Project History

I-405 Improvement Project - History 

Major Investment Study

A Major Investment Study (MIS) for the I-405 corridor from SR-73 to I-605 was completed in February 2006. The MIS addressed a variety of potential solutions to the mobility problems in the corridor. As part of the MIS process, the OCTA Board of Directors adopted a resolution supporting a Locally Preferred Strategy (LPS) of improvements to the I-405 corridor within the study area. A major consideration in the selection of the LPS was its limited ROW acquisition impacts.


I-405 MIS Timeline
Report: I-405 Major Investment Study (MIS) Final Report

Project Study Report

In 2006, voters approved Renewed Measure M (M2). A project to add one general purpose lane in each direction on I-405 was included in M2. In implementing this directive, the proposed project would need to make best use of the existing available freeway property, update interchanges, and replace all local overcrossings according to city and regional master plans. A Project Study Report/Project Development Support (PSR/PDS) document for this project, then called the “I-405 Widening Project,” was completed in July 2008. The PSR/PDS document describes the transportation problem, identifies the scope of viable alternatives, and provides an estimate of the project development support resources required. A Preliminary Environmental Assessment Report (PEAR) was also prepared as part of the PSR/PDS. This process resulted in a determination that a joint Environmental Impact Report (EIR) / Environmental Impact Statement (EIS) will be required in compliance with CEQA and NEPA, respectively (Department 2008).

Report: Project Study Report/Project Development Support

I-405 Scoping Meetings

Four Public Scoping Meetings were held in Fall 2009 to provide an early exchange of information and to give interested parties an opportunity to provide comments or identify concerns. Comments received at the meeting became part of the public record and will be considered in defining the scope of the project and developing the I-405 Improvement Project EIR/EIS.

View the scoping meeting materials.  

Christina Byrne

Project Contact

Christina Byrne
Manager of Community Outreach
(714) 560-5717
cbyrne@octa.net