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OC Go local tax dollars at work

I-405 Improvement Project

OCTA in cooperation with Caltrans is improving 16 miles of the San Diego Freeway (I-405) between State Route 73 (SR-73) and Interstate 605 (I-605). It also will construct the 405 Express Lanes from SR-73 to I-605. The new express lanes – incorporating the existing carpool lanes and connectors that opened in 2014 – will be two lanes in each direction.

OC Go local tax dollars at work

Faster Future

Alert icon Construction Updates
Play icon Neighborhood Meetings

Anticipated Milestone Dates

Remaining Bridges

Anticipated Opening

Goldenwest StreetEarly 2023
Ward StreetEarly 2023
Bolsa AvenueEarly 2023
Warner AvenueMid-2023
Brookhurst StreetMid-2023
Springdale StreetMid-2023
Newland StreetMid-2023
I-405/SR-73 ConnectorMid-2023 *
*The I-405/SR-73 Connector construction is anticipated to be complete in mid-2023 however, it will not be open to traffic until the Express Lanes are completed in late 2023.

I-405 Improvement Project Design-Build Completion: Late 2023

Contact the 405 Community Outreach Team


If you have questions, please contact the Outreach Team by calling 888-400-8994

Para obtener más información sobre el Proyecto de Ampliación en el I-405, llame al 888-400-8994

Để biết thêm thông tin về Dự Án Cải Thiện Xa Lộ I-405, xin vui lòng liên lạc cô Gia Lý theo đường dây tiếng Việt 888-662-6569

Project by the Numbers

Once completed, the 405 Improvement Project will allow Orange County to keep pace with expected job, housing and population growth, while providing safe and reliable multimodal travel throughout the region.

Destination A to Destination B

16 Miles of Freeway

Improved for a quicker, more enjoyable driving experience

Bridge over freeway lanes

18 Bridges

Replaced and improved

Man riding a bike

11 New Bike Lanes

Added for more cycling routes

Man walking on the sidewalk

11 New Sidewalks

Added for pedestrian accessibility

Man in hard hat

40,000+ Jobs

Created during the entire life of the project


6 Corridor Cities

Plus the community of Rossmoor collaborating to keep traffic moving during construction


The $2.08 billion OC Go project, Measure M, being constructed in cooperation with Caltrans, will be funded mostly through a combination of local, state and federal funds, with the express lanes portion of the Project paid for by those who choose to pay a toll and use the 405 Express Lanes.

OC go sales tax funds

$1.3 billion

State Funds

$90 million

federal TIFIA

$629 million

Federal Funds

$46 million

Project Partners

oc go
Federal Highway Administration

Federal Highway

santa ana


  • OCTA
  • Caltrans
  • FHWA
  • 40 separate utility owners
  • Orange County Flood Control
  • Union Pacific Railroad
  • Army Corps of Engineers
  • U.S. Navy
  • Emergency service providers such as police and fire


  • Costa Mesa
  • Fountain Valley
  • Westminster
  • Huntington Beach
  • Garden Grove
  • Long Beach
  • Los Alamitos
  • Seal Beach
  • Community of Rossmoor
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