US Bridges

IRR SR 73; over Coal Mine Canyon

Fair

Navajo County, Arizona · 7.0 MI S JCT SR 260 · Structure no. 00982

Built
1967
58 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
194 ft
3 main spans
Daily traffic
7,999
2024 count
Owner
State
State Highway Agency

About this bridge

IRR SR 73; over Coal Mine Canyon is a steel continuous stringer/multi-beam or girder carrying IRR SR 73; over Coal Mine Canyon in Navajo County, Arizona. It was built in 1967, so it is 58 years old, older than the Arizona average of 47.8 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 7,999 vehicles a day, roughly 4% of them trucks, projected to reach 8,009 by 2042. The structure is 194 ft (59.1 m) long and 37 ft wide. If it were closed, the detour would be 42.9 mi (69 km).

Location

Open in Google Maps
CarriesIRR SR 73;
CrossesCoal Mine Canyon
Location7.0 MI S JCT SR 260
RouteState Highway 73
CountyNavajo County
StateArizona
Coordinates33.9934, -109.9099
Functional classRural 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating43 US tons
Inventory rating25 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length194 ft (59.1 m)
Longest span90 ft (27.4 m)
Deck width37 ft (11.2 m)
Roadway width34 ft (10.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,999 (2024)
Projected traffic8,009 by 2042
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed42.9 mi (69 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 proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$1,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR SR 73; over Coal Mine Canyon built?

It was built in 1967, making it 58 years old in 2025.

What condition is IRR SR 73; over Coal Mine Canyon 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 September 2024.

How much traffic does IRR SR 73; over Coal Mine Canyon carry?

About 7,999 vehicles per day (2024 count), of which roughly 4% are trucks.

How long is IRR SR 73; over Coal Mine Canyon?

The structure is 194 ft (59.1 m) long with a longest span of 90 ft (27.4 m) and a deck 37 ft wide.

Who owns IRR SR 73; over Coal Mine Canyon?

It is owned by the State Highway Agency.