US Bridges

IRR BIA RTE 60 over Main Drain

PoorPosted for load

La Paz County, Arizona · 1.6 KM West of BIA 1 · Structure no. 00000000000H036

Built
1955
70 years old
Condition
Poor
inspected February 2024
Type
Stringer/Multi-beam or Girder
Concrete
Length
79 ft
4 main spans
Daily traffic
10
2021 count
Owner
Federal
Bureau of Indian Affairs

About this bridge

IRR BIA RTE 60 over Main Drain is a concrete stringer/multi-beam or girder carrying IRR BIA RTE 60 over Main Drain in La Paz County, Arizona. It was built in 1955, so it is 70 years old, older 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. Its operating status is: posted for load restriction.

It carries about 10 vehicles a day, roughly 15% of them trucks, projected to reach 12 by 2036. The structure is 79 ft (24 m) long and 22 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesIRR BIA RTE 60
CrossesMain Drain
Location1.6 KM West of BIA 1
RouteFederal Lands Road 60
StateArizona
Coordinates33.73789, -114.48728
Functional classRural Minor 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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating24.3 US tons
Inventory rating17.9 US tons

Structure

MaterialConcrete
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length79 ft (24 m)
Longest span20 ft (6 m)
Deck width22 ft (6.6 m)
Roadway width21 ft (6.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (2021)
Projected traffic12 by 2036
Trucks15%
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1.2 million (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR BIA RTE 60 over Main Drain built?

It was built in 1955, making it 70 years old in 2025.

What condition is IRR BIA RTE 60 over Main Drain 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 February 2024.

How much traffic does IRR BIA RTE 60 over Main Drain carry?

About 10 vehicles per day (2021 count), of which roughly 15% are trucks.

How long is IRR BIA RTE 60 over Main Drain?

The structure is 79 ft (24 m) long with a longest span of 20 ft (6 m) and a deck 22 ft wide.

Who owns IRR BIA RTE 60 over Main Drain?

It is owned by the Bureau of Indian Affairs.