2. Final Environmental Impact Report (FEIR No. 357) with Appendices — Anaheim City Council, December 9, 2025 (part 1 of 4)

ATTACHMENT NO. 2
OC River Walk Project
Final Environmental Impact Report No. 357 with Appendices • Final Environmental Impact Report No. 357:
https://www.anaheim.net/DocumentCenter/View/67076/OCRW_FEIR_Nov2025?bidId= • Final Environmental Impact Report No. 357 Appendices:
o Appendix A - Initial Study / Notice of Preparation (IS/NOP) https://www.anaheim.net/DocumentCenter/View/67077/App-A_IS-NOP?bidId= o Appendix B - NOP Comments
https://www.anaheim.net/DocumentCenter/View/67078/App-B_NOPComments?bidId= o Appendix C - Air Quality / GHG Data
https://www.anaheim.net/DocumentCenter/View/67079/App-C_AQ-GHGData?bidId= o Appendix D - Biological Resources Technical Report
https://www.anaheim.net/DocumentCenter/View/67080/App-D_BRTR?bidId= o Appendix E - Cultural Memo
https://www.anaheim.net/DocumentCenter/View/67081/App-E_CulturalMemo?bidId= o Appendix F - Geotechnical Report
https://www.anaheim.net/DocumentCenter/View/67082/App-F_GeoTech?bidId= o Appendix G - Hydrology Report
https://www.anaheim.net/DocumentCenter/View/67083/AppG_HydrologyReport?bidId= o Appendix H - Noise Data
https://www.anaheim.net/DocumentCenter/View/67084/App-H_Noise-Data?bidId= o Appendix I - VMT Screening Memo
https://www.anaheim.net/DocumentCenter/View/67085/App-I_VMT-ScreeningMemo?bidId= FINAL
Environmental Impact Report No. 357
OC River Walk Project
November 2025
Prepared for:

City of Anaheim
Community Services Department, Parks Division
200 South Anaheim Boulevard, Suite 433
Anaheim, California 92805
Contact: Ana Straabe, Principal Project Planner
(714) 765-4463
[email protected]
Prepared by:
101 Progress, Suite 250
Irvine, California 92618
Contact: William Halligan, Esq., Senior Director/Senior Environmental Counsel (949) 655-3900
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Table of Contents
Final EIR No. 357 i November 2025
OC River Walk Project
Table of Contents
Acronyms and Abbreviations ..................................................................................................vii Chapter ES Executive Summary .........................................................................................ES-1 ES.1 Overview....................................................................................................ES-1 ES.2 Project Description ....................................................................................ES-1 ES.3 Project Objectives......................................................................................ES-6 ES.4 Project Impacts..........................................................................................ES-6 ES.5 Summary of Environmental Impacts and Mitigation Measures .................ES-7 ES.6 Alternatives to the Proposed Project .......................................................ES-22 ES.7 Potential Areas of Controversy and Issues to Be Resolved ....................ES-23 Chapter 1 Introduction .........................................................................................................1-1

1.1 Project Overview ..........................................................................................1-1

1.2 Project Background ......................................................................................1-1

1.3 Purpose and Use of the Environmental Impact Report ................................1-2

1.4 Lead, Responsible, and Trustee Agencies...................................................1-3

1.4.1 Lead Agency.....................................................................................1-3

1.4.2 Responsible and Trustee Agencies ..................................................1-3

1.5 Environmental Impact Report Review Process ............................................1-6

1.5.1 Notice of Preparation ........................................................................1-6

1.5.2 Draft Environmental Impact Report and Public Review..................1-17

1.5.3 Final Environmental Impact Report and Certification .....................1-18

1.6 Documents Incorporated by Reference......................................................1-18

1.7 Scope of the Environmental Impact Report................................................1-19

1.8 Organization of the Environmental Impact Report......................................1-20 Chapter 2 Project Description .............................................................................................2-1

2.1 Project Location and Setting.........................................................................2-1

2.1.1 Existing Land Uses ...........................................................................2-2

2.1.2 Surrounding Land Uses ....................................................................2-3

2.2 Project Objectives.........................................................................................2-4

2.3 Project Background and Purpose.................................................................2-5

2.3.1 Orange County Water District Groundwater Replenishment System Turnout Structure.................................................................2-6

2.4 Project Components .....................................................................................2-7

2.4.1 Project Construction .......................................................................2-18

2.5 Discretionary Actions..................................................................................2-18

2.5.1 Other Agency Approvals.................................................................2-18 Table of Contents
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Chapter 3 Environmental Setting ........................................................................................3-1

3.1 Regional Environmental Setting ...................................................................3-1

3.1.1 Regional Location .............................................................................3-1

3.1.2 Regional Planning Considerations....................................................3-1

3.2 Local Environmental Setting .........................................................................3-4

3.2.1 Project Location ................................................................................3-4

3.2.2 General Plan and Zoning ..................................................................3-5

3.2.3 Public Services and Utilities..............................................................3-5

3.3 Assumptions Regarding Cumulative Impacts...............................................3-5 Chapter 4 Environmental Analysis......................................................................................4-1

4.1 Air Quality ..................................................................................................4.1-1

4.1.1 Environmental Setting....................................................................4.1-1

4.1.2 Thresholds of Significance...........................................................4.1-10

4.1.3 Plans, Programs, and Policies.....................................................4.1-11

4.1.4 Environmental Impacts ................................................................4.1-11

4.1.5 Cumulative Impacts .....................................................................4.1-15

4.1.6 Level of Significance Before Mitigation........................................4.1-16

4.1.7 Mitigation Measures.....................................................................4.1-16

4.1.8 Level of Significance After Mitigation...........................................4.1-16

4.2 Biological Resources .................................................................................4.2-1

4.2.1 Environmental Setting....................................................................4.2-1

4.2.2 Thresholds of Significance...........................................................4.2-22

4.2.3 Plans, Programs, and Policies.....................................................4.2-23

4.2.4 Environmental Impacts ................................................................4.2-24

4.2.5 Cumulative Impacts .....................................................................4.2-32

4.2.6 Level of Significance Before Mitigation........................................4.2-33

4.2.7 Mitigation Measures.....................................................................4.2-34

4.2.8 Level of Significance After Mitigation...........................................4.2-40

4.3 Cultural Resources ....................................................................................4.3-1

4.3.1 Environmental Setting....................................................................4.3-1

4.3.2 Thresholds of Significance...........................................................4.3-18

4.3.3 Plans, Programs, and Policies.....................................................4.3-18

4.3.4 Environmental Impacts ................................................................4.3-18

4.3.5 Cumulative Impacts .....................................................................4.3-20

4.3.6 Level of Significance Before Mitigation........................................4.3-20

4.3.7 Mitigation Measures.....................................................................4.3-21

4.3.8 Level of Significance After Mitigation...........................................4.3-21

4.4 Geology and Soils .....................................................................................4.4-1

4.4.1 Environmental Setting....................................................................4.4-1

4.4.2 Thresholds of Significance.............................................................4.4-8 Table of Contents
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4.4.3 Plans, Programs, and Policies.......................................................4.4-8

4.4.4 Environmental Impacts ................................................................4.4-11

4.4.5 Cumulative Impacts .....................................................................4.4-18

4.4.6 Level of Significance Before Mitigation........................................4.4-19

4.4.7 Mitigation Measures.....................................................................4.4-20

4.4.8 Level of Significance After Mitigation...........................................4.4-20

4.5 Greenhouse Gas Emissions......................................................................4.5-1

4.5.1 Environmental Setting....................................................................4.5-1

4.5.2 Thresholds of Significance.............................................................4.5-9

4.5.3 Plans, Programs, and Policies.......................................................4.5-9

4.5.4 Environmental Impacts ..................................................................4.5-9

4.5.5 Cumulative Impacts .....................................................................4.5-10

4.5.6 Level of Significance Before Mitigation........................................4.5-11

4.5.7 Mitigation Measures.....................................................................4.5-11

4.5.8 Level of Significance After Mitigation...........................................4.5-11

4.6 Hazards and Hazardous Materials ............................................................4.6-1

4.6.1 Environmental Setting....................................................................4.6-1

4.6.2 Thresholds of Significance.............................................................4.6-8

4.6.3 Plans, Programs, and Policies.......................................................4.6-9

4.6.4 Environmental Impacts ..................................................................4.6-9

4.6.5 Cumulative Impacts .....................................................................4.6-11

4.6.6 Level of Significance Before Mitigation........................................4.6-12

4.6.7 Mitigation Measures.....................................................................4.6-12

4.6.8 Level of Significance After Mitigation...........................................4.6-12

4.7 Hydrology and Water Quality.....................................................................4.7-1

4.7.1 Environmental Setting....................................................................4.7-1

4.7.2 Thresholds of Significance...........................................................4.7-12

4.7.3 Plans, Programs, and Policies.....................................................4.7-13

4.7.4 Environmental Impacts ................................................................4.7-14

4.7.5 Cumulative Impacts .....................................................................4.7-25

4.7.6 Level of Significance Before Mitigation........................................4.7-27

4.7.7 Mitigation Measures.....................................................................4.7-28

4.7.8 Level of Significance After Mitigation...........................................4.7-29

4.8 Noise .........................................................................................................4.8-1

4.8.1 Environmental Setting....................................................................4.8-1

4.8.2 Thresholds of Significance...........................................................4.8-10

4.8.3 Plans, Programs, and Policies.....................................................4.8-11

4.8.4 Environmental Impacts ................................................................4.8-11

4.8.5 Cumulative Impacts .....................................................................4.8-17

4.8.6 Level of Significance Before Mitigation........................................4.8-18 Table of Contents
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4.8.7 Mitigation Measures.....................................................................4.8-18

4.8.8 Level of Significance After Mitigation...........................................4.8-19

4.9 Transportation ...........................................................................................4.9-1

4.9.1 Environmental Setting....................................................................4.9-1

4.9.2 Thresholds of Significance...........................................................4.9-10

4.9.3 Plans, Programs, and Policies.....................................................4.9-11

4.9.4 Environmental Impacts ................................................................4.9-11

4.9.5 Cumulative Impacts .....................................................................4.9-12

4.9.6 Level of Significance Before Mitigation........................................4.9-13

4.9.7 Mitigation Measures.....................................................................4.9-13

4.9.8 Level of Significance After Mitigation...........................................4.9-13

4.10 Tribal Cultural Resources ........................................................................4.10-1

4.10.1 Environmental Setting..................................................................4.10-1

4.10.2 Thresholds of Significance...........................................................4.10-6

4.10.3 Plans, Programs, and Policies.....................................................4.10-6

4.10.4 Environmental Impacts ................................................................4.10-7

4.10.5 Cumulative Impacts .....................................................................4.10-8

4.10.6 Level of Significance Before Mitigation........................................4.10-8

4.10.7 Mitigation Measures.....................................................................4.10-8

4.10.8 Level of Significance After Mitigation.........................................4.10-10 Chapter 5 Alternatives..........................................................................................................5-1

5.1 Significant and Unavoidable Impacts ...........................................................5-1

5.2 Project Objectives.........................................................................................5-2

5.3 Alternatives Considered But Rejected..........................................................5-2

5.3.1 Alternative Sites................................................................................5-2

5.3.2 No Impoundment Alternative ............................................................5-3

5.4 Analysis of Project Alternatives Selected for Evaluation ..............................5-3

5.4.1 Alternative 1: No Project/No Improvements Alternative....................5-4

5.4.2 Alternative 2: Group A and C Impoundments and Trails Alternative ....5-6

5.5 Environmentally Superior Alternative ...........................................................5-9 Chapter 6 Other CEQA Considerations ..............................................................................6-1

6.1 Significant and Unavoidable Environmental Impacts ...................................6-1

6.2 Significant Irreversible Changes Due to the Proposed Project.....................6-1

6.3 Growth-Inducing Impacts..............................................................................6-3

6.4 Effects Found Not to Be Significant..............................................................6-4 Chapter 7 Individuals and Agencies Consulted.................................................................7-1

7.1 Lead Agency.................................................................................................7-1

7.2 Consultants...................................................................................................7-1 Chapter 8 References ...........................................................................................................8-1 Table of Contents
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Figures
Figure 2-1. Regional Location..................................................................................................2-23 Figure 2-2. Local Vicinity..........................................................................................................2-25 Figure 2-3. Project Site and Adjacent Ownerships ..................................................................2-27 Figure 2-4. Existing Project Site Views ....................................................................................2-29 Figure 2-4a. Existing Project Site Views ..................................................................................2-31 Figure 2-4b. Existing Project Site Views ..................................................................................2-33 Figure 2-4c. Existing Project Site Views ..................................................................................2-35 Figure 2-4d. Existing Project Site Views ..................................................................................2-37 Figure 2-5. Existing Condition – Surface .................................................................................2-39 Figure 2-6. Existing Condition – Underground.........................................................................2-41 Figure 2-7. Proposed Impoundments and Trail Improvements................................................2-43 Figure 2-8. Overall Project Elements .......................................................................................2-45 Figure 2-8a. Proposed Improvements – Group A....................................................................2-47 Figure 2-8b. Proposed Improvements – Group B....................................................................2-49 Figure 2-8c. Proposed Improvements – Group C ....................................................................2-51 Figure 2-8d. Proposed Improvements – Group D....................................................................2-53 Figure 2-9. Rubber Impoundments ..........................................................................................2-55 Figure 2-10. Trail Circulation System.......................................................................................2-57 Figure 2-11. Project Rendering – South of Cerritos River Access...........................................2-59 Figure 2-12. Project Rendering – South of SR-57 Freeway ....................................................2-61 Figure 2-13. Off-Site Improvements.........................................................................................2-63 Figure 4.2-1. National Wetlands Inventory Results...............................................................4.2-41 Figure 4.2-2. Vegetation Communities and Land Cover Types ............................................4.2-43 Figure 4.2-3. Aquatic Resources ..........................................................................................4.2-45 Tables
Table ES-1. OC River Walk Conceptual Master Plan Elements.............................................ES-2 Table ES-2. Summary of Environmental Impacts and Mitigation Measures...........................ES-8 Table 1-1. NOP Comment Summary .........................................................................................1-6 Table 2-1. OC River Walk Conceptual Master Plan Elements...................................................2-7 Table 4.1-1. National and California Ambient Air Quality Standards ......................................4.1-2 Table 4.1-2. South Coast Air Quality Management District Attainment Status .......................4.1-3 Table 4.1-3. Air Quality Monitoring Summary .......................................................................4.1-10 Table 4.1-4. Construction-Related Regional Pollutant Emissions (pounds/day)1 .................4.1-12 Table 4.1-5. Local Construction Emissions at the Nearest Receptor ...................................4.1-14 Table 4.2-1. Existing Land Use Acreages.............................................................................4.2-11 Table 4.2-2. Vegetation Communities and Land Cover Types .............................................4.2-11 Table 4.2-3. Jurisdictional Aquatic Resources......................................................................4.2-14 Table of Contents
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Table 4.2-4. Sensitive Plant and Wildlife Species with Potential to Occur............................4.2-15 Table 4.3-1. Prior Studies within 0.50-Mile Buffer.................................................................4.3-14 Table 4.3-2. Previously Recorded Cultural Resources within 0.50-Mile Buffer.....................4.3-16 Table 4.7-1. Existing Bridge Description...............................................................................4.7-12 Table 4.8-1. Federal Transit Administration Groundborne Vibration Impact Criteria ..............4.8-1 Table 4.8-2. Anaheim Land Use Compatibility for Community Noise Exposure (Exterior) (Figure N-2 of the Anaheim General Plan).........................................................4.8-4 Table 4.8-3. Typical A-Weighted Noise Levels .......................................................................4.8-6 Table 4.8-4. Typical Levels of Groundborne Vibration............................................................4.8-9 Table 4.8-5. Human Response to Different Levels of Groundborne Vibration........................4.8-9 Table 4.8-6. Typical Construction Noise Levels....................................................................4.8-12 Table 4.8-7. Vibration Source Levels for Construction Equipment .......................................4.8-16 Table 4.9-1. Trip Generation.................................................................................................4.9-10 Table 5-1. Comparison of Potentially Significant Impacts for Alternatives to the Project ........5-10 Table 6-1. Effects Found Not to Be Significant ..........................................................................6-4 Appendices
Appendix A. Initial Study/Notice of Preparation
Appendix B. NOP Comments
Appendix C. Air Quality/GHG Data
Appendix D. Biological Resources Technical Report
Appendix E. Cultural Memo
Appendix F. Geotechnical Report
Appendix G. Hydrology Report
Appendix H. Noise Data
Appendix I. VMT Screening Memo
Acronyms and Abbreviations
Final EIR No. 357 vii November 2025
OC River Walk Project
Acronyms and Abbreviations
°F degree Fahrenheit
ACC Arena Corporate Center
ADA Americans with Disabilities Act
ADT average daily traffic
ADWF average dry weather flow
AFG accelerated forecast growth
AFY acre-feet per year
AIA Airport Influence Area
ALUC Airport Land Use Commission
ALUCP Airport Land Use Compatibility Plan
AMI average median income
amsl above mean sea level
APE area of potential effect
AQMP Air Quality Management Plans
ARDR Aquatic Resources Delineation Report
ARTIC Anaheim Regional Transportation Intermodal Center ASMD area-specific management directive
AST Bridge Atchison, Topeka & Santa Fe Railroad Bridge
AT Active Transportation
BAU business-as-usual
BCE Before Common Era
BMP best management practice
BRTR Biological Resources Technical Report
Btu British thermal units
C&D construction and demolition
CA Community Amenities
CAA Clean Air Act
CAAQS California has adopted ambient air quality standards CAFE Corporate Average Fuel Economy
CAL FIRE California Department of Forestry and Fire Protection CalEEMod California Emissions Estimator Model
CalEPA California Environmental Protection Agency
CALGreen California Green Building Standards Code
Cal-OSHA California Occupational Safety and Health Administration CalRecycle California Department of Resources Recycling and Recovery Caltrans California Department of Transportation
CARB California Air Resources Board
CBC California Building Code
CCAA California Clean Air Act
CCR California Code of Regulations
CDFW California Department of Fish and Wildlife
CDMG California Department of Conservation, Division of Mines and Geology
CE Common Era
Acronyms and Abbreviations
Final EIR No. 357 viii November 2025
OC River Walk Project
CEC California Energy Commission
CEQA California Environmental Quality Act
CESA California Endangered Species Act
CFG California Fish and Game
CFPP Construction Fire Prevention Plan
CFR Code of Federal Regulations
cfs cubic feet per second
CIDH cast-in-drilled-hole
CIP Capital Improvement Program
cmbs centimeters below surface
CMP Congestion Management Program
CNEL community noise equivalent level
CNPS California Native Plant Society
CO carbon monoxide
CO2 carbon dioxide
CPUC California Public Utilities Commission
CRHR California Register of Historical Resources
CRPR California Rare Plant Rank
CUPA Certified Unified Program Agency
CWA Clean Water Act
DBH diameter at breast height
DOF California Department of Finance
DTSC Department of Toxic Substances Control
DWR California Department of Water Resources
EDR Environmental Data Resources, Inc.

EIR Environmental Impact Report
EO Executive Order
EPCRA Emergency Planning and Community Right-to-Know Act of 1986 ESA Environmental Site Assessment
EV electric vehicle
FAA Federal Aviation Administration
FEMA Federal Emergency Management Agency
FESA federal Endangered Species Act
FHSZ fire hazard severity zone
FHWA Federal Highway Administration
FMZ fuel modification zone
FRAP Fire and Resource Assessment Program
FTA Federal Transit Administration
FTIP Federal Transportation Improvement Program
GCC global climate change
GHG greenhouse gas
GIS geographic information systems
GPA Global Positioning System
gpd gallons per day
gpm gallons per minute
GSA groundwater sustainability agency
Acronyms and Abbreviations
Final EIR No. 357 ix November 2025
OC River Walk Project
GWRS groundwater replenishment system
H2S hydrogen sulfide
HCM Highway Capacity Manual
HCP Habitat Conservation Plan
HMP Hydromodification Management Plan
HOA homeowners association
HOV high-occupancy vehicle
HRA Health Risk Assessment
HU hydraulic unit
HVAC heating, ventilation, and air conditioning
I- Interstate
IEPR Integrated Energy Policy Report
IRP Integrated Water Resources Plan
IS/MND Initial Study/Mitigated Negative Declaration
ITE Institute of Transportation Engineers
JRMP Jurisdictional Runoff Management Program
KVP key vantage point
kWh kilowatt-hours
LCFS low carbon fuel standards
LED light-emitting diode
LEED Leadership in Energy and Environmental Design
LHMP Local Hazard Mitigation Plan
LIC Land Use and Climate Innovation
LOS level of service
LOSSAN Corridor Los Angeles-San Diego-San Luis Obispo Rail Corridor LPG liquefied petroleum gas
LST Localized Significance Thresholds
LUST leaking underground storage tank
MBTA Migratory Bird Treaty Act
MGD million gallons per day
MMBtu million British thermal units
Model Ordinance Model Water Efficient Landscaping Ordinance MOE measure of effectiveness
mph miles per hour
MPO metropolitan planning organization
MRZ Mineral Resource Zone
MS4s municipal separate storm sewer systems
MSCP Multiple Species Conservation Program
MT/SP metric tons per service population
NAAQS National Ambient Air Quality Standards
NAGPRA Native American Graves Protection and Repatriation Act NAHC Native American Heritage Commission
NCCP Natural Community Conservation Program
NCCPA Natural Community Conservation Planning Act
NEHRP National Earthquake Hazards Reduction Program
NHD National Hydrography Dataset
Acronyms and Abbreviations
Final EIR No. 357 x November 2025
OC River Walk Project
NHTSA National Highway Traffic Safety Administration
NMFS National Marine Fisheries Service
NO nitric oxide
NO2 nitrogen dioxide
NOP Notice of Preparation
NPDES National Pollutant Discharge Elimination System
NRHP National Register of Historic Places
NSLU noise-sensitive land use
NWI National Wetlands Inventory
O3 ozone
OCFCD Orange County Flood Control District
OCPW Orange County Public Works
OCSAN Orange County Sanitation District
OCTA Orange County Transportation Authority
OCWD Orange County Water District
OPR Governor’s Office of Planning and Research
OSHA Occupational Safety and Health Administration
PM2.5 fine particulate matter
PM10 respirable particulate matter
PPP Plans, Programs, and Policies
PPV peak particle velocity
PRC California Public Resources Code
project OC River Walk Project
psi pounds per square inch
PV photovoltaic
PVC polyvinyl chloride
PWWF peak wet weather flow
RA River Activation
RCNM Roadway Construction Noise Model
RCRA Resource Conservation and Recovery Act
RFS Renewable Fuel Standard
RMS root mean square
RPS Renewable Portfolio Standard
RWQCB Regional Water Quality Control Board
SARI Santa Ana River Interceptor
SART Santa Ana River Trail
SB Senate Bill
SCAB South Coast Air Basin
SCAG Southern California Association of Governments
SCAQMD South Coast Air Quality Management District
SCE Southern California Edison
SCIC South Coastal Information Center
SEMS Standardized Emergency Management System
SHPO State Historic Preservation Office
SIP State Implementation Plan
SMARA Surface Mining and Reclamation Act
Acronyms and Abbreviations
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OC River Walk Project
SO2 sulfur dioxide
SR- State Route
STIP State Transportation Improvement Program
STP shovel test pit
SWIS Solid Waste Information System
SWPPP Stormwater Pollution Prevention Plan
SWRCB State Water Resources Control Board
TAC toxic air contaminant
TCR Tribal Cultural Resource
TDM Transportation Demand Management
TGD Technical Guidance Document
TIA Transportation Impact Analysis
TMDL total maximum daily load
UBC Uniform Building Code
UPRR Union Pacific Railroad
USACE U.S. Army Corps of Engineers
USDA U.S. Department of Agriculture
USEPA U.S. Environmental Protection Agency
USFWS U.S. Fish and Wildlife Service
USGS U.S. Geological Survey
UST underground storage tank
UTV utility task vehicle
v/c volume to capacity
VdB vibration decibel
VHFHSZ Very High Fire Hazard Severity Zone
VMT vehicle miles traveled
VOC volatile organic compound
WL Watch List
WQMP Water Quality Management Plan
WSEL water surface elevation
WUI wildland-urban interface
ZEV zero-emission vehicle
Acronyms and Abbreviations
Final EIR No. 357 xii November 2025
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Chapter ES: Executive Summary
Final EIR No. 357 ES-1 November 2025
OC River Walk Project
Chapter ES Executive Summary
This chapter is an executive summary of the Environmental Impact Report (EIR) for OC River Walk Project (project) prepared in compliance with the California Environmental Quality Act (CEQA).

This chapter highlights the major areas of importance in the environmental analysis for the proposed project as required by CEQA Guidelines, Section 15123, and also provides a brief description of the project, project objectives, project impacts and mitigation measures, alternatives to the project, and areas of controversy/issues raised by the public known to the City of Anaheim (lead agency).

ES.1 Overview
As required by CEQA, this EIR (1) assesses the potentially significant direct, indirect, and cumulative environmental effects of the proposed project; (2) identifies potential feasible means of avoiding or substantially lessening significant, adverse impacts; and (3) evaluates a range of reasonable alternatives to the project, including the required No Project Alternative. The City of Anaheim is the lead agency for the project evaluated in this EIR and, as such, has the principal responsibility for approving the project.

Pursuant to CEQA Guidelines, this EIR is a project EIR that evaluates the effects of the entire project at a project level. This EIR will be used by the City of Anaheim to evaluate the environmental implications of adopting the project. Once certified, this EIR will also be used to tier subsequent environmental analyses for future development projects. Once approved, the project will guide the redevelopment of the project site.

ES.2 Project Description
The project site is located along the Santa Ana River corridor, generally extending from Orangewood Avenue north to Ball Road and the existing Anaheim Coves at Burris Basin. It generally encompasses approximately a 2-mile stretch of the Santa Ana River, covering approximately 111 acres. It is approximately 15 miles upstream from the Pacific Ocean and adjacent to Angel Stadium, Anaheim Regional Transportation Intermodal Center (ARTIC), the Honda Center, and the Arena Corporate Center (ACC) buildings on the west side in the City of Anaheim. The ARTIC, the Honda Center, and the ACC buildings are all part of the OCVIBE Master Site Plan Project (OCVIBE Project). On the east side of the Santa Ana River, in the City of Orange, the project is near the Sandra Hutchens Regional Law Enforcement Training Center (a facility that includes a combat shooting range), the Orange County Public Works offices, the Stadium Promenade shopping mall, the Extended Stay America – Orange, and the Kinder Morgan Orange Terminal.

In 2021, the OC River Walk Engineering Feasibility Study identified 17 design opportunities along the Santa Ana River within the project site. The opportunities outlined in the Feasibility Study align with the U.S. Army Corps of Engineers Operating Principles, as well as the California State Chapter ES: Executive Summary
Final EIR No. 357 ES-2 November 2025
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Coastal Conservancy's Santa Ana River Conservancy Program goals of (1) protection and preservation of water resources through multi-benefit projects, (2) habitat and wildlife preservation and enhancement, and (3) equitable education and recreation access. The Feasibility Study served as the launching point for the OC River Walk Conceptual Master Plan and design documents for multiple projects within OC River Walk.

The OC River Walk Conceptual Master Plan consists of various multi-purpose improvements to transform the Santa Ana River corridor and portions of the existing Santa Ana River Trail (SART), along with related off-site improvements necessary for its implementation. The main components of the Conceptual Master Plan involve creating two water impoundments by installing three inflatable rubber dams, modifying the riverbanks, constructing two pedestrian/bike bridges, providing new trails, improving existing trails, creating new and protection of existing access ramps, constructing two new undercrossings on the west bank at the Union Pacific Railroad and the Metrolink railroad, providing enhanced community recreation amenities (e.g., terraced seating, nature play areas, parklets, plazas, gathering areas for large-scale events, festivals, and other activities, water access, kayak launch, etc.), and other improvements. These improvements would require the implementation of 19 project elements, which have been categorized into four groups:

Group A – Impoundments, Storm Drain Diversions, and Embankments; Group B – New Pedestrian/Bike Bridges; Group C – New Trails and Trail Improvements; and Group D – Enhanced Community Recreation Amenities, as shown Table ES-1, OC River Walk Conceptual Master Plan Elements, and on Figures 2-7, Proposed Impoundments and Trail Improvements; 2-8, Overall Project Elements; and 2-8a through 2-8d, Proposed Improvements Group A through D. The OC River Walk project conforms with the design goals and function of the SAR described in the USACE 1988 General Design Memorandum. The project design (e.g., levee design, vegetation, and freeboard, etc.) would be reviewed and permitted by the USACE and the Orange County Flood Control District (OCFCD) through the 408 permitting process. For CEQA analysis, it is assumed that these various components could be implemented simultaneously or at different stages within an approximately 10-year period tentatively scheduled between 2026 and 2036. The initial construction is expected to take approximately 24 to 36 months.

Table ES-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 Group A: Impoundments, Storm Drain Diversions, and Embankments

1. River Impoundments
1a North Impoundment and Inflatable Rubber Dam
3,000' length, 22 ac area,
110 AF volume
Rubber Dam: 8' x 300'
1b North Impoundment – Rubber Dam Concrete Foundation
310' x 24' x 2' = 700 CY reinforced concrete
10,000 CY of earthwork subgrade
preparation
1c North Impoundment – Rubber Dam Air Compressor, Controls, and Flow Bypass
10' x 10' x 7' precast concrete vault or
building (preferred)
Chapter ES: Executive Summary
Final EIR No. 357 ES-3 November 2025
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Table ES-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 1d South Impoundment and Inflatable Rubber Dam
1,700' length, 11.5 ac area,
90 AF volume
Rubber Dam: 10' x 300'
1e South Impoundment – Rubber Dam Concrete Foundation 310' x 24' x 2' = 700 CY reinforced concrete 10,000 CY of earthwork subgrade preparation
1f South Impoundment – Rubber Dam Air Compressor, Controls, and Flow Bypass
10' x 10' x 7' precast concrete vault or
building (preferred)
1g Collins Channel – Inflatable Rubber Dam Rubber Dam: 6' x 45' 1h Collins Channel – Rubber Dam Concrete Foundation
60' x 24' x 2' = 130 CY
1,500 CY of earthwork subgrade
preparation
1i Collins Channel – Rubber Dam Air Compressor and Controls 10' x 10' x 7' precast concrete vault or building (preferred)

2. Impoundment Evacuation Pumps 4 pumps at 5 MGD ea. (20 MGD total), 85 HP ea. (340 HP total)

3. Pipeline from Pump Station to GWRS Turnout
(N. of Orangewood Avenue to Burris Basin) 8,000 LF, 30-40" HDPE

4. GWRS Turnout – Concrete Flow Control Structure with
Dechlorination Facilities (Located at South End of Burris Basin) – Off-Site Improvement
50 MGD

5. Storm Drain Diversions (Dry-Weather Flow)
5a Anaheim – Storm Drain Outlets w/ Flap Gates 8 gates, 18"-54" 5b Anaheim – Diversion Manholes 8 manholes
5c Anaheim – Diversion Pump Stations 2 pump stations w/ 2 pumps ea., 125 GPM and 5 HP per pump
5d Anaheim – Storm Drain Diversion Pipe to Sewer 4-6" PVC pipe, 2,200 LF 5e Orange – Storm Drain Outlets w/ Flap Gates 7 gates, 18"-54" 5f Orange – In-Channel Diversion Structure at Collins Channel TBD 5g Orange – Diversion Manholes 7 manholes
5h Orange – Diversion Pump Stations
1 pump station w/ 2 pumps,
200 GPM and 7.5 HP per pump;
2 pump stations w/ 2 pumps ea., 125 GPM
and 5 HP per pump
5i Orange – Storm Drain Diversion Pipe to Sewer 4-6" PVC pipe, 7,250 LF 5j Wet Weather Storm Drain Diversion to Impoundments1 ±200 AF

6. River Embankments 9,600 LF total
6a North Impoundment Embankment 6,200 LF, 23' avg. height to 26' max, up to 33' at drop structure
6b South Impoundment Embankment 3,400 LF, 23' avg. height to 26' max, up to 33' at drop structure
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Table ES-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 Group B: New Pedestrian/Bike Bridges

1. Pedestrian/Bike Bridge North of Katella Avenue 400 LF, 36'-58' width, 3 River Piers

2. Pedestrian/Bike Bridge North of Orangewood Avenue 350 LF, 12'-18' width, 5 River Piers

3. Bridge Retaining Walls
3a New Pedestrian/Bike Bridge N. of Katella West Bank Retaining Wall #1 500 LF, <8' height
3b New Pedestrian/Bike Bridge N. of Katella West Bank Retaining Wall #2 500 LF, <8' height
3c New Pedestrian/Bike Bridge N. of Katella East Bank Retaining Wall #3 500 LF, <8' height
Group C: New Trails and Trail Improvements

1. Trail West Bank – Katella Avenue to Anaheim Coves 6,400 LF total, 18' typ. width 1a UPRR – Undercrossing (New Undercrossing) 500 LF, 20' typ. width 1b UPRR Undercrossing Retaining Wall 500 LF, <10' height 1c UPRR – At-Grade Crossing (Existing Maintenance Access) 100 LF, 18' typ. width 1d OC River Walk and River Road Retaining Wall 750 LF, <8' height 1e Ball Road Culvert Undercrossing (Existing 14x14 RCB) 800 LF, 18' typ. width 1f Ball Road Bridge Undercrossing w/ City and County and OCWD (Existing Maintenance Access) TBD
1g River Access/Kayak Ramp South of Cerritos (Existing Ramp) TBD 1h Interim UPRR Crossing at Phoenix Club Drive (Existing RR Crossing and New Interim Connection Trail) TBD
1i Replace Access Road Only (For New Pedestrian/Bike Bridge North of Katella Ave.) N/A

2. Trail West Bank – Katella Avenue to Orangewood Avenue 4,000 LF, 18' typ. width 2a Embankment Seating and Steps 350 LF
2b Metrolink RR Undercrossing (Existing Undercrossing) 800 LF, 20' typ. width 2c Metrolink Underpass Retaining Wall 900 LF, <12' height 2d River Walk South Embankment Seating and Steps 450 LF 2e SR-57 Underpass Trail Widening 400 LF
2f SR-57 Retaining Wall 400 LF, <14' height

3. Trail East Bank Katella Avenue to Ball Road 4,300 LF, 18' typ. width 3a Replace Access Road Only (For New Pedestrian/Bike Bridge North of Katella Avenue) N/A
3b Improve Trail w/ Terrace and Community Access 4,300 LF, 12'-40' width 3c East Bank Park/River Terrace Retaining Wall #1 500 LF, <8' height 3d City of Orange Water Recreation Opportunity1 N/A
Chapter ES: Executive Summary
Final EIR No. 357 ES-5 November 2025
OC River Walk Project
Table ES-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 3e East Bank Park/River Terrace Retaining Wall #2 1,000 LF, <8' height

4. Trail East Bank Katella to Orangewood: SART – Main Line Reroute to East Bank of River 4,000 LF, 18' typ. width
Group D: Enhanced Community Recreation Amenities

1. River Recreation – North Impoundment
1a Kayaking and Water Recreation Activities (kayak launch ramp is identified in Group C 1g.) 22 ac
1b Swimming / Wading Recreational Opportunity 1-3 ac
1c Recirculation and Water Feature Pumps1 1,000-5,000 GPM (1.5-7.5 MGD)
1d Water Feature Elements (Water show, water screen, etc.)1 TBD 1e Swimming Water Quality Pumps and Treatment1 5,000-10,000 GPM

2. River Recreation – South Impoundment
2a Kayaking and Water Recreation Activities 11.5 ac
2b Under SR-57 – Lighting and Other Amenities TBD
2c Recirculation and Water Feature Pumps1 1,000-5,000 GPM (1.5-7.5 MGD)
2d Water Feature Elements1 TBD

3. OCVIBE Lot B Parking Lot, Potential Future OC River Walk Park 2.2 ac

4. Park / River Terrace: East Bank North of Katella Avenue 4a East Bank (City of Orange) Katella Avenue to UPRR 8.3 ac 4b UPRR to Ball Road 2.2 ac

5. Riverbed Between Impoundments (future recreation TBD) 3.8 ac, 650 LF

6. Art / Education / Signage (Conceptual locations)
6a Iconic Signage1 TBD
6b Bridge Mural and Lighting at freeway underpass TBD
6c Mosaic / Art Installations TBD
6d Reflective Shade Canopies TBD
6e Zen Zone / Wildflower Spaces1 TBD
6f River Poetry Walk TBD
6g Interactive Educational Components TBD
6h Wayfinding Signage1 TBD
6i Conceptual Locations for Art/Signage Opportunities¹ TBD Notes: ac = acres; AF = acre-feet; CY = cubic yards; GPM = gallons per minute; HDPE = high- density polyethylene; HP = horsepower; LF = linear feet; MGD = million gallons per day; N/A = Not Applicable; TBD = to be determined; typ. = typical; UPRR = Union Pacific Railroad; All project dimensions and locations are approximate as of the time of EIR preparation and have been assumed for analysis purposes.
1 Project element is not specifically located at this time or encompasses the entire project site.

Additionally, all necessary new and/or upgrades to existing on- and off-site utilities and systems, such as electrical facilities, lighting, landscaping, irrigation, seating, and signage to implement various Chapter ES: Executive Summary
Final EIR No. 357 ES-6 November 2025
OC River Walk Project
components of the project, would be provided in compliance with applicable City of Anaheim and City of Orange rates, rules, and regulations; municipal codes; the California Green Building Standards Code; and any applicable engineering standards and specifications, as deemed necessary by the approving agency. The dimensions (e.g., lengths, heights, volumes) and locations specified in each element are approximate as of the time of EIR preparation and have been assumed for analysis purposes.

Public Law 84-99, Emergency Response to Natural Disasters, is the USACE’s basic authority to provide for emergency activities in support of State and Local governments prior to, during, and after a flood event. Under PL 84-99, the USACE can provide both emergency technical and direct assistance in response to flood and coastal storms, and can assist if there is a flood threat from damage caused by earthquakes to flood risk management projects. The SAR is currently eligible for Public Law 84-99 program coverage, and it should be noted that the project would not change this eligibility status.

