US Bridges

31-0012 over Rio Nutria

FairPosted for load

McKinley County, New Mexico · 7.60 MI SE of Mcgaffey · Structure no. 000000000004301

Built
1920
105 years old, rebuilt 1973
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
21 ft
1 main span
Daily traffic
337
2023 count
Owner
County
County Highway Agency

About this bridge

31-0012 over Rio Nutria is a steel stringer/multi-beam or girder carrying 31-0012 over Rio Nutria in McKinley County, New Mexico. It was built in 1920 and reconstructed in 1973, so it is 105 years old, older 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 6 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 21 ft (6.3 m) long and 14 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
Carries31-0012
CrossesRio Nutria
Location7.60 MI SE of Mcgaffey
RouteCounty Highway 31012
CountyMcKinley County
StateNew Mexico
Coordinates35.31406, -108.44117
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating26.8 US tons
Inventory rating19.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckOpen grating
Main spans1
Design loadHS 20
Structure length21 ft (6.3 m)
Longest span19 ft (5.8 m)
Deck width14 ft (4.3 m)
Roadway width13 ft (4.1 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$16,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was 31-0012 over Rio Nutria built?

It was built in 1920, making it 105 years old in 2025. It was reconstructed in 1973.

What condition is 31-0012 over Rio Nutria 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 May 2024.

How much traffic does 31-0012 over Rio Nutria carry?

About 337 vehicles per day (2023 count).

How long is 31-0012 over Rio Nutria?

The structure is 21 ft (6.3 m) long with a longest span of 19 ft (5.8 m) and a deck 14 ft wide.

Who owns 31-0012 over Rio Nutria?

It is owned by the County Highway Agency.