Katella Avenue Interchange Improvements

The Orange County Transportation Authority (OCTA), in cooperation with the California Department of Transportation (Caltrans) District 12 and the City of Los Alamitos (City), proposes to improve the local interchange at Interstate 605 (I-605) and Katella Avenue, located in the western portion of the City which is located in western Orange County.  The proposed project is intended to improve freeway access and arterial connection, improve interchange traffic operations, enhance safety, and improve pedestrian and bicycle facilities within the interchange area.

Information in the Initial Study/Environmental Assessment (IS/EA) describes why the project is being proposed, the range of Build Alternatives being considered, the environmental impact evaluation, and proposed avoidance, minimization and/or mitigation of potential impacts associated with the proposed Build Alternatives.

Public Notice

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
 Affected Environment, Environmental Consequences, and Avoidance,
Minimization, and/or Mitigation Measures

2.1.1 Land Use
2.1.2 Growth
2.1.3 Community Impacts
2.1.4 Utilities and Emergency Services
2.1.5 Traffic and Transportation/Pedestrian and Bicycle Facilities
2.1.6 Visual/Aesthetics
2.1.7 Cultural Resources
2.2.1 Hydrology and Floodplain
2.2.2 Water Quality and Storm Water Runoff
2.2.3 Geology/Soils/Seismic/Topography
2.2.4 Paleontology
2.2.5 Hazardous Waste/Materials
2.2.6 Air Quality
2.2.7 Noise
2.3.1 Wetlands and Other Waters
2.3.2 Animal Species
2.3.3 Invasive Species
2.4 Cumulative Impacts
CHAPTER 3 - CEQA Checklist
3.1 Determining Significance Under CEQA
3.2 CEQA Environmental Checklist
3.3 Climate Change
- Comments and Coordination
CHAPTER 5 - List of Preparers
CHAPTER 6 - Distribution List

Appendix A - Section 4(f): No-Use Determination
Appendix B - Title VI Policy Statement
Appendix C - Transportation Conformity Working Group Determination
Appendix D - Avoidance, Minimization, and/or Mitigation Summary
Appendix E - List of Acronyms
Appendix F - RTP/FTIP Listing
Appendix G - Memo/Comparison of Jurisdictional Delineation Results

Noise Study Report (September 2017)
Paleontological Identification Report/Evaluation (Apil 2017)
Phase 1 Initial Site Assessment (February 2015)
Water Quality Assessment Report (November 2017)
Visual Resources Technical Memorandum (July 2017)
Traffic Study (October 2017)
Historic Property Survey Report (October 2017)
Location Hydraulic Study (April 2017)
Air Quality Assessment (August 2017)
District Preliminary Geotechnical Report (July 2017)
Natural Environment Study (Minimal Impacts) and Jursidicitonal Delineation (June 2017)

We would like to hear what you think of the proposed project. If you have any comments about the proposed project, please attend the public meeting on April, 24, 2018 at the Los Alamitos Community Center, 10911 Oak Street, Los Alamitos, CA 90720, and/or submit your comments in writing no later than 5 pm, May 8, 2018 to Gabriela Duran, California Department of Transportation, District 12, Environmental Analysis, 1750 East 4th Street, Santa Ana, CA 92705 or via e-mail to:


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