ES.3 Project Objectives
In accordance with Section 15124(b) of the CEQA Guidelines, the City of Anaheim has identified the following objectives for the project:

1. Adopt the OC River Walk Conceptual Master Plan for OC River Walk Project to further enhance and accentuate existing recreational areas, facilitate pedestrian and bicycle access, and promote the use of the river corridor open space area for the community benefit.

2. Implement projects identified in the OC River Walk Conceptual Master Plan that will create visually appealing outdoor public amenities that will benefit and promote environmental and community health, recreation, safety, entertainment, wayfinding, art, education, cultural awareness, beauty, connectivity, water supply, economic, and natural resource needs.

3. Provide seamless and cohesive improvements across jurisdictions on the project site to benefit the public and the area’s aesthetics.

4. Implement projects to transform and improve the river and riverbed’s groundwater recharge potential and improve the river corridor’s ecology (flora and fauna).

5. Maintain and enhance flood protection capacity and resiliency.

6. Enhance connectivity and community access by leveraging the project site's location near ARTIC, major entertainment venues, and adjacent mixed-use developments.

ES.4 Project Impacts
This EIR examines the potential environmental effects of the proposed project, including information related to existing site conditions, analyses of the types and magnitude of individual and cumulative environmental impacts, and feasible mitigation measures that could reduce or avoid environmental impacts. In accordance with Appendix G of the CEQA Guidelines, the potential environmental effects of the proposed project were analyzed for the following environmental issue areas:

Chapter ES: Executive Summary
Final EIR No. 357 ES-7 November 2025
OC River Walk Project
• Air Quality
• Biological Resources
• Cultural Resources
• Geology and Soils
• Greenhouse Gas Emissions
• Hazards and Hazardous Materials
• Hydrology and Water Quality
• Noise
• Transportation
• Tribal Cultural Resources
Table ES-2, Summary of Environmental Impacts and Mitigation Measures, provides a summary of the project-level and cumulative environmental impacts that could result from implementation of the proposed project and feasible mitigation measures that could reduce or avoid environmental impacts. For each impact, Table ES-2 identifies the significance of the impact before mitigation (including which phase the mitigation is required), applicable mitigation measures, and the level of significance of the impact after implementation of the mitigation measures.

Other environmental issues identified in Appendix G of the CEQA Guidelines have been scoped out from further analysis, as they were determined to have no impact or less than significant impact in the Initial Study prepared during the Notice of Preparation process. The Notice of Preparation and the accompanying Initial Study were circulated for public review from March 23, 2023, through April 24, 2023, and are included as Appendix A to this Draft Environmental Impact Report (EIR). Environmental issues found to have no or less than significant impacts are also included in Section 6.4, Effects Found Not to be Significant.

ES.5 Summary of Environmental Impacts and Mitigation Measures Table ES-2 summarizes the impacts and mitigation measures addressed in Sections 4.1 through

4.10 of this Draft EIR. The project description and full discussion of impacts and mitigation measures can be found in Chapter 2, Project Description, and Chapter 4, Environmental Analysis, of this Draft EIR (Sections 4.1 through 4.10). As explained above, the impacts not included in Table ES-2 were determined to have “no impact” or a “less than significant impact” without the need for mitigation measures. Therefore, they were scoped out during the Notice of Preparation process and are listed in Section 6.4, Effects Found Not to Be Significant.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
Section 4.1, Air Quality
Threshold AQ-2:

Cumulative Increase in
Criteria Pollutant
Emissions (Construction)
Less than significant. No mitigation measures are required. Not applicable.

Threshold AQ-3: Sensitive
Receptors (Construction)
Less than significant. No mitigation measures are required. Not applicable.

Threshold AQ-4: Odors
(Construction)
Less than significant. No mitigation measures are required. Not applicable.

Section 4.2, Biological Resources
Threshold BIO-1:

Candidate, Sensitive, or
Special-Status Species
Potentially significant. BIO-1: Qualified Monitoring Biologist. Before the start of construction activities, the City of Anaheim project manager (or designee) shall retain a qualified monitoring biologist to implement required monitoring and document the names and resumes of the people involved in the biological monitoring of the project and a schedule for the proposed work.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
post-maintenance verification inspection. For highly sensitive resource areas, full-time biological monitors may be required. The Biological Construction Mitigation/Monitoring Exhibit shall be approved by the City of Anaheim project manager (or designee) before the start of construction. • Avian Protection. To avoid any direct impacts to raptors and/or any migratory birds protected under the Migratory Bird Treaty Act, removal of habitat that supports active nests on the proposed area of disturbance should occur outside the breeding season for these species (January 15 to August 31). If removal of habitat on the proposed area of disturbance must occur during the breeding season, the monitoring biologist shall conduct a pre-construction survey to determine the presence or absence of nesting birds on the proposed area of disturbance. The pre-construction survey must be conducted within 10 calendar days before the start of construction, the results of which must be submitted to the City of Anaheim project manager (or designee) for review and approval before initiating any construction activities. If nesting birds are detected, a letter report or mitigation plan as deemed appropriate by the City of Anaheim shall be prepared and include proposed measures to be implemented to ensure that disturbance of raptor and bird breeding activities are avoided. The report or mitigation plan shall be submitted to the City of Anaheim for review and approval and implemented to the satisfaction of the City of Anaheim. The monitoring biologist shall verify and approve that all measures identified in the report or mitigation plan are in place prior to and/or during construction.
• Resource Marking/Protection. Prior to the start of construction activities within the future site-specific proposed survey area, the qualified monitoring biologist shall supervise the placement of orange construction fencing or similar visible marker, staking, or flagging along the limits of the construction area, particularly where adjacent to sensitive biological avoidance areas, as shown on the Biological Construction Mitigation/Monitoring Exhibit to ensure crews remain within the approved construction limits. These demarcations shall not be required for areas with existing barriers, such as chain-link fencing, along the limits or facilities that are within and/or adjacent to developed and non-sensitive habitat areas.

This task shall include flagging plant specimens and delineating buffers to Chapter ES: Executive Summary
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OC River Walk Project
Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
protect sensitive biological resources (e.g., habitats, sensitive plant and wildlife species, including nesting birds) prior to construction. • Cover Trenches. The qualified monitoring biologist shall oversee the construction site so that cover and/or escape routes for wildlife from excavated areas shall be provided daily. Steep trenches, holes, and excavations during construction shall be covered at night with backfill, plywood, metal plates, or other means, and if plastic sheeting is used, the edges must be covered with soils such that small wildlife cannot access the excavated hole. Soil piles shall be covered at night to prevent wildlife from burrowing in. Sandbags shall weigh down the edges of the sheeting. These areas may also be fenced to prevent wildlife from gaining access. Exposed trenches, holes, and excavations shall be inspected twice daily (i.e., each morning and before sealing the exposed area) by the qualified monitoring biologist to monitor for wildlife entrapment. Excavations shall provide an earthen ramp to allow for a wildlife escape route. The qualified monitoring biologist shall verify that the contractor has covered all steep-walled trenches or excavations prior to the end of construction daily. If wildlife species are encountered within any trenches or excavated areas, the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape (e.g., a ramp or sloped surface at no greater than a 30-degree angle) and allow the species to disperse. In addition, the qualified monitoring biologist shall train construction personnel to increase awareness of the possible presence of wildlife beneath vehicles and equipment and to use best judgment to avoid killing or injuring wildlife (refer to Pre-Construction Meeting/Education).
• Structure Clearance. Before the issuance of any permit to allow for the removal or demolition of trees on the project site (particularly any ornamental trees in the developed land areas), the qualified monitoring biologist shall conduct clearance surveys to flush out any wildlife species nesting, roosting, or otherwise occupying the trees. If wildlife species are encountered within any of the trees (outside the general bird nesting season), the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape and allow the species to disperse. If Chapter ES: Executive Summary
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
tree-roosting bats are suspected, slow removal by gently pushing the tree over with heavy equipment is required.
• Pre-Construction Meeting/Education. Before the start of any construction activity where the site plan for the construction area indicates that significant impacts to biological resources may occur, a preconstruction meeting shall be held on site with the following in attendance:

City of Anaheim project manager (or designee), the construction contractor (if applicable), and the qualified monitoring biologist. At this meeting, the qualified monitoring biologist shall identify and discuss the construction protocols that apply to the proposed activities and the sensitive nature of the adjacent habitat with appropriate project personnel.

At the pre-construction meeting, the qualified monitoring biologist shall submit to the construction contractor a copy of the Biological Construction Mitigation/Monitoring Exhibit that identifies areas to be protected, fenced, and monitored. This data shall include all buffer limits, if applicable.

Before the start of construction activities, the qualified monitoring biologist shall meet with the construction contractor and crew and conduct an onsite educational session regarding the need to avoid impacts outside the approved construction footprint and to protect sensitive plants and wildlife that may occur at the specific facility. This may include but not be limited to explanations of the avian and aquatic resource buffers, the flag system for retention of sensitive plants, and clarification of acceptable access routes/methods and staging areas.
• Biological Monitoring and Reporting. The qualified monitoring biologist shall inspect/monitor the project construction area in accordance with the approved Biological Construction Mitigation/Monitoring Exhibit. This may be limited to pre- and post-maintenance inspections, weekly visits, or fulltime monitoring, as determined by the qualified monitoring biologist.

The qualified monitoring biologist shall document monitoring events via a Consultant Site Visit Record. This record shall be sent to the project manager each month. However, if weekly reports are submitted as part of a separate agency permit requirement, these reports may be forwarded to the project manager in place of Consultant Site Visit Record submittals.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
If no deviations from the construction site plan occur during maintenance, no additional documentation is required. However, if deviations from the site plan do occur, such as unanticipated impacts to sensitive vegetation communities or unanticipated discharge of pollutants, a Final Monitoring Report shall be prepared within 3 months following the completion of mitigation monitoring detailing maintenance and monitoring that occurred and any remedial or compensatory measures taken.

BIO-2: Sensitive Vegetation Communities and Jurisdictional Aquatic Resources Impacts Mitigation. Any direct impacts to sensitive vegetation communities or jurisdictional aquatic resources would require mitigation to comply with state and/or federal authorizations in accordance with the minimum ratios described in the following table and the ratios defined in any state and/or federal permit(s) issued for the project.

Mitigation Ratios for Potential Impacts to Sensitive Vegetation Communities and Jurisdictional Aquatic Resources
Vegetation Community Jurisdiction
Minimum Mitigation
Ratio
Fresh Water USACE/RWQCB/CDFW 2:1
Freshwater Emergent
Wetland
USACE/RWQCB/CDFW 2:1
Non-Vegetated Channel USACE/RWQCB/CDFW 2:1
Diegan Coastal Sage Scrub CDFW 2:1
Mule Fat Scrub (Disturbed) CDFW 2:1
Southern Willow Scrub USACE/RWQCB/CDFW 2:1
Notes: CDFW = California Department of Fish and Wildlife; RWQCB = Regional Water Quality Control Board; USACE = U.S. Army Corps of Engineers
• Potential direct impacts to sensitive vegetation communities, including jurisdictional aquatic resources, resulting from project implementation shall be mitigated through one of the following two options:
− Project compensatory mitigation for proposed impacts to sensitive vegetation communities, including jurisdictional aquatic resources, shall Chapter ES: Executive Summary
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
be provided through in-kind and on-site creation, enhancement, and/or restoration. A Habitat Mitigation and Monitoring Plan shall be provided and prepared in accordance with the City of Anaheim and regulatory agency requirements.
− Compensatory mitigation requirements that are not able to be satisfied through on-site creation, enhancement, and/or restoration shall be satisfied through the acquisition of mitigation bank credits via a resource agency-approved mitigation site within the Santa Ana River Watershed or by acquisition of other approved off-site mitigation credits. Prior to implementation of project construction impacts that would require compensatory mitigation, documentation demonstrating the availability of mitigation credits (i.e., credit ledger) at the approved mitigation site must be submitted to the City of Anaheim project manager (or designee) for confirmation.

When proposed mitigation involves habitat enhancement, restoration, or creation, the Habitat Mitigation and Monitoring Plan shall include the following information:
• Conceptual planting plan including planting zones, grading, and irrigation. • Seed mix/planting palette.
• Planting specifications.
• Monitoring program including success criteria.
• Long-term maintenance and preservation plan.

For mitigation that involves habitat acquisition, the Habitat Mitigation and Monitoring Plan shall include the following:
• Location of proposed acquisition.
• Description of the biological resources to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss. • Documentation that the mitigation area would be adequately preserved and maintained in perpetuity.

The identification of mitigation site credits shall be provided to the City of Anaheim project manager (or designee) and shall include the following:

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
• Location of approved mitigation site.
• Description of the mitigation credits to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss. • Documentation of the credits that are associated with a mitigation bank, which has been approved by the appropriate resource agencies. • Documentation in the form of a current mitigation credit ledger.

Habitat restoration and erosion control treatments shall be installed within these short-term impact areas. Habitat revegetation shall feature native species that are typical of the area, and associated erosion control best management practices shall include silt fence and microplastic- and weed-free straw fiber rolls, where appropriate. The revegetation areas shall be monitored and maintained for 25 months to ensure adequate establishment and sustainability of the plantings/seedings.

Where a project activity involves potential disturbance of non-native invasive plant species (as identified by the California Invasive Plant Council), these plants shall be entirely removed where feasible, and the removal shall be monitored by the qualified monitoring biologist to ensure that dispersal of propagules (e.g., seeds, stems, etc.) are avoided or minimized. Where removal of plant roots is not feasible (e.g., where erosive flows are predicted), aboveground plant material shall be fully removed and monitored by the qualified monitoring biologist. Where aboveground plant material cannot be removed (e.g., due to limited access), herbicides shall be applied by a licensed pest control advisor, using chemicals permitted as safe within aquatic environments.

BIO-4: Least Bell’s Vireo and Yellow Warbler Pre-Construction Surveys. For any work proposed in or near suitable habitat between February 15 and August 15 (March 15 and September 15 for least Bell’s vireo), a pre-construction survey for least Bell’s vireo and yellow warbler shall be performed to reaffirm the presence and extent of occupied habitat. The survey shall occur within five days prior to the start of construction. The pre-construction survey area for the species shall Chapter ES: Executive Summary
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
encompass all potentially suitable habitat within the project work zone and a 300-foot survey buffer. The pre construction survey shall be performed to the satisfaction of the City of Anaheim project manager (or their designee) by a qualified biologist familiar with the species. The results of the pre-construction survey shall be submitted in a report to the City of Anaheim project manager (or their designee) for review and approval before initiating any construction activities. If least Bell’s vireo or yellow warbler are detected, a minimum 300-foot buffer delineated by orange biological fencing shall be established around the detected species. In addition, on-site noise reduction/attenuation techniques shall be incorporated, as appropriate, to avoid impacts to breeding least Bell’s vireo and yellow warbler from elevated construction noise levels during the breeding season. The City of Anaheim project manager (or their designee) shall have the discretion to modify the buffer width depending on site-specific conditions. In addition, noise monitoring may be required to ensure that the elevated construction noise levels are appropriately attenuated at the edge of occupied habitat to a level that is not expected to adversely affect nesting bird behavior (i.e., not to exceed an hourly average of 60 A-weighted decibels or ambient whichever is greater, at the edge of occupied habitat).

Threshold BIO-2: Riparian
Habitat and Other
Sensitive Natural
Communities
Potentially significant. BIO-1, BIO-2, and BIO-3, Less than significant.

Threshold BIO-3:

Wetlands
Potentially significant. BIO-1, BIO-2, and BIO-3, Less than significant.

Threshold BIO-4: Native
Resident or Migratory Fish
or Wildlife Species
Less than significant. No mitigation measures are required. Not applicable.

Section 4.3, Cultural Resources
Threshold CUL-1:

Historical Resources
No impact. No mitigation measures are required. Not applicable.

Threshold CUL-2:

Archaeological Resources
Less than significant. No mitigation measures are required. Not applicable.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
Section 4.4, Geology and Soils
Threshold GEO-1.i:

Exposure to SeismicRelated Hazards -
Rupture of a Known
Earthquake Fault
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-1.ii:

Exposure to SeismicRelated Hazards –
Ground Shaking
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-1.iii:

Exposure to SeismicRelated Hazards -
Liquefaction
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-1.iv:

Exposure to SeismicRelated Hazards -
Landslide
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-2: Soil
Erosion or Topsoil Loss
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-3:

Geologic Stability
Less than significant. No mitigation measures are required. Not applicable.

Threshold GEO-4:

Expansive Soils
Less than significant. No mitigation measures are required. Not applicable.

Section 4.5, Greenhouse Gas Emissions
Threshold GHG-1:

Generation of Greenhouse
Gas Emissions
(Construction)
Less than significant. No mitigation measures are required. Not applicable.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
Section 4.6, Hazards and Hazardous Materials
Threshold HAZ-2:

Accidental Releases
Less than significant. No mitigation measures are required. Not applicable.

Threshold HAZ-4:

Hazardous Materials Sites
Less than significant. No mitigation measures are required. Not applicable.

Section 4.7, Hydrology and Water Quality
Thresholds HYD-1 and
HYD-3c (polluted runoff):

Water Quality Standards
and Polluted Runoff
Potentially significant. HYD-1: Prior to the issuance of a discretionary and/or regulatory permit by the City of Orange, County of Orange, or Orange County Water District (“Participating Stakeholders”), the City of Anaheim shall enter into a Maintenance and Operations Agreement (MOA) with the Participating Stakeholder issuing said permit, as applicable. The MOA shall specify roles, responsibilities, performance standards, and communication protocols for the ongoing maintenance and operation of the project elements.

The MOA shall include, at a minimum, the following responsibilities and tasks, or similar, as appropriate for each agreement with the applicable agency:
• Maintenance responsibilities related to trails, river impoundments and water features, and stormwater and sewer facilities;
• Operations responsibilities related to access control, hours of operation, public use rules (including, but not limited to, posting signage for hours, allowed uses, and prohibited activities), security and public safety (including, but not limited to, law enforcement coordination, patrolling duties, transient management, and emergency response protocols), debris removal, preparation and implementation of a flood contingency plan, and post storm event procedures;
• Inspection, monitoring, and reporting responsibilities, including the frequency of routine inspections and water quality monitoring as required by applicable regulatory permits and to address any public health concerns regarding recreational use of the water in the Santa Ana River channel; and • Communication and notification protocols, including construction timing and phasing information for each project element.

The MOA shall include provisions granting the County of Orange (OC) agencies—including, but not limited to, OC Public Works, OC Parks, and OC Less than significant.

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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
Sheriff’s Department—vehicular access for monitoring river flows, ensuring public safety, and performing other OC maintenance and operational activities currently conducted by OC agencies, including review and approval of trail improvements and access design. The MOA shall also address any other items deemed necessary by the Participating Stakeholders to ensure the proper longterm maintenance and operation of the project.

Threshold HYD-3a: Site
Drainage and Hydrology
(Erosion and Siltation)
Less than significant. No mitigation measures are required. Not applicable.

Thresholds HYD-3b and
3d: Site Drainage and
Hydrology (Flooding and
Flood Flows)
Less than significant. No mitigation measures are required. Not applicable.

Threshold HYD-3c: Site
Drainage and Hydrology
(Drainage Capacity)
Less than significant. No mitigation measures are required. Not applicable.

Threshold HYD-4: Flood
Hazard or Seiche
Less than significant. No mitigation measures are required. Not applicable.

Threshold HYD-5: Water
Quality Control Plan
Less than significant. No mitigation measures are required. Not applicable.

Section 4.8, Noise
Threshold N-1:

Exceedance of Noise
Standards
Potentially significant NOI-1: The City of Anaheim shall include the following construction specifications on all project construction plans for sites located within 100 feet of sensitive receptors (i.e., Extended Stay America – Orange County hotel building and occupied residential buildings) or 60 feet of occupied office buildings.

During construction, the construction contractor shall employ the following noise-reducing measures where use of construction equipment occurs within 100 feet of sensitive receptors or 60 feet of occupied office buildings:
• Use acoustical shelters around any air compressors, generators, and any other stationary construction equipment not fitted with baffled enclosures • Use baffling around stationary construction equipment to reduce noise and vibration levels
Less than significant
Chapter ES: Executive Summary
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
• Properly muffle and maintain all construction equipment powered by internal combustion engines
• Prohibit unnecessary idling of internal combustion engines • Whenever feasible, use electrical power to run air compressors and similar power tools
Threshold N-2: Excessive
Groundborne Vibration or
Noise
Potentially significant NOI-2: The City of Anaheim shall ensure that all project construction specifications include the following noticing requirement. The construction contractor shall provide written notification at least 1 week prior to the start of any construction activities within 110 feet of sensitive receptors (i.e., Extended Stay America – Orange County hotel and occupied residential buildings) or 235 feet of the Kinder Morgan Orange Terminal. The notice shall inform hotel, occupied residential buildings, and industrial operators of the estimated start date and duration of daytime vibration-generating construction activities and provide a point of contact for vibration exposure complaints.

Less than significant
Section 4.9, Transportation
Threshold T-2: Induction
of Substantial Vehicle
Miles Traveled
Less than significant. No mitigation measures are required. Not applicable.

Section 4.10, Tribal Cultural Resources
Threshold TCR-1: Tribal
Cultural Resources
Potentially significant TCR-1: Prior to the commencement of ground-disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below. If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on-site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

A. The Native American Monitor shall be from the Gabrieleño Band of Mission Indians – Kizh Nation (Kizh) or Juaneño Band of Mission Indians, Acjachemen Nation – Belardes (Acjachemen). The lead Native American Less than significant
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
Monitor shall serve as the point of contact and coordinator for the project during monitoring activities.

B. For the purposes of this requirement, “ground-disturbing activity” includes project locations inside the project boundary, excluding off-site work within existing public right-of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring agreement with the lead Native American Monitor Tribe prior to the earlier of the commencement of any ground-disturbing activity, or the issuance of any permit necessary to commence a ground-disturbing activity.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground-disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency.

Monitor logs shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods.

Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground-disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance Chapter ES: Executive Summary
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Table ES-2. Summary of Environmental Impacts and Mitigation Measures Impact
Level of Significance
Before Mitigation Mitigation Measure
Level of
Significance After
Mitigation
activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or 2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

F. Upon discovery of any Tribal Cultural Resources, all construction activities in the immediate vicinity of the discovery shall cease (i.e., not less than the surrounding 50 feet) and shall not resume until the discovered Tribal Cultural Resource has been fully assessed by Kizh and Acjachemen monitors and an archaeologist retained by the lead agency. The Kizh or Acjachemen Tribe shall recover and retain all discovered Tribal Cultural Resources in the form and manner the affected Tribe deems appropriate, in the affected Tribe’s sole discretion, and for any purpose the affected Tribe deems appropriate, including for educational, cultural and historical purposes.

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ES.6 Alternatives to the Proposed Project
Section 15126.6(d) of the CEQA Guidelines requires an EIR to provide sufficient information about each alternative to allow for meaningful evaluation, analysis, and comparison with the project. The City of Anaheim selected the alternatives to adequately represent the range of feasible alternatives required under CEQA for the project. The No Project/No Improvements Alternative is included, as required by CEQA Guidelines, Section 15126.6(e), even though it would not meet the basic project objectives. Alternative 2 is a reduced scope option that could potentially meet some of the lead agency’s objectives. Below is a description of the two alternatives and a summary of the impact analyses:
• Alternative 1: No Project/No Improvements Alternative. Under the No Project Alternative, none of the Group A, B, C, or D improvements would occur.

The No Project/No Improvement Alternative would avoid some of the short-term construction related impacts. Because no changes would occur under the No Project/No Improvement Alternative, less than significant impacts potentially resulting from the project for the following environmental topics would be avoided: aesthetics, air quality, biological resources, cultural resources, geology and soils, hazards and hazardous materials, and tribal cultural resources. However, as discussed above, the long-term VMT, air quality, and GHG impacts would be greater under the No Project/No Improvement Alternative. Additionally, this alternative would not attain any of the objectives established for the project, including environmental benefits related to trail improvements, groundwater recharge, and open space restoration. Additional benefits of the project, such as enhanced community access, recreational opportunities, wildlife and habitat benefits, and infrastructure improvements would not occur. • Alternative 2: Group A and C Impoundments and Trails Alternative. Under the Group A and C Impoundments and Trails Alternative, the Group B – New Pedestrian/Bike Bridges and Group D – Enhanced Community Recreation Amenities would not occur.

The Group A and C Impoundments and Trails Alternative would reduce some of the shortterm construction related impacts. Because no bridges would occur under the Alternative 2, less than significant impacts resulting from the project for construction noise would be reduced. Under this alternative, some of the park and open space improvements with potential habitat restoration would not occur, which would have a beneficial impact on the biological habitat after construction. However, as discussed above, the long-term VMT, air quality, and GHG impacts would be slightly greater under Alternative 2.

The Group A and C Impoundments and Trails Alternative achieve some of the objectives identified above in Section ES.3, Project Objectives, including environmental benefits related to trail improvements in groundwater recharge. However, without the bridges, Chapter ES: Executive Summary
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some of the VMT reduction benefits would not occur to the same extent as the full project. This alternative would only partially meet the project objectives and only partially achieve the associated benefits.

Detailed descriptions and an analysis of potential impacts of each alternative are presented in Chapter 5, Alternatives. The environmentally superior alternative would be the Alternative 2:

Group A and C Impoundments and Trails Alternative, because it would result in the greatest reduction in environmental impacts compared to the project. CEQA Guidelines Section 15126.6(e)(2) requires identification of an environmentally superior alternative; however, this designation does not imply that implementing the alternative is superior to implementing the full project. The lead agency must also consider other factors—such as the ability to meet project objectives—before making a final decision.

ES.7 Potential Areas of Controversy and Issues to Be Resolved There are no areas of controversy known to the lead agency related to physical environmental impacts of the project, including issues raised by agencies and the public. All environmental topic areas have been reduced to a less than significant with or without mitigation, and no significant and unavoidable impacts remain. However, it should be noted that operations and maintenance agreements must be in place with agencies that define responsibilities for operation and maintenance.

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Chapter 1: Introduction
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Chapter 1 Introduction
The City of Anaheim has prepared this Environmental Impact Report (EIR) to inform the public, local community, organizations, responsible agencies, trustee agencies, and other interested public agencies about potential significant environmental effects resulting from implementation of OC River Walk Project (project) and possible measures to mitigate those significant effects and alternatives to the project. This EIR was prepared in compliance with the California Environmental Quality Act (CEQA) (California Public Resources Code, Section 21000 et seq.), CEQA Guidelines (CEQA Guidelines, Section 15000 et seq.), and the City of Anaheim’s procedures for implementing CEQA. This EIR is a “Project EIR” pursuant to CEQA Guidelines, Section 15161. A Project EIR examines the environmental impacts of a specific project. This EIR focuses on the environmental effects particular to the project as contemplated by the CEQA Guidelines.

1.1 Project Overview
The OC River Walk Conceptual Master Plan consists of various multi-purpose improvements that have been identified to transform the Santa Ana River corridor and portions of the existing Santa Ana River Trail (SART) into an iconic location and experience in of itself (project). The project will take place within and adjacent to the Santa Ana River. Specifically, the project site is located along the Santa Ana River corridor, generally extending from Orangewood Avenue north to Ball Road and the existing Anaheim Coves at Burris Basin, encompassing approximately 111 acres. The main components of the OC River Walk Conceptual Master Plan involve creating two water impoundments by installing three inflatable rubber dams, modifying the riverbanks, constructing two pedestrian/bike bridges, providing new trails, improving existing trails, creating new and protection of existing access ramps, constructing two new undercrossings on the west bank at the UPRR and the Metrolink railroad (LOSSAN Corridor), and providing enhanced community recreation amenities (e.g., terraced seating, nature play areas, parklets, plazas, gathering areas for large-scale events, festivals, and other activities, water access, kayak launch, etc.).

1.2 Project Background
The Santa Ana River corridor offers a potential network of trails and recreation open space for the public, including the currently available SART. The OC River Walk Engineering Feasibility Study (Feasibility Study), completed in 2021, identified 17 design opportunities to expand the Santa Ana River Corridor public access and recreational amenities. The design opportunities identified included developments related to pedestrian/bike facilities, community amenities such as upland habitat restoration and cantilever decks, and river activation systems such as impoundment structures and river recreation. The opportunities outlined in the study align with the U.S. Army Corps of Engineers (USACE) Operating Principles, as well as the Coastal Conservancy's Santa Ana River Conservancy Program Goals. The project consists of several multi-purpose Chapter 1: Introduction
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improvements that are consistent with the Feasibility Study’s design opportunities.

Implementation of the project would further Coastal Conservancy’s Santa Ana River Conservancy Program Goals to protect and preserve water resources; preserve and enhance wildlife and habitat; and provide equitable education and recreation access.

1.3 Purpose and Use of the Environmental Impact Report
The City of Anaheim has prepared this EIR for the following purposes:
• To satisfy the requirements of CEQA, pursuant to California Public Resources Code, Section 21080
• To inform the public, local community, organizations, and responsible, trustee, and other interested public agencies of the nature of the project, its potentially significant environmental effects, its potentially feasible measures to mitigate those impacts, and the reasonable potentially feasible alternatives to the project • For consideration by responsible agencies in issuing permits and approvals for the development that would occur from the implementation of the project CEQA and the CEQA Guidelines require the decision-making agency to balance, as applicable, the economic, social, technological, legal, or other benefits of a project against its unavoidable environmental risks when determining whether to approve a project. As noted previously, this EIR is an informational document, the purpose of which is to identify the potentially significant effects of the project on the environment and to indicate the manner in which those significant effects can be avoided or reduced to a less than significant level, to identify any significant and unavoidable adverse impacts that cannot be mitigated to below a level of significance, and to identify reasonable and potentially feasible alternatives to the project that would avoid or substantially lessen any significant, adverse environmental effects associated with the project.

The CEQA lead agency (i.e., City of Anaheim) is required to consider the information in this EIR and any other relevant information in the administrative record in making its decision on the project. This EIR does not determine the ultimate decision that will be made regarding the project.

Nevertheless, CEQA requires the City of Anaheim to consider the information in this EIR before approving the project and to make Findings of Fact regarding each significant effect identified in this EIR.

This EIR will be circulated to responsible and trustee agencies with jurisdiction over resources affected by the project, including local, state, and federal agencies, and interested parties and individuals. In reviewing this EIR, reviewers should focus on the sufficiency of the document in identifying and analyzing potentially significant effects on the environment and avoiding or mitigating the significant effects of the project.

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This EIR will be used by the City of Anaheim to evaluate the environmental implications of adopting the project. If certified, this EIR will be relied upon by agencies with permitting or approval authority over the project.

1.4 Lead, Responsible, and Trustee Agencies

1.4.1 Lead Agency
In accordance with CEQA Guidelines, Sections 15050 through 15053 and 15367, the City of Anaheim is the designated lead agency, which is defined as the “public agency which has the principal responsibility for carrying out or approving a project.” The lead agency is also responsible for determining the scope of the environmental analysis, preparing the EIR, and responding to comments received on the Draft EIR. Before making a decision to approve a project, the lead agency is required to certify that the EIR has been completed in compliance with CEQA, the decision-making body has reviewed and considered the information in the EIR, and the EIR reflects the independent judgment of the lead agency.

1.4.2 Responsible and Trustee Agencies
Responsible agencies are state and local public agencies, other than the lead agency, that have some authority to carry out or approve a project or that are required to approve a portion of a project or a permit for which a lead agency is preparing or has prepared an EIR or Negative Declaration (CEQA Guidelines, Section 15381). Trustee agencies are designated public agencies with legal jurisdiction over natural resources that are held in trust for the people of California and that would be affected by a project, whether or not the agencies have authority to approve or implement the project (CEQA Guidelines, Section 15386). The following agencies would potentially act as responsible and/or trustee agencies for the purposes of the project:
• U.S. Fish and Wildlife Service (USFWS). The project involves approval of Sections 7 and 10(a) of the Endangered Species Act compliance. Section 7 ensures that federal agencies, in carrying out their programs, utilize their authorities to conserve endangered and threatened species and prevent their actions from jeopardizing listed species or destroying or adversely modifying their critical habitat. It applies to actions that federal agencies fund, authorize, or carry out, where there is discretionary federal involvement or control, and it requires the applicant to submit a permit application to the USFWS.

Section 10(a) of the Endangered Species Act allows for incidental take permits for activities that might otherwise be illegal, provided a HCP is in place. • U.S. Army Corps of Engineers (USACE). Approval of Section 404 Permit, Section 408 Permit. Section 404 establishes a permit program administered by the USACE that regulates the discharge of dredged or fill material into waters of the United States, including wetlands. Section 408 program allows the City of Anaheim to alter a UCACE civil works project. The Santa Ana River is UCACE’s civil works project.

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• California Department of Fish and Wildlife (CDFW). The project site includes the Santa Ana River and surrounding area, which is valuable habitat for biological resources. The project would be subject to review by CDFW for activities that may impact biological resources.

The CDFW would also provide biological expertise to review and comment on the CEQA documents prepared. The project could alter streambeds and/or riparian habitats and would require approval of a California Fish and Game Code Section 1602 permit which requires that for such projects, any entity, including any state or local governmental agency, provide written notification to the CDFW before beginning any construction project. • California Department of Transportation (Caltrans). The Project site is within the California Department of Transportation (Caltrans) facilities, including State Route 57.

Caltrans’ approval would be required for any encroachments or construction of facilities in a Caltrans right-of-way associated with the project’s conditions of approval. • State Historic Preservation Office (SHPO). For projects with federal funding or requiring federal approvals, Section 106 of the National Historic Preservation Act of 1966, as amended by U.S. Code, Title 16, Section 470 et seq., and the Code of Federal Regulations, Title 36, Section 800, includes provisions for protection of significant archaeological and historical resources. The SHPO is the administering agency of Section 106 compliance. The project is federally funded and would be subject to approval with Section 106.
• California Public Utilities Commission (CPUC). CPUC regulates the construction, alteration, and maintenance of railroad crossings, including undercrossings. The CPUC has jurisdiction over the design, construction, alteration, and maintenance of rail crossings (both at-grade and grade-separated), therefore, approval of railroad undercrossings at UPRR north of Katella and at Metrolink/LOSSAN adjacent to ARTIC will be required. • California Department of Water Resources (DWR). DWR provides oversight, support, and evaluation of Groundwater Sustainability Agencies and Groundwater Sustainability Plans under the Sustainable Groundwater Management Act. DWR will provide review and oversight support on groundwater issues if not covered by OCWD. • California State Water Board, Division of Drinking Water (DDW). DDW is responsible for regulating potable water use under Title 22 of the California Code of Regulations.

DDW reviews the engineering report for GWRS water and issues permits related to potable reuse. The project will require approval of a Title 22 Reuse Permit Amendment for GWRS water to ensure public health protection.
• Santa Ana Regional Water Quality Control Board (RWQCB). The Santa Ana Regional Water Quality Control Board regulates water quality through the federal Clean Water Act Section 401 Certification process and oversees the National Pollutant Discharge Elimination System Permit No. CAS612008. The RWQCB is responsible for implementing permitting, compliance, and other activities to reduce pollutants in Chapter 1: Introduction
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municipal, construction, and industrial stormwater runoff, including overseeing the development and implementation of Water Quality Improvement Plans as required by the Regional Municipal Separate Storm Sewer System Permit for the Santa Ana region, which includes the City, as well as ensuring that all other Municipal Separate Storm Sewer System Permit requirements are met. Regional Water Quality Control Board’s Division of Drinking Water oversees the use of recycled water in the State of California by issuing waste discharge permits to ensure compliance with water quality standards and environmental regulations. The OCWD GWRS Waste Discharge Requirements and Master Recycling Permit will be amended to include the impoundments within the Santa Ana River for groundwater recharge and potential recreational activities within the SAR. • Southern California Regional Rail Authority (SCRRA). The SCRRA operates Metrolink, a commuter rail system in the Southern California region. The project site intersects with Metrolink rail lines. SCRRA approval would be required for encroachment related to Metrolink facilities associated with the project.
• City of Orange. The City of Orange is the local permitting agency for incorporated portions of Orange, California. Portions of the project site are within the City of Orange. The City of Orange’s approval would be required for any encroachments or access associated with the Project.
• Orange County Flood Control District (OCFCD). The OCFCD is responsible for regional and local drainage and flood control facilities throughout the County. The project site would involve connections to OCFCD drainage and flood control facilities. OCFCD approval would be required for any encroachments, construction, or use of facilities associated with the project.
• Orange County Public Works (OCPW). The OCPW is responsible for the approval of construction and general use permits for projects within Orange County. Projects are required to obtain permits prior to the start of construction. OCPW’s approval would be required for construction activities associated with the project. • Orange County Parks. Orange County Parks is responsible for the maintenance and operation of Orange County’s parkland, open space, and shorelines. Portions of the SART that are within Orange County Parks’ jurisdiction are also within the project site.

Orange County Parks’ approval would be required for any use of facilities associated with the project.
• Orange County Water District (OCWD). OCWD is a groundwater wholesaler agency responsible for management and protection of the Orange County Groundwater Basin. The project involves the creation of river impoundments that would result in additional groundwater recharge in the Orange County Groundwater Basin. OCWD’s review and approval would be required to ensure that the project would not impact groundwater quality as well as consent to own and operate the inflatable dams.

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• Orange County Sanitation District (OCSAN). The OCSAN is responsible for sewer facilities operation and maintenance throughout Orange County. The project includes on and offsite sewer improvements. OCSAN’s approval would be required for encroachment or use of OCSAN facilities associated with the project. • Orange County Transportation Authority (OCTA). OCTA is the public transportation provider for Orange County and is responsible for public bus and train services. Rail lines operated by OCTA, including Metrolink and Los Angeles-San Diego-San Luis Obispo Rail Corridor, intersect the project site. OCTA’s approval would be required for encroachment and access of OCTA rail lines associated with the project, including those located on the project site.

1.5 Environmental Impact Report Review Process

1.5.1 Notice of Preparation
In accordance with CEQA Guidelines, Section 15082, a Notice of Preparation (NOP) was circulated for public and public agency reviews from March 23, 2023, through April 24, 2023 (included as Appendix A). The purpose of the NOP is to provide notification that an EIR for the project is being prepared and to solicit guidance on the scope and content of the document.

Pursuant to CEQA Guidelines, Section 15082, the lead agency held a public scoping meeting on March 29, 2023. Public agencies and members of the public were invited to attend and provide input on the scope of this EIR. Comments from the public and public agencies in response to the NOP are provided in Appendix B and summarized in Table 1-1, NOP Comment Summary.

Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
City of Orange No comment. N/A
City of Irvine No comment. N/A
City of Fullerton No comment. N/A
Orange County Water
District (OCWD)
• Include discussion of conveyance facilities.
• Include discussion of groundwater
replenishment system (GWRS) water in Santa
Ana River.

Description of the OCWD GWRS turnout
structure is included in Section 2.3.1,
Orange County Water District
Groundwater Replenishment System
Turnout Structure.
• Include an assessment of GWRS water quality
compatibility with the project area/features
needs.
• How will the project seek to control/eliminate
algae growth?
• Any potential chemical addition, polishing
treatment, or other modifications to GWRS
water quality will need to be addressed.

Refer to Section 4.7, Hydrology and
Water Quality. Specifically, refer to
Section 4.7.4.6, Threshold HYD-5: Water
Quality Control Plan.

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Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• Will the project create new wildlife habitat and
any associated new obligations for Anaheim
and/or OCWD?
The project will not create permanent
new wildlife habitat, as the
impoundments will be periodically
emptied with the deflation of the rubber
dams. Improvements to the river
corridor’s ecology will result from cleaner
water and landscaping along the river
corridor. The project would not impose
new obligations on Anaheim and/or
OCWD.

Orange County Public
Works (OCPW)
OC Flood Program/Floodplain Management –
Engineering
• Hydrology and Hydraulics – design standards
will meet USACE and OCFCD criteria, including
levee design, vegetation, freeboard, etc. The
Channel is designed to function and
accommodate flows as part of the Santa Ana
River Mainstem (SARM) system that includes
Prado Dam, Prado Basin, Seven Oaks Dam and
various dike features.

The project would be designed to meet
design standards of USACE and Orange
County Flood Control District (OCFCD)
through the 408 permitting process. See
Section 2.4, Project Components, and
Appendix G, Hydrology and Hydraulics,
Chapter 6.
• Impoundment of water must demonstrate no
impact to local drainage and/or interior drainage
to the surrounding areas during any storm
events. Explain and address any effects of the
impoundment on the Collins Channel (OCFCD
Facility No. E07). This channel contains
deficient segments that may require future
improvements. The potential development
should not worsen the existing conditions or
shift flooding deficiencies to this channel.

Similarly, please explain how these
improvements would impact the Chantilly Storm
Channel (OCFCD Facility No. E01S02). Further
discussions are also needed for the proposed
structures for urban storm water treatment and
their effects on the functions of these flood
control facilities.

Refer to Section 4.7, Hydrology and
Water Quality, and Appendix G,
Hydrology and Hydraulics.
• Structural and Bridges – design standards will
meet USACE and OCFCD criteria, including
freeboard, scour, debris, etc. Improvements and
structures will need to withstand the velocity of
the water from Prado Dam releases.

Refer to Section 2.4, Project
Components, and Appendix G,
Hydrology and Hydraulics, Chapter 2.

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Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
Construction:
• Project will require OCFCD Encroachment,
Section 408 and 404 Permits. Prior to OCFCD’s
participation in the Section 408 Permit process,
the cities of Anaheim and Orange are required
to enter into a cooperative agreement with
OCFCD and OC Parks for the OC River Walk
Project, which will be approved and executed by
an authorized representative of the County of
Orange Board of Supervisors.

Refer to Section 2.5.1, Other Agency
Approvals, and Appendix G, Hydrology
and Hydraulics, Chapter 3.
• Temporary Construction Easements needs to
be identified and secured for the duration of the
project.

Various stakeholders for the temporary
construction easements are listed in
Section 2.5.1, Other Agency Approvals.
• A flood contingency plan will be required for
review and approval by OCFCD and USACE.

Review and approval of a flood
contingency plan are listed under
UCACE and OCFCD in Section 2.5.1,
Other Agency Approvals.

Public Services Impacts
• The project has features proposed within areas
of the Channel that are owned by OCFCD and
that are outside of public right-of-way. These
areas are currently not publicly accessible due
to concerns for safety, hazard prevention and
public health. The Initial Study should mention
that the public is not authorized to be on the
Channel’s grouted riprap currently, as it would
be considered trespassing and hazardous.

Refer to Section 2.1.2, Existing Land
Uses. It states that the public is currently
not authorized to be within the Santa Ana
River channel or on the channel’s
grouted riprap embankments.
• The Initial Study also did not acknowledge the
need to analyze the project impacts on public
services. Due to the project increasing
accessibility to the public on the Channel, it is
appropriate for the EIR to analyze an increased
reliance on local police and reflect that the
respective cities’ police forces will mitigate such
impacts by perhaps increasing personnel,
increasing patrols, improving lighting, taking
efforts to prevent overnight encampments,
perform debris and graffiti removal.

Refer to Section 6.4, Effects Found Not
to Be Significant. Also, the City of
Anaheim would be required to enter into
a separate Maintenance and Operations
Agreement with the City of Orange,
County of Orange, and Orange County
Water District for the long-term
maintenance and operation of the
project. See Mitigation Measure HYD-1.
• Similarly due to the project increasing
accessibility to the public on the Channel, it is
appropriate for the EIR to analyze impacts to
performance of flood control and protection
activities. The existing Channel is currently
eligible for Public Law 84-99 program coverage.

When flood conditions exceed, or are predicted
to exceed, the response capability of levee and
drainage districts and local or state governments,
the USACE has the authority under Public Law
84-99 to provide emergency flood response
Refer to Section 2.4, Project
Components. The project would not
affect the eligibility status under PL 84-

99. Chapter 1: Introduction
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Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
assistance without further specific authorization
of Congress. The USACE can furnish assistance
for flood emergency preparation, flood fighting,
and the repair and restoration of certain flood
damage reduction projects damaged or
destroyed by flood. Assistance also includes
providing flood fighting personnel for technical
advice, sandbags, plastic sheeting, pumps, or
other materials and equipment for an imminent or
actual flood emergency to protect against
substantial loss of life and property. The City will
need to ensure that the project will not change
the Channel’s Public Law 84-99 eligibility status
and ensure that the City will be responsible for
any flood control feature replacements not
covered by PL 84-99.

Right-of-Way:
• Permittee is required to identify ROW needed for
the project construction phase and post
construction, if any. The City will need to offer to
purchase from OCFCD ROW necessary for the
project based upon a market appraisal, and
acquire said rights, interest or authorizations to use
of OCFCD land and/or facilities prior to
commencing work for the project on OCFCD land
and/or facilities. Any ROW interest or use
agreement with include terms for the City to be
fully responsible for any increased fiscal
obligations incurred by OCFCD or the County and
shall include indemnification and hold harmless
terms for City to assume all liability and risk
associated with the project. Each ROW document
and agreement will include terms stating that the
primary function of the Channel is flood control for
SARM system that serves other counties
upstream. As it may be found inappropriate for the
project to hinder receipt of water flows in a storm
event, impacting communities all along the
Channel, the EIR will need to show it is not
offending basic water rights.

Appropriate rights-of-way will be
identified for the construction phase of
the project prior to the initiation of each
project element. Section 2.5.1, Other
Agency Approvals, lists the agencies and
discretionary actions anticipated for the
project. Additionally, this comment does
not pertain to the physical environmental
effects of the project. The City of Orange
is actively negotiating with the County of
Orange for a long-term easement
agreement.
• Any proposed bridges for the project may
require new bridge and highway easement(s)
and/or other ROW agreement that the City
would be responsible for the operation and
maintenance of said bridge, including pier noses
and footings, and that City will be responsible
for any damages to flood features caused by the
structure’s presence in the Channel.

The City acknowledges the comment and
will acquire the easement(s) necessary
to implement the project. The City would
also be responsible for maintenance and
operation, as specified in the future
maintenance and operations
agreement(s) (refer to Mitigation
Measure HYD-1 in Section 4.7,
Hydrology and Water Quality).

Chapter 1: Introduction
Final EIR No. 357 1-10 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
Operations & Maintenance:
• The Santa Ana River’s primary function is flood
control; therefore, the permittee will be required
to operate and maintain all functions of the OC
River Walk components, including but not
limited to, any levee bank
modifications/benches, vegetation, trails,
bridges, water impoundment features, lighting,
access to and from trails, fencing, gates, etc.

The City concurs with the comment.
• Permittee is required to enter into a cooperative
agreement with OCFCD and OC Parks and/or a
Lease Agreement with OCFCD for the use of
OC River Walk.

The City acknowledges the comment and
will enter into a cooperative and/or lease
agreements with appropriate agencies.

Section 2.5.1, Other Agency Approvals,
lists the agencies and discretionary
actions anticipated for the project.

Additionally, the City of Orange is actively
negotiating with the County of Orange for
a long-term easement agreement.
• A flood contingency plan may be required to
address water impoundment and unexpected
release(s) from Prado Dam.

The need for a flood contingency plan
would be determined as part of the future
maintenance and operations agreement.

Environmental:
• What are the environmental and hydrological
impacts of multiple impoundments operating at
same time?
Refer to Section 4.7, Hydrology and
Water Quality.
• Any and all resource agency or regulatory
permits, agreements, or other instruments which
may impact OCFCD must be approved prior by
the Director of OC Public Works. City shall
obtain reasonable and appropriate regulatory
advance guidance on approved “safe harbor”
performance allowable for all stages of the
project and when applicable, make earnest
effort to facilitate agreements with specific
regulatory agencies, such as a Lake or
Streambed Alteration Agreement or California
Endangered Species Act Incidental Take
Permit, to safeguard District regarding liability
issues for Channel operation and maintenance
impacted by the project.

Section 2.5.1, Other Agency Approvals,
lists the agencies and discretionary actions
anticipated for the project, which includes
regulatory permits from the U.S. Fish and
Wildlife Service, U.S. Army Corps of
Engineers, California Department of Fish
and Wildlife, to safeguard the OCFCD
regarding liability issues for the Santa Ana
River channel operation and maintenance
impacted by the project. Furthermore, the
City of Anaheim would be required to enter
into a separate Maintenance and
Operations Agreement with the City of
Orange, County of Orange, and Orange
County Water District for the long-term
maintenance and operation of the project.

See Mitigation Measure HYD-1, Section

4.7, Hydrology and Water Quality.

Chapter 1: Introduction
Final EIR No. 357 1-11 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• Address any public health concerns regarding
recreational use of the water in the Channel;
include water quality and post-storm event
procedures in an Operation and Maintenance
Manual provided to OCFCD via encroachment
permit for review and approval.

The City of Anaheim would be required
to enter into a separate Maintenance and
Operations Agreement with the City of
Orange, County of Orange, and Orange
County Water District for the long-term
maintenance and operation of the
project. See Mitigation Measure HYD-1,
Section 4.7, Hydrology and Water
Quality.
• An assessment should be carried out to identify
specific opportunities that can be incorporated
into the project to benefit wildlife and specifically
wildlife that relies upon riverine and riparian
conditions. For example, there are opportunities
to: (1) include vegetated bioengineered
solutions on the riverbank to encourage native
vegetation rather than just reinforcing the slopes
with hard engineering solutions, (2) provide
better connectivity to adjacent basins to improve
habitat for wildlife, (3) establish better quality in
channel habitats at the upper limits of the
proposed impoundments, as the water becomes
shallow, potentially with a reduced need to
entrain the river for recharge if greater recharge
is occurring in the basins. The assessment
should consider these and other habitat and
environmental improvement opportunities. The
LA River Master Plan is a good reference for
identifying and incorporating multifunctional
benefits into a development such as this.

The project is required to be designed to
comply with the USACE’s Guidelines for
Landscape Planting and Vegetation
Management at Levees, Floodwalls,
Embankment Dams, and Appurtenant
Structure (ELT 1110-2-583). Section 4,
Design Considerations. Suitable
vegetation will be determined through the
408 permitting processes. While there
are opportunities to include vegetated
bioengineered solutions on the riverbank
to encourage native vegetation, the
project is required to adhere to the
options outlined in the USACE document
such as the use of planter boxes.

River Bank Modifications
• There is a significant opportunity for this project
to enhance the biological diversity of the river
and especially the river banks in a manner that
is conducive with the wider aims of the project.

Section 1.4.1.2 only discusses hard engineering
solutions for bank modifications. There is an
opportunity to utilize both hard engineering
solutions and soft bio-engineering solutions to
create attractive riparian vegetated areas,
provide habitat for wildlife and can help with
water quality treatment.

The project would be designed in
compliance with the USACE’s Guidelines
for Landscape Planting and Vegetation
Management at Levees, Floodwalls,
Embankment Dams, and Appurtenant
Structure (ELT 1110-2-583), Section 4,
Design Considerations, which would be
reviewed and approved through the 408
permitting processes.

Urban Stormwater Treatment
• Information on the urban stormwater treatment
is vague. Is this in reference to an Irvine Ranch
Water District San Joaquin Marsh style natural
water treatment system? There is also the
opportunity to utilize low impact development
(LID) techniques to treat storm and dry weather
runoff along and adjacent to the trail. There is
Refer to Section 4.7, Hydrology and
Water Quality. The project would be
designed to comply with the North
Orange County TGD and Model WQMP
to achieve MS4 permit compliance.

Furthermore, the project would be
designed in compliance with the
USACE’s Guidelines for Landscape
Chapter 1: Introduction
Final EIR No. 357 1-12 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
also the potential to allow more native
vegetation to grow in the channel itself outside
of the impounded reaches. Vegetation can help
to improve water quality, as well as providing
habitat for wildlife and is visually appealing. If a
Safe Harbor Agreement is established for this
development any vegetation could be managed
as needed for flood and other purposes without
falling afoul of endangered species legislation.

Planting and Vegetation Management at
Levees, Floodwalls, Embankment Dams,
and Appurtenant Structure (ELT 1110-2-
583), Section 4, Design Considerations,
which would be reviewed and approved
through the 408 permitting processes.
• Section 2.4.15 Public Services – Additional
substantiation should be included to confirm fire
and police services can maintain acceptable
service ratios, response times or other
performance objectives with the “influx of local
community and tourists.”
Refer to Section 6.4, Effects Found Not
to Be Significant. Also, the City of
Anaheim would be required to enter into
a separate Maintenance and Operations
Agreement with the City of Orange,
County of Orange, and Orange County
Water District for the long-term
maintenance and operation of the
project. See Mitigation Measure HYD-1.
• Section 2.4.17 Transportation – The project
should evaluate how the anticipated influx of
local community and tourist will affect or
interfere with an adopted emergency responses
plan or emergency evacuation plan. In addition,
the project description should include the
anticipated number of trips for construction and
operation generated by the project. Specifically,
the analysis should evaluate whether the
number of existing off-street parking facilities
can accommodate the anticipated influx of local
community and tourist.

Refer to Section 4.9, Transportation. The
project improves the existing active
transportation facilities along the project
boundaries and would be compatible with
the adjacent OCVIBE project.

OC Environmental Resources
• Projects that, as part of a common plan of
development, disturb one or more acres are
required to obtain coverage under the General
Permit for Discharges of Storm Water Associated
with Construction Activity, Order 2009-0009-
DWQ (and subsequent Order 2022-0057-DWQ)
and implement a Storm Water Pollution
Prevention Plan (SWPPP) and monitoring
program consistent with permit requirements.

Refer to Section 4.7, Hydrology and
Water Quality.
• Specific mention should be made of whether the
project qualifies as a Priority Development
Project under the city’s municipal stormwater
permit (Santa Ana Regional Board Order R8-
2009-0030), or instead is a Non-Priority Project
which would require preparation of a NonPriority Water Quality Project Plan.

Refer to Section 4.7, Hydrology and
Water Quality. The project would be
designed to comply with the North
Orange County TGD and Model WQMP
to achieve MS4 permit compliance.

Chapter 1: Introduction
Final EIR No. 357 1-13 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• New development projects that create 10,000
square feet or more of impervious surface require
the development of a Water Quality Management
Plan (WQMP). Specific mention should be made
of applicable city WQMP requirements for projects
to comply with their municipal stormwater permits.

Refer to Section 4.7, Hydrology and Water
Quality. The project would be designed to
comply with the North Orange County TGD
and Model WQMP to achieve MS4 permit
compliance.
• Specific mention should be made of the Orange
County Stormwater Program’s Drainage Area
Management Plan (DAMP). The DAMP is Orange
County’s principal policy and program guidance
document for stormwater management and
includes a 2017 Technical Guidance Document to
be followed in preparing the project’s WQMP.

Refer to Section 4.7, Hydrology and Water
Quality. Section 4.7.1.1, Regulatory Setting.
• Specific mention should be made of the
potential water quality impacts from the project
and identification of the anticipated pollutants to
be generated or mobilized by the project should
be provided.

Refer to Section 4.7, Hydrology and Water
Quality. The project would be designed to
comply with the North Orange County TGD
and Model WQMP to achieve MS4 permit
compliance, which would address water
quality concerns.
• In collaboration with the Orange County Water
District (OCWD) and the OC Sanitation District
(OC San) efforts to minimize urban runoff impacts
to Orange County waters, OC Public Works
continues to research low-flow, dry-weather
season diversion project opportunities. OC Public
Works is participating in the OC San Urban
Runoff Optimization Study, which will identify,
evaluate, and develop additional urban runoff
diversion opportunities. Should any potential
sanitary sewer diversions be considered for the
surrounding storm drains around the OC River
Walk Project, a permit from OC San would be
required along with coordination with the Orange
County Stormwater Program’s Technical
Advisory Committee (TAC), which is
administered by OC Environmental Resources.

Diverted urban flows that are discharged into the
sanitary sewer system would also be counted
towards the collective 10 million gallons per day
fee-waived allowance that is shared among the
Orange County Permittees (County of Orange,
Orange County Flood Control District (OCFCD),
and cities). Other types of diversion projects,
such as the Chantilly storm drain to Burris Basin,
should also be coordinated with OC Public Works
and potentially the Orange County Stormwater
Program’s Watershed Improvement Projects
Subcommittee (WIPS) referenced in the project’s
engineering feasibility study.

Comment is noted. The City will coordinate
with OCSAN related to review and permit
for any potential sanitary sewer diversions
surrounding storm drains around the OC
River Walk Project, along with coordination
with the Orange County Stormwater
Program’s Technical Advisory Committee.

Chapter 1: Introduction
Final EIR No. 357 1-14 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• The OC River Walk Project is supplied by
treated water from the OCWD’s Groundwater
Replenishment System that will be discharged
into the Santa Ana River. National Pollution
Discharge Elimination System (NPDES)
permitting is anticipated to be required from the
Santa Ana Regional Water Quality Control
Board such as through an individual NPDES
permit or other de minimis discharge permit.

The discharge operations for the project and
associated NPDES permit should be
coordinated with OCFCD through the
encroachment permit, in addition to other
impacted regulatory agencies.

Refer to Section 4.7, Hydrology and
Water Quality, Section 4.7.4.1.
• The project should evaluate how large high-flow
offsite discharges, such as an emergency
response from a fire, sanitary sewer release,
illegal discharge, or water main break, would be
addressed in the surrounding drainages if
diverted or cut off from the Santa Ana River. For
example, a large-scale fire and multi-agency
water pollution response event occurred in this
reach of the Santa Ana River in February 2022.

Refer to Section 4.7, Hydrology and
Water Quality, Section 4.7.4.1.

OC Parks – Trail and Adjacent Areas:
• All costs and responsibilities for OC River Walk
elements that are proposed on County property,
including but not limited to planning, permitting,
construction, operation, maintenance and public
safety, shall be borne by the City, and be fully
compatible with flood control requirements and
subject to a land lease acceptable to and
approved by the Orange County Board of
Supervisors.

The City of Anaheim would be
responsible for the implementation of the
OC River Walk Conceptual Master Plan,
including but not limited to planning,
permitting, construction, operation,
maintenance, and public safety, as
described and discussed throughout the
EIR. The project is required to be fully
compatible with flood control
requirements and subject to and
approved by the Orange County Board of
Supervisors, as applicable.

Furthermore, the City of Anaheim would
be required to enter into a separate
Maintenance and Operations Agreement
with the City of Orange, County of
Orange, and Orange County Water
District for the long-term maintenance
and operation of the project. See
Mitigation Measure HYD-1, Section 4.7,
Hydrology and Water Quality.

Chapter 1: Introduction
Final EIR No. 357 1-15 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• The term “alternative modes of transportation” is
used throughout the document as something
encouraged on the trails through the project
area but is not defined. In the event this is
intended to include motorized modes of transit
such as e-bikes and e-scooters, it should be
noted that on this portion of the trail system only
Class 1 and 2 e-bikes are permitted.

The project would be operated in compliance
with the existing SART operating rules and
would therefore only permit Class 1 and
Class 2 e-bikes, as stated.
• The “Active (AT) Transportation” improvements
described as it relates to the Santa Ana River
Trail (SART) and other proposed trail segments
is not well defined, so additional detail is
needed, including defined conceptual
development plans to identify/depict those
improvements, to understand the impact of
those improvements.

Refer to Chapter 2, Project Description,
Section 2.4, and the OC River Walk
Conceptual Master Plan (May 2025),
available on the City’s website.
• Additional detail is needed on which trail areas
are proposed to be expanded to understand the
level of physical impact that would occur within
the trail areas, in order for the County to
comment as it relates to our existing
easements.

Refer to Chapter 2, Project Description,
Section 2.4, and the OC River Walk
Conceptual Master Plan (May 2025),
available on the City’s website.
• Additional detail is needed on the new
pedestrian bridge identified that provides bike
and pedestrian access across the river, as it is
not clear how this bridge will interface with the
existing trail locations.

Refer to Chapter 2, Project Description,
Section 2.4, and the OC River Walk
Conceptual Master Plan (May 2025),
available on the City’s website.
• Landscaping enhancement is identified as being
a component of the project, but it is not clear
what the enhancement will include and in what
areas landscaping would be occurring as it is
not defined in the plan. Additional detail
regarding how the City will address this is
needed for OC Parks to provide necessary
feedback.

Refer to Chapter 2, Project Description,
Section 2.4, and the OC River Walk
Conceptual Master Plan (May 2025),
available on the City’s website.
• Placing the SART on the East levee South of
Katella to Orangewood may cause concern for
multiple agencies. The service road is heavily
used by OC Public Works (OCPW), OC Flood
Control District (OCFCD), OC Watershed, OC
Sheriff, and other agencies and contractors that
utilize the Collins Yard, the OCFCD Storage
yard, the OCPW and OC Parks SART Storage
facility, and the OC Sheriff Training Facility. The
East side, due to its heavy utilization as a
service road, generates concerns related to
incompatible use and potential safety concerns.

Comment is noted. Section 2.1.1,
Existing Land Uses, describes the
current uses of the maintenance road on
the east side.

Chapter 1: Introduction
Final EIR No. 357 1-16 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
• It is important for the City to address unwanted
activities related to security, debris removal, and
transient management as it relates to the addition of
features accessible to the public and plan methods
to minimize those impacts.

The City of Anaheim would be required to
enter into a separate Maintenance and
Operations Agreement (MOA) with the City
of Orange, County of Orange, and Orange
County Water District for the long-term
maintenance and operation of the project.

The MOA will specify maintenance and
operating details related to security, debris
removal, and transient management. See
Mitigation Measure HYD-1.
• Additional detail is needed on the proposed new trail areas and how additional improvement to the
existing trail will interface with the surrounding uses, for the County to provide necessary feedback.

Refer to Chapter 2, Project Description,
Section 2.4, and the OC River Walk
Conceptual Master Plan (May 2025),
available on the City’s website.
• Operating hours for the River Walk were not
identified. The SART is closed at sunset, therefore if
the design will encourage or allow use of the trail
system outside the existing hours of operation, the
City would need to make considerations for
operating the River Walk that would take that into
account.

Any recreation elements would generally
operate between 5:30 a.m. and 10:30 p.m.,
which aligns with the City of Anaheim’s
standard operating schedule. The City of
Orange’s standard park operating hours are
from 5 a.m. to 11 p.m. The SART operating
hours will not change. It should be noted that
the actual operating hours would be
determined as part of the future maintenance
and operations agreement(s). See Mitigation
Measure HYD-1, Section 4.7, Hydrology and
Water Quality.

California Department of
Transportation, RegionalLDR-Transit Planning
• Consider incorporating bicycle parking if there are
opportunities to do so.

The project plans are conceptual at this time.

Bicycle parking will be incorporated where
feasible during the final site design phase.
• Continue to incorporate Complete Streets in project
development, including connections to existing and
proposed active transportation facilities in the project vicinity.

The project would improve the existing Santa
Ana River Trai and provide more accessible
and safe bike and pedestrian trail
connection, thereby supporting the Complete
Streets planning policy.
• Consider the need for more accessible and
connected transportation system for achieving
Caltrans’ vision for equity.
• Consider the need for equitable access to amenities
and resources, and consider referencing the City’s
own General Plan Environmental Justice Element.

The project would be open to all residents
and visitors. Providing improved pedestrian
and bike access would support providing
more accessible and connected
transportation system and community
recreation amenities.
• Any work performed within Caltrans right-of-way
(R/W) will require discretionary review and approval
by Caltrans and an encroachment permit will be
required for any work within the Caltrans R/W prior
to construction.
• Project plans and traffic control plans must be
stamped and signed by a licensed engineer.

Caltrans is listed as one of the responsible
agencies and review and approval of access
and encroachment permits within Caltrans
R/W will be processed.

Chapter 1: Introduction
Final EIR No. 357 1-17 November 2025
OC River Walk Project
Table 1-1. NOP Comment Summary
Commenting Agency Summary of Comments
Responses/EIR Sections
Where Issues Addressed
California Department of
Transportation, Division of
Aeronautics
Indicates that the Fullerton Municipal Airport is 10.5
miles from the project site.

The project site is approximately 10.5
miles from the Fullerton Airport, and is
outside of Fullerton Airport Land Use
Plan airport influence area.

Southern California of
Association of
Governments
SCAG provided information related to Connect
SoCal (2020-2045 Regional Transportation
Plan/Sustainable Communities Strategies) to
determine consistency with the project.

SCAG approved the 2024-2050 Connect
SoCal in April 2024, after the NOP/IS was
released. Appropriate discussion and
consistency with the 2024-2050 is included
in Chapter 3, Environmental Setting.

Native American Heritage
Commission
• Recommends consultation with California
Native American tribes that are traditionally and
culturally affiliated with the geographic area of
the project site.
• Includes requirements under Assembly Bill 52
and Senate Bill 18.

See Section 4.10, Tribal Cultural
Resources.

1.5.2 Draft Environmental Impact Report and Public Review Pursuant to CEQA Guidelines, Section 15105, this Draft EIR is being circulated for public review and comment for a period of 45 days. During this period, the public and public agencies can submit comments on this EIR’s accuracy and completeness to the lead agency. The 45-day public review period for this Draft EIR will be from July 24, 2025, through September 8, 2025. The public can review this Draft EIR at the following address during normal business hours (Monday through Friday, Business Hours: 8:00 a.m. to 4:00 p.m.) or on the City of Anaheim’s website at www.anaheim.net/876/Environmental-Documents.

Anaheim City Hall
Community Services Department, Parks Division
200 South Anaheim Boulevard, Suite 433
Anaheim, California 92805
The City of Anaheim encourages all comments on this Draft EIR to be submitted in writing.

Comments or questions regarding this Draft EIR should be addressed to the following:

City of Anaheim – City Hall
Community Services Department, Parks Division
Attn: Ana Straabe, Principal Project Planner
200 South Anaheim Boulevard, Suite 433
Anaheim, California 92805
(714) 765-4463
[email protected]
Chapter 1: Introduction
Final EIR No. 357 1-18 November 2025
OC River Walk Project

1.5.3 Final Environmental Impact Report and Certification Upon completion of the Draft EIR public review period, a Final EIR will be prepared. Pursuant to CEQA Guidelines, Section 15132, the Final EIR will consist of (1) the Draft EIR; (2) the comments and recommendations received on the Draft EIR; (3) a list of people, organizations, and public agencies that commented on the Draft EIR; (4) the City of Anaheim’s responses to significant environmental points raised by the public and agency comments submitted during the review and consultation process; and (5) any other information the City of Anaheim has added to the Draft EIR. The Final EIR will also include a Mitigation Monitoring and Reporting Program prepared in accordance with CEQA (California Public Resources Code, Section 21081.6). Before the City of Anaheim can review the project for approval, it must first certify that the EIR has been completed in compliance with CEQA, that it has reviewed and considered the information in the EIR, and that the EIR reflects the independent judgment of the City of Anaheim. The City of Anaheim will also be required to adopt Findings of Fact and a Statement of Overriding Considerations (if any significant, unavoidable impacts are identified). If no significant, unavoidable impacts (assuming the City of Anaheim finds the proposed mitigation measures to be feasible) are identified, the City of Anaheim will not be required to adopt a Statement of Overriding Considerations if it approves the project (California Public Resources Code, Section 21081).

1.6 Documents Incorporated by Reference
CEQA Guidelines, Section 15150, allows for incorporation by reference of “all or portions of another document which is a matter of public record or is generally available to the public.” Incorporation by reference is used principally as a means of reducing the size of EIRs. This EIR relies in part on data, environmental evaluations, mitigation measures, and other components of EIRs and plans prepared by the City of Anaheim for areas in the project vicinity. These documents are listed here and used as source documents for this EIR. These documents are available for public review during normal business hours (Monday through Friday, 8:00 a.m. to 5:00 p.m.) at The City of Anaheim’s Community Services Department located at 200 S. Anaheim Boulevard Suite 443, and on the City of Anaheim’s website at www.ocriverwalk.com. • City of Anaheim General Plan (City of Anaheim 2004a)
• City of Anaheim General Plan EIR (City of Anaheim 2004b) • City of Orange General Plan (City of Orange 2010a)
• City of Orange General Plan EIR (City of Orange 2010b) • County of Orange General Plan (County of Orange 2012 [as updated]) • Orange County Water District Recycled Water Conveyance Improvement Project Draft Initial Study/Mitigated Negative Declaration (OCWD 2022) • Addendum No. 11 to the Revised Platinum Triangle Expansion Project Final Subsequent Environmental Impact Report No. 339 (City of Anaheim 2022) Chapter 1: Introduction
Final EIR No. 357 1-19 November 2025
OC River Walk Project
• Addendum No. 13 to the Revised Platinum Triangle Expansion Project Final Subsequent Environmental Impact Report No. 339 (City of Anaheim 2024). • OC River Walk Engineering Feasibility Study (PACE 2021). • OC River Walk Conceptual Master Plan (PACE 2025)

1.7 Scope of the Environmental Impact Report
Based on a review of the project and comments received during the NOP public review period and preparation of an Initial Study (Appendix A), the City of Anaheim determined that an EIR that addresses the following environmental issue areas should be prepared. Other environmental issues identified in Appendix G of the CEQA Guidelines have been scoped out from further analysis, as they were determined to have no impact or less than significant impact in the Initial Study prepared during the Notice of Preparation process. Environmental issues found to have no or less than significant impacts are also included in Section 6.4, Effects Found Not to Be Significant. • Air Quality
• Biological Resources
• Cultural Resources
• Geology and Soils
• Greenhouse Gas Emissions
• Hazards and Hazardous
Materials
• Hydrology and Water Quality
• Noise
• Transportation
• Tribal Cultural Resources
The specific topics evaluated are detailed in Chapter 4, Environmental Analysis, of this EIR (Sections 4.1 through 4.10).

This EIR evaluates direct impacts, reasonably foreseeable indirect impacts, and cumulative impacts resulting from planning, construction, and operation of the project using the most current information available and in accordance with the provisions set forth in CEQA and the CEQA Guidelines. In addition, this EIR recommends potentially feasible mitigation measures, where possible, and project alternatives that would reduce or eliminate significant, adverse environmental effects.

Chapter 5, Alternatives, of this EIR was prepared in accordance with Section 15126.6 of the CEQA Guidelines. CEQA requires that the lead agency adopt mitigation measures or alternatives, where feasible, to substantially lessen or avoid significant environmental impacts that would otherwise occur. However, project modification or alternatives are not required where significant environmental impacts would not occur.

This EIR evaluates the alternatives to the project as detailed in Chapter 5. • Alternative 1: No Project/No Improvements Alternative. Under the No Project/No Improvements Alternative, none of the Group A, B, C, or D improvements as defined in Chapter 2, Project Description, would occur. Group A includes Impoundments, Chapter 1: Introduction
Final EIR No. 357 1-20 November 2025
OC River Walk Project
Storm Drain Diversions, and Embankments; Group B includes New Pedestrian/Bike Bridges; Group C includes New Trails and Trail Improvements; and Group D includes Enhanced Community Recreation Amenities.
• Alternative 2: Group A and C Impoundments and Trails Alternative. Under this Alternative, only the Group A and Group C improvements as defined in Chapter 2 would be constructed.

1.8 Organization of the Environmental Impact Report
This EIR is organized into two parts. The Draft EIR addresses the potential environmental impacts of the physical development of the project and associated technical appendices in part 1. When the EIR is finalized, the Final EIR will contain the public, organization, and public agency comments received on the Draft EIR, the City of Anaheim’s responses to those comments, a summary of EIR revisions or enhancements, and the Mitigation Monitoring and Reporting Program for the project.

This Draft EIR includes the following:

Executive Summary. Summarizes the project, environmental impacts that would result from implementation of the project, proposed mitigation measures that would avoid or reduce impacts, and the level of significance of impacts both before and after mitigation.

Chapter 1, Introduction. Provides an introduction and overview of this EIR process and describes the intended use and scope of this EIR and the review process.

Chapter 2, Project Description. Provides a detailed description of the project, including its location; background information; project objectives; technical, economic, and environmental characteristics; and intended uses for this EIR.

Chapter 3, Environmental Setting. A description of the physical environmental conditions in the vicinity of the project as they existed at the time the notice of preparation was published, from local and regional perspectives. These provide the baseline physical conditions from which the lead agency determines the significance of the project’s environmental impacts.

Chapter 4, Environmental Analysis. Describes the baseline environmental setting and provides an assessment of potential project impacts for each environmental issue area presented. Each section is divided into nine subsections: Environmental Setting; Thresholds of Significance; Plans, Programs, and Policies; Environmental Impacts; Cumulative Impacts; Level of Significance before Mitigation; Mitigation Measures; Level of Significance after Mitigation, and References.

Chapter 5, Alternatives. Describes and compares the proposed alternatives to the project.

Chapter 6, Other CEQA Considerations. Provides information required by CEQA regarding impacts that would result from the project, including a summary of cumulative impacts; secondary impacts, Chapter 1: Introduction
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including potential impacts resulting from growth inducement; and significant, irreversible changes to the environment.

Chapter 7, Individuals and Agencies Consulted. Lists the individuals and agencies that were consulted during the preparation of this EIR.

Chapter 8, References. Provides a list of references used in preparation of the analysis presented in this EIR.

Appendices. Includes various documents and data that support the analysis presented in this EIR.

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Chapter 2 Project Description
The purpose of this chapter is to describe the OC River Walk Project (project) for the public, reviewing agencies, and decision-makers. According to Section 15124 of the California Environmental Quality Act (CEQA) Guidelines, a complete project description must contain the following information: (1) the precise location and boundaries of the project, as shown on a detailed project site map and a regional map; (2) a statement of the objectives sought by the project; (3) a description of the project’s technical, economic, and environmental characteristics; and (4) a statement of the intended uses of the Environmental Impact Report (EIR), including discretionary actions. This chapter also includes a list of agencies expected to use the EIR in their decisionmaking and a list of permits and other approvals required to implement the project.

2.1 Project Location and Setting
The project site is located along the Santa Ana River corridor, generally extending from Orangewood Avenue north to Ball Road and the existing Anaheim Coves at Burris Basin. It generally encompasses approximately a 2-mile stretch of the Santa Ana River, covering approximately 111 acres. It is approximately 15 miles upstream from the Pacific Ocean and adjacent to Angel Stadium, Anaheim Regional Transportation Intermodal Center (ARTIC), the Honda Center, and the Arena Corporate Center (ACC) buildings on the west side in the City of Anaheim. The ARTIC, the Honda Center, and the ACC buildings are all part of the OCVIBE Master Site Plan Project (OCVIBE Project). On the east side of the Santa Ana River, in the City of Orange, the project is near the Sandra Hutchens Regional Law Enforcement Training Center (a facility that includes a combat shooting range), the Orange County Public Works (OCPW) offices, the Stadium Promenade shopping mall, the Extended Stay America – Orange, and the Kinder Morgan Orange Terminal. The project site’s regional setting is shown on Figure 2-1, Regional Location, while a closer view of the site and the surrounding local vicinity is shown on Figure 2-2, Local Vicinity.

The project is primarily located in the City of Orange and partially located in the City of Anaheim, with many different landowners and jurisdictional bodies. Figure 2-3, Project Site and Adjacent Ownerships, shows the ownership of the project site and adjacent properties. As shown on Figure 2-3, the Santa Ana River is within the Orange County Water District’s (OCWD) jurisdiction north of the Union Pacific Railroad (UPRR) and within the Orange County Flood Control District’s (OCFCD) jurisdiction south of the UPRR. Within the boundaries of the project site, five overcrossings and/or bridges span the Santa Ana River: Ball Road Bridge, UPRR overcrossing, Katella Avenue Bridge, Metrolink/Los Angeles-San Diego-San Luis Obispo Rail Corridor (LOSSAN Corridor) railroad overcrossing, and Orangewood Avenue Bridge. Additionally, State Route (SR-) 57 crosses the Santa Ana River.

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2.1.1 Existing Land Uses
The Santa Ana River is the largest watershed drainage south of the Sierra Nevada, approximately 2,700 square miles and 100 miles in length, with more than 50 tributaries connecting to it. The U.S. Army Corps of Engineers (USACE) Santa Ana River Mainstem Project, documented in the 1988 General Design Memorandum, was designed and constructed in the 1980s with the main purpose of flood protection and flood risk reduction to protect Southern California from large storm events. The Santa Ana River within the project site boundaries is composed of a rock-lined embankment and soil-bottomed trapezoidal-shaped channel that functions primarily as a flood protection structure, providing stormwater conveyance and water resource management and protecting the adjacent lands from flooding. It was designed to provide protection for a Standard Project Flood, which is equal to a 190-year storm event. It has an average base width of 320 feet, rock-lined side slopes of 2:1, and an unlined soil/sand bottom. Hydrologically, it is a prime watershed location for aquifer recharge. Two reinforced concrete drop structures1 in the Santa Ana River are within the project site, approximately 7 feet high and stretching across the bottom of the riverbed: one between Ball Road and UPRR and another between the Metrolink/LOSSAN Corridor and SR-57. The public is not authorized to be within the Santa Ana River channel or on the channel’s grouted rip-rap embankments.

