SIERRA HWY
Carrying SIERRA HWY over UNNAMED WASH
2.0MI S/O KERN CO LINE, Los Angeles, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
SIERRA HWY in Los Angeles, California sits above 16% of rated California bridges on inventory load rating (24 t), while its 1921 build year is earlier than 99% of Los Angeles's recorded-year cohort (3,547 bridges).
SIERRA HWY in Los Angeles, California is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1921, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure CA:53C0389
PRE-1950 · CONCRETE · MULTI-SPAN · CULVERT-LED · ARTERIAL-ADT · STANDARD-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- ARTERIAL-ADT Arterial ADT
- STANDARD-LOAD Standard load
- CAT-POOR Poor
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: SIERRA HWY
The SIERRA HWY bridge in Los Angeles, California carries SIERRA HWY over UNNAMED WASH. It was built in 1921, making it 105 years old today. It was last reconstructed in 1931, extending its service life. The structure is built primarily of concrete and spans 2 sections, stretching 6.4 meters (21 feet) end to end. Daily traffic averages 3,838 vehicles, placing it in the moderately-trafficked tier of California bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show culvert at 4/9. The weakest component sits in poor condition. A component scored 4 or below, placing this bridge in the federal Poor condition category rather than declaring it unsafe or closed.
How SIERRA HWY compares
Age against the county: built in 1921, earlier than 3,520 of Los Angeles's 3,547 bridges with a recorded construction year (99%), against a county median build year of 1965. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across California bridges with a recorded inventory load rating (25,538 of 25,848 rated).
SIERRA HWY vs every rated California bridge
Inventory load rating (metric tons), FHWA NBI, this state
24 Top 84% higher than 16% of 25,538 bridges
rated California bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Los Angeles inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 3,547 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1921
- Last Reconstructed
- 1931
- Material
- Concrete
- Number of Spans
- 2
- Structure Length
- 6.4 m (21 ft)
- Deck Width
- 14.9 m (49 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 3,838 vehicles/day
- Structure Number
- 53C0389
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
SIERRA HWY is in the federal Poor condition category. That is a component-based result, not a closure order.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
- Compare SIERRA HWY against other structures in Los Angeles and across California. California bridges
- Noticed visible damage or a safety concern? Report it to the agency that owns the bridge, or call 911 in an emergency. How to report a bridge
Condition codes come straight from the FHWA National Bridge Inventory and are not a real-time safety judgment. Only the owning agency, a state DOT, county, or other owner, can post, restrict, or close a bridge.
Frequently Asked Questions
What do the condition ratings mean for SIERRA HWY?
SIERRA HWY in Los Angeles, California on the FHWA's 0–9 scale.
How often is SIERRA HWY inspected?
SIERRA HWY's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval. It carries about 3,838 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. SIERRA HWY is currently shown as Poor condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for SIERRA HWY?
SIERRA HWY has an NBI inventory load rating of 24.3 metric tons.
Who is responsible for maintaining SIERRA HWY?
SIERRA HWY is owned and maintained by County Highway Agency.
How old is SIERRA HWY and does age affect safety?
SIERRA HWY was built in 1921, making it 105 years old and last reconstructed in 1931.
Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A Poor condition rating is not a live declaration that a bridge is closed or unsafe for travel. For current closure, posting, or safety information, contact the responsible transportation agency.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.