US Bridges

31-0049 over Rio Puerco of the West

PoorPosted for load

McKinley County, New Mexico · 8.3 MI N of NM-566 · Structure no. 000000000010023

Built
1988
37 years old
Condition
Poor
inspected November 2023
Type
Truss - Thru
Aluminum, Wrought Iron, or Cast Iron
Length
135 ft
3 main spans
Daily traffic
179
2023 count
Owner
County
County Highway Agency

About this bridge

31-0049 over Rio Puerco of the West is a aluminum, wrought iron, or cast iron truss - thru carrying 31-0049 over Rio Puerco of the West in McKinley County, New Mexico. It was built in 1988, so it is 37 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 179 vehicles a day, roughly 11% of them trucks, projected to reach 243 by 2043. The structure is 135 ft (41.1 m) long and 16 ft wide. If it were closed, the detour would be 5 mi (8 km).

Carries31-0049
CrossesRio Puerco of the West
Location8.3 MI N of NM-566
RouteCounty Highway 31049
Coordinates35.62467, -108.43628
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionNovember 2023
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
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 rating26.8 US tons
Inventory rating14.3 US tons

Structure

Structure typeTruss - Thru
MaterialAluminum, Wrought Iron, or Cast Iron
DeckAluminum
Main spans3
Design loadUnknown
Structure length135 ft (41.1 m)
Longest span45 ft (13.7 m)
Deck width16 ft (4.8 m)
Roadway width15 ft (4.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic179 (2023)
Projected traffic243 by 2043
Trucks11%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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$340,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was 31-0049 over Rio Puerco of the West built?

It was built in 1988, making it 37 years old in 2025.

What condition is 31-0049 over Rio Puerco of the West 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 November 2023.

How much traffic does 31-0049 over Rio Puerco of the West carry?

About 179 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is 31-0049 over Rio Puerco of the West?

The structure is 135 ft (41.1 m) long with a longest span of 45 ft (13.7 m) and a deck 16 ft wide.

Who owns 31-0049 over Rio Puerco of the West?

It is owned by the County Highway Agency.