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OC Go local tax dollars at work

I-405 Improvement Project

OCTA in cooperation with Caltrans is widening the San Diego Freeway (I-405) between SR-73 and I-605. The project will improve 16 miles of I-405 between the SR-73 freeway in Costa Mesa and I-605 near the L.A. County line.

OC Go local tax dollars at work

Project Overview

The general purpose lane portion of the project is an OC Go, formally Measure M (Orange County's half-cent transportation sales tax), project and will be funded by a combination of local, state and federal funds, with the express lanes portion of the project financed and paid for by those who choose to pay a toll and use the 405 Express Lanes.

Construction Updates

Construction Closures & Detours

For more information, please visit the construction section.

View map in a separate tab

bridge construction map (pdf)

Contact the 405 Community Outreach Team

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

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

Tiếng Việt: Để biết thêm thông tin về Dự Án Cải Thiện Xa Lộ I-405, vui lòng liên hệ với Gia Ly theo số 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.

16 Miles of Freeway

Improved for a quicker, more enjoyable driving experience

18 Bridges

Replaced and widened

Expand Metrolink

Added four more cycling routes

11 New Sidewalks

Added for pedestrian accessibility

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

Funding

The $1.9 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

$1.135 billion

State Funds

$90 million

Federal Funds

$46 million

federal TIFIA

$629 million

Project Partners

oc go
california climate investments
santa ana

Organizations

  • 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

Cities

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