The northern end of the project site connects to the existing Anaheim Coves, a joint project between the City of Anaheim, OCWD, and Southern California Edison (SCE). Anaheim Coves was completed in 2019 and is a 26-acre nature park that offers approximately 2.5 miles of multiuse trail, fitness zones, native habitat, educational elements, and nature play area. The Anaheim Coves trail extends north along the edge of Burris Basin, an offline (not in main flow path of the river) water recharge/storage basin just north of Ball Road adjacent to the project site and the Santa Ana River. Figure 2-4, Existing Project Site Views, and Figures 2-4a through 2-4d show existing views of the Santa Ana River looking south at four vantage points.

Existing Santa Ana River Trail and Maintenance Road
The existing Santa Ana River Trail (SART) runs along the east bank on top of the existing river embankment north of Katella Avenue and along the west bank on top of the existing river embankment south of Katella Avenue. A connection between the east and west banks is provided on the northern side of Katella Avenue Bridge, which links to the SART underpass at Katella Avenue. In addition to the Katella Avenue underpass on the western embankment, there are existing underpasses at SR-57 and Orangewood Avenue within the project site boundaries on the west bank. On the eastern side, the SART includes two underpasses within the project site 1 Drop structures were constructed as part of the U.S. Army Corps of Engineers Santa Ana River Mainstem Project in the 1970s to provide enhanced flood protection for the region. By creating a sudden drop in elevation of the riverbed, drop structures control the velocity of the flowing water and reduce the water’s energy to prevent erosion of the riverbed and banks, increasing flood protection and stability.

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boundaries that allow for uninterrupted bike and pedestrian passage: one under UPRR and another under Ball Road. An approximately 8.3-acre area owned by the County of Orange/OCFCD provides nearly 200 feet of open space adjacent to the SART on the east bank. The existing SART, including underpasses, is shown on Figure 2-5, Existing Condition – Surface.

The west bank has a maintenance road extending north from Katella Avenue, which crosses under Ball Road and continues along the west bank of the river north of the project boundary. The existing maintenance road on the west bank includes one underpass at Ball Road and multiple access ramps down to the riverbed within the project site boundaries. South of Katella Avenue, there is a maintenance road along the east bank of the river with multiple access ramps down to the riverbed within the project site boundaries. These maintenance roads and access ramps, shown on Figure 2- 5, are heavily utilized by OCPW, OCWD, OC Watershed, Orange County Sheriff Department, and OCFCD to monitor and maintain the river and to utilize the Collins Yard, the OCFCD Storage Yard, the OCPW and Orange County Parks SART Storage facility, and the Orange County Sheriff Training Facility. They are used by vehicles only and fenced off when not in use.

Existing Underground Utilities
Several storm drains outlet into the Santa Ana River, as shown on Figure 2-6, Existing Condition – Underground. The Collins Channel, an existing channelized tributary, also outlets into the Santa Ana River between Katella Avenue and the Metrolink/LOSSAN Corridor from the eastern side.

Additionally, the existing groundwater replenishment system (GWRS) pipeline runs along the west bank of the Santa Ana River.

The Orange County Sanitation District (OCSAN) operates the Santa Ana River Interceptor sewer pipeline, which runs along the east bank from the northern boundary of the project site to the Metrolink/LOSSAN Corridor, where it crosses the Santa Ana River and continues south along the west bank. A smaller OCSAN trunk sewer line crosses the river at Katella Avenue and continues west to State College Boulevard.

2.1.2 Surrounding Land Uses
On the west side of Santa Ana River, the project site south of Katella Avenue is adjacent to various urban land uses, such as Angel Stadium, the ARTIC, and a proposed linear park planned by the City of Anaheim north of Orangewood Avenue between Angel Stadium and the Santa Ana River in the City of Anaheim. The project site north of Katella Avenue is adjacent to the Honda Center, the ACC office buildings, the vacant former Ball Road Basin, and The Islands Golf Center. The Honda Center is an indoor arena, the home of the Anaheim Ducks of the National Hockey League, that hosts a variety of sports and entertainment events. The Islands Golf Center is a golf facility set on a water basin with hitting stalls, floating targets, and putting greens for practice. North of the project site is Burris Basin, an offline (not in main flow path of the river) OCWD groundwater recharge basin, and Anaheim Coves, a nature park with 2.5 miles Chapter 2: Project Description
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of multi-use trails. The former Ball Road Basin is conceptually being considered by the City of Anaheim to be developed as a mixed-use project with a high-density residential component.

The OCVIBE Project area includes approximately 92.08 net acres and extends from the Southern California Edison Easement area to the north, State Route 57 to the west, the confluence of the State Route 57 and the Santa Ana River to the south, and the Santa Ana River to the east. The OCVIBE Project is adjacent to the OC River Walk. The OCVIBE Project is a mixed-use development with up to 2,250 residential units, 576,680 square feet of office, 1.7 million square feet of commercial space, and open space to be developed in multiple phases. Phase I of the OCVIBE Project began construction in the second quarter of 2024, which includes construction of new streets and infrastructure, parking structures, an office building, market hall, concert hall, and an urban park. All phases of the OCVIBE Project are expected to be completed by 2032.

The uses south of Katella Avenue that are adjacent to the Santa Ana River on the eastern side include the Sandra Hutchens Regional Law Enforcement Training Center (a facility that includes a combat shooting range), the OCPW offices, and other various industrial park uses. The surrounding uses north of Katella Avenue are industrial, office, entertainment, and hotel uses, including the Stadium Promenade shopping mall and the Kinder Morgan Orange Terminal in the City of Orange (refer to Figure 2-4).

2.2 Project Objectives
In accordance with Section 15124(b) of the CEQA Guidelines, the City of Anaheim, as the lead agency, identified the following objectives for the project:

1. Adopt the OC River Walk Conceptual Master Plan to further enhance and accentuate existing recreational areas, facilitate pedestrian and bicycle access, and promote the use of the river corridor open space area for the community benefit.

3. Provide seamless and cohesive improvements across jurisdictions on the project site to benefit the public and the area’s aesthetics.

4. Implement projects to transform and improve the river and riverbed’s groundwater recharge potential and improve the river corridor’s ecology (flora and fauna).

5. Maintain and enhance flood protection capacity and resiliency.

6. Enhance connectivity and community access by leveraging the project site's location near ARTIC, major entertainment venues, and adjacent mixed-use developments.

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2.3 Project Background and Purpose
In 2021, the OC River Walk Engineering Feasibility Study (Feasibility Study) identified 17 design opportunities along the Santa Ana River within the project site. The opportunities outlined in the Feasibility Study align with the USACE Operating Principles, as well as the California State Coastal Conservancy's Santa Ana River Conservancy Program goals of (1) protection and preservation of water resources through multi-benefit projects, (2) habitat and wildlife preservation and enhancement, and (3) equitable education and recreation access. The 17 opportunities were split into three categories and outlined in the Feasibility Study as shown below.

Active Transportation
• Bikeway/pedestrian trail extension: Katella Avenue to Anaheim Coves (including UPRR undercrossing) along the west bank of the river
• Trail culvert undercrossing at Ball Road
• SART east bank addition of river from Katella Avenue to Orangewood Avenue • Bike/pedestrian bridge across the Santa Ana River
• River Walk width expansion and connectivity
• Widen existing bridges for bikes/pedestrian lanes
• SART pinch point relief (two locations)
River Activation
• River impoundments (inflatable rubber dams north of Orangewood and north of ARTIC)
• Riverbank modifications
• Urban stormwater treatment
• River recreation/programming
Community Amenities
• Cantilever decks
• Engagement with adjacent spaces
• Stepped river embankment
• Integrated public education/art
• Upland habitat restoration
• Landscape enhancements
Opportunities, as outlined in the Feasibility Study, are defined as individual projects with specific locations or typologies that can be applied to multiple locations. The Feasibility Study served as the launching point for the OC River Walk Conceptual Master Plan and design documents for multiple projects within OC River Walk. The integrated purposes of the OC River Walk Conceptual Master Plan are as follows:

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1. Increase public recreation and connectivity by creating and improving a robust active transportation network.

2. Catalyze economic growth and development by implementing flexible public spaces and strengthening connections to adjacent communities.

3. Increase water resource resilience and recreational activities by creating two water recharge impoundments created by three inflatable rubber dams.

4. Enhance the ecology of the river and surrounding region with native upland planting and increased open space where possible.

5. Improve visual and physical public access to the river.

6. Maintain and enhance flood protection capacity and resiliency.

7. Use varying means of media to integrate public art to provide a deeper meaning and connection with the river and education programming to convey the significance and history of the river to elevate the visitor experience and identity of the project.

8. Prioritize safety by enhancing connectivity and using site lighting to improve visibility and sense of safety.

2.3.1 Orange County Water District Groundwater Replenishment System Turnout Structure
On May 18, 2022, the OCWD adopted the Initial Study/Mitigated Negative Declaration (IS/MND) for the Recycled Water Conveyance Improvement Project. This project includes the installation of an outlet facility (referred to as a turnout or pipeline turnout structure) to enable the diversion of treated water from the GWRS into the Burris Basin for groundwater recharge. It also includes modifying the existing operational protocol for releasing GWRS water into the Carbon Creek Diversion Channel. For discharge in the SAR, a National Pollution Discharge Elimination System (NPDES) permit from the Regional Water Quality Control Board (RWQCB) and an amendment to OCWD’s existing Title 22 Reuse permit from Division of Drinking Water to allow impoundment of GWRS water within the SAR. Currently, ultra-pure water from the GWRS discharges at a rate of 100 million gallons per day (MGD) into four OCWD recharge basins upstream of the project site.

The GWRS turnout structure is planned to be located in the southeastern portion of the Burris Basin, adjacent to the Santa Ana River, and is included within The OC River Walk project site. The Burris Basin, an existing groundwater recharge basin owned and operated by the OCWD, is part of the OCWD’s recharge system network in central Orange County. An existing GWRS pipeline that varies between 66 and 60 inches extends from the OCWD’s GWRS plant in Fountain Valley, running along the Santa Ana River embankment to other recharge basins north of Burris Basin. From the Burris Basin, the OCWD can use the Burris Pump Station to move ultra-pure water to the Santiago Basin, further supporting groundwater recharge.

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The project would require modifications to this turnout structure, allowing additional options to discharge into either the pipeline leading to the two impoundments or directly into the river, thereby supplying ultra-pure GWRS water to the impoundments.

2.4 Project Components
The OC River Walk Conceptual Master Plan (PACE 2025) consists of various multi-purpose improvements to transform the Santa Ana River corridor and portions of the existing SART, along with related off-site improvements necessary for its implementation. The main components of the OC River Walk Conceptual Master Plan involve creating two water impoundments by installing three inflatable rubber dams, modifying the riverbanks, constructing two pedestrian/bike bridges, providing new trails, improving existing trails, creating new and protection of existing access ramps, constructing two new undercrossings on the west bank at the UPRR and the Metrolink railroad, providing enhanced community recreation amenities (e.g., terraced seating, nature play areas, parklets, plazas, gathering areas for large-scale events, festivals, and other activities, water access, kayak launch, etc.), and other improvements. Figure 2-7, Proposed Impoundments and Trail Improvements, illustrates the impoundments and storm drain diversion, and trail improvement components of the OC River Walk Conceptual Master Plan. Figure 2-8, Overall Project Elements, illustrates the active transportation and river activation components, including approximate locations for enhanced recreational facilities and potential future park areas. These improvements would require the implementation of 19 project elements, as listed in Table 2-1, OC River Walk Conceptual Master Plan Elements, and illustrated on Figures 2-8a through 2-8d, which have been categorized into four groups: Group A – Impoundments, Storm Drain Diversions, and Embankments; Group B – New Pedestrian/Bike Bridges; Group C – New Trails and Trail Improvements; and Group D – Enhanced Community Recreation Amenities. The project conforms with the design goals and function of the SAR described in the USACE 1988 General Design Memorandum. The project design (e.g., levee design, vegetation, and freeboard) would be reviewed and permitted by the USACE and the OCFCD through the 408 permitting process.

Table 2-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 Group A: Impoundments, Storm Drain Diversions, and Embankments 1 River Impoundments
1a North Impoundment and Inflatable Rubber Dam
3,000' length, 22 ac area,
110 AF volume
Rubber Dam: 8' x 300'
1b North Impoundment – Rubber Dam Concrete Foundation
310' x 24' x 2' = 700 CY reinforced concrete
10,000 CY of earthwork subgrade
preparation
1c North Impoundment – Rubber Dam Air Compressor, Controls, and Flow Bypass
10' x 10' x 7' precast concrete vault or
building (preferred)
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Table 2-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 1d South Impoundment and Inflatable Rubber Dam
1,700' length, 11.5 ac area,
90 AF volume
Rubber Dam: 10' x 300'
1e South Impoundment – Rubber Dam Concrete Foundation
310' x 24' x 2' = 700 CY reinforced concrete
10,000 CY of earthwork subgrade
preparation
1f South Impoundment – Rubber Dam Air Compressor, Controls, and Flow Bypass
10' x 10' x 7' precast concrete vault or
building (preferred)
1g Collins Channel – Inflatable Rubber Dam Rubber Dam: 6' x 45' 1h Collins Channel – Rubber Dam Concrete Foundation
60' x 24' x 2' = 130 CY
1,500 CY of earthwork subgrade
preparation
1i Collins Channel – Rubber Dam Air Compressor and Controls 10' x 10' x 7' precast concrete vault or building (preferred)

2. Impoundment Evacuation Pumps 4 pumps at 5 MGD ea. (20 MGD total), 85 HP ea. (340 HP total)

3. Pipeline from Pump Station to GWRS Turnout
(N. of Orangewood Avenue to Burris Basin) 8,000 LF, 30-40" HDPE

4. GWRS Turnout – Concrete Flow Control Structure with
Dechlorination Facilities (Located at South End of Burris Basin) – Off-Site Improvement
50 MGD

6. River Embankments 9,600 LF total
6a North Impoundment Embankment 6,200 LF, 23' avg. height to 26' max, up to 33' at drop structure
6b South Impoundment Embankment 3,400 LF, 23' avg. height to 26' max, up to 33' at drop structure
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Table 2-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1 Group B: New Pedestrian/Bike Bridges

1. Pedestrian/Bike Bridge North of Katella Avenue 400 LF, 36'-58' width, 3 River Piers

2. Pedestrian/Bike Bridge North of Orangewood Avenue 350 LF, 12'-18' width, 5 River Piers

3. Trail East Bank Katella Avenue to Ball Road 4,300 LF, 18' typ. width 3a Replace Access Road Only (For New Pedestrian/Bike Bridge North of Katella Avenue) N/A
3b Improve Trail w/ Terrace and Community Access 4,300 LF, 12'-40' width 3c East Bank Park/River Terrace Retaining Wall #1 500 LF, <8' height 3d City of Orange Water Recreation Opportunity1 N/A
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Table 2-1. OC River Walk Conceptual Master Plan Elements No. Conceptual Master Plan Elements Quantity (Approximate)1

4. Trail East Bank Katella to Orangewood: SART – Main Line Reroute to East Bank of River 4,000 LF, 18' typ. width
Group D: Enhanced Community Recreation Amenities

3. OCVIBE Lot B Parking Lot, Potential Future OC River Walk Park 2.2 ac

4. Park / River Terrace: East Bank North of Katella Avenue 4a East Bank (City of Orange) Katella Avenue to UPRR 8.3 ac 4b UPRR to Ball Road 2.2 ac

5. Riverbed Between Impoundments (future recreation TBD) 3.8 ac, 650 LF

6. Art / Education / Signage (Conceptual locations)
6a Iconic Signage1 TBD
6b Bridge Mural and Lighting at freeway underpass TBD
6c Mosaic / Art Installations TBD
6d Reflective Shade Canopies TBD
6e Zen Zone / Wildflower Spaces1 TBD
6f River Poetry Walk TBD
6g Interactive Educational Components TBD
6h Wayfinding Signage1 TBD
6i Conceptual Locations for Art/Signage Opportunities¹ TBD Notes: ac = acres; AF = acre-feet; CY = cubic yards; GPM = gallons per minute; HDPE = high-density polyethylene; HP = horsepower; LF = linear feet; MGD = million gallons per day; N/A = Not Applicable; TBD = to be determined; typ. = typical; UPRR = Union Pacific Railroad; All project dimensions and locations are approximate as of the time of EIR preparation and have been assumed for analysis purposes. 1 Project element is not specifically located at this time or encompasses the entire project site.

Stepped riverbank modifications may be considered to occur north of the UPRR adjacent to the former Ball Road Basin. The proposed trail improvements north of the UPRR would connect to the Anaheim Coves and create a trail and recreation connection between the OC River Walk and the Anaheim Coves.

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The OC River Walk Conceptual Master Plan includes 19 main project elements, as listed in Table 2-1. These elements are grouped into four categories, which include various project components.

For CEQA analysis, it is assumed that these various components could be implemented simultaneously or at different stages within an approximately 10-year period.

Additionally, all necessary new and/or upgrades to existing on- and off-site utilities and systems, such as electrical facilities, lighting, landscaping, irrigation, seating, and signage to implement various components of the project, would be provided in compliance with applicable City of Anaheim and City of Orange rates, rules, and regulations; municipal codes; the California Green Building Standards Code; and any applicable engineering standards and specifications, as deemed necessary by the approving agency. The key elements of the OC River Walk, organized into Groups A through D, are described below. The dimensions (e.g., lengths, heights, volumes) and locations specified in each element are approximate as of the time of EIR preparation and have been assumed for analysis purposes.

Public Law 84-99, Emergency Response to Natural Disasters, is the USACE’s basic authority to provide for emergency activities in support of state and local governments prior to, during, and after a flood event. Under PL 84-99, the USACE can provide both emergency technical and direct assistance in response to flood and coastal storms and can assist if there is a flood threat from damage caused by earthquakes to flood risk management projects. The SAR is currently eligible for Public Law 84-99 program coverage, and it should be noted that the project would not change this eligibility status.

Group A – Impoundments, Storm Drain Diversions, and Embankments There are six project elements in Group A, as described below and illustrated on Figure 2-8a, Proposed Improvements – Group A.

Element 1. Impoundments: The project includes two impoundments, bodies of water that would be maintained within the river for an extended period of time. These impoundments would be created by the installation of three inflatable rubber dams: (1) one approximately 8 feet high and 300 feet long, located approximately 200 feet north of the Metrolink/LOSSAN Corridor near ARTIC to produce the north impoundment; (2) one approximately 10 feet high and 300 feet long, approximately 250 feet north of Orangewood Avenue to produce the south impoundment; and (3) one approximately 45 feet long within Collins Channel to prevent impounded water from backing up into the tributary channel and serve as a barrier against dry weather flow entering the impoundments. Figure 2-9, Rubber Impoundments, illustrates the proposed impoundment dimensions. These rubber dams would create opportunities for additional groundwater recharge locations. They would be inflated during dry conditions, allowing the OCWD to discharge ultrapure water from their GWRS into the river and impound it upstream of the rubber dams. The water surface area from the tapered shoreline to the north impoundment would be 22 acres and Chapter 2: Project Description
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3,000 feet long, with an estimated water surface elevation (WSEL) of 153 feet and an estimated water volume of 110 acre-feet. The water surface area from the existing drop structure to the south impoundment would be approximately 11.5 acres and 1,700 feet long, with an estimated WSEL of 145 feet and an estimated water volume of 90 acre-feet. The impoundment section view is shown on Figure 2-9.

Approximately 12 MGD of ultra-pure water would recharge into the groundwater aquifer through these two impoundments. During storm events, the inflatable rubber dams would be deflated to maintain the river's hydraulic capacity for flood conveyance.

Element 2. Impoundment Evacuation Pumps: A large pump station and pipeline (Element 3) would be constructed at the southern end of the south impoundment, north of Orangewood Avenue, to pump ultra-pure water to Burris Basin, one of the OCWD's off-river spreading basins, when a storm approaches rather than discharging it to the ocean. The pump station would house four 85- horsepower evacuation pumps, each with a capacity of 5 MGD, totaling 20 MGD. The pump station would be electrically powered.

Element 3. Pipeline: An approximately 8,000-linear-foot, 30- to 40-inch high-density polyethylene pipeline would be constructed from the south impoundment pump station north of Orangewood Avenue to the turnout at Burris Basin (off site). Two fill lines with valves would connect the pipeline to the north and south impoundments so that this pipeline could be used to fill either impoundment. The pipeline would provide gravity flow for approximately 15 to 30 MGD of ultrapure water from the GWRS into the impoundments and provide a pathway to evacuate impounded water using the impoundment pump station (Element 2).

Element 4. GWRS Turnout Structure: A concrete flow control structure with dechlorination facilities, capable of handling a maximum of 50 MGD, would be constructed at the southern end of the Burris Basin. This structure would be connected by the 30- to 40-inch pipeline described in Element 3. The turnout structure has been proposed by the OCWD to discharge ultra-pure GWRS water into the Burris Basin. The OCWD adopted an IS/MND for the installation and operation of the GWRS turnout structure to the Burris Basin in May 2022. For the purposes of this project, the turnout structure approved by the OCWD would be modified to provide additional options to discharge either into the pipeline to the south impoundment pump station or directly into the river, supplying ultra-pure GWRS water for the impoundments.

Element 5. Storm Drain Diversions (Dry-Weather Flow): Several diversion stations would be provided to divert dry-weather flow away from the impoundments, either into a nearby sanitary sewer or downstream through gravity pipes or pump stations. A dry-weather storm drain diversion is a system that moves polluted water from storm drains into the sanitary sewer system for treatment. This would help to prevent any pollutants from entering the ultra-pure water in the impoundments. These facilities include storm drain outlets with flap gates, diversion manholes, Chapter 2: Project Description
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diversion pump stations, and pipes to existing sewer lines. An in-channel diversion structure would also be provided at Collins Channel. Pump stations would be electrically powered.

Element 6. River Embankments: Approximately 3.5 miles of riprap-lined riverbanks exist along the western and eastern sides of the Santa Ana River, between Ball Road and Orangewood Avenue.

Although riprap is highly functional for bank protection, modifications are proposed to improve versatility and usability by providing safe public access and engagement with the Santa Ana River while maintaining flood protection. Approximately 9,600 feet of embankment would be constructed on both the eastern and western sides of the north and south impoundments.

The existing riprap would be upgraded with soil cement and reinforced concrete construction methods, increasing stability and erosion protection for flood protection systems. Soil cement, up to 8 feet thick, would replace the current 18 to 24 inches of riprap, providing smoother integration with adjacent land uses and the river.

Embankment improvements to portions of the river outside the immediate vicinity of the two impoundments may be also necessary to facilitate other anticipated elements of the project, including trails, river access, and flood conveyance/flood protection. Improving and strengthening the base structure of the embankments would provide a consistent and stable foundation for these elements to be integrated into the river’s edge. Above and below the 100- year flood elevation, terraced concrete steps would be provided for public access, seating, landscaping, and other recreational uses (which are described further in Group C). Existing and proposed access ramps would ensure OCFCD and OCWD access. The project is intended to provide access for bulldozers and heavy equipment on the embankment around inflatable dams and drop structures by placing soil over the grade control structures.

Group B – New Pedestrian/Bike Bridges
There are three project elements in Group B, as described below and illustrated on Figure 2-8b, Proposed Improvements – Group B.

Element 1. Pedestrian/Bike Bridge North of Katella: To further improve mobility between both sides of the Santa Ana River, the project includes a non-motorized bridge dedicated to pedestrians and bicyclists. This east–west bridge would be approximately 400 feet long and 36 to 60 feet wide, with retaining walls along both banks. The bridge elevation would be approximately 174 feet, providing adequate freeboard during storm events. The concept design includes three cantilever overlooks. Upon completion, this bridge would functionally replace the existing SART river crossing at the Katella Avenue bridge for non-motorists.

Element 2. Pedestrian/Bike Bridge North of Orangewood Avenue: To further improve mobility between both sides of the Santa Ana River, the project includes a second non-motorized bridge dedicated to Chapter 2: Project Description
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pedestrians and bicyclists. This bridge would be approximately 350 feet long and 12 to 18 feet wide, located north of Orangewood Avenue, providing multiple safe connections between the riverbanks.

Element 3. Bridge Retaining Walls: Three retaining walls would support the pedestrian/bike bridge north of Katella Avenue (Group B, Element 1). Two would be located on the west bank and one on the east bank. Retaining walls are not expected to be needed for the pedestrian/bike bridge north of Orangewood Avenue (Element 2).

Group C – New Trails and Trail Improvements
There are four project elements in Group C, as described below and illustrated on Figure 2-8c, Proposed Improvements – Group C.

Element 1. West Bank Trail Connection from Katella Avenue to Anaheim Coves: The trail connection would extend from Katella Avenue to Anaheim Coves. The new trail would include three undercrossing at ultimate condition: one for the UPRR and two for Ball Road.

During the interim condition, there would be two options to cross the UPRR: one at the new at-grade crossing along the riverbank and one at the existing at-grade crossing at Phoenix Club Drive. The new interim at-grade crossing would be approximately 100 feet long and 18 feet wide. The existing at-grade crossing is approximately 380 feet to the west; therefore, using this existing at-grade crossing would require a detour from the trail, and an interim connection to this at-grade crossing would be provided. At ultimate condition, an approximately 500-foot-long UPRR undercrossing would be constructed to provide a safe, grade-separated trail crossing under the UPRR.

There is an existing paved maintenance-only Ball Road Bridge undercrossing, which would be improved as part of the trail connection for public use. Additionally, a second undercrossing could be provided by repurposing an existing box culvert under Ball Road near Phoenix Club Drive. The existing 14' x 14' box culvert is currently needed, but once the new Burris Basin overflow is constructed, it will no longer be needed by OCWD to transfer water to the former Ball Road Basin south of Ball Road. Therefore, the culvert could be repurposed as a grade-separated trail crossing under Ball Road for pedestrians and bicyclists. The Ball Road Basin is not part of the project and is planned to one day be developed as future residential use by OCVIBE.

The west bank trail system would include an approximately 750-foot-long and up to 8-foot-high retaining wall along the OC River Walk boundary and the planned River Road and a river access/kayak ramp south of Cerritos Avenue using the existing maintenance ramp.

Additionally, other improvements related to the west bank trail system could include landscaping and irrigation, separated bike and pedestrian trails, lighting, and amenities such as fitness equipment, children’s play areas, shade structures, bench seating, and drinking fountains.

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Element 2. West Bank Trail Connection from Katella Avenue to Orangewood Avenue: This trail connection would extend from Katella Avenue to Orangewood Avenue. As shown on Figure 2-5, existing SART, underpasses, and maintenance access exist between Katella Avenue and Orangewood Avenue, and the project would provide improvements to this existing trail system. It would include an undercrossing at the Metrolink/LOSSAN Corridor and a widening of the existing SR-57 underpass trail. The undercrossing would be approximately 800 feet long and 20 feet wide, while the retaining wall for the SR-57 underpass would be about 900 feet long and up to 12 feet high. About 400 feet of the existing SR-57 freeway underpass would be widened from 35 feet to about 55 feet, and a retaining wall of equal length (up to 14 feet high) would be provided. The trail would pass along the existing ARTIC station, the future Meadow Park (as part of the OCVIBE Project), and the future River Park between the project site and Angel Stadium (as part of a separate City project). Recreational facilities, including embankment seating and steps, would be provided along the trail adjacent to the future Meadow Park and River Park. Additionally, the following lists various trail-related improvements that may be included as needed; the locations of these amenities have not yet been determined:
• Grade-separated pathways
• Benches/seating
• Gathering tables
• Wayfinding/signage
• Shade structures
• Trees
• Landscaping
• Irrigation
• Lighting
• Art exhibits
• Children play areas
• Fitness stations
• Drinking fountains
Element 3. East Bank Trail Connection from Katella Avenue to Ball Road: The existing SART runs along the east bank north of Katella Avenue, and there is an existing access/maintenance underpass beneath Katella Avenue. The project would improve the existing SART to provide new access for the new pedestrian/bike bridge north of Katella Avenue, terraced overlooks and river access, and various water recreation opportunities. Retaining walls would also be provided: one adjacent to the proposed terraced overlooks and river access and another along the trail near the river access.

Additionally, other trail-related improvements as listed under Group C, Element 2, could be included as needed.

Element 4. East Bank Trail Connection from Katella Avenue to Orangewood Avenue: There is an existing maintenance access between Katella Avenue and Orangewood Avenue used by vehicles Chapter 2: Project Description
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only and fenced off for public access. The project would enhance this section of the SART and reroute the main SART line to the east bank. In areas where trail segments are expected to be used by bulldozers for maintenance, bulldozer-access pavers would be selected to minimize track damage.

Group D – Enhanced Community Recreation Amenities
There are six project elements in Group D, as described below and illustrated on Figure 2-8d, Proposed Improvements – Group D.

Elements 1 and 2. River Recreation – North and South Impoundment: Potential future recreational activities range from passive (non-contact) to active programmed recreation such as kayaking (or other forms of non-motorized boating), stand-up paddle boarding, urban beaches, and potentially swimming along the embankment or floating recreational features. These elements would also include recirculation and water feature pumps, pumps for circulation and treatment to provide the water quality necessary for swimming and other direct human contact activities, and equipment for the various active water recreation activities.

Element 3. OCVIBE Lot B Parking Lot to OC River Walk Park: This approximately 2.2-acre area is owned by OCFCD and occasionally used for river maintenance staging and access. It is currently leased to OCVIBE and is designated as a future parking lot within the OCVIBE project boundary.

Given this area’s proximity to the OC River Walk, there could be an opportunity to change its use for future park and other public use as part of the OC River Walk Project. As a potential future park/open space, the site could expand the OC River Walk project’s open areas and provide river ramp access for kayaking and other water recreation activities. Improvements would require prior approval by OCVIBE.

Element 4. Park/River Terrace – East Bank North of Katella: This area comprises approximately

10.5 acres on the east bank between Katella Avenue and Ball Road, providing opportunities for future park development with various improvements. The OCFCD owns the 8.3-acre portion between Katella Avenue and the UPRR, and the County of Orange owns the remaining 2.2 acres without any specific department within the County jurisdiction.

Element 5. Riverbed between Impoundments: The approximately 3.8-acre area of exposed riverbed created by the impoundments offers future recreational opportunities, although no specific program has been identified yet.

Element 6. Art/Education/Signage: The project would integrate art and educational features throughout the OC River Walk to enhance the visitor experience and reinforce the project's identity. Table 2-1 lists various components in this art/education/signage element, and Figure 2-8d shows their approximate locations. The quantity and specific locations of various components would be determined later. Some of the main components include but are not limited to giant iconic signage, an interactive educational component to emphasize the importance of the impoundments Chapter 2: Project Description
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for regional water resilience and groundwater recharge, decorative LED lighting and murals on the bridges and freeway underpass, shade structures, and the River Poetry Walk, which is public art concept with the poetic subject matter centered around the river and showcase the diversity of the people and communities in the region. Additionally, other trail-related improvements as listed under Group C, Element 2, could be included as needed.

Circulation and Trail System
The project would include a trail system that consists of a pedestrian-only, bike-only, and shared paths, as shown on Figure 2-10, Trail Circulation System. These three trail types would be generally designed based on the following five typical trail conditions:
• Grade-Separated Bike and Pedestrian Paths: An approximately 12-foot shared bike path grade separated next to an approximately 12-foot concrete pedestrian path. • Shared Promenade: An approximately 26-foot-wide concrete promenade. • Separated Bike and Pedestrian Path: An approximately 12-foot shared asphalt bike path separated by a planted buffer with varied width depending on available right-of-way width and an approximately 12-foot split concrete and decomposed granite pedestrian path. • Raised Cycle Path With Buffer: An approximately 10-foot cycle path with a painted buffer between a 5-foot concrete or decomposed granite pedestrian path. • Shared Mixed-Use Trail With Adjacent Soft Path: An approximately 17-foot-wide path consisting of a shared asphalt bike path adjacent to a five-foot decomposed granite pedestrian path.

Figure 2-11, Project Rendering – South of Cerritos River Access, and Figure 2-12, Project Rendering – South of SR-57 Freeway, illustrate simulated project site views of the Santa Ana River south of Katella Avenue river access looking south with ARTIC and “The Big A” sign in the background and view of the river and the enhanced recreational facilities looking north.

Off-Site Improvements
To implement the OC River Walk Conceptual Master Plan, several off-site improvements would be required outside the project boundary, including a new GWRS turnout structure and three tieins to a connection pipeline to OCSAN sewer lines, as shown on Figure 2-13, Off-Site Improvements. The GWRS turnout structure would have a 50 MGD capacity at Burris Basin and connect to the 30- to 40-inch pipeline (Group A, Element 3). The OCWD anticipates that typical daily flows would range from no flow to approximately 10 MGD. The project would require modification to the approved GWRS turnout structure to provide additional options to discharge either into the pipeline to the south impoundment pump station or directly into the river, supplying ultra-pure GWRS water for the impoundments. Two sewer tie-ins would be located within the City of Anaheim—one south of the SR-57 freeway and one north of Katella Avenue—and one in the Chapter 2: Project Description
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City of Orange at Katella Avenue. A 4- to 6-inch off-site connection pipeline from the diversion pump station north of Orangewood Avenue on the west bank would connect to the OCSAN tie-in.

The project would also require other off-site electrical utility improvements to power the pump stations and other improvements that require electricity.

2.4.1 Project Construction
The project is anticipated to take place in multiple phases over approximately 10 years. The construction is tentatively scheduled between the second quarter of 2026 and the second quarter of 2036 at the earliest. The initial phase of construction would include various elements in Groups B and C, such as construction of a bridge or various trail improvements. The initial construction is expected to take approximately 24 to 36 months.

2.5 Discretionary Actions
• Approval of the OC River Walk Conceptual Master Plan
• Certification of the EIR
• Adoption of the Mitigation Monitoring and Reporting Program • Minor update to Figure 4, Existing and Planned Bikeway Network, of the City’s Circulation Element (refer to Figure 2-14, Proposed Bikeway Network).

2.5.1 Other Agency Approvals
Under CEQA, state and local agencies (other than the lead agency) with discretionary authority over a project or aspects of a project are considered responsible agencies. Federal agencies are not responsible agencies under CEQA. The following federal, state, regional, and local agencies may have discretionary authority over the project:
• Lead agency
− Approval of Street Improvement Plans
− Issuance of grading permits
− Encroachment and access permit applications
• Federal
− U.S. Fish and Wildlife Service (USFWS) – Approval of Sections 7 and 10(a) of the federal Endangered Species Act (FESA) compliance − USACE – Approval of Section 404 Permit and Section 408 Permit, flood contingency plan review and approval
• State
− California Department of Fish and Wildlife (CDFW) – Approval of Section 1602 Permit
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− California Department of Transportation (Caltrans) – Approval of access and encroachment permits within Caltrans right-of-way (i.e., SR-57 freeway), any public artwork within Caltrans right-of-way
− State Historic Preservation Office (SHPO) – Approval of Section 106 compliance − California Public Utilities Commission – Approval of railroad undercrossings at UPRR north of Katella and at Metrolink/LOSSAN adjacent to ARTIC, possible GWRS waterline encroachment permit and access agreement. − California Department of Water Resources – Approval of groundwater management permit (if not covered by the OCWD)
− California State Water Board, Division of Drinking Water – Approval of Title 22 Reuse Permit Amendment for GWRS water, amendment to the OCWD’s existing Title 22 permit
• Regional
− RWQCB – Approval of Section 401 Water Quality Certification; Approval of NPDES Permit; Approval of amendments to OCWD’s Waste Discharge Requirements and Master Recycling Permit for the GWRS
− Southern California Regional Rail Authority – Approval of encroachment/right-of-entry and road crossings permits related to Metrolink, access and installation permitting for public artwork
− UPRR – Approval of encroachment/right-of-way entry and road crossing permit related to UPRR
− Southern California Edison – Approval of encroachment permit • Local
− City of Orange – Approval of encroachment and access permits; minor amendments to the City of Orange General Plan Circulation and Mobility Element and the Bikeways Master Plan may be necessary as improvements are undertaken.
− OCPW and OCFCD – Approval of encroachment and conditional use permits, construction and general use permits, flood contingency plan review and approval, amendment to OCWD-OCFCD agreement for maximum height of OCWD dams within the SAR, OCFCD permit for modifications to undercrossing − OCWD and OCFCD – Approval of easement for trail purposes − Orange County Parks – Approval of General Use Permit for portions of SART OCFCD’s permits for trail improvements requires review and approval by OC Parks prior to issuance as it pertains to the maintenance responsibilities identified in the County of Orange’s Memorandum of Understanding.

Amendments to existing agreements for the management of trail areas from OC Parks to the City of Anaheim may be required.

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OC River Walk Project
− OCWD – Approval of encroachment and use permits, approval of ownership and maintenance agreements, amendment to OCWD-OCFCD agreement for maximum height of OCWD dams within the SAR, modification/relocation of existing at-grade infrastructure
− OCSAN – Approval of any on and off-site sewer improvements (encroachment permits, permit to discharge dry-weather flow to sewer) − Orange County Transportation Authority – Approval of access permit Some of the above-listed permits are described in detail below.

CDFW Section 1602 Permit. The CDFW requires notification for any project or activity that will take place within or in the vicinity of a river, stream, or lake or its tributaries. Section 1602 of the California Fish and Game Code requires that any entity, including any state or local governmental agency, provide written notification to the CDFW before beginning any construction project that will (1) substantially divert or obstruct the natural flow of or change the natural flow or the bed, channel, or bank of any river, stream, or lake; (2) substantially change or use any material from a streambed, bank, or channel; or (3) deposit or dispose of debris, waste, or other material containing crumbled, flaked, or ground pavement where it can be transported into any river, stream, or lake.

RWQCB Section 401 Water Quality Certification. The State Water Resources Control Board (SWRCB) and the RWQCBs promulgate and enforce narrative and numeric water quality standards to protect water quality and to adopt and approve Water Quality Control Plans. The SWRCB and the RWQCBs also regulate discharges of harmful substances to surface waters, including wetlands, under the federal Clean Water Act (CWA) and the Porter-Cologne Water Quality Control Act (Porter-Cologne). If issuance of a Section 404 permit is required, it will be subject to Water Quality Certification by the RWQCB under the CWA Section 401.

