State Route 55 (I-405 to I-5) Improvement Project

The California Department of Transportation (Caltrans) District 12, in cooperation with the Orange County Transportation Authority (OCTA), proposes to widen State Route 55 (SR-55) in both directions from just north of the Interstate 405 (I-405)/SR-55 Interchange to just south of the Interstate 5 (I-5)/SR-55 Interchange between Post Miles 6.4 and 10.3, traversing the cities of Santa Ana, Tustin, and Irvine in Orange County, California. The project purpose is to reduce traffic congestion and improve mobility and traffic operations in the project study area.

The information in the Supplemental Draft Inital Study/Environmental Assessment (IS/EA) is intended to supplement the Draft IS/EA previously prepared for this project that was released for public review on November 25, 2015. It focuses on the environmental impact evaluation and proposed avoidance, minimization and/or mitigation of potential impacts associated with the recently proposed Build Alternative 3 Modified (Alternative 3M).

Anticipated Schedule:
PA&ED – Present until Fall 2017
Design – Winter 2017 to Spring 2019
Construction – Construction Summer 2019

Public Notice

Due to unforseeable reasons, the Tustin Libary has been temporary closed for an unknown duration. In addition to the viewing locations provided in the Public Notice, the Supplemental Draft IS/EA will also be available at the Katie Wheeler Library, 13109 Old Myford Rod, Irvine, CA 92602.

Supplemental Draft Initial Study with Proposed Mitigated Negative Declaration/Environmental Assessment

Cover page/General Information/Title Page
Proposed Mitigated Negative Declaration
Table of Contents

Chapter 1 – Proposed Project
Chapter 2 - Affected Environment, Environmental Consequences, and Avoidance,
Minimization, and/or Mitigation Measures

2.1 Land Use
2.2 Growth
2.3 Community Impacts
2.4 Utilities and Emergency Services
2.5 Traffic and Transportation/Pedestrian and Bicycle Facilities
2.6 Visual/Aesthetics
2.7 Cultural Resources
2.8 Hydrology and Floodplain
2.9 Water Quality and Storm Water Runoff
2.10 Geology/Soils/Seismic/Topography
2.11 Paleontology
2.12 Hazardous Waste/Materials
2.13 Air Quality
2.14 Noise
2.15 Wetlands and Other Waters
2.16 Plant Species
2.17 Animal Species
2.18 Invasive Species
2.19 Cumulative Impacts
2.20 Climate Change
Chapter 3 – Comments and Coordination
Chapter 4 – List of Preparers
Chapter 5 - Distribution List

List of Appendices
Appendix A – CEQA Checklist
Appendix B – Resources Evaluated Relative to Requirements of Section 4(f)
Appendix C – Title VI Policy Statement
Appendix D – Summary of Relocation Benefits
Appendix E – Environmental Commitments Record
Appendix F – List of Technical Studies
Appendix G – 2016 RTP and 2015 FTIP Project Listings
Appendix H – FEMA FIRM

Supplemental Draft Project Report

Please submit your comments in writing no later than 5 pm, May 3 2017 to Charles Baker, Senior Environmental Planner, California Department of Transportation, District 12, Environmental Analysis- Specialist Branch, 1750 East 4th Street, Santa Ana, CA 92705 or via e-mail to:


For reference, the link to the previously circulated Draft IS/EA is provided below:

Draft Inital Study/Environmental Assessment (November 2015)

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Contact Information

General Information:

Phone: (657) 328-6000
Fax: (657) 328-6511

Physical Address:

California Department of Transportation
District 12
1750 East 4th Street, Suite 100
Santa Ana CA 92705

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