Interstate 405 over San Gabriel River
FairLos Angeles County, California · 07-LA-405-0.03-LBCH · Structure no. 53 1185
- Built
- 1964
- 61 years old
- Condition
- Fair
- inspected December 2024
- Type
- Box Beam or Girders - Multiple
- Concrete Continuous
- Length
- 390 ft
- 5 main spans
- Daily traffic
- 255,000
- 2021 count
- Owner
- State
- State Highway Agency
About this bridge
Interstate 405 over San Gabriel River is a concrete continuous box beam or girders - multiple carrying Interstate 405 over San Gabriel River in Los Angeles County, California. It was built in 1964, so it is 61 years old, older than the California average of 54.8 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 255,000 vehicles a day, roughly 5% of them trucks, projected to reach 316,127 by 2041. The structure is 390 ft (118.9 m) long and 130 ft wide. If it were closed, the detour would be 1.9 mi (3 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Interstate 405 over San Gabriel River built?
It was built in 1964, making it 61 years old in 2025.
What condition is Interstate 405 over San Gabriel River 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 December 2024.
How much traffic does Interstate 405 over San Gabriel River carry?
About 255,000 vehicles per day (2021 count), of which roughly 5% are trucks.
How long is Interstate 405 over San Gabriel River?
The structure is 390 ft (118.9 m) long with a longest span of 83 ft (25.3 m) and a deck 130 ft wide.
Who owns Interstate 405 over San Gabriel River?
It is owned by the State Highway Agency.