FHWA NBI 2024 Inspection record Public-domain dataset

IMPERIAL HWY-N405

Carrying IMPERIAL HWY-N405 over IMPERIAL HIGHWAY

07-LA-405-R21.22-HAW, Los Angeles, California

Inventory: FHWA NBI 2024 · last ETL August 2026

FHWA NBI record, refreshed with each annual release.

Fair
32 t Inventory load rating Lower than 63% of rated California bridges

IMPERIAL HWY-N405 in Los Angeles, California sits above 37% of rated California bridges on inventory load rating (32 t), while its 1994 build year is earlier than 8% of Los Angeles's recorded-year cohort (3,547 bridges).

IMPERIAL HWY-N405 in Los Angeles, California is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1994, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 5. The lowest applicable rating sets the federal condition category, so this Fair 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:53 1241T

LATE-CENTURY · PRESTRESS · SINGLE-SPAN · DECK-LED · ARTERIAL-ADT · STANDARD-LOAD · CAT-FAIR

  • LATE-CENTURY 1980–1999
  • PRESTRESS Prestressed concrete
  • SINGLE-SPAN Single span
  • DECK-LED Deck-led
  • ARTERIAL-ADT Arterial ADT
  • STANDARD-LOAD Standard load
  • CAT-FAIR Fair

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: IMPERIAL HWY-N405

The IMPERIAL HWY-N405 bridge in Los Angeles, California carries IMPERIAL HWY-N405 over IMPERIAL HIGHWAY. It was built in 1994, making it 32 years old today. The structure is built primarily of prestressed concrete and spans 1 section, stretching 48.2 meters (158 feet) end to end. Daily traffic averages 2,000 vehicles, placing it in the moderately-trafficked tier of California bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show a deck rating of 5/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range.

How IMPERIAL HWY-N405 compares

▲ 0.3
Load rating vs California average (32.1 t; 25,538 of 25,848 rated)
3,547
Bridges in Los Angeles · 120 in Poor condition

Age against the county: built in 1994, earlier than 285 of Los Angeles's 3,547 bridges with a recorded construction year (8%), against a county median build year of 1965. This is one of the newer structures in its county.

IMPERIAL HWY-N405 32.4 t
California average (25,538 of 25,848 rated) 32.1 t

Live comparison across California bridges with a recorded inventory load rating (25,538 of 25,848 rated).

IMPERIAL HWY-N405 vs every rated California bridge

Inventory load rating (metric tons), FHWA NBI, this state

32 Top 63% higher than 37% 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

Deck
5/9
Fair (5–6)
Superstructure
7/9
Good (7–9)
Substructure
7/9
Good (7–9)
Inventory Load Rating
32.4 t
NBI inventory level (metric tons)
Overall Condition
Fair

Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.

Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.

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
1994
Material
Prestressed Concrete
Number of Spans
1
Structure Length
48.2 m (158 ft)
Deck Width
10.8 m (35 ft)
Owner
State Highway Agency
Avg Daily Traffic
2,000 vehicles/day
Structure Number
53 1241T

Condition Analysis

  • The deck (driving surface) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
  • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.

How to read this record

This page shows what the last federal inspection recorded, not whether IMPERIAL HWY-N405 is safe to cross today. Here is how to use it.

  • NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
  • Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
  • Compare IMPERIAL HWY-N405 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 IMPERIAL HWY-N405?

IMPERIAL HWY-N405 in Los Angeles, California has a deck rating of 5/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.

How often is IMPERIAL HWY-N405 inspected?

IMPERIAL HWY-N405'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 2,000 vehicles per day.

What does “structurally deficient” mean in older bridge reports?

FHWA retired that reported status beginning with the 2018 archive. IMPERIAL HWY-N405 is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.

What is the inventory load rating for IMPERIAL HWY-N405?

IMPERIAL HWY-N405 has an NBI inventory load rating of 32.4 metric tons.

Who is responsible for maintaining IMPERIAL HWY-N405?

IMPERIAL HWY-N405 is owned and maintained by State Highway Agency.

How old is IMPERIAL HWY-N405 and does age affect safety?

IMPERIAL HWY-N405 was built in 1994, making it 32 years old.

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.

Data sourced from the Federal Highway Administration National Bridge Inventory. See our methodology for details. Retrieved and formatted by PlainBridges

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Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.

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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.