US Bridges

IRR BIA RTE N4 over Wepo Wash

Poor

Navajo County, Arizona · 1 MI East of Pinon Az · Structure no. 00000000000N540

Built
1990
35 years old
Condition
Poor
inspected March 2023
Type
Culvert
Concrete Continuous
Length
27 ft
4 main spans
Daily traffic
4,078
2023 count
Owner
Federal
Bureau of Indian Affairs

About this bridge

IRR BIA RTE N4 over Wepo Wash is a concrete continuous culvert carrying IRR BIA RTE N4 over Wepo Wash in Navajo County, Arizona. It was built in 1990, so it is 35 years old, younger than the Arizona average of 47.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 4,078 vehicles a day, roughly 10% of them trucks, projected to reach 4,721 by 2043. The structure is 27 ft (8.1 m) long and 93 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesIRR BIA RTE N4
CrossesWepo Wash
Location1 MI East of Pinon Az
RouteFederal Lands Road 0N4
CountyNavajo County
StateArizona
Coordinates36.09136, -110.21014
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60.1 US tons
Inventory rating35.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans4
Design loadHS 20
Structure length27 ft (8.1 m)
Longest span6 ft (1.8 m)
Deck width93 ft (28.2 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,078 (2023)
Projected traffic4,721 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 N4 over Wepo Wash built?

It was built in 1990, making it 35 years old in 2025.

What condition is IRR BIA RTE N4 over Wepo Wash in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in March 2023.

How much traffic does IRR BIA RTE N4 over Wepo Wash carry?

About 4,078 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is IRR BIA RTE N4 over Wepo Wash?

The structure is 27 ft (8.1 m) long with a longest span of 6 ft (1.8 m) and a deck 93 ft wide.

Who owns IRR BIA RTE N4 over Wepo Wash?

It is owned by the Bureau of Indian Affairs.