US Bridges

US 191 NB over Niger Canyon

Fair

Greenlee County, Arizona · 3.2 MI N JCT SR 75 · Structure no. 00267

Built
1942
83 years old
Condition
Fair
inspected August 2023
Type
Slab
Concrete Continuous
Length
110 ft
4 main spans
Daily traffic
5,190
2022 count
Owner
State
State Highway Agency

About this bridge

US 191 NB over Niger Canyon is a concrete continuous slab carrying US 191 NB over Niger Canyon in Greenlee County, Arizona. It was built in 1942, so it is 83 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 5 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 5,190 vehicles a day, roughly 7% of them trucks, projected to reach 5,200 by 2042. The structure is 110 ft (33.5 m) long and 29 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS 191 NB
CrossesNiger Canyon
Location3.2 MI N JCT SR 75
RouteU.S. Route 191
CountyGreenlee County
StateArizona
Coordinates32.98291, -109.25974
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
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 geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48 US tons
Inventory rating28 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadH 15
Structure length110 ft (33.5 m)
Longest span27 ft (8.2 m)
Deck width29 ft (8.8 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,190 (2022)
Projected traffic5,200 by 2042
Trucks7%
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 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 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 191 NB over Niger Canyon built?

It was built in 1942, making it 83 years old in 2025.

What condition is US 191 NB over Niger 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 August 2023.

How much traffic does US 191 NB over Niger Canyon carry?

About 5,190 vehicles per day (2022 count), of which roughly 7% are trucks.

How long is US 191 NB over Niger Canyon?

The structure is 110 ft (33.5 m) long with a longest span of 27 ft (8.2 m) and a deck 29 ft wide.

Who owns US 191 NB over Niger Canyon?

It is owned by the State Highway Agency.