US Bridges

NM-104 over LA Manga Creek

Poor

San Miguel County, New Mexico · 8.5 MI E of JCT NM-129 · Structure no. 000000000005253

Built
1952
73 years old
Condition
Poor
inspected November 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
170 ft
8 main spans
Daily traffic
243
2023 count
Owner
State
State Highway Agency

About this bridge

NM-104 over LA Manga Creek is a wood or timber stringer/multi-beam or girder carrying NM-104 over LA Manga Creek in San Miguel County, New Mexico. It was built in 1952, so it is 73 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 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.

It carries about 243 vehicles a day, roughly 11% of them trucks, projected to reach 330 by 2043. The structure is 170 ft (51.8 m) long and 37 ft wide. If it were closed, the detour would be 13 mi (21 km).

CarriesNM-104
CrossesLA Manga Creek
Location8.5 MI E of JCT NM-129
RouteState Highway 104
Coordinates35.35447, -104.15068
Functional classRural Major 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, 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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating39.2 US tons
Inventory rating28.5 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans8
Design loadH 15
Structure length170 ft (51.8 m)
Longest span21 ft (6.4 m)
Deck width37 ft (11.4 m)
Roadway width36 ft (10.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic243 (2023)
Projected traffic330 by 2043
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed13 mi (21 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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$680,000 (2020 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was NM-104 over LA Manga Creek built?

It was built in 1952, making it 73 years old in 2025.

What condition is NM-104 over LA Manga Creek 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 2024.

How much traffic does NM-104 over LA Manga Creek carry?

About 243 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is NM-104 over LA Manga Creek?

The structure is 170 ft (51.8 m) long with a longest span of 21 ft (6.4 m) and a deck 37 ft wide.

Who owns NM-104 over LA Manga Creek?

It is owned by the State Highway Agency.