US Bridges

IRR BIA RTE N59 over Long Flat Wash

Fair

Navajo County, Arizona · 8 MI NW of Agency Line · Structure no. 00000000000N327

Built
1969
56 years old
Condition
Fair
inspected March 2023
Type
Culvert
Steel
Length
27 ft
2 main spans
Daily traffic
1,620
2023 count
Owner
Federal
Bureau of Indian Affairs

About this bridge

IRR BIA RTE N59 over Long Flat Wash is a steel culvert carrying IRR BIA RTE N59 over Long Flat Wash in Navajo County, Arizona. It was built in 1969, so it is 56 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 1,620 vehicles a day, roughly 10% of them trucks, projected to reach 1,895 by 2043. The structure is 27 ft (8.2 m) long and 63 ft wide. If it were closed, the detour would be 19.9 mi (32 km).

Location

Open in Google Maps
CarriesIRR BIA RTE N59
CrossesLong Flat Wash
Location8 MI NW of Agency Line
RouteFederal Lands Road 0N59
CountyNavajo County
StateArizona
Coordinates36.53419, -110.03514
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating49.1 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length27 ft (8.2 m)
Longest span12 ft (3.7 m)
Deck width63 ft (19.2 m)
Roadway width36 ft (11.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,620 (2023)
Projected traffic1,895 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.9 mi (32 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerBureau of Indian Affairs
Maintained byBureau of Indian Affairs
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR BIA RTE N59 over Long Flat Wash built?

It was built in 1969, making it 56 years old in 2025.

What condition is IRR BIA RTE N59 over Long Flat Wash 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 March 2023.

How much traffic does IRR BIA RTE N59 over Long Flat Wash carry?

About 1,620 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is IRR BIA RTE N59 over Long Flat Wash?

The structure is 27 ft (8.2 m) long with a longest span of 12 ft (3.7 m) and a deck 63 ft wide.

Who owns IRR BIA RTE N59 over Long Flat Wash?

It is owned by the Bureau of Indian Affairs.