RWQCB NPDES Permit. The CWA requires an NPDES permit for any discharge of pollutants from a point source to waters of the United States. This law and its regulations also apply to stormwater in certain circumstances. In 1987, Congress amended the CWA to require implementation, in two phases, of a comprehensive national program for addressing stormwater discharges. Phase I requires NPDES permits for stormwater discharge from many priority sources, including medium and large municipal separate storm sewer systems (MS4s), and several categories of industrial activity, including construction activity that disturbs 1 or more acres of land. Phase II of the stormwater program requires permits for stormwater discharges from certain MS4s serving a population of less than 100,000.

SHPO Section 106 Compliance. For projects with federal funding or requiring federal approvals, Section 106 of the National Historic Preservation Act of 1966, as amended by U.S. Code, Title 16, Section 470 et seq., and the Code of Federal Regulations, Title 36, Section 800, includes provisions for protection of significant archaeological and historical resources. Procedures for dealing with previously unsuspected cultural resources discovered during construction are identified in the Chapter 2: Project Description
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Code of Federal Regulations, Title 36, Section 800 (for implementing Section 106 processes). The administering agency is SHPO and the federal lead agency. Section 106 compliance is required to obtain a Section 404 permit from the USACE.

USFWS Sections 7 and 10(a) of FESA. Sections 7 and 10(a) of FESA regulate actions that could jeopardize endangered or threatened species. Section 7 describes a process of federal interagency consultation for use when federal actions may adversely affect listed species. In this case, take can be authorized by a letter of biological opinion issued by the USFWS for nonmarine-related listed species issues. A Section 7 consultation (formal or informal) is required when there is a nexus between endangered species’ use of a site and impacts to USACE jurisdictional areas or to other areas for which a federal action is required. Section 7 consultations with the USFWS are initiated by the federal agency that will be taking a federal action on the project (e.g., USACE initiates the consultation if it is reviewing a Section 404 permit application that results in impacts to occupied listed species habitat).

Section 10(a) allows issuance of permits for incidental take of endangered or threatened species with preparation of a Habitat Conservation Plan when there is no federal nexus. The term “incidental” applies if the taking of a listed species is incidental to, and not the purpose of, an otherwise lawful activity. A Habitat Conservation Plan demonstrating how the taking would be minimized and how steps taken would ensure the species’ survival must be submitted for issuance of Section 10(a) permits.

USACE Section 404 Permit. The USACE regulates the nation’s waterways and wetlands and is responsible for implementing and enforcing Section 404 of the CWA. The USACE regulations require that any activity that discharges fill material or requires excavation in waters of the United States, including wetlands, must obtain a Section 404 permit.

USACE Section 408 Permit. This permit would allow the City of Anaheim to alter a USACE civil works project, various improvements in the Santa Ana River.

California Code of Regulations, Title 22, Reuse Permit. This code title refers to state guidelines for how treated and recycled water is discharged and used. It would allow the project to use treated recycled water to replenish groundwater aquifers, following the regulations outlined in Title 22 regarding water reuse and quality standards; essentially, it is a permit to use recycled water for indirect potable reuse through groundwater recharge.

The project would also require temporary construction easements to be identified and secured from the following stakeholders for the duration of the project:
• OCWD
• OCFCD
• Orange County Parks
• Orange County Transportation Authority
• California Public Utilities Commission
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• Southern California Edison
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Source: Pacific Advanced Civil Engineering, Inc. (PACE).

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Orange County Flood Control District
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Firebird Real Estate Holdings LLC Anaheim Orange
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ARTIC STATION

COLLINS CHANNEL

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
Chapter 2: Project Description
Final EIR No. 357 2-36 November 2025
OC River Walk Project
This page intentionally left blank.

Source: OC River Walk Vision Plan 2024.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 400 800 Figure 2-4d
Existing Project Site Views
OC River Walk
N
NCEPTUAL MASTER PLAN 202412

SANTA ANA RIVER
12' 15' 12' 12' 33'
SART

BUFFER BUFFER FUTURE DEVELOPMENT
PATH

MAINTENANCE
PATH

IMPROVEMENT AREA
35-150'

IMPROVEMENT AREA
12'

IMPROVEMENT AREA

IMPROVEMENT AREA
REACH 4

ANGEL STADIUM
57 FREEWAY

ORANGEWOOD AVE

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
Chapter 2: Project Description
Final EIR No. 357 2-38 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering, Inc. (PACE), C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-5
Existing Condition - Surface
OC River Walk
Feet
N
0 600 1200Anaheim OrangeKatella Ave
Ball Rd
Orangewood Ave
Eckhoff St
Collins Ave
Main St
Taft Ave
UPRR
Metrolink RR
57 FWY
Douglas Rd
Phoenix Club Dr
Auto Center Dr
Cerritos Ave
Existing Access Ramp
Existing Access/Maintenance Road
Existing Access/Maintenance Roads Underpass
Existing Santa Ana River Trail (SART)
Existing Santa Ana River Trail Underpass
Existing Anaheim Coves Trail
Existing Drop Structure
OC River Walk Study Area
City Boundary
Angel
Stadium
ARTIC Stadium
Promenade
Honda
Center
Arena
Corporate
Center Collins Channel
Ex. Anaheim Coves Trail
SCE Overhead Powerline Easement
Islands
Golf
Center
Burris
Basin
OC Sheriff's
Dept
OC Public
Works
Santa Ana River
Santa Ana River
Kinder Morgan
Orange Terminal
County of
Orange
Ex.

Culvert
Chapter 2: Project Description
Final EIR No. 357 2-40 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering, Inc. (PACE).

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Anaheim Orange
Katella Ave
Ball Rd
Orangewood Ave
Eckhoff St
Collins Ave
Main St
Taft Ave
UPRR
Metrolink RR
57 FWY
Douglas Rd
Phoenix Club Dr
Auto Center Dr
Cerritos Ave
Collins Channel
Storm Drain
Abandoned Storm Drain
GWRS Pipeline
SARI Sewer
OCSD Trunk Sewer
OC River Walk Study Area
City Boundary
Angel
Stadium
ARTIC Stadium
Promenade
Honda
Center
Arena
Corporate
Center Collins Channel
Ex. Anaheim Coves Trail
SCE Overhead Powerline Easement
Islands
Golf
Center
Burris
Basin
Kinder Morgan
Orange Terminal
OC Sheriff's
Dept
OC Public
Works
Santa Ana River
Santa Ana River
County of
Orange
Ex.

Culvert
Figure 2-6
Existing Condition - Underground
OC River Walk
Feet
N
0 600 1200
Chapter 2: Project Description
Final EIR No. 357 2-42 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering, Inc. (PACE).

Katella Ave
Ball Rd
Orangewood Ave
Eckhoff St
Collins Ave
Main St
Taft Ave
UPRR
Metrolink RR
57 FWY
Douglas Rd
Phoenix Club Dr
Auto Center Dr
Cerritos Ave Anaheim Orange
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
CH
SD
SD
SD
SD
SD
SD
Storm Drain
Outlet
Existing Access
Ramp
Proposed Access
Ramp
Proposed
Impoundment
Proposed
Inflatable Rubber
Dam
OC River Walk
Trail
Improvements
Proposed Ped./
Bike Bridge
Proposed RR
Undercrossings
Proposed Kayak
Access (Maintain
Existing OCFCD
Access)
Existing
Undercrossing
Existing Storm
Drain
Existing Drop
Structure
City Boundary
Angel
Stadium
ARTIC Stadium
Promenade
Honda
Center
Arena
Corporate
Center Collins Channel
Islands
Golf
Center
Burris
Basin
OC Sheriff's
Dept
OC Public
Works
Santa Ana River
Santa Ana River
Kinder Morgan
Orange Terminal
SD
C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 600 1200 Figure 2-7
Proposed Impoundments and Trail Improvements
OC River Walk
N
Chapter 2: Project Description
Final EIR No. 357 2-44 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering, Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8
Overall Project Elements
OC River Walk
N
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B (F) Market & Office (F)
Concert
Hall
(F)
The Steps (F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C (F)
Hotel (E)
Parking Deck A (F)
Honda
Center
(Existing)

ARTIC (E)
Existing Drop Structure
Existing Drop Structure
Angel Stadium (E)

STADIUM PROMENADE

KINDER MORGAN ORANGE TERMINAL

TAFT / MAIN CORPORATE CENTER
KATELLA COMMERCE CENTER Office (E)
Hotel (E) Appts. (E)
Theater & Retail (E)
Main St
Main St
Katella Ave
Katella Ave
57 Fwy
57 Fwy
57 Fwy

COUNTY OF ORANGE

ISLANDS GOLF

CENTER (E)

BURRIS BASIN (E)
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout
PPSS
Feet
0 600 1200
Chapter 2: Project Description
Final EIR No. 357 2-46 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8a
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B (F) Market & Office (F)
Concert
Hall
(F)
The Steps (F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C (F)
Hotel (E)
Parking Deck A (F)
Honda
Center
(Existing)

ARTIC (E)
Existing Drop Structure
Existing Drop Structure
Angel Stadium (E)

STADIUM PROMENADE

KINDER MORGAN ORANGE TERMINAL

COUNTY OF ORANGE

OC PUBLIC WORKS
OC SHERIFF'S DEPT.
(E)
City of Anaheim - Future Park
Future Open Space Meadow Park
Ex. Anaheim Coves Trail
Future River Road Stanley Cup Way
Cerritos Ave
Ball Rd
Katella Ave
Futurue
Neighborhood
Park
Future Development
1d,e
6b
2 3
6a
1a, b
1g,h,i
6b
3 3
4 5e,g
5h
5f,g
5a,b 5c
5a,b
5a,b
5c
5a,b
5a,b
5e,g 5e,g,h
5e,g,h
5e,g
5e,g
5a,b
1f
1c
6a
5a,b
6b 5e,g
6a
6b
6a
SP

ISLANDS GOLF

CENTER (E)

BURRIS BASIN (E)
Metrolink RR
(MEADOW PARK)

1. Project element encompasses entire project area or is not specifically located at this time Note: All project locations are approximate
1a North Impoundment and Inflatable Rubber Dam 5a Anaheim - Storm Drain Outlets w/ Flap Gates 1b North Impoundment - Rubber Dam Concrete Foundation 5b Anaheim - Diversion Manholes 1c North Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5c Anaheim - Diversion Pump Stations 1d South Impoundment 5d Anaheim - Storm Drain Diversion Pipe to Sewer 1e South Impoundment - Rubber Dam Concrete Foundation 5e Orange - Storm Drain Outlets w/ Flap Gates 1f South Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5f Orange - In-Channel Diversion Structure at Collins Channel 1g Collins Channel - Inflatable Rubber Dam 5g Orange - Diversion Manholes 1h Collins Channel - Rubber Dam Concrete Foundation 5h Orange - Diversion Pump Stations 1i Collins Channel - Rubber Dam Air Compressor and Controls 5i Orange - Storm Drain Diversion Pipe to Sewer 5j Wet Weather Storm Drain Diversion to Impoundments*
6a North Impoundment Embankment
6b South Impoundment Embankment

2. Impoundment Evacuation Pumps

3. Pipeline from Pump Station to GWRS Turnout - N. of Orangewood to Burris Basin

4. GWRS Turnout - Concrete flow control structure with dechlorination facilities. Located at south end of Burris Basin - Offsite Project Element

GROUP A - IMPOUNDMENTS, EMBANKMENTS, & STORM DRAIN DIVERSIONS

1. Impoundments 5. Storm Drain Diversions (Dry Weather Flow)

6. River Embankments
1a North Impoundment and Inflatable Rubber Dam 5a Anaheim - Storm Drain Outlets w/ Flap Gates 1b North Impoundment - Rubber Dam Concrete Foundation 5b Anaheim - Diversion Manholes 1c North Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5c Anaheim - Diversion Pump Stations 1d South Impoundment 5d Anaheim - Storm Drain Diversion Pipe to Sewer 1e South Impoundment - Rubber Dam Concrete Foundation 5e Orange - Storm Drain Outlets w/ Flap Gates 1f South Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5f Orange - In-Channel Diversion Structure at Collins Channel 1g Collins Channel - Inflatable Rubber Dam 5g Orange - Diversion Manholes 1h Collins Channel - Rubber Dam Concrete Foundation 5h Orange - Diversion Pump Stations 1i Collins Channel - Rubber Dam Air Compressor and Controls 5i Orange - Storm Drain Diversion Pipe to Sewer 5j Wet Weather Storm Drain Diversion to Impoundments¹
6a North Impoundment Embankment
6b South Impoundment Embankment

2. Impoundment Evacuation Pumps

3. Pipeline from Pump Station to GWRS Turnout - N. of Orangewood to Burris Basin

4. GWRS Turnout - Concrete flow control structure with dechlorination facilities. Located at south end of Burris Basin - Offsite Project Element

GROUP A - IMPOUNDMENTS, EMBANKMENTS, & STORM DRAIN DIVERSIONS

1. Impoundments 5. Storm Drain Diversions (Dry Weather Flow)

6. River Embankments
and Inflatable Rubber Dam
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout PSSP
Proposed Improvements - Group A
OC River Walk
Feet
N
0 500 1000
Chapter 2: Project Description
Final EIR No. 357 2-48 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8b
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B (F) Market & Office (F)
Concert
Hall
(F)
The Steps (F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C (F)
Hotel (E)
Parking Deck A (F)
Honda
Center
(Existing)

ARTIC (E)
Existing Drop Structure
Existing Drop Structure
Angel Stadium (E)

STADIUM PROMENADE

KINDER MORGAN ORANGE TERMINAL

COUNTY OF ORANGE

OC PUBLIC WORKS
OC SHERIFF'S DEPT.
(E)
City of Anaheim - Future Park
Future Open Space Meadow Park
Ex. Anaheim Coves Trail
Future River Road Stanley Cup Way
Cerritos Ave
Katella Ave
Futurue
Neighborhood
Park
Future Development
2 1
3a
3b
3c
Ball Rd
SP

ISLANDS GOLF

CENTER (E)

BURRIS BASIN (E)
(MEADOW PARK)
Metrolink RR
Note: All project locations are approximate
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout PSSP
3a New Ped./Bike Bridge N. of Katella West Bank Retaining Wall #1 3b New Ped./Bike Bridge N. of Katella West Bank Retaining Wall #2 3c New Ped./Bike Bridge N. of Katella East Bank Retaining Wall #3

2. Ped./Bike Bridge N. of Orangewood

3. Bridge Retaining Walls

GROUP B - NEW PEDESTRIAN/BIKE BRIDGES

1. Ped./Bike Bridge N. of Katella
Proposed Improvements - Group B
OC River Walk
Feet
N
0 500 1000
Chapter 2: Project Description
Final EIR No. 357 2-50 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8c
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B (F) Market & Office (F)
Concert
Hall
(F)
The Steps (F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C (F)
Hotel (E)
Parking Deck A (F)
Honda
Center
(Existing)

ARTIC (E)
Existing Drop Structure
Existing Drop Structure
Angel Stadium (E)

STADIUM PROMENADE

KINDER MORGAN ORANGE TERMINAL

COUNTY OF ORANGE

ISLANDS GOLF

CENTER (E)

BURRIS BASIN (E)
(MEADOW PARK)
Metrolink RR

1. Project element encompasses entire project area or is not specifically located at this time Note: All project locations are approximate
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout PSSP
1g River Access/Kayak Ramp South of Cerritos - Existing Ramp 1h Interim UPRR Crossing at Phoenix Club Dr. - Existing RR Crossing & New Interim Connection Trail 1i Replace Access Road Only (For New Ped./Bike Bridge N. of Katella) 2a Embankment Seating and Steps
2b Metrolink RR Undercrossing - Existing Undercrossing
2c Metrolink Underpass Retaining Wall
2d River Walk South Embankment Seating and Steps
2e SR-57 Underpass Trail Widening
2f SR-57 Retaining Wall

2. Trail West Bank - Katella to Orangewood
1a UPRR - Undercrossing - New Undercrossing 3a Replace Access Road Only (For New Ped./Bike Bridge N. of Katella) 1b UPRR Undercrossing Retaining Wall 3b Improve Trail w/ Terrace & Community Access 1c UPRR - At Grade Crossing - Existing Maintenance Access 3c East Bank Park/River Terrace Retaining Wall #1 1d OC River Walk & River Road Retaining Wall 3d City of Orange Water Recreation Opportunity ¹ 1e Ball Rd. Culvert Undercrossing - Existing 14x14 RCB 3e East Bank Park/River Terrace Retaining Wall #2 1f Ball Rd. Bridge Undercrossing w/ City & County & OCWD - Existing Maintenance Access

GROUP C - NEW TRAILS & TRAIL IMPROVEMENTS

1. Trail West Bank - Katella to Anaheim Coves (6,400 LF total, 18' typ. width) 3. Trail East Bank Katella to Ball Rd.

4. Trail East Bank Katella to Orangewood: SART - Main Line Reroute to East Bank of River Proposed Improvements - Group C
OC River Walk
Feet
N
0 500 1000
Chapter 2: Project Description
Final EIR No. 357 2-52 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8d
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B (F) Market & Office (F)
Concert
Hall
(F)
The Steps (F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C (F)
Hotel (E)
Parking Deck A (F)
Honda
Center
(Existing)

ARTIC (E)
Existing Drop Structure
Existing Drop Structure
Angel Stadium (E)

STADIUM PROMENADE

KINDER MORGAN ORANGE TERMINAL

COUNTY OF ORANGE

ISLANDS GOLF

CENTER (E)

BURRIS BASIN (E)
(MEADOW PARK)
Metrolink RR

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout PSSP
4a East Bank (City of Orange) Katella to UPRR
4b UPRR to Ball Rd.

3. OCVIBE Lot B Parking Lot, Potential Future OC River Walk Park

4. Park / River Terrace: East Bank North of Katella
1a Kayaking & Water Recreation Activities
1b Swimming / Wading Recreational Opportunity 6a Iconic Signage ¹ 1c Recirculation and Water Feature Pumps ¹ 6b Bridge Mural and Lighting 1d Water Feature Elements ¹ 6c Mosaic & Art Installations 1e Swimming Water Quality Pumps and Treatment ¹ 6d Reflective Shade Canopies 6e Zen Zone / Wildflower Space ¹
2a Kayaking & Water Recreation Activities 6f River Poetry Walk 2b Under SR-57: Lighting & Other Amenities 6g Interactive Educational Component 2c Recirculation and Water Feature Pumps ¹ 6h Wayfinding Signage ¹ 2d Water Feature Elements ¹ 6i Conceptual Locations for Art/Signage Opportunities ¹

6. Art / Education / Signage (Conceptual Locations)

2. River Recreation - South Impoundment

GROUP D - ENHANCED COMMUNITY RECREATION AMENITIES

1. River Recreation - North Impoundment 5. Riverbed Recreational Areas (Future Recreational Opportunities) Proposed Improvements - Group D
OC River Walk
Feet
N
0 500 1000
Chapter 2: Project Description
Final EIR No. 357 2-54 November 2025
OC River Walk Project
This page intentionally left blank.

Source: Pacific Advanced Civil Engineering, Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Top of West Bank
Top of East Bank
190yr Design Flood
US Impoundment
DS Impoundment
River Bed
0 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000 2,200 2,400 2,600 2,800 3,000 3,200 3,400 3,600 3,800 4,000 4,200 4,400 4,600 4,800 5,000 5,200 5,400 5,600 5,800 130
135
140
145
150
155
160
165
170
175
180
Proposed Ped./Bike Bridge
Existing Drop Structure
Proposed Inflatable Rubber Dam
Proposed Impoundment
Existing Access Ramp
Proposed Access Ramp
Ex. Drop
Structure
7ft
Rubber Dam
Impoundment
10ft
US Rubber Dam
Impoundment
8ft
57 FWY
Orangewood Ave
Bridge
Metro RR Bridge:

Katella Ave
Bridge
Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community WSEL: 154 ft
Volume: 110 AF
WSEL: 145 ft
Volume: 90 AF
Proposed
Ped./Bike
Bridge
Proposed
Ped./Bike
Bridge
North Impoundment:

Length: 3,000 ft, Area: 22ac
South Impoundment:

Length: 1,700 ft, Area: 11.5 ac
Santa Ana River
Collins Channel
MN
Arena
Corporate
Center
Honda
Center
Stadium
Promenade
Angels
Stadium
ARTIC
Douglas Rd
Katella Ave
Collins Ave
Eckhoff St
Orangewood Ave
Feet
0 500 1000 Figure 2-9
Rubber Impoundments
OC River Walk
N
Chapter 2: Project Description
Final EIR No. 357 2-56 November 2025
OC River Walk Project
This page intentionally left blank.

Source: OC River Walk Vision Plan, 2024.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 400 800 Figure 2-10
Trail Circulation System
OC River Walk
N
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024
I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
39 CIRCULATION AND TRAIL TYPES
Creating an accessible, safe, and multi-modal travel corridor involves giving all people better access to convenient and continuous pedestrian paths and bike trails. Whether by bike, scooter, by foot, or public transit, the OC River Walk reimagines the area to deliver a safer and more connected corridor for people to use. Through careful analysis of the existing embankment widths and right-of-way widths, the project deploys five typical trail types across the site. The trail types are outlined below.
12-foot shared asphalt bike path separated by a planted buffer (width varies depending on available ROW width) and 12-foot split concrete and decomposed granite pedestrian path. Image:

Separated paths | Source: Pinterest
Gracious 26-foot width concrete promenade. Image: Bow River Walk | Source: Stantec
12-foot shared bike path grade separated next to a 12-foot concrete pedestrian path. Image: Rossall Seawall & Coastal Defence Scheme | Source: Visit Fylde Coast

KATELLA AVE

ARTIC RAIL ROAD

ORANGEWOOD AVE

PROPERTY LINE

PROPERTY LINE
57 COLLINS CHANNEL

RIVER ROAD

GRADE SEPARATED BIKE AND PEDESTRIAN PATHS SHARED PROMENADE SEPARATED BIKE AND PEDESTRIAN PATH

TYPICAL TRAIL CONDITIONS
UNDERCROSSING (NEW) UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)

CONNECTION TO ARTIC
SHARED PEDESTRIAN + BIKE BRIDGE
12’
12’ 12’
12’
26’

SHARED PROMENADE

SEPARATED BIKE AND

PEDESTRIAN PATH

GRADE SEPARATED BIKE

AND PEDESTRIAN PATH
10-foot cycle track with a planted b
concrete pedestrian path. Image: H
Source: Flickr

STANLEY CUP
WAY

RAISED CYCLE TRACK WITH BUFF
SHARED PEDESTRIAN + BIKE BRI

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH
5’ 12’

ARTIC STATION
(EXISTING)

HONDA CENTER
(EXISTING)
FUTURE

ADJACENT

OPEN SPACE

FUTURE ADJACENT OPEN SPACE

BUILDING
(EXISTING)

KATELLA AVE

PROPERTY LINE

RIVER ROAD

PEDESTRIAN PATH
UNDERCROSSING (EX.)
NDERCROSSING (EX.)

STANLEY CUP
WAY

UNION PACIFIC RAILROAD

BALL ROAD
SHARED

CIRCULATION LEGEND

PEDESTRIAN ONLY

BIKE ONLY
50 100 200
FUTURE

DEVELOPMENT

RAISED CYCLE TRACK WITH BUFFER SHARED MIXED USE TRAIL W/ ADJACENT SOFT PATH

UNDERCROSSING (NEW)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
SHARED PEDESTRIAN + BIKE BRIDGE

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

RAISED CYCLE

TRACK WITH BUFFER
5’ 12’
5’ 12’
10’ 5’

HONDA CENTER
(EXISTING)
FUTURE

ADJACENT

PEN SPACE

BUILDING
(EXISTING)

MATCHLINE

MATCHLINE
OC RIVER WALK CONCEPTUAL MASTER PLAN 202439
parated by a planted buffer
le ROW width) and 12-foot
anite pedestrian path. Image:
st

PROPERTY LINE
NE

RIVER ROAD

AN PATH
UNDERCROSSING (EX.)
NG (EX.)
10-foot cycle track with a planted buffer between a five-foot concrete pedestrian path. Image: Hudson River Bike Path | Source: Flickr
17-foot wide, with a shared asphalt bike path and a five-foot decomposed granite pedestrian path adjacent. Image: Anaheim Coves Trail | Source: Organic-Lock
SHARED

CIRCULATION LEGEND

PEDESTRIAN ONLY

BIKE ONLY
50 100 20

RAISED CYCLE TRACK WITH BUFFER SHARED MIXED USE TRAIL W/ ADJACENT SOFT PATH

UNDERCROSSING (NEW)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
SHARED PEDESTRIAN + BIKE BRIDGE
5’ 12’
Chapter 2: Project Description
Final EIR No. 357 2-58 November 2025
OC River Walk Project
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Source: OC River Walk Conceptual Master Plan, 202

5. C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 400 800 Figure 2-11
Project Rendering - South of Cerritos River Access
OC River Walk
N
Chapter 2: Project Description
Final EIR No. 357 2-60 November 2025
OC River Walk Project
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Source: PACE Advanced Water Enginerring 2024.

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Source: Pacific Advanced Civil Engineering, Inc. (PACE), 2025.

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Source: PACE Advanced Water Engineering 2025.

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Chapter 3: Environmental Setting
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Chapter 3 Environmental Setting
This chapter provides a “description of the physical environmental conditions in the vicinity of the project” (CEQA Guidelines, Section 15125[a]), pursuant to provisions of the California Environmental Quality Act (CEQA) and the CEQA Guidelines. The environmental setting provides the baseline physical conditions from which the lead agency will determine the significance of environmental impacts resulting from the project.

3.1 Regional Environmental Setting

3.1.1 Regional Location
The project site is located along the Santa Ana River corridor, generally between Orangewood Avenue and the existing Anaheim Coves at Burris Basin. The project site is primarily located within the City of Orange, and partially located within the City of Anaheim, in Orange County, California.

The City of Orange and the City of Anaheim are in the northern Orange County, surrounded by the cities of Placentia, Fullerton, Garden Grove, Tustin, Santa Ana, Stanton, Cypress, and Buena Park.

The project site crosses State Route 57 and is located approximately 0.6 miles north of Interstate (I)

5. The location of the project site in a regional context is shown on Figure 2-1, Regional Location, in this Draft Environmental Impact Report (EIR) Chapter 2, Project Description.

3.1.2 Regional Planning Considerations

3.1.2.1 SCAG Regional Transportation Plan/Sustainable Communities Strategy The Southern California Association of Governments (SCAG) is a council of governments representing six counties—Imperial, Los Angeles, Orange, Riverside, San Bernardino, and Ventura counties—191 cities, and more than 19 million residents. SCAG is the nation’s largest metropolitan planning organization, with jurisdiction over 38,000 square miles. SCAG is a regional planning agency and a forum for addressing regional issues concerning transportation, the economy, community development, and the environment. SCAG is also the regional clearinghouse for projects requiring environmental documentation under federal and state law. In this role, SCAG reviews proposed development and infrastructure projects to analyze their impacts on regional planning programs.

The 2024–2050 Regional Transportation Plan/Sustainable Communities Strategy, “Connect SoCal 2024,” was adopted in April 2024. Connect SoCal 2024 embodies a collective vision for the region’s future and is developed with input from local governments, county transportation commissions, Tribal governments, nonprofit organizations, businesses, and local stakeholders in the member counties. Connect SoCal 2024 is a long-range visioning plan that balances future mobility and housing needs with economic, environmental and public health goals. It builds upon and expands land use and transportation strategies established over several planning cycles to increase mobility options and achieve a more sustainable growth pattern. It charts a path toward a Chapter 3: Environmental Setting
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more mobile, sustainable, and prosperous region by making connections between transportation networks, between planning strategies, and between the people whose collaboration can improve the quality of life for residents of southern Californians. To achieve the plan’s vision, elements are organized within the pillars of Mobility, Communities, Environment and Economy. Connect SoCal 2024 allocates $751 billion for transportation projects, including over 2,000 local transportation projects through 2050, such as highway and street improvements, bicycle and pedestrian pathways, railroad grade separations, new transit hubs, and replacement bridges. In addition, Connect SoCal 2024 is supported by a combination of transportation and land use strategies that outline how the region can achieve California’s greenhouse gas (GHG) emissions reduction goals and federal Clean Air Act requirements. The plan also strives to achieve broader regional objectives, such as the preservation of natural lands, improvement of public health, increased roadway safety, improvement of access to jobs and educational resources, support for the region’s vital goods movement industries, and more efficient use of resources.

The Sustainable Communities Strategy outlines a development pattern for the region, which, when integrated with the transportation network and other transportation measures and policies, would reduce GHG emissions from transportation (excluding goods movement). The Sustainable Communities Strategy is meant to provide growth strategies that will achieve the regional GHG emissions reduction targets identified by the California Air Resources Board. However, the Sustainable Communities Strategy does not require that local general plans, specific plans, or zoning be consistent with the Sustainable Communities Strategy; instead, it provides incentives to governments and developers for consistency.

3.1.2.2 South Coast Air Quality Management District
The Cities of Orange and Anaheim are in the South Coast Air Basin (SCAB), which is managed by the South Coast Air Quality Management District (SCAQMD). Pollutants emitted into the ambient air by stationary and mobile sources are regulated by federal and state law and standards are detailed in the SCAB Air Quality Management Plan (AQMP). In December 2022, the SCAQMD Governing Board adopted the 2022 AQMP. The 2022 AQMP is focused on attaining the 2015 8-hour ozone standard (70 parts per billion) for the SCAB and Coachella Valley. The 2022 AQMP builds upon measures already in place from previous AQMPs. It also includes a variety of additional strategies such as regulation, accelerated deployment of available cleaner technologies (e.g., zero emission technologies, when cost-effective and feasible, and low NOx technologies in other applications), best management practices, co-benefits from existing programs (e.g., climate and energy efficiency), incentives, and other federal Clean Air Act measures to achieve the 2015 8-hour ozone standard. The 2022 AQMP was approved and adopted by the California Air Resources Board on January 26, 2023. Air basins are classified as attainment/non-attainment areas for particular pollutants depending on if they meet ambient air quality standards for that pollutant. The U.S.

Environmental Protection Agency classifies the SCAQMD as in attainment for the federal carbon Chapter 3: Environmental Setting
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monoxide (CO), nitrogen dioxide (NO2), lead, respirable particulate matter (PM10), and sulfur dioxide (SO2)standards. It is unclassifiable for PM10 with respect to federal air quality standards.

The SCAQMD is classified as in non-attainment for the ozone (O3) standard, PM10, and fine particulate matter (PM2.5) standards. The project’s consistency with the applicable ambient air quality standards is discussed in Section 4.1, Air Quality.

3.1.2.3 Greenhouse Gas Emissions Reduction Legislation
Current State of California guidance and goals for reductions in GHG emissions are generally embodied in Executive Order S-03-05; Assembly Bill (AB) 32, AB 1279; and Senate Bill 375 (SB 375).

Executive Order S-03-05, signed June 1, 2005, set the following GHG reduction targets for the State of California:
• 2000 levels by 2010
• 1990 levels by 2020
• 80 percent below 1990 levels by 2050
AB 32 was passed by the state legislature on August 31, 2006, to place the state on a course toward reducing itscontribution of GHG emissions. It directs the California Air Resources Board to ensure that statewide GHG emissions are reduced to at least 40 percent below the statewide GHG emissions limit (levels than occurred in 1990) no later than December 31, 2030. AB 1279, enacted in September 2022, updates the goals of AB 32. The bill established a statewide goal to achieve net-zero GHG emissions by 2045 and achieve and maintain net-negative GHG emissions thereafter. Additionally, the bill established a specific target for statewide anthropogenic GHG emissions to be reduced to at least 85 percent below the 1990 levels by 2045. The 2022 Scoping Plan states that the SB 32 2030 reduction target remains a critical step to achieving the AB 1279 target. Additionally, the Scoping Plan acknowledges that new technologies and statewide policies would be required to achieve the AB 1279 target beyond 2030, such as increased emissions reduction standards and increased use of zero-emissions vehicles. As such, a goal of 85 percent reduction from 1990 levels or net-zero GHG emissions is not prescribed as a local target or threshold. The 2030 interim target remains an appropriate threshold for local agencies to achieve a fair share reduction toward statewide emissions reduction goals. As such, the City of Anaheim and other lead agencies throughout the basin continue to apply the SCAQMD interim thresholds.

SB 375 was adopted in 2008 and provides a new planning process that coordinates land use planning, Regional Transportation Plans, and funding priorities to help California meet the GHG reduction goals established in AB 32. The project’s ability to meet these regional GHG emissions reduction target goals is analyzed in Section 4.5, Greenhouse Gas Emissions.

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3.1.2.4 Santa Ana River Basin Plan Water Quality Control Board The project site is under the jurisdiction of the Santa Ana Regional Water Quality Control Board (RWQCB). The Basin Plan, prepared by the Santa Ana RWQCB, establishes water quality standards for the ground and surface waters of the Santa Ana region and includes an implementation plan describing the actions by the Santa Ana RWQCB and others that are necessary to achieve and maintain the water quality standards. The RWQCB regulates waste discharges to minimize and control their effects on the quality of the region’s ground and surface water. The Water Quality Control Plan for the Santa Ana River Basin was adopted in March 1994, and the most recent comprehensive updates to the plan was adopted in February 2016. Since then, the RWCQB adopted several amendments to address specific water quality issues.

Santa Ana RWQCB implements the National Pollutant Discharge Elimination System permit for the Santa Ana area (including southern Orange County). Under the National Pollutant Discharge Elimination System permit, a requirement under the Clean Water Act, each jurisdiction must implement measures to reduce urban runoff during all phases of land use development starting with planning, during construction, and after completion of the development. The Santa Ana RWQCB has issued three Municipal Separate Stormwater Sewer System (MS4) permits to the three counties—Orange, Riverside, and San Bernardino—and all the incorporated cities within the jurisdiction of this RWQCB. The Santa Ana RWQCB MS4 Storm Water Permit, Order No. R8- 2009-0030, National Pollutant Discharge Elimination System Permit No. CAS618030, as amended by Order No. R8-2010-0062, is currently in effect, and specifies waste discharge requirements for the County of Orange, the incorporated cities of Orange County, and the Orange County Flood Control District within the Santa Ana region. In March 2024, the Santa Ana RWQCB has released a draft Santa Ana Regional MS4 Permit for public review and comment.

The draft Santa Ana Regional MS4 Permit is the first of its kind in the Santa Ana region, where each county previously maintained individual, county-wide permits. The permit combines three existing Phase I MS4 permits for north Orange, western Riverside, and western San Bernardino counties into a single regional permit encompassing the Santa Ana River Watershed area. Santa Ana RWQCB is currently reviewing the comments received during the public review period of the draft Santa Ana Regional MS4 Permit, and the final adoption date has not been announced.

3.2 Local Environmental Setting

3.2.1 Project Location
The project site is located along the Santa Ana River corridor, generally between Orangewood Avenue and the existing Anaheim Coves at Burris Basin. It generally encompasses approximately a 2-mile stretch of the Santa Ana River, covering approximately 111 acres. It is approximately 15 miles upstream from the Pacific Ocean and adjacent to Angel Stadium, Anaheim Regional Transportation Intermodal Center (ARTIC), the Honda Center, and the Arena Corporate Center Chapter 3: Environmental Setting
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(ACC) buildings on the west side of the Santa Ana River in the City of Anaheim. The ARTIC, the Honda Center, and the ACC buildings are all part of the OCVIBE Master Site Plan Project (OCVIBE Project). On the east side of the Santa Ana River, in the City of Orange, the project is near the Sandra Hutchens Regional Law Enforcement Training Center (a facility that includes a combat shooting range), the Orange County Public Works offices, the Stadium Promenade shopping mall, the Extended Stay America – Orange, and the Kinder Morgan Orange Terminal.

The project site’s regional setting is shown on Figure 2-1, while a closer view of the site and the surrounding local vicinity is shown on Figure 2-2, Local Vicinity. The project is primarily located in the City of Orange and partially located in the City of Anaheim, with many different landowners and jurisdictional bodies. Figure 2-3, Project Site and Adjacent Ownerships, shows the ownership of the project site and adjacent properties.

3.2.2 General Plan and Zoning
The project site is currently designated as Open Space (OS) and zoned Recreation Open Space (RO) for the portions in the City of Orange; and designated Open Space and zoned Transition, Public Recreational for the portions in the City of Anaheim.

3.2.3 Public Services and Utilities
The project site is surrounded by existing urban development with existing public services and utilities.The following service providers provide utilities and services to the project site. • Water – Anaheim Public Utilities and City of Orange Water Division • Wastewater – Anaheim Public Works (City of Anaheim) and Orange Public Works (City of Orange)
• Storm Water – Orange County Flood Control District
• Solid Waste – Republic Services in contract with the City of Anaheim and CR&R in contract with the City of Orange
• Electricity – Anaheim Public Utilities (City of Anaheim) and Southern California Edison (City of Orange)
• Natural Gas – Southern California Gas Company
• Police – Anaheim Police Department and Orange Police Department • Fire – Anaheim Fire & Rescue and Orange City Fire Department • School – The project site is within the SAR corridor and will not require any school services

3.3 Assumptions Regarding Cumulative Impacts
CEQA requires that EIRs discuss cumulative impacts in addition to project impacts. In accordance with CEQA, the discussion of cumulative impacts must reflect the severity of the impacts and the likelihood of their occurrence; however, the discussion need not be as detailed Chapter 3: Environmental Setting
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as the discussion of environmental impacts attributable to the project alone. Further, the discussion is guided by the standards of practicality and reasonableness. According to Section 15355 of the CEQA Guidelines, “cumulative impacts” are defined as follows:

Two or more individual effects which, when considered together, are considerable or which compound or increase other environmental impacts. (a) The individual effects may be changes resulting from a single project or a number of separate projects.
(b) The cumulative impact from several projects is the change in the environment, which results from the incremental impact of the project when added to other closely related past, present, and reasonably foreseeable probable future projects. Cumulative impacts can result from individually minor but collectively significant projects taking place over a period of time.

