US Bridges

NM-1 over Unnamed Waterway

Fair

Socorro County, New Mexico · 5.4 M E&n/San Marcial Ext · Structure no. 000000000001646

Built
1931
94 years old
Condition
Fair
inspected November 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
103 ft
4 main spans
Daily traffic
174
2023 count
Owner
State
State Highway Agency

About this bridge

NM-1 over Unnamed Waterway is a wood or timber stringer/multi-beam or girder carrying NM-1 over Unnamed Waterway in Socorro County, New Mexico. It was built in 1931, so it is 94 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.

It carries about 174 vehicles a day, roughly 10% of them trucks, projected to reach 236 by 2043. The structure is 103 ft (31.3 m) long and 20 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesNM-1
CrossesUnnamed Waterway
Location5.4 M E&n/San Marcial Ext
RouteState Highway 1
Coordinates33.75431, -106.93566
Functional classRural Minor 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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2023
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 geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating32.4 US tons
Inventory rating18 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans4
Design loadH 15
Structure length103 ft (31.3 m)
Longest span25 ft (7.6 m)
Deck width20 ft (6.2 m)
Roadway width19 ft (5.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic174 (2023)
Projected traffic236 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusEligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$902,000
NavigationNot applicable (no waterway)

Frequently asked questions

When was NM-1 over Unnamed Waterway built?

It was built in 1931, making it 94 years old in 2025.

What condition is NM-1 over Unnamed Waterway 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 November 2023.

How much traffic does NM-1 over Unnamed Waterway carry?

About 174 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is NM-1 over Unnamed Waterway?

The structure is 103 ft (31.3 m) long with a longest span of 25 ft (7.6 m) and a deck 20 ft wide.

Who owns NM-1 over Unnamed Waterway?

It is owned by the State Highway Agency.