US Bridges

NM-186 over Rio Grande

Fair

Dona Ana County, New Mexico · 1.2 MI E of JCT NM-28 · Structure no. 000000000005747

Built
1957
68 years old
Condition
Fair
inspected February 2024
Type
Stringer/Multi-beam or Girder
Concrete Continuous
Length
482 ft
12 main spans
Daily traffic
977
2023 count
Owner
County
County Highway Agency

About this bridge

NM-186 over Rio Grande is a concrete continuous stringer/multi-beam or girder carrying NM-186 over Rio Grande in Dona Ana County, New Mexico. It was built in 1957, so it is 68 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 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 977 vehicles a day, roughly 11% of them trucks, projected to reach 1,328 by 2043. The structure is 482 ft (146.9 m) long and 27 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesNM-186
CrossesRio Grande
Location1.2 MI E of JCT NM-28
RouteState Highway 186
CountyDona Ana County
StateNew Mexico
Coordinates32.02302, -106.6493
Functional classRural Major Collector

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating82.1 US tons
Inventory rating49.3 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans12
Design loadHS 15
Structure length482 ft (146.9 m)
Longest span40 ft (12.2 m)
Deck width27 ft (8.3 m)
Roadway width22 ft (6.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic977 (2023)
Projected traffic1,328 by 2043
Trucks11%
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

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$835,000
NavigationNo navigation control on waterway

Frequently asked questions

When was NM-186 over Rio Grande built?

It was built in 1957, making it 68 years old in 2025.

What condition is NM-186 over Rio Grande 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 February 2024.

How much traffic does NM-186 over Rio Grande carry?

About 977 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is NM-186 over Rio Grande?

The structure is 482 ft (146.9 m) long with a longest span of 40 ft (12.2 m) and a deck 27 ft wide.

Who owns NM-186 over Rio Grande?

It is owned by the County Highway Agency.