Section 15130(a) of the CEQA Guidelines further states that a “cumulative impact consists of an impact which is created as a result of the combination of the project evaluated in the EIR together with other projects causing related impacts.”
In addition, Section 15130(a) of the CEQA Guidelines requires that EIRs discuss the cumulative impacts of a project when the project’s incremental effect is cumulatively considerable. Therefore, the discussion of cumulative impacts in an EIR evaluates if the impacts of the project would be significant when considered in combination with past, present, and future reasonably foreseeable projects, and if the project would make a cumulatively considerable contribution to those impacts.

CEQA recognizes that the analysis of cumulative impacts need not be as detailed as the analysis of project-related impacts but instead should “be guided by the standards of practicality and reasonableness” (CEQA Guidelines, Section 15130[b]). The CEQA Guidelines indicate that, where a lead agency is examining a project with an incremental effect that is not cumulatively considerable, it need not consider the effect significant but shall briefly describe the basis for its conclusion. As further clarified by Section 15065 of the CEQA Guidelines, “cumulatively considerable” means that the incremental effects of an individual project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects of probable future projects. The CEQA Guidelines allow for a project’s contribution to be rendered less than cumulatively considerable with implementation of mitigation.

The geographic scope of the cumulative impact analysis varies depending on the specific environmental issue area being analyzed. The geographic scope defines the geographic area within which projects may contribute to a specific cumulative impact. Therefore, past, present, and reasonably foreseeable future projects within the defined geographic area for a given cumulative issue must be considered.

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CEQA Guidelines, Section 15130(b), presentsthe following two possible approaches for considering past, present, and reasonably foreseeable future projects and indicates that either could be used:

1. A list of past, present, and probable future projects producing related or cumulative impacts, including, if necessary, those projects outside the control of the agency

2. A summary of projections contained in an adopted local, regional, or statewide plan, or related planning document, that describes or evaluates conditions contributing to the cumulative effect
This EIR uses a hybrid approach. The City of Anaheim’s General Plan was adopted in 2004 with a buildout projection of 129,159 residential units, a population of 403,773, approximately 60.52 million square feet of non-residential uses, and 251,397 total jobs.

The City of Anaheim is currently processing its General Plan Focused Update, which includes updates to the Land Use Element, Circulation Element, Zoning Code, Land Use Plan, Zoning Map, and related plans, as well as preparation of a new Environmental Justice Element. The Draft Program Environmental Impact Report for the proposed General Plan Focused Update was made available for public review from December 20, 2024, to February 3, 2025. Upon adoption, the City of Anaheim’s projected buildout would change to 154,801 residential units, a population of 431,340, approximately 113.44 million square feet of non-residential uses, and 274,213 jobs.

The OCVIBE Master Site Plan Project (OCVIBE Project) that borders the project site on the west was approved in 2022, revised in 2024, and is within the Platinum Triangle Mixed Use Overlay Zone, which was included in the City of Anaheim’s adopted General Plan. Existing development is included as part of the existing environmental baseline when evaluating project impacts. The approved OCVIBE Project, is in various stages of development, including the planning phase, design stage, or construction phase. The OCVIBE Project comprises approximately 92.08 net acres, and is generally bounded by State Route 57 to the west, the Santa Ana River to the east, the confluence of the State Route 57 and Santa Ana River to the south, with the Southern California Edison easement area forming the northern boundary. The OCVIBE Project includes the Honda Center (2695 East Katella Avenue), ARTIC (2626 East Katella Avenue), and the ACC office buildings (1400–1600 South Douglass Road). The OCVIBE Project includes the following development intensities with the OCVIBE Master Site Plan Amendment No. 1 that was approved in November 2024:
• Commercial – 1,922,776 GSF
• Office – 251,680 to 576,680 GSF
• Institutional – 250,000 GSF
• Residential – 1,920 to 2,250 Dwelling Units/ up to 2.79 million GSF Chapter 3: Environmental Setting
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The City of Orange General Plan was adopted in 2010, with a buildout projection of 65,680 dwelling units, approximately 70 million square feet of non-residential uses, a population of 194,543, and 120,700 jobs.

Depending on the environmental category, some impacts are site specific, while others may extend beyond city boundaries. Chapter 4, Environmental Analysis, of this Draft EIR provides a discussion of cumulative impacts associated with development and growth in the city and region for each environmental resource area.

Cumulative impact analyses are conducted within the most appropriate geographic boundaries.

Certain cumulative impacts, such as biological resources and geology and soils, considered sitespecific impacts and nearby surrounding areas, while such as those related to air quality and hydrology/water quality, extend across regional boundaries and are assessed in the context of regional plans and defined significance thresholds. Climate change, being a global issue, is analyzed based on state regulations and regional plans designed to address its cumulative effects.

Below is a summary of the approach and scope of cumulative impact analyses, with further details provided in each environmental topical section:
• Air Quality. Air quality impacts include regional (cumulative) impacts and localized impacts. For cumulative impacts, the analysis is based on the regional boundaries of the Southern California Air Basin.
• Biological Resources. The biological resources survey area for the project included the project site and the 100-foot buffer around the project site. The cumulative analysis considers surrounding areas with similar biological resources within the Cities of Anaheim and Orange.
• Cultural Resources. Cultural resources impacts are generally site specific. Cumulative impacts consider the potential effects of the project, combined with impacts from other sitespecific developments in Anaheim and Orange allowed in their respective general plans. • Geology and Soils. Geology and soils impacts are site specific, and the cumulative impacts area considered for geology and soils impact is limited to the project site boundaries. • Greenhouse Gas Emissions. GHG emissions impacts are not site-specific impacts but cumulative impacts. Therefore, the analysis in Section 4.5 provides the analysis to determine if the project would make a cumulatively considerable contribution to a significant cumulative GHG emissions impact.
• Hazards and Hazardous Materials. The cumulative analysis considers surrounding areas within the Cities of Anaheim and Orange, as projected in their general plans. • Hydrology and Water Quality. The recharged groundwater and stormwater runoff from the project site could impact downstream water quality and off-site drainage facilities.

Cumulative impacts are analyzed within the Santa Ana River Watershed.

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• Noise. Cumulative construction impacts are based on nearby projects that may have concurrent construction schedules. Cumulative operational impacts are typically based on existing development combined with the project and reasonably foreseeable nearby future development.
• Transportation. The cumulative vehicle miles traveled traffic impact analysis consider the potential for the project in conjunction with other development projects as projected and allowed in the Cities of Anaheim and Orange per their general plans. • Tribal Cultural Resources. Cumulative impacts related to Tribal Cultural Resources are based on the local Native American Tribes’ culturally significant areas and include, but are not limited to, cultural landscapes and regions, specific heritage sites, and other Tribal Cultural Places.

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Chapter 4: Environmental Analysis
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Chapter 4 Environmental Analysis
Sections 4.1 through 4.10 in this chapter contain a discussion of the potential environmental effects from implementation of the OC River Walk Project (project), including the current environmental setting, regulatory setting, method of analysis, thresholds of significance, impacts (including cumulative), and mitigation measures.

Scope of the Environmental Impacts Analysis
In accordance with Appendix G of the California Environmental Quality Act (CEQA) Guidelines, the potential environmental effects from the project are analyzed in this chapter for the following environmental issue areas. Other environmental issues identified in Appendix G of the CEQA Guidelines have been scoped out from further analysis, as they were determined to have no impact or a less than significant impact in the Initial Study prepared during the Notice of Preparation process. The Notice of Preparation and the accompanying Initial Study were circulated for public review from March 23, 2023, through April 24, 2023, and are included as Appendix A to this Draft Environmental Impact Report (EIR). Environmental issues found to have no or less than significant impacts are also included in Section 6.4, Effects Found Not to Be Significant. • Air Quality
• Biological Resources
• Cultural Resources
• Geology and Soils
• Greenhouse Gas Emissions
• Hazards and Hazardous Materials
• Hydrology and Water Quality
• Noise
• Transportation
• Tribal Cultural Resources
Format of the Environmental Impact Analysis
The following subsections compose each of the 10 environmental issue area sections in Sections

4.1 through 4.10 of this Draft EIR.

Environmental Setting
This subsection describes the current environmental setting of each environmental issue area.

According to Section 15125 of the CEQA Guidelines, an EIR must include a description of the existing physical environmental conditions in the project vicinity to provide the “baseline conditions” against which project-related impacts are compared. Normally, the baseline conditions are the physical conditions that exist when the Notice of Preparation (NOP) is published. The NOP for the project was published on March 23, 2023, and the baseline conditions contained in this Draft EIR are generally taken from this time period. However, the CEQA Guidelines and applicable case law recognize that the date for establishing an environmental baseline cannot always be rigid. Physical environmental conditions may vary over a range of time periods; thus, the use of environmental baselines that differ from the publication date of the NOP is reasonable Chapter 4: Environmental Analysis
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and appropriate when conducting the environmental analyses. Some sections rely on a variety of data to establish an applicable baseline. For example, in Sections 4.1, Air Quality; 4.2, Biological Resources; 4.3, Cultural Resources; 4.6, Hazards and Hazardous Materials, 4.9, Transportation; and 4.10, Tribal Cultural Resources, available data was months and sometimes several years old.

Therefore, projections regarding how those conditions might have changed were incorporated into the EIR sections and corresponding technical reports.

This subsection also provides a summary of regulations, plans, policies, and laws that are relevant to each environmental issue area at the federal, state, and local levels.

Thresholds of Significance
This subsection identifies the criteria used to determine whether potential environmental effects are significant. The thresholds of significance used in this analysis were primarily based on Appendix G of the CEQA Guidelines. However, in some cases, thresholds were developed specifically for this analysis or were adapted from standards adopted by other agencies or entities. This subsection defines the type, amount, and/or extent of impact that would be considered a significant, adverse change in the environment. Some thresholds of significance are quantitative, while others are qualitative. The thresholds of significance are intended to assist the reader in understanding how and why this Draft EIR reaches a conclusion that an impact is significant, potentially significant, or less than significant.

Plans, Programs, and Policies
This subsection addresses plans, programs, and policies relevant to the project.

Environmental Impacts
This subsection describes the potential environmental impacts of the project and, based on the thresholds of significance, concludes if the environmental impacts would be significant, potentially significant, or less than significant or if no impact would occur. Each impact criterion is addressed in its own subsection. This format is designed to assist the reader in quickly identifying the subject of each impact analysis and for use in Table ES-2, Summary of Environmental Impacts and Mitigation Measures, which forms the basis of the Mitigation Monitoring and Reporting Program.

The analysis of environmental impacts considers both the construction and operational phases associated with implementation of the project. As required by Section 15126.2(a) of the CEQA Guidelines, direct, indirect, long-term, short-term, on-site, and/or off-site impacts are addressed, as appropriate, for the environmental issue area being analyzed. This Draft EIR uses the following terms to describe the level of significance of impacts identified during the course of the environmental analysis:
• No Impact: “No impact” refers to implementation of the proposed project having no impact on environmental conditions.
• Less than Significant Impact: “Less than significant” refers to two conditions:

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− Impacts resulting from implementation of the project that are not likely to exceed the defined standards of significance.
− Potentially significant impacts before implementation of mitigation measures.

If implementation of the specified mitigation measures would reduce the potentially significant impact to a level that does not exceed the defined standards of significance, the impact is considered less than significant. • Potentially Significant Impact: “Potentially significant” refers to impacts resulting from implementation of the project that may exceed defined standards of significance before mitigation is considered.
• Significant and Unavoidable Impact: “Significant and unavoidable” refers to impacts resulting from implementation of the project that cannot be eliminated or reduced to below the defined standards of significance or a less than significant level through implementation of feasible mitigation measures.

A “significant effect” is defined by Section 15382 of the CEQA Guidelines as “a substantial, or potentially substantial, adverse change in any of the physical conditions within the area affected by the project including land, air, water, minerals, flora, fauna, ambient noise, and objects of historic or aesthetic significance. An economic or social change by itself shall not be considered a significant effect on the environment . . . [but] may be considered in determining whether the physical change is significant.”
Cumulative Impacts
CEQA requires that EIRs discuss cumulative impacts in addition to project impacts. In accordance with CEQA, the discussion of cumulative impacts must reflect the severity of the impacts and the likelihood of their occurrence; however, the discussion need not be as detailed as the discussion of environmental impacts attributable to the project alone. Further, the discussion should be guided by the standards of practicality and reasonableness (CEQA Guidelines, Section 15130[b]). Please refer to Section 3.3 of this Draft EIR for additional information on cumulative impact methodology.

Level of Significance before Mitigation
This subsection identifies the level of significance of project impacts before mitigation measures are implemented.

Mitigation Measures
This subsection identifies mitigation measures for each impact criterion when applicable.

Level of Significance after Mitigation
This subsection identifies the level of significance of project impacts after mitigation measures are implemented.

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Section 4.1: Air Quality
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4.1 Air Quality
This section evaluates the potential for impacts on air quality resulting from implementation of the OC River Walk Project (project). Information presented in this section related to construction and operation emissions is based on California Emissions Estimator Model (CalEEMod) modeling prepared by Harris & Associates and included in Appendix C, Air Quality/GHG Data, to this Environmental Impact Report (EIR).

4.1.1 Environmental Setting

4.1.1.1 Regulatory Setting
This section describes the federal, state, and local regulatory framework adopted to address air quality.

Federal
Federal Clean Air Act (U.S. Code, Title 42, Section 7401 et seq.) The Clean Air Act (CAA) of 1970 is the comprehensive federal law that regulates air emissions from stationary and mobile sources. The CAA authorizes the U.S. Environmental Protection Agency (USEPA) to establish National Ambient Air Quality Standards (NAAQS) to protect public health and public welfare and to regulate emissions of hazardous air pollutants. Current NAAQS are listed in Table 4.1-1, National and California Ambient Air Quality Standards. The primary standards listed in Table 4.1-1 have been set at levels intended to protect public health. The USEPA has classified air basins (or portions thereof) as being in “attainment,” “nonattainment,” or “unclassified” for each criteria air pollutant based on if the NAAQS have been achieved. Nonattainment areas are air basins that do not meet one or more of the NAAQS and are subject to additional restrictions as required by the USEPA. If an area is designated unclassified, it is because inadequate air quality data was available as a basis for a non-attainment or attainment designation.

The USEPA classifies the South Coast Air Quality Management District (SCAQMD) as in attainment for the federal carbon monoxide (CO), nitrogen dioxide (NO2), lead, respirable particulate matter (PM10), and sulfur dioxide (SO2) standards. It is unclassifiable for PM10 with respect to federal air quality standards. The SCAQMD is classified as in non-attainment for the federal ozone (O3) standard and fine particulate matter (PM2.5) (SCAQMD 2022). Table 4.1-2, South Coast Air Quality Management District Attainment Status, lists the attainment status of the SCAQMD for criteria air pollutants.

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Table 4.1-1. National and California Ambient Air Quality Standards Pollutant Averaging Time
California Standards1 Federal Standards2
Concentration3 Primary3, 4 Secondary3, 5
Ozone (O3)6
1-Hour 0.09 ppm (180 μg/m3) — Same as Primary
8 Standards -Hour 0.070 ppm (137 μg/m3) 0.070 ppm (137 μg/m3) Respirable
Particulate Matter
(PM10)7
24-Hour 50 μg/m3 150 μg/m3
Same as Primary
Standards Annual Arithmetic
Mean 20 μg/m3 —
Fine Particulate
Matter (PM2.5)7
24-Hour — 35 μg/m3 Same as Primary
Standards
Annual Arithmetic
Mean 12 μg/m3 9 μg/m3 15 μg/m3
Carbon Monoxide
(CO)
8-Hour 9 ppm (10 mg/m3) 9 ppm (10 mg/m3) None
1-Hour 20 ppm (23 mg/m3) 35 ppm (40 mg/m3)
Nitrogen Dioxide
(NO2) 8
Annual Arithmetic
Mean 0.030 ppm (57 μg/m3) 0.053 ppm (100 μg/m3) Same as Primary Standard
1-Hour 0.18 ppm (470 mg/m3) 100 ppb (188 μg/m3)
Sulfur Dioxide
(SO2)9
Annual Arithmetic
Mean — 0.030 ppm (for certain areas)
—
24-Hour 0.04 ppm (105 μg/m3) 0.14 ppm (for certain areas) — 3-Hour — — 0.5 ppm (1,300
μg/m3)
1-Hour 0.25 ppm (655 μg/m3) 75 ppb (196 μg/m3) —
Lead10, 11
30-Day Average 1.5 μg/m3 — —
Calendar Quarter — 1.5 μg/m3 (for certain areas) Same as Primary Standard Rolling 3-Month
Average7 — 0.15 μg/m3
Visibility-Reducing
Particles12 8-Hour Refer to Footnote 12 No Federal Standards Sulfates 24-Hour 25 μg/m3 No Federal Standards
Hydrogen Sulfide 1-Hour 0.03 ppm (42 μg/m3) No Federal Standards Vinyl Chloride10 24-Hour 0.01 ppm (26 μg/m3) No Federal Standards Source: CARB 2024a, 2024b.

Notes: μg/m3 = micrograms per cubic meter; mg/m3 = milligram per cubic meter; ppb = parts per billion; ppm = parts per million 1 California standards for O3, CO, SO2 (1-hour and 24-hour), NO2, PM10, PM2.5, and visibility-reducing particles are values that are not to be exceeded. The standards for sulfates, lead, hydrogen sulfide, and vinyl chloride standards are not to be equaled or exceeded. The California ambient air quality standards are listed in the Table of Standards in California Code of Regulations, Title 17, Section 70200.
2 National standards (other than O3, PM, and those based on annual averages) are not to be exceeded more than once per year.

The O3 standard is attained when the fourth highest 8-hour concentration measured at each site in 1 year, averaged over 3 years, is equal to or less than the standard. For PM10, the 24-hour standard is attained when the expected number of days per calendar year with a 24-hour average concentration above 150 µg/m3 is equal to or less than 1. For PM2.5, the 24-hour standard is attained when 98 percent of the daily concentrations, averaged over 3 years, are equal to or less than the standard. Contact the USEPA for further clarification and current national policies.
3 Concentration expressed first in units in which it was promulgated. Equivalent units given in parenthesis are based on a reference temperature of 25 degrees Celsius (°C) and a reference pressure of 760 torr. Most measurements of air quality are to be corrected to a reference temperature of 25°C and a reference pressure of 760 torr; ppm in this table refers to ppm by volume, or micromoles of pollutant per mole of gas.

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4 National Primary Standards: The levels of air quality necessary, with an adequate margin of safety to protect the public health. 5 National Secondary Standards: The levels of air quality necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.
6 On October 1, 2015, the national 8-hour O3 primary and secondary standards were lowered from 0.075 to 0.070 ppm. 7 On February 7, 2024, the national annual PM2.5 primary standard was lowered from 12.0 μg/m3 to 9.0 μg/m3. The existing national 24-hour PM2.5 standards (primary and secondary) were retained at 35 μg/m3 , as was the annual secondary standard of 15.0 μg/m3.

The existing 24-hour PM10 standards (primary and secondary) of 150 μg/m3 also were retained. The form of the annual primary and secondary standards is the annual mean, averaged over 3 years. 8 To attain the 1-hour national standard, the 3-year average of the annual 98th percentile of the 1-hour daily maximum concentrations at each site must not exceed 100 ppb. Note that the national 1-hour standard is in units of ppb. California standards are in units of ppm. To directly compare the national 1-hour standard to the California standards, the units can be converted from ppb to ppm. In this case, the national standard of 100 ppb is identical to 0.100 ppm. 9 On June 2, 2010, a new 1-hour SO2 standard was established, and the existing 24-hour and annual primary standards were revoked. To attain the 1-hour national standard, the 3-year average of the annual 99th percentile of the 1-hour daily maximum concentrations at each site must not exceed 75 ppb. The 1971 SO2 national standards (24-hour and annual) remain in effect until 1 year after an area is designated for the 2010 standard, except that in areas designated non-attainment for the 1971 standards, the 1971 standards remain in effect until implementation plans to attain or maintain the 2010 standards are approved.

Note that the 1-hour national standard is in units of ppb. California standards are in units of ppm. To directly compare the 1-hour national standard to the California standard, the units can be converted to ppm. In this case, the national standard of 75 ppb is identical to 0.075 ppm.
10 The California Air Resources Board (CARB) had identified lead and vinyl chloride as toxic air contaminants (TACs) with no threshold level of exposure for adverse health effects determined. These actions allow for the implementation of control measures at levels below the ambient concentrations specified for these pollutants. 11 The national standard for lead was revised on October 15, 2008, to a rolling 3-month average. The 1978 lead standard (1.5 μg/m3 as a quarterly average) remains in effect until 1 year after an area is designated for the 2008 standard, except that in areas designated non-attainment for the 1978 standard, the 1978 standard remains in effect until implementation plans to attain or maintain the 2008 standard are approved.
12 In 1989, CARB converted both the general statewide 10-mile visibility standard and the Lake Tahoe 30-mile visibility standard to instrumental equivalents, which are “extinction of 0.23 per kilometer” and “extinction of 0.07 per kilometer” for the statewide and Lake Tahoe Air Basin standards, respectively.

Table 4.1-2. South Coast Air Quality Management District Attainment Status Pollutant California Standards Federal Standards
Ozone (O3) (1-Hour) Non-attainment Non-attainment
Ozone (O3) (8-Hour) Non-attainment Non-attainment
Respirable Particulate Matter (PM10) Non-attainment Attainment Fine Particulate Matter (PM2.5) Non-attainment Non-attainment Carbon Monoxide (CO) Attainment Attainment/Unclassifiable1 Nitrogen Dioxide (NO2) Attainment Attainment/Unclassifiable Lead Attainment Attainment/Unclassifiable
Sulfur Dioxide (SO2) Attainment Attainment
Source: SCAQMD 2016.

Notes:
1 Unclassified; indicates data is not sufficient for determining attainment or non-attainment.

The CAA requires states to develop a plan to attain and maintain the NAAQS in all areas of the country and a specific plan to attain the standards for each area designated non-attainment for a NAAQS. These plans, known as State Implementation Plans, are developed by state and local air quality management agencies and submitted to the USEPA for approval. The State Implementation Plan includes strategies and control measures to attain the NAAQS by deadlines established by the CAA. The State Implementation Plan is periodically modified to reflect the latest emissions inventories, plans, and rules and regulations of air basins as reported by the agencies with jurisdiction over them.

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State
Air Quality and Land Use Handbook: A Community Health Perspective The California Air Resources Board (CARB) developed the Air Quality and Land Use Handbook:

A Community Health Perspective to provide guidance on land use compatibility with sources of toxic air contaminants (TACs) (CARB 2005). These sources include freeways and high-traffic roads, commercial distribution centers, rail yards, refineries, dry cleaners, gasoline stations, and industrial facilities. The handbook is not a law or adopted policy but offers advisory recommendations for the siting of sensitive receptors near uses associated with TACs. The handbook indicates that land use agencies must balance other considerations, including housing and transportation needs, economic development priorities, and other quality-of-life issues.

California Ambient Air Quality Standards
CARB, a part of the California Environmental Protection Agency, is responsible for the coordination and administration of air pollution control programs in California. The CAA allows states to adopt ambient air quality standards and other regulations if they are at least as stringent as federal standards.

California has adopted ambient air quality standards (CAAQS), listed in the Table of Standards in California Code of Regulations, Title 17, Section 70200, and provided in Table 4.1-1. Similar to the NAAQS, areas have been designated as attainment, non-attainment, or unclassified with respect to the CAAQS. As shown in Table 4.1-2, the SCAQMD is in non-attainment with the CAAQS for O3, PM10, and PM2.5. The SCAQMD is designated as an attainment area for the state CO, NO2, SO2, and lead.

Toxic Air Contaminant Regulations
California regulates TACs primarily through the Tanner Air Toxics Act (Assembly Bill [AB] 1807) and the Air Toxics Hot Spots Information and Assessment Act of 1987 (AB 2588, Hot Spots Act). The act sets forth a formal procedure for CARB to designate substances as TACs. This includes research, public participation, and scientific peer review before CARB designates a substance as a TAC. To date, CARB has designated nearly 200 compounds as TACs. The majority of estimated health risks from TACs can be attributed to a relatively small number of compounds, the most important being diesel particulate matter from diesel-fueled engines.

Regional
South Coast Air Quality Management District
The SCAQMD develops rules and regulations, establishes permitting requirements for stationary sources, inspects emission sources, and enforces such measures through educational programs or fines, when necessary. The SCAQMD is directly responsible for reducing emissions from stationary, mobile, and indirect sources. It has responded to this requirement by preparing a sequence of Air Quality Management Plans (AQMPs). Most recently, in December 2022, the SCAQMD Governing Board adopted the 2022 AQMP. The 2022 AQMP is focused on attaining Section 4.1: Air Quality
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the 2015 8-hour ozone standard (70 parts per billion) for the South Coast Air Basin (SCAB) and Coachella Valley. The 2022 AQMP builds upon measures already in place from previous AQMPs.

It also includes a variety of additional strategies such as regulation, accelerated deployment of available cleaner technologies (e.g., zero emission technologies, when cost-effective and feasible, and low NOx technologies in other applications), best management practices, co-benefits from existing programs (e.g., climate and energy efficiency), incentives, and other CAA measures to achieve the 2015 8-hour ozone standard. The 2022 AQMP was approved and adopted by CARB on January 26, 2023. The 2022 AQMP strategy includes the following:
• Wide adoption of zero emissions technologies anywhere available • Low NOx technologies where zero emissions aren’t feasible • Federal Action
• Zero emissions technologies for residential and industrial sources such as water and space heaters in buildings and homes regionwide
• Incentive funding in environmental justice areas
• Prioritize benefits on the most disadvantaged communities Additionally, the project must comply with applicable SCAQMD rules and regulations. The following are the rules that the project may be required to comply with, primarily during construction:
• Rule 402: Prohibits a person from discharging from any source whatsoever such quantities of air contaminants or other material which cause injury, detriment, nuisance, or annoyance to any considerable number of persons or to the public, or which endanger the comfort, repose, health or safety of any such persons or the public, or which cause, or have a natural tendency to cause, injury or damage to business or property. • Rule 403: Governs emissions of fugitive dust during construction and operation activities. Compliance with this rule is achieved through the application of standard Best Management Practices.
• Rule 1108: Governs the sale, use, and manufacturing of asphalt and limits the volatile organic compound (VOC) content in asphalt used in the South Coast Air Basin. This rule would regulate the VOC content of asphalt used during construction. Therefore, all asphalt used during construction of the Proposed Project must comply with SCAQMD Rule 1108.

Southern California Association of Governments
The Southern California Association of Governments is the regional planning agency for Los Angeles, Orange, Ventura, Riverside, San Bernardino and Imperial Counties and addresses regional issues relating to transportation, the economy, community development and the environment. The Southern California Association of Governments is the federally designated metropolitan planning organization for the majority of the Southern California region and is the Section 4.1: Air Quality
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largest metropolitan planning organization in the nation. With respect to air quality planning, the Southern California Association of Governments has prepared the Regional Transportation Plan and Regional Transportation Improvement Plan, which addresses regional development and growth forecasts. These plans form the basis for the land use and transportation components of the AQMP, which are used in the preparation of air quality forecasts and in the consistency, analysis included in the AQMP. The Regional Transportation Plan, Regional Transportation Improvement Plan, and AQMP are based on projections originating within the City and County General Plans.

In April 2024, the Southern California Association of Governments approved the Final 2025–2050 RTP/SCS, Connect SoCal 2024. Connect SoCal 2024 outlines a vision for a more resilient and equitable future, with investment, policies and strategies for achieving the region’s shared goals through 2050. Goals of the plan include more efficient development patterns, reduced congestion, expanded multimodal travel options, and reduced greenhouse gas emissions from passenger vehicles. Priority Development Areas are a key focus of the plan to increase development in locations where people can access alternative modes of transportation or make short trips for day-to-day tasks.

Local
City of Anaheim General Plan Green Element
The City of Anaheim General Plan’s Green Element, adopted in 2004, contains goals that focus on the reduction of vehicle trips and vehicle emissions (City of Anaheim 2004). The Green Element comprehensively addresses topics concerning conservation, open space, parks and recreation, trails, and public landscaping. Goals and policies from the Green Element relating to air quality that are applicable to the project are listed below:
• Goal 8.1: Reduce locally generated emissions through improved traffic flows and construction management practices.
− Policy 1. Reduce vehicle emissions through traffic flow improvements, such as traffic signal synchronization, Intelligent Transportation Systems, the Scoot Adaptive Traffic Control System, and related capital improvements. − Policy 2. Regulate construction practices, including grading, dust suppression, chemical management, and encourage pre-determined construction routes that minimize dust and particulate matter pollution.
• Goal 9.1: Reduce single-occupancy vehicle trips.
− Policy 3. Encourage use of vanpools and carpools by providing priority parking through the project design process.
− Policy 4. Encourage bicycle and pedestrian travel by improving the City’s trail and bikeway master plan and by providing convenient links between the trail system and desired destinations.

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• Goal 13.1: Expand citizen and business outreach programs relating to policies that improve air quality.
− Policy2. Disseminate air quality educational materials to residents, businesses and schools.

City of Orange General Plan Natural Resources Element
The City of Orange General Plan Natural Resources Element, adopted in 2010, contains goals that focus on the reduction of vehicle trips and vehicle emissions (City of Orange 2010). The Natural Resources Element comprehensively addresses topics concerning conservation, open space, parks and recreation, trails, and public landscaping, as well as preservation and management of renewable and non-renewable natural resources. The applicable Natural Resources Element goal related to air quality is listed below:
• Goal 2.0: Protect air, water, and energy resources from pollution and overuse. − Policy 2.1. Cooperate with the South Coast Air Quality Management District (SCAQMD) and other regional agencies to implement and enforce regional air quality management plans.
− Policy 2.2. Support alternative transportation modes, alternative technologies, and bicycle- and pedestrian-friendly neighborhoods to reduce emissions related to vehicular travel.
− Policy 2.10. Work toward replacing existing City vehicles with ultra low or zero emission vehicles. At a minimum, new City vehicles shall be low emission vehicles as defined by the California Air Resources Board, except if certain vehicle types are not available in the marketplace. Public safety vehicles are exempted from this requirement.

4.1.1.2 Existing Conditions
Climate
The project site is located within the SCAB, which includes all of Orange County and the urbanized portions of Los Angeles, Riverside, and San Bernardino Counties. The SCAB is arid, with virtually no rainfall and abundant sunshine during the summer months. The SCAB has light winds and poor vertical mixing compared to the other large urban areas in the United States. The combination of poor dispersion and abundant sunshine drives the photochemical reactions that form pollutants (such as ozone [O3]) and provide conditions especially favorable to the formation of smog. The SCAB is bound to the north and east by mountains with maximum elevations exceeding 10,000 feet. The unfavorable combination of meteorology, topography, and emissions from the nation’s second largest urban area results in the SCAB having some of the worst air quality in the United States (SCAQMD 2022).

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Temperature and precipitation levels in the Cities of Anaheim and Orange vary throughout the year. In general, August is typically the warmest month, and December is typically the coolest month. Almost all the annual rainfall comes from the fringes of mid-latitude storms from late November to early April, with summers being almost completely dry (WRCC 2025).

Air Pollutants and Effects
Air quality laws and regulations have historically divided air pollutants into two broad categories:
criteria air pollutants and non-criteria air pollutants, or TACs. Criteria air pollutants are a group of common air pollutants regulated by federal and state governments through ambient air quality standards based on criteria regarding the health and environmental effects of pollution. The criteria air pollutants pertinent to the analysis in this memorandum are carbon monoxide (CO), nitrogen oxides (NOx), ozone (O3), particulate matter (particulate matter measuring no more than 10 microns in diameter [PM10] and particulate matter measuring no more than 2.5 microns in diameter [PM2.5]), and sulfur dioxide (SO2). The following describes the health effects of these criteria air pollutants.

Carbon Monoxide
CO is a colorless, odorless, poisonous gas produced by combustion processes, primarily mobile sources. When CO gets into the body, it combines with chemicals in the blood and prevents blood from providing oxygen to cells, tissues, and organs. Because the body requires oxygen for energy, high-level exposure to CO can cause serious health effects, including death (USEPA 2024a).

Nitrogen Oxides
NOx is a general term pertaining to compounds including nitric oxide (NO), nitrogen dioxide (NO2), and other nitrogen oxides. NOx is produced from burning fuels, including gasoline, diesel, and coal.

NOx reacts with volatile organic compounds (VOCs) to form ground-level O3 (smog). NOx is linked to a number of adverse respiratory system effects (USEPA 2024b).

Ozone
Ground-level O3 is not emitted directly into the air but is formed by chemical reactions of “precursor” pollutants (NOx and VOCs) in the presence of sunlight. Major emissions sources include NOx and VOC emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents. O3 can trigger a variety of health problems, particularly for sensitive receptors, including children, older adults, and people of all ages who have lung diseases, such as asthma (USEPA 2024c).

Particulate Matter
Particulate matter includes dust, metals, organic compounds, and other tiny particles of solid materials that are released into and move around in the air. Particulates are produced by many sources, including the burning of diesel fuel by trucks and buses, industrial processes, and fires.

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Particulate matter is measured in microns, which are 1 millionth of 1 meter in length (or 1 thousandth of 1 millimeter). PM10 is small particulate matter measuring no more than 10 microns in diameter, while PM2.5 is fine particulate matter measuring no more than 2.5 microns in diameter.

Both PM2.5 and PM10 can be inhaled and deposited throughout the airways. Locations of particle deposition in the lung depend on particle size. PM2.5 is more likely to travel into and deposit on the surface of the deeper parts of the lung, while PM10 is more likely to deposit on the surfaces of the larger airways of the upper region of the lung. Inhalation of particulate matter can cause nose and throat irritation and heart and lung problems (USEPA 2024d).

Sulfur Dioxide
SO2 is formed primarily by the combustion of sulfur-containing fossil fuels, especially at power plants and industrial facilities. SO2 is linked to a number of adverse effects on the respiratory system (USEPA 2024e).

Existing Ambient Air Quality
The air quality at any site is dependent on the regional air quality and local pollutant sources. Regional air quality is determined by the release of pollutants throughout the SCAB. Estimates of the existing emissions in the SCAB provided in the 2022 AQMP indicate that collectively, mobile sources account for 46 percent of the VOC, 85 percent of the NOx emissions, 89 percent of the CO emissions and 29 percent of directly emitted PM2.5, with another 18 percent of PM2.5 from road dust (SCAQMD 2022).

The SCAQMD has divided the SCAB into 38 air monitoring areas with a designated ambient air monitoring station representative of each area. The project site is located in the Central Orange County Air Monitoring Area (Area 17). The nearest air monitoring station to the project site is the Anaheim Route 5 Near Road Station located at 812 West Vermont Street in Anaheim, California (Anaheim–West Vermont Street Monitoring Station) and approximately 2.6 miles west of the project site. As not all monitoring stations monitor all pollutants, data was also taken from the Anaheim–Loara School Monitoring Station located approximately 3.8 miles west of the project site at 1630 Pampas Lane, Anaheim (Anaheim–Pampas Lane Monitoring Station) for those pollutants which are not measured at the Anaheim–West Vermont Street Monitoring Station. Table 4.1-3, Air Quality Monitoring Summary, summarizes the monitored pollutant levels from the Anaheim–Pampas Lane Monitoring Station and the Anaheim–West Vermont Street Monitoring Station from 2021 through 2023, which is the most recent 3-year period available. The data shows that during the past few years, monitored conditions have exceeded the ozone, PM2.5 PM10 standards.

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Source: CARB 2024b.

Notes: CAAQS = California Ambient Air Quality Standard; NAAQS = National Ambient Air Quality Standard; ppm = parts per million * insufficient data available to determine value

4.1.2 Thresholds of Significance
According to Appendix G of the California Environmental Quality Act (CEQA) Guidelines, the project would have a significant impact on air quality if it would:
• Threshold AQ-1: Conflict with or obstruct implementation of the applicable air quality plan. • Threshold AQ-2: Result in a cumulatively considerable net increase of any criteria air pollutant for which the project region is non-attainment under an applicable federal or state ambient air quality standard.
• Threshold AQ-3: Expose sensitive receptors to substantial pollutant concentrations. • Threshold AQ-4: Result in other emissions (such as those leading to odors) adversely affecting a substantial number of people.

Table 4.1-3. Air Quality Monitoring Summary
Pollutant Standard Monitoring Station 2021 2022 2023
O3
Maximum 1-hour concentration (ppm)
Anaheim-Pampas Lane

0.089 0.102 0.089
Number of days exceeded State: > 0.12 ppm 0 1 0
Maximum 8-hour concentration (ppm) 0.068 0.076 0.076
Number of days exceeded
Federal: > 0.07 ppm 0 1 2
State: > 0.07 ppm 0 1 2
PM2.5
Maximum 24-hour concentration (µg/m3)
Anaheim-Pampas Lane

54.4 33.1 45.6
Number of days exceeded Federal: > 35 µg/m3 10 0 1
Annual arithmetic average concentration (µg/m3) 11.6 9.9 * Exceeded for the year State: > 12 µg/m3 No No No
PM10
Maximum 24-Hour Concentration
Anaheim-Pampas Lane

63.6 67.0 97.8
Number of days exceeded
Federal: >150 µg/m3) 0 0 0
State: > 50 µg/m3 1 1 1
Annual arithmetic average concentration (µg/m3) 23.2 * * NO2
Maximum 1-hour concentration (ppm) Anaheim- W Vermont Street0.072 0.062 0.058 Number of days exceeded State: > 0.18 ppm 0 0 0
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The Initial Study (Appendix A to this EIR) determined that the following thresholds would have less than significant or no impact, and these environmental topics will not be addressed further in this section of the Draft EIR:
• Threshold AQ-1
• Threshold AQ-2 (operation impact only)
• Threshold AQ-3 (operation impact only)
• Threshold AQ-4 (operation impact only)

4.1.3 Plans, Programs, and Policies
This section addresses plans, programs, and policies relevant to the project.

PPP AQ-1 The project is required to comply with applicable rules and regulations set forth by SCAQMD, including but not limited to Rules 402, 403, and 1108.

PPP AQ-2 The project is required to comply with the goals and policies related to air quality outlined in the City of Anaheim Green Element and the City of Orange Natural Resources Element.

4.1.4 Environmental Impacts
The following sections address various potential impacts relating to air quality that could result from implementation of the project.

