US Bridges

31-Z001 over Unnamed Waterway

PoorPosted for load

McKinley County, New Mexico · NM-602 at MP 22.9 · Structure no. 000000000008628

Built
1987
38 years old
Condition
Poor
inspected March 2024
Type
Truss - Thru
Aluminum, Wrought Iron, or Cast Iron
Length
89 ft
3 main spans
Daily traffic
337
2023 count
Owner
County
County Highway Agency

About this bridge

31-Z001 over Unnamed Waterway is a aluminum, wrought iron, or cast iron truss - thru carrying 31-Z001 over Unnamed Waterway in McKinley County, New Mexico. It was built in 1987, so it is 38 years old, younger than the New Mexico average of 51.5 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 337 vehicles a day, projected to reach 458 by 2043. The structure is 89 ft (27.2 m) long and 17 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Carries31-Z001
CrossesUnnamed Waterway
LocationNM-602 at MP 22.9
RouteCounty Highway 31001
Coordinates35.4218, -108.7396
Functional classRural Local

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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMarch 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be 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 rating17.9 US tons
Inventory rating12.5 US tons

Structure

Structure typeTruss - Thru
MaterialAluminum, Wrought Iron, or Cast Iron
DeckAluminum
Main spans3
Design loadHS 15
Structure length89 ft (27.2 m)
Longest span56 ft (17.2 m)
Deck width17 ft (5.2 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic337 (2023)
Projected traffic458 by 2043
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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$224,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 31-Z001 over Unnamed Waterway built?

It was built in 1987, making it 38 years old in 2025.

What condition is 31-Z001 over Unnamed Waterway 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 2024.

How much traffic does 31-Z001 over Unnamed Waterway carry?

About 337 vehicles per day (2023 count).

How long is 31-Z001 over Unnamed Waterway?

The structure is 89 ft (27.2 m) long with a longest span of 56 ft (17.2 m) and a deck 17 ft wide.

Who owns 31-Z001 over Unnamed Waterway?

It is owned by the County Highway Agency.