US Bridges

IRR/US-550 over Arroyo Semilla

Fair

Sandoval County, New Mexico · 40.6 MI NW of JCT I-25 · Structure no. 000000000004000

Built
1938
87 years old, rebuilt 2000
Condition
Fair
inspected January 2025
Type
Culvert
Concrete
Length
43 ft
4 main spans
Daily traffic
5,416
2023 count
Owner
State
State Highway Agency

About this bridge

IRR/US-550 over Arroyo Semilla is a concrete culvert carrying IRR/US-550 over Arroyo Semilla in Sandoval County, New Mexico. It was built in 1938 and reconstructed in 2000, so it is 87 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 5,416 vehicles a day, roughly 17% of them trucks, projected to reach 7,365 by 2043. The structure is 43 ft (13.1 m) long. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesIRR/US-550
CrossesArroyo Semilla
Location40.6 MI NW of JCT I-25
RouteU.S. Route 550
CountySandoval County
StateNew Mexico
Coordinates35.70056, -106.93568
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJanuary 2025
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans4
Design loadHS 20
Structure length43 ft (13.1 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,416 (2023)
Projected traffic7,365 by 2043
Trucks17%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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$177,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR/US-550 over Arroyo Semilla built?

It was built in 1938, making it 87 years old in 2025. It was reconstructed in 2000.

What condition is IRR/US-550 over Arroyo Semilla 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 January 2025.

How much traffic does IRR/US-550 over Arroyo Semilla carry?

About 5,416 vehicles per day (2023 count), of which roughly 17% are trucks.

How long is IRR/US-550 over Arroyo Semilla?

The structure is 43 ft (13.1 m) long with a longest span of 10 ft (3 m).

Who owns IRR/US-550 over Arroyo Semilla?

It is owned by the State Highway Agency.