4.1.4.1 Threshold AQ-2: Cumulative Increase in Criteria Air Pollutant Emissions (Construction)
Impact Analysis
Construction activities would result in the temporary generation of air pollutants from operation of heavy construction equipment and generation of fugitive dust in the construction area and emissions from worker vehicle trips and hauling of import and export materials. Construction emissions were modeled for the project using CalEEMod Version 2022.1.1.29 using the linear construction project model. The CalEEMod includes default assumptions for construction and operation of a variety of land use development or vertical development types (e.g., residential or commercial development), and construction of linear infrastructure (e.g., pedestrian, bike, and vehicular bridge, trails, and roadway construction). As a new linear active transportation facility with paved trails and pedestrian/bike bridges, the linear model is most appropriate for the project.

Construction is anticipated to take up to 36 months but is conservatively assumed to take approximately 24 months for this analysis. Based on information provided by the project engineering team (PACE), construction assumes that 11,600 cubic yards of soil would be exported during site preparation and approximately 90,000 cubic yards of soil would be stockpiled for use Section 4.1: Air Quality
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on site. Excavation assumes the export and import of 17,700 cubic yards of soil. Pavement is assumed to require 11,460 cubic yards of imported paving material. CalEEMod default construction equipment fleet and vehicle trips for workers and haul trips are assumed.

Implementation of dust control practices is assumed consistent with SCAQMD Rule 403, including watering and limiting vehicle speeds.

The project’s estimated maximum daily construction emissions and the SCAQMD’s regional emissions thresholds are summarized in Table 4.1-4, Construction-Related Regional Pollutant Emissions (pounds/day). These significance thresholds are updated as needed to appropriately represent the most current technical information and attainment status in the SCAB. Any projects in the SCAB with daily emissions that exceed any of the indicated thresholds should be considered as having an individually and cumulatively significant air quality impact (SCAQMD 2023).

Construction phases are anticipated to occur sequentially. As shown in Table 4.1-4, the project daily construction emissions would not exceed the SCAQMD thresholds for any pollutant during any phase. It should be noted that even if construction phases were to occur concurrently, the total daily maximum would not exceed the SCAQMD maximum daily thresholds except for NOx emissions. As such, the project would not result in a cumulatively considerable net increase of any criteria air pollutant during construction. This impact would be less than significant.

Table 4.1-4. Construction-Related Regional Pollutant Emissions (pounds/day)1 Activity VOC NOx CO SO2 PM10 PM2.5
Site Preparation and Clearing 1 10 11 <1 4 1
Grading and Excavation2 9 78 93 <1 11 4
Drainage, Utilities, and Subgrade 7 55 65 <1 9 3
Paving and Construction 1 13 22 <1 3 1
Maximum Daily Emissions 9 78 93 <1 11 4
SCAQMD Thresholds 75 100 550 150 150 55
Significant? No No No No No No
Source: CAPCOA 2022. Appendix C of the Draft EIR.

Notes: CO = carbon monoxide; NOx = oxides of nitrogen; PM10 = particulate matter less than 10 microns in diameter; PM2.5 = particulate matter less than 2.5 microns in diameter; SOx = sulfur oxides; VOC = volatile organic compounds. 1 Includes on-site and off-site emissions. 2 On-site grading PM10 and PM2.5 emissions assume compliance with SCAQMD Rule 403 for fugitive dust control measures.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

Section 4.1: Air Quality
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4.1.4.2 Threshold AQ-3: Sensitive Receptors (Construction) Impact Analysis
The SCAQMD considers a sensitive receptor to be a location where a sensitive individual could remain for 24 hours, such as residences, hospitals, or convalescent facilities (SCAQMD 2008).

Those who are sensitive to air pollution include children, older adults, and people with pre-existing respiratory or cardiovascular illness. The nearest sensitive receptors to the project site include Extended Stay America hotel, approximately 75 feet east of nearest edge of the project site, and Garrison Apartments, located approximately 500 feet east of the project site.

Localized Impacts from Criteria Air Pollutants
The SCAQMD’s screening look-up tables, or Localized Significance Thresholds (LSTs) are used in determining the significance of the project’s localized air quality impacts, and to determine if further detailed analysis is required. LSTs represent the maximum emissions from a project that would not cause or contribute to an exceedance of the most stringent applicable NAAQS and CAAQS at the nearest sensitive receptor. Receptor locations are off-site locations where individuals may be exposed to emissions from project activities.

The LST analysis for construction is dependent, in part, on the number of acres that would be disturbed during each phase of construction. The disturbed area per day is representative of a piece of equipment making multiple passes over the same land area. Construction activities associated with the project would have the potential to generate air emissions and toxic air contaminant emissions. A complete list of off-road equipment assumed for construction activities, hours of operation, and maximum estimated emissions are presented in Appendix C of this Draft EIR.

The local air emissions from construction were analyzed using the SCAQMD’s Mass Rate Localized Significant Threshold Look-up Tables and the methodology described in the LST Methodology prepared by SCAQMD (SCAQMD 2008, 2009). Consistent with SCAQMD guidance, the LST analysis includes only on-site emissions during construction (SCAQMD 2008).

Table 4.1-5, Local Construction Emissions at the Nearest Receptor, shows the on-site daily emissions from the CalEEMod for the different construction phases compared to the SCAQMD’s LST emissions thresholds. The LST emissions threshold options are for 25, 50, 100, and 200 meter; therefore, 25 meters is the most conservative threshold distance. The emission thresholds were obtained based on the Central Orange County Source Receptor Area (SRA) 17. A daily disturbance value of 5 acres per day is assumed for construction based on SCAQMD guidance for determining daily disturbance area based on CalEEMod-estimated fleet (SCAQMD 2025). As previously noted, the Extended Stay America hotel is located approximately 75 feet from the project site. As such, the thresholds for a receptor distance of 25 meters (approximately 82 feet), the most conservative distance, is assumed to determine construction air quality impacts. The data provided Section 4.1: Air Quality
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in Table 4.1-5 shows that none of the analyzed criteria air pollutants would exceed the local emissions thresholds at the nearest sensitive receptor, the Extended Stay America hotel. Therefore, a less than significant local air quality impact would occur from construction.

Table 4.1-5. Local Construction Emissions at the Nearest Receptor Activity
On-Site Pollutant Emissions (pounds/day)
NOx CO PM10 PM2.5
Site Preparation and Clearing 7 8 3 1
Grading and Excavation 76 87 9 4
Drainage, Utilities, and Subgrade 54 61 7 3
Paving and Construction 12 20 3 1
Maximum Daily Emissions 76 87 9 4
SCAQMD Maximum Daily Localized Emissions Thresholds 183 1,253 13 7 Exceed Threshold? No No No No
Source: Appendix C of the Draft EIR.

Notes: CO = carbon monoxide; NOx = oxides of nitrogen; PM10 = particulate matter less than 10 microns in diameter; PM2.5 = particulate matter less than 2.5 microns in diameter; SOx = sulfur oxides; VOC = volatile organic compounds Toxic Air Contaminants
Construction
The greatest potential for TAC emissions during construction would be related to diesel particulate matter emissions associated with heavy equipment operations. Health effects to residents from TACs are generally described in terms of risk based on a 30-year exposure (SCAQMD 2017). Given the temporary and short-term construction schedule (approximately 2 to 3 years), the project would not result in a long-term (i.e., lifetime or 30-year) diesel particulate matter emissions as a result of project construction. Furthermore, total construction-based PM emissions (including diesel exhaust emissions) do not exceed any local or regional thresholds, as shown in Table 4.1-4 and Table 4.1-5. Therefore, impacts to sensitive receptors from TAC emissions during construction would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.1.4.3 Threshold AQ-4: Odors (Construction)
Impact Analysis
Land uses generally associated with odor complaints include agricultural uses (livestock and farming); wastewater treatment plants; food processing plants; chemical plants; composting operations; refineries; landfills; dairies; and fiberglass molding facilities (CARB 2005). The project does not propose or require any additional land uses typically associated with emitting objectionable odors. Potential odor sources associated with the project may result from Section 4.1: Air Quality
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construction equipment exhaust and the application of asphalt and architectural coatings during construction activities. Standard construction requirements would minimize odor impacts from construction. The construction odor emissions would be temporary, short-term, and intermittent in nature and would cease upon completion of the respective phase of construction. As shown in Table 4.1-5, emissions of sulfurous gases, the main source of odors from construction equipment, would be extremely limited during construction. Therefore, odors associated with the project construction would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.1.5 Cumulative Impacts
The following sections address various potential cumulative impacts relating to air quality that could result from implementation of the project.

4.1.5.1 Cumulative Threshold AQ-2: Cumulative Increase in Criteria Air Pollutant Emissions (Construction)
The thresholds in Table 4.1-4 indicate if a project would result in a cumulatively considerable contribution to the existing cumulative impact related to non-attainment of ozone and PM standards during construction. As such, the analysis for Threshold AQ-2 is cumulative in nature.

Similar to the project, other cumulative projects would be required to demonstrate consistency with SCAQMD thresholds to determine if the project would result in a cumulatively considerable impact related to ozone or PM. The combined cumulative development impacts would likely be significant. However, ss indicated under the analysis for Threshold AQ-2, construction-source air pollutant emissions would not exceed the regional thresholds for any criteria air pollutant. Thus, the project’s emissions during construction would be less-than-cumulatively considerable. After construction, the project would reduce cumulative air quality impacts by providing active transportation facilities that supports reducing air pollutant emissions related to vehicle miles traveled. The project impacts would not be cumulatively considerable.

4.1.5.2 Cumulative Threshold AQ-3: Sensitive Receptors (Construction) This analysis assumes active cumulative projects within a 1-mile radius of the project site, mainly the OCVIBE Project as described in Section 3.3, Assumptions Regarding Cumulative Impacts.

The types of projects listed include a variety of land use types, including housing, commercial/retail and hotel, and food establishment projects. These projects are at various stages of development and require individual analysis to determine air quality impacts to sensitive receptors. As discussed under Threshold AQ-3, the project would not result in localized impacts during construction, including at the nearest receptor distance. Therefore, it is unlikely that project on-site emissions would combine with emissions from a cumulative project to create a hotspot for Section 4.1: Air Quality
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any pollutant at existing or future sensitive receptors developed under cumulative projects.

Accordingly, construction of the project would not expose nearby sensitive receptors to substantial localized pollutant concentrations, and a cumulatively considerable impact would not occur.

4.1.5.3 Cumulative Threshold AQ-4: Odors (Construction) Impacts relative to objectionable odors are limited to the area immediately surrounding the odor source and are not cumulative in nature because the air emissions that cause odors disperse beyond the sources of the odor. As the emissions disperse, the odor becomes decreasingly detectable. Construction of cumulative projects would have the potential to occur simultaneously with the project. Constructionrelated odors would include construction equipment exhaust and the application of asphalt and architectural coatings. However, generator of odors in any one area would be temporary, short-term, and intermittent in nature, and odors from multiple construction sites would be unlikely to combine to contribute to any cumulatively considerable odor impacts in the local area. Thus, project-related odor impacts in combination with other cumulative projects would be less-than-cumulatively considerable.

4.1.6 Level of Significance Before Mitigation
The following thresholds would be less than significant:
• Threshold AQ-2: Project construction would not result in a cumulatively considerable net increase of any criteria air pollutant during construction for which the project region is non-attainment under an applicable federal or state ambient air quality standard. • Threshold AQ-3: Project construction would not expose sensitive receptors to substantial pollutant concentrations during construction. • Threshold AQ-4: Project construction would not result in other emissions (such as those leading to odors) adversely affecting a substantial number of people during construction.

4.1.7 Mitigation Measures
No mitigation measures are required.

4.1.8 Level of Significance After Mitigation
Not applicable.

Section 4.2: Biological Resources
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4.2 Biological Resources
This section evaluates the potential for impacts relating to biological resources resulting from implementation of OC River Walk Project (project).

The analysis in this section is based in part on the OC River Walk Project Biological Resources Technical Report prepared by Harris & Associates included in Appendix D of this Draft EIR.

4.2.1 Environmental Setting

4.2.1.1 Regulatory Setting
This section describes the federal, state, and local regulatory framework adopted to address biological resources.

Federal
Clean Water Act (U.S. Code, Title 33, Sections 1251–1376) The federal Clean Water Act (CWA) provides guidance for the restoration and maintenance of the chemical, physical, and biological integrity of the nation’s waters. Section 401 requires a project proponent to obtain a federal license or permit that allows activities resulting in a discharge to waters of the United States to obtain state certification, thereby ensuring that the discharge will comply with provisions of the CWA. The State Water Resources Control Board (SWRCB) administers the certification program in California. Section 402 establishes a permitting system for the discharge of any pollutant (except dredged or fill material) into waters of the United States.

Section 404 establishes a permit program administered by the U.S. Army Corps of Engineers (USACE) that regulates the discharge of dredged or fill material into waters of the United States, including wetlands.

Federal Endangered Species Act (U.S. Code, Title 16, Sections 1531–1543) The federal Endangered Species Act (FESA) and its subsequent amendments provide guidance for the conservation of endangered and threatened species and the ecosystems on which they depend.

In addition, FESA defines species as “threatened” or “endangered” and provides regulatory protection for listed species. FESA also provides a program for the conservation and recovery of threatened and endangered species and the conservation of designated critical habitat that the U.S.

Fish and Wildlife Service (USFWS) determines to be required for the survival and recovery of these listed species.

Migratory Bird Treaty Act (U.S. Code, Title 16, Sections 703–712) All migratory bird species that are native to the United States or its territories are protected under the federal Migratory Bird Treaty Act (MBTA), as amended under the Migratory Bird Treaty Section 4.2: Biological Resources
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Reform Act of 2004 (Senate Bill [SB] 2547). The MBTA is generally protective of migratory birds but does not actually stipulate the type of protection required. In common practice, the MBTA is now used to place restrictions on disturbance of active bird nests during the nesting season (generally February 1 to August 31). In addition, USFWS commonly places restrictions on disturbances allowed near active raptor nests.

Wetlands and Other Waters of the United States
Aquatic resources, including riparian areas, wetlands, and certain aquatic vegetation communities, are considered sensitive biological resources and can fall under the jurisdiction of several regulatory agencies. In accordance with the Navigable Waters Protection Rule, effective June 22, 2020, the USACE exerts jurisdiction over waters of the United States, including the territorial seas and traditional navigable waters; perennial and intermittent tributaries that contribute surface water flow to such waters; certain lakes, ponds, and impoundments of jurisdictional waters; and wetlands adjacent to other jurisdictional waters (33 CFR Part 328; 40 CFR Parts 110, 112, 116, 117, 120, 122, 230, 300, 302, and 401).

State
California Endangered Species Act (California Fish and Game Code, Section 2050 et seq.) The California Endangered Species Act (CESA) establishes the policy of the state to conserve, protect, restore, and enhance threatened or endangered species and their habitats. CESA mandates that state agencies should not approve projects that would jeopardize the continued existence of threatened or endangered species if reasonable and prudent alternatives are available that would avoid jeopardy. There are no state agency consultation procedures under CESA. For projects that would affect a listed species under both CESA and FESA, compliance with FESA would satisfy CESA if the California Department of Fish and Wildlife (CDFW) determines that the federal incidental take authorization is consistent with CESA under the California Fish and Game Code, Section 2080.1. For projects that would result in take of a species only listed under CESA, the project proponent must apply for a take permit under Section 2081(b).

California Environmental Quality Act Guidelines, Section 15380(b) Although threatened and endangered species are protected by specific federal and state statutes, California Environmental Quality Act (CEQA) Guidelines, Section 15380(b), provides that a species not listed on the federal or state list of protected species may be considered rare or endangered if the species can be shown to meet certain specified criteria. These criteria have been modeled after the rare or endangered species definition in FESA and Sections 2050 through 2059.26 of the California Fish and Game Code dealing with rare or endangered plants and wildlife.

This section was included in CEQA primarily to deal with situations in which a public agency is reviewing a project that may have a significant effect on, for example, a candidate species that has Section 4.2: Biological Resources
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not been listed by either the USFWS or CDFW. Thus, CEQA provides an agency with the ability to protect a species from the potential impacts of a project until the respective government agencies have an opportunity to designate the species as protected, if warranted. CEQA also calls for the protection of other locally or regionally significant resources, including natural communities.

Although natural communities do not currently have legal protection of any kind, CEQA calls for an assessment of if any such resources would be affected and requires findings of significance if there would be substantial losses. Natural communities listed as sensitive by the California Natural Diversity Database are considered by the CDFW to be significant resources and fall under the CEQA Guidelines to address impacts. Local planning documents, such as General Plans, often identify these resources as well.

California Fish and Game Code, Section 1602
Under this section of the California Fish and Game Code, the project proponent is required to notify the CDFW before the start of any project that would divert, obstruct, or change the natural flow, bed, channel, or bank of any river, stream, or lake. Pursuant to the California Fish and Game Code, a “stream” is defined as a body of water that flows at least periodically, or intermittently, through a bed or channel that has banks and supports fish or other aquatic life. Based on this definition, a watercourse with surface or subsurface flows that supports or has supported riparian vegetation is a stream and is subject to CDFW jurisdiction. Altered or artificial watercourses valuable to fish and wildlife are subject to CDFW jurisdiction. The CDFW also has jurisdiction over dry washes that carry water during storm events.

Preliminary notification and project review generally occur during the environmental process.

When an existing fish or wildlife resource may be substantially adversely affected, the CDFW is required to propose reasonable project changes to protect the resource. These modifications are formalized in a streambed alteration agreement, which becomes part of the plans, specifications, and bid documents for the project.

California Fish and Game Code, Sections 2080 and 2081
Section 2080 of the California Fish and Game Code states that “no person shall import into this state, export out of this state, or take, possess, purchase, or sell within this state, any species, or any part or product thereof, that the Commission [California Fish and Game Commission] determines to be an endangered species or threatened species, or attempt any of those acts, except as otherwise provided in this chapter, or the Native Plant Protection Act, or the California Desert Native Plants Act.” Pursuant to Section 2081 of the California Fish and Game Code, the CDFW may authorize individuals or public agencies to import, export, take, or possess state-listed endangered, threatened, or candidate species. These otherwise prohibited acts may be authorized through permits or Memoranda of Understanding if the take is incidental to an otherwise lawful activity, the impacts of the authorized take are minimized and fully mitigated, the permit is Section 4.2: Biological Resources
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consistent with any regulations adopted pursuant to any recovery plan for the species, and the project operator ensures adequate funding to implement the measures required by the CDFW.

California Fish and Game Code, Sections 3503, 3503.5, 3513, and 3800 Section 3503 of the California Fish and Game Code states that it is unlawful to take, possess, or needlessly destroy the nest or eggs of any bird. Section 3503.5 specifically states that it is unlawful to take, possess, or destroy any raptor (i.e., species in the orders Falconiformes and Strigiformes), including nests or eggs. Typical violations of the California Fish and Game Code include destruction of active nests resulting from removal of vegetation in which the nests are located.

Violation of Section 3503.5 could also include failure of active raptor nests resulting from disturbance of nesting pairs by nearby project construction. This statute does not provide for the issuance of any type of incidental take permit.

Section 3513 of the California Fish and Game Code upholds the MBTA by prohibiting any take or possession of birds that are designated by the MBTA as migratory nongame birds except as allowed by federal rules and regulations promulgated pursuant to the MBTA.

Section 3800 of the California Fish and Game Code affords protection to nongame birds, which are birds occurring naturally in California that are not resident game birds, migratory game birds, or fully protected birds.

California Fish and Game Code, Sections 3511, 4700, 5050, and 5515 California fully protected species are described in Sections 3511, 4700, 5050, and 5515 of the California Fish and Game Code. These statutes prohibit take or possession of fully protected species. The CDFW is unable to authorize incidental take of fully protected species when activities are proposed in areas inhabited by those species.

California Wetland Definition
Unlike the federal government, California has adopted the Cowardin et al. (1992) definition of “wetlands.” For this classification, wetlands must have one or more of the following three attributes: (1) at least periodically, the land supports predominantly hydrophytes (at least 50 percent of the aerial vegetative cover); (2) the substrate is predominantly undrained hydric soil; and (3) the substrate is non-soil and saturated with water or covered by shallow water at some time during the growing season of each year.

Under normal circumstances, the federal definition of wetlands requires all three wetland identification parameters to be met, whereas the Cowardin et al. (1992) definition requires the presence of at least one of these parameters. For this reason, identification of wetlands by state agencies consists of the union of all areas that are periodically inundated or saturated or in which at least seasonal dominance by hydrophytes may be documented or in which hydric soils are present.

Section 4.2: Biological Resources
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Natural Communities Conservation Planning Act (California Fish and Game Code, Section 2800)
The Natural Communities Conservation Planning (NCCP) program is a cooperative effort to protect habitats and species. It began under the state’s NCCP Act of 1991 and is broader in its orientation and objectives than CESA or FESA. These laws are designed to identify and protect individual species that have already declined significantly in number. The primary objective of the NCCP program is to conserve natural communities at the ecosystem level while accommodating compatible land use. The program seeks to anticipate and prevent the controversies and gridlock caused by species’ listings by focusing on the long-term stability of wildlife and plant communities and including key interests in the process.

This voluntary program allows the state to enter into planning agreements with landowners, local governments, and other stakeholders to prepare plans that identify the most important areas for a threatened or endangered species and the areas that may be less important. These NCCP Plans may become the basis for a state permit to take threatened and endangered species in exchange for conserving their habitat. The CDFW and USFWS worked to combine the NCCP program with the federal Habitat Conservation Plan process to provide take permits for state and federally listed species. Under the NCCP Act, local governments can take the lead in developing these NCCP Plans and become the recipients of state and federal take permits.

Native Plant Protection Act (California Fish and Game Code, Sections 1900–1913) California’s Native Plant Protection Act requires state agencies to use their authority to carry out programs to conserve endangered and rare native plants. Provisions of the act prohibit the take of listed plants from the wild and require notification to the CDFW at least 10 days in advance of any change in land use. This allows the CDFW to salvage listed plant species that would otherwise be destroyed. The project proponent is required to conduct botanical inventories and consult with the CDFW during project planning to comply with the provisions of the act and sections of CEQA that apply to rare or endangered plants.

Porter-Cologne Water Quality Control Act (California Water Code, Division 7) The SWRCB works in coordination with the nine Regional Water Quality Control Boards (RWQCBs) to preserve, protect, enhance, and restore water quality. Each RWQCB makes decisions related to water quality for its region and may approve, with or without conditions, or deny projects that could affect waters of the state. Their authority comes from the CWA and the state’s Porter-Cologne Water Quality Control Act (Porter-Cologne Act). The Porter-Cologne Act broadly defines “waters of the state” as “any surface water or groundwater, including saline waters, within the boundaries of the state” (California Water Code, Section 13050[e]).

Under the Porter-Cologne Act, the SWRCB and the nine RWQCBs also have the responsibility of granting CWA National Pollutant Discharge Elimination System permits and waste discharge Section 4.2: Biological Resources
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requirements for point-source and nonpoint-source discharges to waters. These regulations limit impacts on aquatic and riparian habitats from a variety of urban sources.

Local
County of Orange Central and Coastal Subregion Natural Communities Conservation Plan/Habitat Conservation Plan
The County of Orange Central and Coastal Subregion Natural Communities Conservation Plan/Habitat Conservation Plan (NCCP/HCP) was approved in 1996. It provides a planning framework for development projects within the program’s planning area to avoid, minimize, and compensate for impacts to wildlife (County of Orange 1996). The purpose of the NCCP/HCP is to sustain and restore species and their habitat identified by CDFW as necessary to maintain the continued viability of biological communities impacted by growth and development.

The City of Anaheim is enrolled in the NCCP/HCP. According to the City of Anaheim General Plan Green Element, a portion of the City, generally south of State Route (SR-) 91 and east of SR-55, falls within the NCCP/HCP boundary in the City of Anaheim (City of Anaheim 2004). The City of Orange is enrolled in the NCCP/HCP. A portion of the City near SR-241, SR-261, and Santiago Canyon Road falls within the NCCP/HCP boundary in the City of Orange (ARCGIS 2025). The project site is not within the boundaries of the NCCP/HCP. Therefore, the project is not subject to the requirements of the NCCP/HCP.

Cities of Anaheim and Orange General Plans
The project is in the Cities of Orange and Anaheim and, therefore, subject to the goals and policies of the City of Orange General Plan and the City of Anaheim General Plan.

City of Anaheim
The City of Anaheim General Plan element most applicable to biological resources includes the Green Element and applicable goals and policies are listed below:
• Goal 4.1: Maximize the recreational and scenic potential of existing reservoirs, basins and waterways.
− Policy 1: Support the County of Orange to continue in their efforts to upgrade and maintain the Santa Ana River Trail.
− Policy 2: Work with the County of Orange and the Orange County Water District to maintain and improve the recreational and scenic resources of the Anaheim Lakes and Five Coves areas and other appropriate water resource areas, including regarding basins and reservoirs.
• Goal 7.1: Reduce urban run-off from new and existing development.

Section 4.2: Biological Resources
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− Policy 1: Ensure compliance with the Federal Clean Water Act requirements for National Pollutant Discharge Elimination System (NPDES) permits, including developing and requiring the development of Water Quality Management Plans for all new development and significant redevelopment in the City. − Policy 2: Continue to implement an urban runoff reduction program consistent with regional and federal requirements, which includes requiring and encouraging the following:
 Increase permeable areas and install filtration controls (including grass lined swales and gravel beds) and divert flow to these permeable areas to allow more percolation of runoff into the ground;
 Use natural drainage, detention ponds or infiltration pits to collect runoff; and,
 Prevent rainfall from entering material and waste storage areas and pollution-laden surfaces.
− Policy 4: Require new development and significant redevelopment to utilize site preparation, grading and best management practices that provide erosion and sediment control to prevent construction-related contaminants from leaving the site and polluting waterways.
− Policy 5: Coordinate with appropriate Federal, State, and local resource agencies on development projects and construction activities affecting waterways and drainages.

City of Orange
The City of Orange General Plan element most applicable to biological resources includes the Natural Resources Element and applicable policies are listed below:
• Goal 1.0: Provide recreational use, scenic enjoyment, and the protection of natural resources and features in open space areas.
− Policy 1.1: Conserve open space through various public-private funding mechanisms and management strategies including, but not limited to, conservation easements.
− Policy 1.2: Actively seek out new public open space opportunities through land recycling.
− Policy 1.3: Promote development of additional open spaces and access points adjacent to waterways and planned trails.
• Goal 2.0: Protect air, water, and energy resources from pollution and overuse. − Policy 2.3: Reduce the amount of water used for landscaping through the use of native and drought-tolerant plants, proper soil preparation, and efficient irrigation systems as parks and other City facilities are built or renovated.

Section 4.2: Biological Resources
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− Policy 2.4: Encourage the production, distribution, and use of recycled and reclaimed water for landscaping projects, while maintaining urban runoff water quality objectives.
− Policy 2.6: Encourage sustainable building and site designs for new construction and renovation projects.
− Policy 2.8: Encourage development that incorporates pedestrian- and transitoriented design and landscape elements. − Policy 2.11: Protect the ecological integrity and overall health of Orange’s watersheds.
− Policy 2.12: Cooperate with water supply agencies to protect the quantity and quality of local groundwater supplies.
− Policy 2.13: Control surface runoff water discharges into the stormwater conveyance system to comply with the City’s National Pollutant Discharge Elimination System (NPDES) Municipal Permit and other regional permits issued by the Santa Ana Regional Water Quality Control Board. − Policy 2.14: Reduce pollutant runoff from new development by requiring use of the most low development impact practices and effective Best Management Practices (BMPs) currently available.
− Policy 2.15: Minimize the amount of impervious surfaces and associated urban runoff pollutants in new development and significant redevelopment throughout the community.
− Policy 2.16: Protect in-stream habitat and natural stream and channel features. • Goal 4.0: Conserve and protect wildlife habitat, plant and animal species of concern, and general biodiversity.
− Policy 4.1: Preserve and protect native and habitat-supporting plant resources throughout the City.
− Policy 4.3: Reduce the impact of urban development on important ecological and biological resources.
− Policy 4.4: Repair or improve ecological and biological conditions in the urban and natural environments when reviewing proposals for site development and redevelopment, as well as public improvements.
− Policy 4.5: Protect the Santiago Creek and Santa Ana River corridors from premature urbanization to ensure the continued availability of important sand and gravel, flood control, water recharge, biological, and open space resources. • Goal 5.0: Provide recreational facilities and programs that adequately serve the needs of residents.

Section 4.2: Biological Resources
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− Policy 5.4: Develop new public parks and open space resources by establishing incentives to use creative techniques available to property owners and developers that support public-private open space partnerships. − Policy 5.5: Explore and pursue new approaches to new park development and to providing a balanced mix of amenities and facilities.

4.2.1.2 Existing Conditions
A Biological Resources Technical Report (BRTR) was prepared by Harris & Associates in July 2023 and is included as Appendix D to this Draft EIR. As part of the BRTR, a general biological reconnaissance survey and a formal aquatic resources delineation survey were conducted on May 16, 2023. During the survey, the biologists mapped vegetation communities, documented observed plant and wildlife species, and evaluated the potential for occurrence of sensitive plant and wildlife species by walking slowly along the meandering transects throughout the survey area. No in-water surveys were conducted. An Aquatic Resources Delineation Report (ARDR) was prepared in 2023 and is included as an appendix in the BRTR. Based on the lack of suitable habitat, no focused or protocol wildlife surveys or rare plant surveys were conducted during this survey effort.

Topography and Soils
The project site is in a relatively flat urban setting, with the greatest elevation decreases occurring in the Santa Ana River corridor, Burris Basin, and Former Ball Road Basin. The on-site elevation ranges from approximately 133 to 190 feet above mean sea level. The project site is underlain by three soil types: Metz loamy sand (zero to 2 percent slopes), Pits (zero to 5 percent slopes), and Riverwash (refer to Appendix D, Figure 4, Soils). The northeastern corner of the survey area that cannot be characterized by soil type is water. Metz loamy sand occurs along the eastern edge of the project site and consists of somewhat excessively drained soils that formed in alluvial material from mixed, but dominantly sedimentary rocks, typically found in alluvial fans and floodplains. Pits constitutes a small portion in the northwestern corner of the project site and consists of poorly drained soils that formed in fine-textured alluvium weathered from igneous rocks that are found on floodplains and in basins. Riverwash represents the majority of the survey area and consists of very recent depositions of gravel, sand, and silt alluvium along major streams and their tributaries (USDA 2019). The Riverwash and Pits soil types that occur on the project site are classified as hydric (wetland) soils and have the potential to contain hydric inclusions (USDA 2019).

Hydrology
The project site is in the Santa Ana River Watershed (Hydrologic Unit 18070203) (USGS 2025).

The Santa Ana River Watershed is the largest in Southern California and encompasses 2,840 square miles within portions of Riverside and Orange Counties and a small part of eastern Los Angeles County (USGS 2025). The total length of the Santa Ana River and the streams that drain Section 4.2: Biological Resources
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into it is approximately 700 miles, starting from its northernmost reaches at the crest of the San Bernardino Mountains out to the coast near Huntington Beach. This network of waterways includes features that are both natural and channelized in concrete. The Santa Ana River is defined by the U.S. Army Corps of Engineers (USACE) as a traditional navigable water (USACE 2025).

Portions of the Santa Ana River are on the CWA Section 303(d) List for impaired waters; however, the reach in the survey area is not listed as impaired (SWRCB 2025).

The portion of the Santa Ana River within the survey area also contains the USACE constructed Santa Ana River 1 Levee System (SAR1 Levee System) (Upstream Reach) (USACE 2015). The National Wetlands Inventory (NWI) results identify several mapped aquatic features in the survey area (Figure 4.2-1, National Wetlands Inventory Results) (USFWS 2021). The Santa Ana River within the boundary of the project site is identified as a lake but is more accurately characterized as having a lacustrine system,
1 as is also Burris Basin in the northwestern portion
of the survey area (NWI 2025). The Former Ball Road Basin, west of the Santa Ana River and south of Burris Basin, is identified on the NWI results as both freshwater emergent wetland and freshwater pond. One riverine feature (Collin’s Channel) is identified connecting to the east side of the Santa Ana River in the central portion of the survey area. No other aquatic features are identified in the survey area by the NWI results.

Based on a review of the U.S. Geological Survey (USGS) National Hydrography Dataset (NHD), the survey area contains several mapped aquatic resources, including those that have hydrologic connections to the Santa Ana River (USGS 2025). The Santa Ana River is identified as a stream/river with an artificial path, likely because of the concrete channelization of the river and construction of the SAR1 Levee System (Upstream Reach). Both basins are identified as reservoirs with intermittent connections to each other and the Santa Ana River. Collin’s Channel is identified as a canal/ditch that is connected to the Santa Ana River from the east. No other aquatic features are identified in the survey area by the USGS NHD results.

Vegetation Communities and Land Cover Types
The project site is located along the Santa Ana River corridor, generally between Orangewood Avenue and Ball Road, extending to the existing Anaheim Coves at Burris Basin. It generally encompasses approximately a 2-mile stretch of the Santa Ana River, covering approximately 111 acres. The existing land uses and associated acreage on the project site are described in Table 4.2-1, Existing Land Use Acreages.
1 The lacustrine system includes wetlands and deepwater habitats with all of the following characteristics: (1) situated in a topographic depression or a dammed river channel; (2) lacking trees, shrubs, persistent emergents, and emergent mosses or lichens with 30 percent or greater areal coverage; and (3) total area of at least 8 hectares (ha) (20 acres) (NMI 2025).

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Table 4.2-1. Existing Land Use Acreages
Land Use Acres
Aquatic area (including rivers/creeks/open water) 77.81 Urban/commercial land (including roads) 28
Vegetated land 5.07
Total 110.88
Notes: Acreages rounded to one-hundredth of an acre.

As shown in Table 4.2-2, Vegetation Communities and Land Cover Types, the entire survey area comprises 110.88 acres of the project site (approximately 111 acres) plus 51.01 acres of survey buffer area, for a total of 161.89 acres. The entire survey area contains a total of nine vegetation community types: freshwater, emergent wetland, non-vegetated channel, Diegan coastal sage scrub, mule fat scrub (disturbed), southern willow scrub, non-native woodland, disturbed habitat, and developed land, as shown on Figure 4.2-2, Vegetation Communities and Land Cover Types.

Table 4.2-2. Vegetation Communities and Land Cover Types Vegetation Community and
Land Cover Type Project Site (acres)1 Survey Buffer (acres)1 Survey Area (acres)1 Aquatic
Fresh water2 3.48 3.15 6.63
Freshwater emergent wetland2 0 0.97 0.97
Non-vegetated channel2 74.33 1.95 76.28
Subtotal 77.81 6.07 83.88
Scrub and Riparian Scrub
Diegan coastal sage scrub2 0.21 0.95 1.16
Mule fat scrub (disturbed)2 0.38 0 0.38
Southern willow scrub2 0.66 0.97 1.63
Subtotal 1.25 1.92 3.17
Woodland and Forest
Non-native woodland 0.22 0 0.22
Disturbed/Developed
Disturbed habitat 3.60 2.75 6.35
Developed land 28 40.27 68.27
Subtotal 31.60 43.02 74.62
Total 110.88 51.01 161.89
Sources: CDFW 2025c; Holland 1986.

Notes:
1 Acreages rounded up to one-hundredth.
2 Considered a sensitive vegetation community by the CDFW.

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Aquatic Communities
The aquatic vegetation community types within the survey area are shown on Figure 4.2-2 and described below.

Fresh Water: Fresh water includes year-round bodies of fresh water in the form of lakes, streams, ponds, or rivers. Fresh water includes those portions of water bodies that are usually covered by water and contain less than 10 percent vegetated cover (Holland 1986). A total of approximately

6.63 acres of fresh water was documented, with 3.48 acres occurring on the project site and the remaining 3.15 acres in the survey buffer. Fresh water in the survey area occurs within Burris Basin, the Former Ball Road Basin, The Islands Golf Center, and the Orange County Water District (OCWD)-owned and -operated water distribution plant in the northwestern portion of the survey area. Both basins have direct surface water connectivity to the Santa Ana River, directly east of the basins.

Freshwater Emergent Wetland: Freshwater emergent wetlands are dominated by low-growing perennial wetland species. These can be found in channels, seeps and springs, floodplains, margins of lakes and rivers, and various basins such as pools and ponds, palustrine lakes, montane meadows, and dune swales. A total of approximately 0.97 acre of freshwater emergent wetland was documented within the survey buffer area but none on the project site.

Non-Vegetated Channel: Non-vegetated channel consists of predominantly sandy, gravelly, or rocky channels lacking or with reduced vegetation. Variable water lines inhibit the growth of vegetation, although some weedy species of grasses may grow along the outer edges of the channel. Vegetation may exist here but is usually less than 10 percent of the total cover (Holland 1986). Non-vegetated channel comprises the majority of the survey area. A total of approximately

76.28 acres of non-vegetated channel was documented, with 74.33 acres occurring on the project site and the remaining 1.95 acres in the survey buffer. The Santa Ana River and Collin’s Channel are both defined as non-vegetated channels. The extent of the Santa Ana River that runs northeast to southwest through much of the survey area is a fully concrete- and riprap-lined channel and does not support any vegetation. Collin’s Channel is a riprap- and concrete-lined channel that enters the eastern edge of the survey area and connects to the eastern side of the Santa Ana River.

Sparse grasses and weeds were observed growing through the rock riprap in Collin’s Channel; however, no substantial vegetation community was observed in the channel during the survey.

Scrub and Riparian Scrub Communities
Diegan Coastal Sage Scrub: A total of approximately 1.16 acres of Diegan coastal sage scrub was documented, with 0.21 acre occurring on the project site and 0.95 acre in the survey buffer. Diegan coastal sage scrub was observed in the northwest corner of the survey area, bordering the Burris Basin, The Islands Golf Center, and the OCWD facilities. The Diegan coastal sage scrub in the survey area appears to be part of restoration efforts and shows evidence of purposefully planted Section 4.2: Biological Resources
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(installed) vegetation. Dominant species in the Diegan coastal sage scrub include California sagebrush, California buckwheat, Cleveland sage (Salvia clevelandii), and mule fat.

Mule Fat Scrub (Disturbed): Approximately 0.38 acre of mule fat scrub (disturbed) occurs on the project site, along the southwest shoreline of Burris Basin in the northwestern portion of the survey area. No mule fat scrub was documented in the survey buffer. This habitat is relatively sparse, with patchy coverage of mule fat and has encroachment of black mustard (Brassica nigra) from nearby disturbed areas.

