Project Description

The Interstate 405 (I-405) Improvement project from Interstate 5 to Harbor Boulevard is located in the Cities of Irvine, Costa Mesa, and a portion of unincorporated Orange County. The project is proposed to extend life expectancy of pavement, improve safety and efficiency for all modes of travelers and maintenance crews, enhance traffic operation, manage congestion, and provide ability to collect, analyze, and utilize data for systems performance along the I-405 corridor. 

Environmental Lead

Caltrans is the Lead Agency for the National Environmental Policy Act (NEPA), the environmental determination is a Categorical Exclusion (CE). Caltrans is also the Lead Agency for the California Environmental Quality Act (CEQA). The CEQA document is an Initial Study (IS), leading to a Negative Declaration (ND).

Project Cost

Total Project Cost: $163,900,000 

The project is funded through the 2020 State Highway Operation and Protection Program (SHOPP), a component under Senate Bill 1 (Road's repair and Accountability Act of 2017). Project funding is scheduled to be programmed in the 2022/2023 fiscal year. It will include both State and Federal funding

Project Timeline

  • March 15, 2020, Program Project
  • July 2020 Begin Environmental Studies
  • June 21 through July 21, 2021, Public Circulation Review Period
  • July 7, 2021, Virtual Public Hearing from 6:30 p.m. to 8:30 p.m.
  • October 21, 2021, Project Approval & Final Environmental Document 
  • September 2022 (anticipated) Project Design
  • March 2024 (anticipated) Begin Construction
  • March 2027 (anticipated) End Construction

What is Available

The Final Environmental Document is an Initial Study with Negative Declaration (IS/ND). The IS/ND is available below. Responses to public comments received during the public review period can be found in 'Appendix K - Response to Comments' within the Final Environmental Document. 


1. Final Environmental Document (IS/ND) Signed October 2021

Previous Documents

  1. Draft Environmental Document (IS/ND)
  2. Public Notice
  3. Project Fact Sheet 
  4. Frequently Asked Questions

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Contact the Project Team

For questions, please contact Sheilah Fortenberry, Public Information Officer, by email (Sheilah.Fortenberry@dot.ca.gov) or at (657) 328-6000.