Interstate 405 over 166th Street
FairLos Angeles County, California · 07-LA-405-17.14-LNDL · Structure no. 53 1230
- Built
- 1962
- 63 years old, rebuilt 2003
- Condition
- Fair
- inspected October 2024
- Type
- Box Beam or Girders - Multiple
- Concrete Continuous
- Length
- 175 ft
- 3 main spans
- Daily traffic
- 268,300
- 2019 count
- Owner
- State
- State Highway Agency
About this bridge
Interstate 405 over 166th Street is a concrete continuous box beam or girders - multiple carrying Interstate 405 over 166th Street in Los Angeles County, California. It was built in 1962 and reconstructed in 2003, so it is 63 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 268,300 vehicles a day, roughly 5% of them trucks, projected to reach 309,310 by 2041. The structure is 175 ft (53.3 m) long and 141 ft wide. If it were closed, the detour would be 1.2 mi (2 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 | 8 Very Good | No problems noted. |
| Substructure | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Interstate 405 over 166th Street built?
It was built in 1962, making it 63 years old in 2025. It was reconstructed in 2003.
What condition is Interstate 405 over 166th Street 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 October 2024.
How much traffic does Interstate 405 over 166th Street carry?
About 268,300 vehicles per day (2019 count), of which roughly 5% are trucks.
How long is Interstate 405 over 166th Street?
The structure is 175 ft (53.3 m) long with a longest span of 96 ft (29.3 m) and a deck 141 ft wide.
Who owns Interstate 405 over 166th Street?
It is owned by the State Highway Agency.