizona average of 47.8 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 2,904 vehicles a day, roughly 12% of them trucks, projected to reach 2,914 by 2041. The structure is 24 ft (7.3 m) long. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesIRR US 70
CrossesWildhorse Canyon
Location30.8 MI E JCT SR 77
RouteU.S. Route 70
CountyGraham County
StateArizona
Coordinates33.23133, -110.23924
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating72 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,904 (2021)
Projected traffic2,914 by 2041
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1,000
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR US 70 over Wildhorse Canyon built?

It was built in 1956, making it 69 years old in 2025.

What condition is IRR US 70 over Wildhorse Canyon 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 May 2023.

How much traffic does IRR US 70 over Wildhorse Canyon carry?

About 2,904 vehicles per day (2021 count), of which roughly 12% are trucks.

How long is IRR US 70 over Wildhorse Canyon?

The structure is 24 ft (7.3 m) long with a longest span of 10 ft (3 m).

Who owns IRR US 70 over Wildhorse Canyon?

It is owned by the State Highway Agency.