US Bridges

31-MC43 over Rio Puerco

FairPosted for load

McKinley County, New Mexico · 3.1M NW NM566/CARSONS-T.0 · Structure no. 000000000007895

Built
1980
45 years old
Condition
Fair
inspected March 2024
Type
Truss - Thru
Aluminum, Wrought Iron, or Cast Iron
Length
107 ft
1 main span
Daily traffic
337
2023 count
Owner
County
County Highway Agency

About this bridge

31-MC43 over Rio Puerco is a aluminum, wrought iron, or cast iron truss - thru carrying 31-MC43 over Rio Puerco in McKinley County, New Mexico. It was built in 1980, so it is 45 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 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. Its operating status is: posted for load restriction.

It carries about 337 vehicles a day, projected to reach 458 by 2043. The structure is 107 ft (32.6 m) long and 17 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
Carries31-MC43
CrossesRio Puerco
Location3.1M NW NM566/CARSONS-T.0
RouteCounty Highway 31002
CountyMcKinley County
StateNew Mexico
Coordinates35.58272, -108.61061
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour above top of footing
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 alignment6: Equal to present minimum criteria
Operating rating28.5 US tons
Inventory rating16.1 US tons

Structure

Structure typeTruss - Thru
MaterialAluminum, Wrought Iron, or Cast Iron
DeckAluminum
Main spans1
Design loadH 15
Structure length107 ft (32.6 m)
Longest span102 ft (31.1 m)
Deck width17 ft (5.2 m)
Roadway width15 ft (4.6 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 closed9.9 mi (16 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$269,000 (2020 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was 31-MC43 over Rio Puerco built?

It was built in 1980, making it 45 years old in 2025.

What condition is 31-MC43 over Rio Puerco 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 2024.

How much traffic does 31-MC43 over Rio Puerco carry?

About 337 vehicles per day (2023 count).

How long is 31-MC43 over Rio Puerco?

The structure is 107 ft (32.6 m) long with a longest span of 102 ft (31.1 m) and a deck 17 ft wide.

Who owns 31-MC43 over Rio Puerco?

It is owned by the County Highway Agency.