BridgeSafety
Orange County, CA · Structure #55 0441

INTERSTATE 405

INTERSTATE 405 in 12-Ora-405-24.10-Slb, Orange County, California received a condition grade of F (0/100). Built in 1965, the bridge carries 255K vehicles daily on INTERSTATE 405 over Los Alamitos Channel. It is classified as structurally deficient.

F
0/100
0
Condition Score
255K
Daily Traffic
1965
Year Built
11m
Length

Component Ratings

DeckSerious
0/9

The riding surface — evaluated for cracking, spalling, and wear

SuperstructureSerious
0/9

Beams, girders, and trusses that support the deck

SubstructureSerious
0/9

Piers, abutments, and foundations below the deck

Bridge Details

Road
INTERSTATE 405
Crosses Over
Los Alamitos Channel
State
California
County
Orange County
Location
12-Ora-405-24.10-Slb
Year Built
1965
Age
61 years
Daily Traffic
255,000
Lanes
10
Length
11 meters
Owner
State Highway Agency
Structure Number
55 0441

About This Bridge

INTERSTATE 405 is a 61-year-old bridge located 12-Ora-405-24.10-Slb in Orange County, California. The bridge carries INTERSTATE 405 over Los Alamitos Channel with 10 traffic lanes, handling approximately 255K vehicles per day. Built in 1965, the structure spans 11 meters.

The bridge received a Condition Grade of F (0/100) based on Federal Highway Administration inspection data. Its deck is rated 0/9 (serious), superstructure 0/9 (serious), and substructure 0/9 (serious). The bridge is classified as structurally deficient, meaning at least one major component is rated 4 or below — this signals a need for repair or replacement but does not necessarily indicate an immediate safety hazard.

This bridge is owned and maintained by State Highway Agency.

Location Map

12-Ora-405-24.10-Slb, Orange County, California

33.785497, -118.092422

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Frequently Asked Questions

INTERSTATE 405 has a Condition Score of 0/100 (Grade F). Its deck is rated 0/9, superstructure 0/9, and substructure 0/9 on the NBI scale. The bridge is classified as structurally deficient.

INTERSTATE 405 was built in 1965, making it 61 years old. The average bridge age in the United States is 48 years.

INTERSTATE 405 carries approximately 255K vehicles per day (average daily traffic). The bridge has 10 traffic lanes. It is 11 meters long and located on INTERSTATE 405 in 12-Ora-405-24.10-Slb, Orange County, California.

Yes, INTERSTATE 405 is classified as structurally deficient because at least one of its primary components (deck, superstructure, or substructure) is rated 4 or below on the 0-9 NBI scale. This does not necessarily mean it is unsafe, but it requires significant repair or replacement.

INTERSTATE 405 is located 12-Ora-405-24.10-Slb in Orange County, California. The bridge carries INTERSTATE 405 over Los Alamitos Channel. Its coordinates are 33.785497, -118.092422. It is maintained by State Highway Agency.

INTERSTATE 405 carries INTERSTATE 405 over Los Alamitos Channel. The bridge is 11 meters long and was built in 1965.

Last updated:

Condition Score is calculated from deck (33%), superstructure (33%), and substructure (34%) NBI ratings with an age penalty for bridges over 50 years.