Southern Willow Scrub: A total of approximately 1.63 acre of southern willow scrub was documented, with 0.66 acre occurring in the northwestern portion of the project site and 0.97 acre in the western edge of the survey buffer. The 0.66 acre of southern willow scrub on the project site is within and along the western shore of Burris Basin. This area is dominated by Goodding’s willow, with mule fat and a small stand of bulrush (Typha sp.) in the understory. The 0.97 acre of southern willow scrub along the western edge of the survey buffer within the Former Ball Road Basin is densely vegetated with Goodding’s willow with mule fat and black mustard (Brassica nigra) in the understory and outer edges.

Woodland and Forest Communities
Non-Native Woodland: Approximately 0.22 acre of non-native woodland occurs on the project site, in a narrow stand between The Islands Golf Center putting green and Burris Basin in the northwestern portion of the survey are). This area is dominated by arundo and tamarisk, with a small number of young Goodding’s willows in the northern edge bordering the southern willow scrub to the northwest.

Disturbed/Developed Land Cover Types
Disturbed Habitat: A total of approximately 6.35 acres of disturbed habitat was documented, with

3.60 acres occurring on the project site and 2.75 acres in the survey area. Disturbed habitat was documented bordering the western, southern, and southeastern edges of Burris Basin and the northern and eastern edges of the Former Ball Road Basin in the northern portion of the survey area, as well as along the northeastern edge of the Santa Ana River. Alteration of these areas from apparent mechanical disturbance was observed. These areas are dominated by black mustard, star thistle (Centaurea calcitrapa), and fountain grass (Pennisetum sp.), with patches of bare dirt throughout.

Developed Land: A total of approximately 68.27 acres of developed land was documented, with 28 acres occurring on the project site and 40.27 acres in the buffer survey area. The developed land in the survey area is the second most prevalent land cover type in the survey area, after non-vegetated channel. In the survey area, developed land includes roadways, parking lots, Section 4.2: Biological Resources
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concrete sidewalks and bike paths, commercial and industrial buildings, The Islands Golf Center putting green, and areas of ornamental landscaping and decorative hardscape.

Jurisdictional Aquatic Resources
The results of the 2023 ARDR determined that a total of 84.54 acres of non-wetland waters occur in the survey area that are potentially under the jurisdiction of the USACE, RWQCB, and CDFW, pursuant to Sections 404 and 401 of the CWA and Section 1602 of the California Fish and Game Code. In addition, the reach of the Santa Ana River in the survey area contains the Santa Ana River 1 Levee System (Upstream Reach) and therefore is potentially under the jurisdiction of the USACE pursuant to the Rivers and Harbors Act Section 408.

Of the total 84.54 acres of aquatic resources documented in the survey area, 78.47 acres occur on the project site. These include aquatic and riparian vegetation communities (i.e., fresh water, non-vegetated channel, freshwater emergent wetland, and southern willow scrub) that occur in the survey area, which may fall under the regulatory jurisdiction of the USFWS, RWQCB, or CDFW (refer to Figure 4.2-3, Aquatic Resources). The regulatory agencies categorize aquatic resources into two types of ‘waters’: wetland waters (i.e., delineated areas that contain hydrophytic plants, hydric soils, and wetland hydrology) and non-wetland waters (i.e., delineated areas that do not meet the criteria for wetlands, as previously defined). In the survey area, freshwater emergent wetland is considered a wetland water, while fresh water and non-vegetated channel are considered non-wetland waters.

Potentially jurisdictional aquatic resources mapped in the survey area are shown on Figure 4.2-3.

Table 4.2-3, Jurisdictional Aquatic Resources, provides a summary of these aquatic resources potentially under the jurisdiction of the USACE, RWQCB, and CDFW.

Table 4.2-3. Jurisdictional Aquatic Resources
Feature Project Site (acres) Survey Buffer (acres) Jurisdiction Santa Ana River 74.33 1.63 USACE1/RWQCB/CDFW
Collin’s Channel <0.01 0.32 USACE/RWQCB/CDFW
Burris Basin 3.48 3.15 USACE/RWQCB/CDFW
Burris Basin southern willow scrub 0.66 0.97 USACE/RWQCB/CDFW Former Ball Road Basin (including
freshwater emergent wetland)
0 0.97 USACE/RWQCB/CDFW
Total2 78.47 7.04 —
Notes: CDFW = California Department of Fish and Wildlife; RWQCB = Regional Water Quality Control Board; USACE = U.S. Army Corps of Engineers
1 Potentially subject to both the CWA Section 404 and Rivers and Harbors Act Section 408. 2 Total rounded to one-hundredth of an acre.

Sensitive Species
Sensitive species are those recognized by federal, state, or local agencies as being potentially vulnerable to impacts because of rarity, local or regional reductions in population numbers, Section 4.2: Biological Resources
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isolation/restricted genetic flow, or other factors. Special-status plants include those listed as threatened or endangered, proposed for listing, or candidates for listing by the USFWS and CDFW; those considered sensitive by the CDFW; those species included in the California Rare Plant Rank (CRPR) inventory maintained by the CNPS. Sensitive wildlife species include those listed as threatened or endangered, proposed for listing, or candidates for listing by the USFWS and CDFW; those considered sensitive by the CDFW; California Watch List (WL).

The list of potentially occurring sensitive plant and wildlife species is provided in Table 4.2-4, Sensitive Plant and Wildlife Species with Potential to Occur, along with an assessment of their potential for occurrence in the survey area. For the purposes of this biological resources analysis, those species that are known to occur or have some potential to occur within 1 mile of the survey area are included.

Table 4.2-4. Sensitive Plant and Wildlife Species with Potential to Occur Scientific
Name Common Name
Status
Federal/Stat
e/CRPR Habitat Potential to Occur
Plants
Abronia
villosa var.
aurita
Chaparral sandverbenaNone/None/
1B.1
Occurs in sandy soils in
coastal sage scrub, chaparral,
and desert dune habitats at
elevations between 245 and
5,250 feet above mean sea
level (amsl). Blooms January
to September.

Not Expected. The survey area is out of
elevation range for this species. Diegan
coastal sage scrub is present only in
northwestern portion; however, it is likely
a planted restoration area. A historical
location (from 1924) in the Santa Ana
River exists; however, this occurrence is
likely extirpated (Appendix D, Figure 8,
Sensitive Species with Potential to
Occur) (CDFW 2025b; Calflora 2025).

Eriastrum
densifolium
ssp.
sanctorum
Santa Ana River
woollystar
FE/SE/1B.1 Occurs in sandy or gravelly
soils in chaparral and coastal
sage scrub at elevations
between 300 and 2,000 feet
amsl. Blooms April through
September.

Not Expected. The survey area is out of
elevation range for this species. Diegan
coastal sage scrub is present only in
northwestern portion; however, it is likely
a planted restoration area. A historical
location exists; however, this occurrence
is documented within the Orange County
Quadrangle, and the exact location is not
known (CDFW 2025b; CNPS 2025).

Section 4.2: Biological Resources
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Table 4.2-4. Sensitive Plant and Wildlife Species with Potential to Occur Scientific
Name Common Name
Status
Federal/Stat
e/CRPR Habitat Potential to Occur
Wildlife
Fish
Oncorhynchu
s mykiss
irideus
(Southern
California
Distinct
Population
Segment)
Southern
California
steelhead
FE/SSC/Non
e
Occurs in cool, well
oxygenated freshwater
streams, primarily in the
upper watersheds of most
rivers year-round.

Not Expected. The Santa Ana River, the
only potentially suitable habitat, is
completely concrete lined, with concrete
spillways making fish passage unlikely.

Water levels are too low for fish
passage, and mechanical disturbance is
currently preventing higher potential for
likelihood. A historical location within 1
mile of the survey area exists; however,
the point is not specific but mapped to
the quadrangle and therefore could be
farther away than 1 mile (Appendix D,
Figure 8) (CDFW 2025b).

Reptiles
Phrynosoma
blainvillii
Blainville’s
horned lizard
None/SSC/N
one
Occurs in open areas of
sandy soil and low vegetation
in foothills, valleys, and semiarid mountains in grasslands coniferous forests,
woodlands, and chaparral.

Also found in lowlands within
sandy washes with scattered
shrubs and long dirt roads.

Not Expected. No suitable habitat is
present in the survey area. A historical
location within 1 mile of the survey area
exists but is not known in the survey area
(Appendix D, Figure 8) (CDFW 2025b).

Birds
Falco
peregrinus
anatum
American
Peregrine falcon
None/FP,
BCC/None
Occurs in open landscapes
with cliffs (or skyscrapers) for
nest sites, as well as along
rivers and coastlines or in
cities.

High Foraging. Not Expected Nesting.

High potential exists for the species to be
observed foraging in the survey area,
however, no suitable nesting habitat is
present. A historical location within 1 mile
of the survey area exists but is not known
in the survey area (Appendix D, Figure 8)
(CDFW 2025b).

Laterallus
jamaicensis
ssp.
coturniculus
California black
rail
FP/ST/None Occurs in tidal salt marshes
or grassy marshes with dense
strands of grasses, rushes,
and sedges for nesting.

Low Foraging. Not Expected Nesting.

Suitable foraging habitat is limited to the
small wetland areas in Burris Basin and
the Former Ball Road Basin. No suitable
nesting habitat is present in the survey
area. A historical location (from 1986) in
the Santa Ana River exists; however, this
occurrence is likely extirpated (Appendix
D, Figure 8) (CDFW 2025b; Calflora
2025).

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Table 4.2-4. Sensitive Plant and Wildlife Species with Potential to Occur Scientific
Name Common Name
Status
Federal/Stat
e/CRPR Habitat Potential to Occur
Pelecanus
erythrorhync
hos
American
white pelican

BCC/SSC/N
one
Occurs in coastal bays,
inlets, estuaries, and
sloughs and inland
freshwater lakes. Nests on
isolated islands in
freshwater lakes or
ephemeral islands in
shallow wetlands. Breeding
range in California is limited
to the northeastern corner
of the state.

Present. High Foraging, Not Expected
Nesting. Observed in the Santa Ana
River in the northern portion of the
survey area (Appendix D, Figure 9,
Sensitive Species Observed). Suitable
foraging habitat occurs in the Santa
Ana River, Burris Basin, and the
Former Ball Road Basin. No suitable
nesting habitat occurs in the survey
area.

Phalacrocor
ax auritus
(nesting
colony)
Double-crested
cormorant
None/WL/N
one
Occurs in salt and
freshwater habitats. Nests
on the ground, on cliff
edges, trees, shrubs, and in
artificial surfaces on and
near Channel Islands and
coast lines and lakes
elsewhere in the United
States.

Present. High Foraging, Moderate
Nesting. Observed during 2023 survey
foraging in the Santa Ana River and
sunning on sediment piles in the river
channel in the northern survey area
(Appendix D, Figure 9). Suitable
foraging habitat occurs in the Santa
Ana River and Burris Basin. Suitable
nesting habitat is present, but lower
likelihood to nest due to high levels of
human activity and frequent
disturbance.

Setophaga
petechial
Yellow warbler None/SSC/
None
Nests in well-developed
riparian woodlands and
montane scrub.

Present. High Foraging, Moderate
Nesting. Observed in the southern
willow scrub in the Former Ball Road
Basin (Appendix D, Figure 9). No
nests were observed directly. Suitable
southern willow scrub is limited to
Burris Basin and the Former Ball Road
Basin in the survey area, which
provide suitable foraging and
moderate quality, limited nesting
habitat. No historical locations for this
species occur in the survey area.

Sternula
antillarum
browni
California least
tern
FE,
FP/SE/None
Nests on open sandy dunes
and flats lacking vegetation in
colonies along California
coastlines in lagoons, bays,
and estuaries.

Low Foraging. Not Expected Nesting.

Low potential exists for the species to be
observed foraging in the Santa Ana River
in the survey area because of the far
distance to nesting habitat. Not expected
for nesting within the survey area, and no
established colony has been
documented in the survey area.

Historical locations within 1 mile of the
survey area exists but are not known in
the survey area (Appendix D, Figure 8)
(CDFW 2025b).

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Table 4.2-4. Sensitive Plant and Wildlife Species with Potential to Occur Scientific
Name Common Name
Status
Federal/Stat
e/CRPR Habitat Potential to Occur
Vireo belli
pusillus
Least Bell’s
vireo
FE/SE/None Occurs in riparian scrub
and riparian forest and is a
summer resident in
Southern California below
2,000 feet.

Present. High Foraging, Moderate
Nesting. At least one individual was
observed in the southern willow scrub
in the Former Ball Road Basin
(Appendix D, Figure 9). No nests were
observed directly. Suitable southern
willow scrub is limited to Burris Basin
and the Former Ball Road Basin in the
survey area, which provides suitable
foraging and moderate quality nesting
habitat. No historical locations for this
species occur in the survey area.

Mammals
Eumops
perotis
californicus
Western mastiff
bat
None/SSC/N
one
Occurs in open, semi-arid
woodlands, coastal scrub,
grasslands, palm oases,
chaparral, desert scrub, and
urban habitats with abundant
roosting locations.

Low Roosting; High Foraging. An
abundance of overpasses, bridges, and
buildings provide crevices suitable for
temporary roosting during foraging.

Foraging habitat is present above the
open water in the Santa Ana River and
Burris Basin. A historical location within
1 mile of the survey area exists, but
none are known in the survey area
(Appendix D, Figure 8) (CDFW 2025b).

Notes: BCC = Bird of Conservation Concern; FC = federal candidate; FP = federally protected; FE = federally endangered; FT = federally threatened; SE = state endangered; None = No status indicated for species; SE = state endangered; SSC = state species of special concern; WL = state watch list
CNPS CRPR Rare Plant Ranking: 1B = rare, threatened, or endangered in California and elsewhere; 2B = rare, threatened, or endangered in California but more common elsewhere; 3 = a watch list of species about which more information is needed; 4 = a watch list of species of limited distribution
Bold text: Species observed within the survey area.

Critical Habitat
There is no critical habitat for sensitive plant or wildlife species in or within 1 mile of the survey area (CDFW 2025a, 2025b; USFWS 2025b).

Sensitive Plant Species Observed
No sensitive plant species were observed during the survey. The list of plant species observed in the survey area during the biological resources survey is included in Appendix B of the BRTR (refer to Appendix D of the Draft EIR). A total of 34 plant taxa were observed on the project site, 19 (56 percent) of which were native and 15 (44 percent) of which were non-native.

Sensitive Wildlife Species Observed
A total of 48 wildlife species, including five invertebrates, three fish, one amphibian, one reptile, 36 birds, and two mammals, were observed in the survey area during the biological resources Section 4.2: Biological Resources
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survey. Of the 48 wildlife species observed in the survey area, the following four species are designated as sensitive:
• American white pelican (Pelecanus erythrorhynchos)
• Double-crested cormorant (Phalacrocorax auritus)
• Least Bell’s vireo (Vireo bellii pusillus)
• Yellow warbler (Setophaga petechia)
These sensitive wildlife species observed in the survey area are shown on Figure 9, Sensitive Species Observed, of the BRTR included as Appendix D to this Draft EIR.

American White Pelican (Pelecanus erythrorhynchos), BCC, SSC: An American white pelican was observed foraging in the Santa Ana River in the northern portion of the survey area during the 2023 biological survey (Appendix D, Figure 9). Suitable foraging habitat occurs in the Santa Ana River and Burris Basin in the northwestern portion of the survey area. No suitable nesting habitat occurs in the survey area, and no known nesting sites have been documented in or surrounding the survey area (Shuford and Gardali 2008).

Double-Crested Cormorant (Phalacrocorax auritus), WL: Double-crested cormorants were observed foraging in the Santa Ana River and perching on the sediment piles in the center of the river channel in the northern portion of the survey area during biological surveys. Suitable foraging habitat occurs in the Santa Ana River and Burris Basin in the northwestern portion of the survey area. No suitable nesting habitat occurs in the survey area.

Least Bell’s Vireo (Vireo bellii pusillus), FE, SE: Least Bell’s vireo was observed calling in the survey buffer, outside the project site, in the southern willow scrub in in the Former Ball Road Basin during the 2023 survey. The suitable nesting and foraging habitat for least Bell’s vireo in the survey area is limited to the small stands of southern willow scrub in Burris Basin and the Former Ball Road Basin. There is potential for the species to move between the two stands of southern willow scrub over Ball Road and through the concrete box culvert that runs under the road connecting the two basins. No least Bell’s vireo nests were observed during the survey.

Yellow Warbler (Setophaga petechial), SSC: Yellow warbler was observed in the survey buffer, outside the project site, in the southern willow scrub in the Former Ball Road Basin during the 2023 survey. The suitable nesting and foraging habitat for yellow warbler in the survey area is limited to the small stands of southern willow scrub in Burris Basin and the Former Ball Road Basin. The potential for this species to nest in the survey area is low because the available southern willow scrub does not have a well-developed canopy and is disturbed from apparent OCWD maintenance and the presence of unhoused encampments. Similar to least Bell’s vireo, there is potential for the species to move between the two stands of southern willow scrub in the basins. No nests were observed during the survey.

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Sensitive Wildlife Species Not Observed with a High Potential to Occur Based on the literature and database review, six sensitive wildlife species were considered for their potential to occur in the survey area but were not observed during the biological resources surveys (refer to Table 4.2-4). Two sensitive wildlife species, including American peregrine falcon (Falco peregrinus anatum) and western mastiff bat (Eumops perotis californicus), were determined to have a high potential to occur in the survey area but were not observed during the biological resource survey. These sensitive wildlife species with high potential to occur are shown on Figure 8, Sensitive Species with Potential to Occur, of the BRTR included as Appendix D to this Draft EIR.

American Peregrine Falcon (Falco peregrinus anatum), FDL, BCC/SDL: Suitable foraging habitat and prey is present in the Santa Ana River and Burris Basin and the Former Ball Road Basin in the survey area. However, no cliffs or high skyscrapers and bridges suitable for nesting are present in the survey area. One historical location for American peregrine falcon exists within 1 mile of the survey area, however, this species is not known to occur in the survey area (Appendix D, Figure 8, Sensitive Species with Potential to Occur) (CDFW 2025b).

Western Mastiff Bat (Eumops perotis californicus), SSC: Western mastiff bat, a CDFW Species of Special Concern, is North America’s largest bat, with a long tail, dark gray fur, long narrow wings, and large ears that are oriented forward and joined at the midline above the forehead. Western mastiff bat typically roosts colonially in rock crevices on the face of steep rocky cliffs, rock outcrops, and abandoned quarries. This species has been known to occasionally roost in buildings and palm trees; however, roosting in these structures appears to occur temporarily during migration. Western mastiff bat forages primarily on large moths, also eating other insects including beetles, crickets, bees, dragonflies, cicadas, and plant bugs. This species forages over open habitats, including meadows, grasslands, ponds, reservoirs, bays, riparian zones, sometimes in urban environments opportunistically while traveling between higher quality habitats. Threats to this species include loss and fragmentation of rocky habitat through mining, water impoundments, and road construction, as well as poisoning from pesticide use.

Suitable foraging habitat is present above the open water in the Santa Ana River and Burris Basin and the narrow riparian fringes around Burris Basin and the Former Ball Road Basin. The survey area offers an abundance of overpasses, bridges, and buildings with crevices suitable for temporary roosting by the western mastiff bat during foraging. A historical location for this species exists within 1 mile of the survey area, but none are known in the survey area (Appendix D, Figure 8) (CDFW 2025b).

Nesting Birds
The survey area contains suitable nesting habitat for several bird and raptor species protected under the California Fish and Game Code and MBTA. The majority of the survey area is developed, and specific to the Santa Ana River, lined with concrete and riprap, devoid of vegetation suitable for Section 4.2: Biological Resources
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most nesting birds and raptors. However, the survey area, particularly the Santa Ana River corridor, contains large expanses of open areas over slowly moving water suitable for insect- and aquatic-foraging bird species that may be attracted to the area for feeding and, therefore, may have higher potential to be found nesting within the survey area. The highest-quality suitable nesting habitat for riparian species occurs in the northwestern portion of the survey area, specifically the southern willow scrub, non-native woodland, disturbed mule fat scrub along the fresh open water of Burris Basin, and within the emergent wetland and southern willow scrub in the Former Ball Road Basin. Suitable nesting habitat for cavity nesters is present in the trees, both native and ornamental, and structures throughout and surrounding the survey area. A large amount of avian activity was observed in the southern willow scrub of the Former Ball Road Basin, including redwinged blackbirds (Agelaius phoeniceus), a yellow warbler, and a least Bell’s vireo. The ripraplined banks of the Santa Ana River channel and the shores of Burris Basin and the Former Ball Road Basin also serve as suitable nesting habitat for ground-nesting shorebirds, such as killdeer (Charadrius vociferus), of which many were observed perching on the deposited sediment “islands” and banks in the river channel during the 2023 surveys. Forster’s terns (Sterna forsteri) were observed hunting mosquitofish within the Santa Ana River channel and could be using the deposited sediment islands or other shoreline habitats in the survey area for nesting. Additionally, human-made infrastructure, such as light posts, building ledges, and overpasses provide potential nesting habitat for birds and raptors. Large colonies of cliff swallows (Petrochelidon pyrrhonota) were observed nesting under the Ball Road overpass in the survey area. Nesting materials were observed on parking lot light posts immediately west of the survey area in the Honda Center parking lot and were likely used by nesting osprey (Pandion haliaetus) hunting in the Santa Ana River corridor or the basins.

Roosting Bats
The survey area contains suitable roosting and foraging habitat for both common and sensitive bat species. Several concrete bridge overpasses span the width of the Santa Ana River channel and provide crevices suitable for structure-dwelling bats, including Mexican long-tongued bat (Choeronycteris mexicana) and big brown bat (Eptesicus fuscus). Ornamental and native tree species present on either side of the river channel also provide suitable roosting habitat for treeroosting bats, such as such as the hoary bat (Lasiurus cinereus), western red bat (Lasiurus blossevillii), and western yellow bat (Lasiurus xanthinus). Further, these potential roosting sites are within proximity to open water where bats that forage on insects over sources of open water, such as the western mastiff bat. No bats were observed using the survey area for roosting or foraging during the biological resource surveys. However, the availability of suitable habitat indicates bats are likely roosting and foraging in the survey area.

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Wildlife Corridors and Habitat Linkages
Wildlife corridors provide routes for local movement and also regional linkages and corridors, often following linear topographic, vegetation, or water features. These corridors can be continuous habitats features or “steppingstone” areas, providing critical rest and foraging areas for, for example, birds traveling along migratory routes. Local routes of movement provide constant connections to resources that include sources of water, home/cover sites, and foraging areas. Regional linkages and movement corridors provide larger patches of open space to allow relatively free movement of wildlife species along multiple paths between important resources.

These areas allow for not only long-term genetic flow between subpopulations but also critical pathways of seasonal/migratory movements. Larger predatory mammals often use regional corridors for hunting and reproduction needs. Potential wildlife corridors can include streams, riparian areas, and culverts under roadways. Habitat characteristics considered in the 2023 survey included topography, habitat quality, and adjacent land uses.

The survey area is likely to be used as a wildlife movement corridor and provides suitable nesting, foraging, and dispersal areas primarily for highly mobile species like bats and birds, and some movement opportunities for mammals. The area surrounding the survey area consists of dense urban development which restricts movement for many small mammals, amphibians, and reptiles. Mesocarnivores and medium-sized mammals, such as raccoon (Procyon lotor), coyote (Canis latrans), or bobcat (Lynx rufus), have some potential to use the access roads that border the Santa Ana River channel for movement and may use the channel as a water source when moving through the area. The Santa Ana River flows from the northeast and has upstream connection to large open space preserves such as Chino Hills State Park and Santiago Oaks Regional Park, approximately 8 and 5 miles northeast, respectively. The Santa Ana River channel is one of the widest and longest uninterrupted paths to these open space areas through the dense urban sprawl of Orange County, and while high-quality native habitat is scarce, it presents a viable route of movement through these areas.

The survey area also holds value for migrating birds flying through to wintering grounds that are protected by the MBTA. The survey area is within the path of the Pacific Flyway, along which millions of birds, especially waterfowl, migrate annually between Alaska and Canada, through California, to Mexico and South America. The Santa Ana River corridor and surrounding freshwater basins provide an important stopover area for a large variety of birds during their annual migration. Open water attracts shorebirds including various terns, stilts, and egrets that use waterways to forage.

4.2.2 Thresholds of Significance
According to Appendix G of the CEQA Guidelines, the project would have a significant impact on biological resources if it would:

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• Threshold BIO-1: Have a substantial adverse effect, either directly or through habitat modifications, on any species identified as a candidate, sensitive, or special status species in local or regional plans, policies, or regulations, or by the California Department of Fish and Game or U.S. Fish and Wildlife Service. • Threshold BIO-2: Have a substantial adverse effect on any riparian habitat or other sensitive natural community identified in local or regional plans, policies, regulations or by the California Department of Fish and Game or U.S. Fish and Wildlife Service. • Threshold BIO-3: Have a substantial adverse effect on state or federally protected wetlands (including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling, hydrological interruption, or other means. • Threshold BIO-4: Interfere substantially with the movement of any native resident or migratory fish or wildlife species or with established native resident or migratory wildlife corridors, or impede the use of native wildlife nursery sites. • Threshold BIO-5: Conflict with any local policies or ordinances protecting biological resources, such as a tree preservation policy or ordinance. • Threshold BIO-6: Conflict with the provisions of an adopted Habitat Conservation Plan, Natural Community Conservation Plan, or other approved local, regional, or state habitat conservation plan.

The Initial Study (Appendix A to this EIR) determined that the following thresholds would have less than significant or no impact, and these environmental topics will not be addressed further in this section of the Draft EIR.
• Threshold BIO-5
• Threshold BIO-6

4.2.3 Plans, Programs, and Policies
This section addresses plans, programs, and policies relevant to the project.

PPP BIO-1 Potential direct/indirect impacts to common and sensitive bird and raptor species will require compliance with the California Fish and Game Code Section 3503.

PPP BIO-2 The project is required to comply with the NPDES Municipal Permit and other regional permits issued by the Santa Ana RWQCB regulations through implementation of site design, source control, and incorporation of construction and permanent BMPs.

PPP BIO-3 The project is required to comply with the California Building Code and all other applicable laws, rules, and regulations governing grading as required by the Cities of Anaheim and Orange.

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PPP BIO-4 The project is required to comply with regulatory permit requirements under CWA Sections 404 and 401, Rivers and Harbors Act Section 408, and California Fish and Game Code Section 1602 administered by CDFW.

4.2.4 Environmental Impacts
Direct impacts to biological resources occur when significant alterations or destruction occurs during the course of, or because of, project implementation. Examples of such impacts include removing, disturbing, or grading vegetation; dredging or grading a stream bank; filling wetlands with any materials; erecting any structures, including in a stream; and severing or physically restricting wildlife corridors and the distribution of individual species or resources. Other direct impacts may include loss of foraging or nesting habitat and loss of individual species as a result of habitat clearing.

Indirect impacts may include elevated levels of noise or lighting, change in surface water hydrology within a floodplain, and increased erosion or sedimentation. These types of indirect impacts can affect vegetation communities or their potential use by sensitive species. They can also cause the disruption of normal wildlife functions or activities, impacting individual species.

The following sections address various potential impacts relating to biological resources that could result from implementation of the project.

4.2.4.1 Threshold BIO-1: Candidate, Sensitive, or Special-Status Species Impact Analysis
Sensitive Plant Species
Direct Impacts
No sensitive plant species were identified during the survey conducted as part of the BRTR. None of the sensitive plant species analyzed in the literature and database review were determined to have a high potential to occur in the survey area. Implementation of the project would result in impacts primarily to developed land and non-native habitats, including the concrete and ripraplined Santa Ana River channel, that do not provide suitable habitat for sensitive plant species. The native and aquatic habitats in the northern end of the project site are disturbed and have little to no potential to support sensitive plant species. Therefore, direct impacts to sensitive plant species are considered less than significant.

Indirect Impacts
No sensitive plant species were identified during the survey within the survey area, therefore, no temporary construction or long-term operational indirect impacts to sensitive plant species are anticipated. Temporary indirect impacts to sensitive plant species, if present, could result during Section 4.2: Biological Resources
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construction of the project and may include dust, which could disrupt plant vitality in the short term, or construction-related soil erosion and runoff that may permanently impact plant viability.

Permanent edge effects may include intrusions by humans and therefore possible trampling of individual plants, invasion by exotic plant and wildlife species, exposure to urban pollutants (fertilizers, pesticides, herbicides, and other hazardous materials), soil erosion, litter, and hydrologic changes (e.g., surface and groundwater level and quality). However, the project site and surrounding area already consist of disturbed habitat and urban uses subject to these edge effects. Additionally, the required compliance with the NPDES regulations through implementation of site design, source control, and incorporation of construction and permanent BMPs would ensure that indirect impacts are reduced to a less than significant level. Indirect impacts to sensitive plants during construction activities and operation of the project are less than significant.

Sensitive Wildlife Species
Direct Impacts
As described in Section 4.2.1.2, Existing Conditions, four sensitive wildlife species were observed during survey, and two additional wildlife species have a high potential to forage in the survey area:
• American white pelican (observed)
• Double-crested cormorant (observed)
• Least Bell’s vireo (observed)
• Yellow warbler (observed)
• American peregrine falcon (high potential to forage)
• Western mastiff bat (high potential to forage)
Therefore, the project has the potential to directly impact these species during construction activities through temporary displacement of individual wildlife or temporarily disrupt portions of their habitat (foraging habitat for American white pelican, double-crested cormorant, American peregrine falcon, and western mastiff bat, and suitable nesting and foraging habitat for least Bell's vireo and yellow warbler). While implementation of the project could result in temporary direct loss of habitat, including nesting and foraging habitat, for many of the sensitive wildlife species observed or with a high potential to occur in the survey area, the project proposes improvements to the Santa Ana River corridor, including aquatic and upland habitat restoration. Therefore, implementation of the project would result in a permanent increase in potentially suitable nesting and foraging habitat for sensitive wildlife species after project completion. Therefore, direct impacts to these species would be less than significant.

Temporary Direct Impacts
Potential temporary direct impacts on sensitive wildlife species observed or determined to have a high potential to occur are discussed below. Acreage estimates for temporary direct impacts on Section 4.2: Biological Resources
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sensitive wildlife species within the survey area will be determined based on site-specific assessments as project details are refined. Because the timing of construction for different components and associated precise disturbance areas are currently unknown, the Draft EIR analysis assumes a conservative estimate of disturbing the entire project site. Prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 through BIO-4 to ensure that temporary direct impacts related to wildlife species are reduced to a less than significant level. Mitigation measures include biological resources monitoring and reporting, pre-construction surveys, habitat restoration and/or compensation, and avoidance measures, ensuring impacts remain less than significant. Temporary direct impacts on these sensitive wildlife species would be mitigated to a less than significant level.

Aquatic Communities: Approximately 83.88 acres of aquatic communities, including fresh water, freshwater emergent wetland, and non-vegetated channel, occur in the survey area (refer to Table

4.2-2). Of this total, approximately 77.81 acres of aquatic communities occur on the project site and have the potential to be temporarily impacted during project implementation. These aquatic communities provide suitable foraging habitat for sensitive American white pelican and doublecrested cormorant, both observed using the Santa Ana River corridor in the northern portion of the survey area. These habitats also provide suitable foraging habitat for American peregrine falcon and western mastiff bat, both determined to have a high potential to occur in the survey area. The Santa Ana River (defined as a non-vegetated channel) provides a wide, open area above fresh water which American peregrine falcon and western mastiff bat can use as foraging habitat.

Direct temporary impacts to fresh water, freshwater emergent wetland, and non-vegetated channel could result in direct impacts to American white pelican double-crested cormorant, American peregrine falcon, and western mastiff bat in the form of temporary loss of foraging habitat. Therefore, potential temporary direct impacts to these sensitive wildlife species would be potentially significant without mitigation. However, prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 through BIO-3 to ensure that temporary direct impacts to aquatic communities are reduced to a less than significant level.

Scrub and Riparian Scrub Vegetation Communities: The 3.17 acres of scrub and riparian scrub vegetation communities, including Diegan coastal sage scrub, mule fat scrub (disturbed), and southern willow scrub. Although they are of low quality, these communities have the potential to provide some suitable nesting and foraging habitat for sensitive wildlife species. Of this total, approximately 1.25 acres of scrub and riparian scrub vegetation communities occur on the project site and have the potential to be temporarily impacted during project implementation. Least Bell’s vireo and yellow warbler were observed using the southern willow scrub in the Former Ball Road Basin in the northwestern portion of the survey area. There is potential for least Bell’s vireo and yellow warbler to use these vegetation communities in Burris Basin and the Former Ball Road Basin by moving across Ball Road, which separates the two stands of southern willow scrub. Direct Section 4.2: Biological Resources
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temporary impacts to Diegan coastal sage scrub, mule fat scrub (disturbed), and southern willow scrub could result in direct impacts to least Bell’s vireo and yellow warbler in the form of temporary loss of foraging habitat. Therefore, potential temporary direct impacts to these sensitive wildlife species would be potentially significant without mitigation. However, prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 through BIO-3 to ensure that temporary direct impacts to scrub and riparian scrub vegetation communities are reduced to a less than significant level.

Non-Native Woodland: The 0.22 acre of non-native woodland is limited to a narrow stand between The Islands Golf Center putting green and Burris Basin in the northwestern portion of the project site and does not provide high-quality nesting, roosting, or foraging habitat for the sensitive wildlife species observed or with a high potential to occur in the survey area. Therefore, potential impacts to sensitive wildlife species from removal of the non-native woodland would be less than significant, and no mitigation is required.

Developed Land: The 6.35 acres of disturbed habitat and 74.62 acres of developed land throughout the survey area provides little to no suitable habitat value for the sensitive species observed or with a high potential to occur in the survey area. However, a large number of overpasses, bridges, and buildings with crevices are present within the developed land that could provide suitable temporary roosting habitat for the western mastiff bat foraging on the project site. Potential impacts to western mastiff bat roosting habitat are discussed further under Sensitive Roosting Bats section below.

Therefore, direct temporary impacts to other sensitive wildlife species are unlikely. Potential impacts to sensitive wildlife species would be less than significant, and no mitigation is required.

Indirect Impacts
Temporary construction-related and long-term operational indirect impacts to wildlife generally include lighting, increased human activity, hydrologic quality (increased turbidity, excessive sedimentation, flow interruptions, and changes in water temperature), noise, vibration, and trash and garbage, which can attract both introduced terrestrial and native terrestrial and avian predators (such as American crows [Corvus brachyrhynchos], common ravens [Corvus corax], coyotes, domestic dogs [Canis familiaris], raccoons, and striped skunks [Mephitis mephitis]). These indirect impacts in the form of habitat disturbance and potential predation could have a significant impact on the sensitive wildlife species observed or determined to have a high potential to occur in the survey area. However, the project would be required to comply with the NPDES regulations through implementation of site design, source control, and incorporation of construction and permanent BMPs. Furthermore, the project would provide improvements to the Santa Ana River corridor, which would ultimately result in a permanent increase in potentially suitable nesting and foraging habitat for sensitive wildlife species. The project is designed to implement sustainable project elements that would transform the Santa Ana River to create a visually appealing asset and provide recreational amenities while improving the ecology of the river corridor. Therefore, Section 4.2: Biological Resources
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indirect impacts to sensitive wildlife during construction activities and operation of the project would be less than significant, and no mitigation is required.

Nesting Birds: The project site consists primarily of the concrete- and riprap-lined Santa Ana River channel, which provides limited habitat suitable for nesting birds protected under the California Fish and Game Code and MBTA. Much of the highest-quality suitable nesting habitat occurs in the northwestern portion of the survey buffer, outside the project site boundary, specifically the southern willow scrub, non-native woodland, and disturbed mule fat scrub along the fresh open water of Burris Basin, and within the emergent wetland and southern willow scrub in the Former Ball Road Basin. A large amount of avian activity was observed within the vegetation in the survey buffer, including red-winged blackbird, least Bell’s vireo, and yellow warbler, in the southern willow scrub of the Former Ball Road Basin. In addition, the ornamental trees within the non-native woodland surrounding Burris Basin in the northwestern portion of the project site may provide suitable nesting habitat for bird and raptor species. No active nests or nesting behavior were observed during the 2023 biological survey.

The project would be required to implement regulations protecting sensitive nesting birds, including the California Fish and Game Code and MBTA. Due to the known presence of federal and state endangered bird species, potential indirect impacts to these sensitive nesting birds protected under the California Fish and Game Code and MBTA are considered potentially significant without mitigation. However, prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 through BIO-4 to ensure that indirect impacts related to nesting birds are reduced to a less than significant level.

Sensitive Roosting Bats: Suitable roosting habitat for sensitive bat species, including western mastiff bat, Mexican long-tongued bat, hoary bat, big brown bat, and western red bat, occurs in the structures and ornamental trees within the developed land throughout the survey area. Although roosting bats were not observed during the biological surveys, the availability of suitable roosting with nearby foraging habitat suggests that roosting is likely occurring in the survey area. The majority of the developed land uses currently in the survey area would remain in place, and no impacts would result to the potential roosting habitat provided by the trees or structures in those areas. Any potential direct impacts to the developed land in the survey area, particularly the removal of bridges, overpasses, or ornamental trees, could result in indirect impacts to sensitive bats as permanent and temporary roosting habitat loss. Potential indirect impacts to sensitive roosting bat species during construction are considered potentially significant without mitigation.

However, prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 to ensure that temporary indirect impacts related to wildlife species, including sensitive roosting bats are reduced to a less than significant level.

Level of Significance Before Mitigation: Potentially significant.

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Mitigation Measures: Mitigation Measures BIO-1 through BIO-4 are required.

4.2.4.2 Threshold BIO-2: Riparian Habitat and Other Sensitive Natural Communities Impact Analysis
Direct Impacts
Nine vegetation communities and/or land cover types occur in the survey area (refer to Table 4.2-2) that cover 161.89 acres. Construction of the project has the potential to impact six sensitive vegetation communities that occur in the survey area, including 6.63 acres of fresh water, 0.97 acre of freshwater emergent wetland, 76.28 acres of non-vegetated channel, 1.16 acres of Diegan coastal sage scrub, 0.38 acre of mule fat scrub (disturbed), and 1.63 acres of southern willow scrub.

Acreage estimates for temporary direct impacts on sensitive vegetation communities within the survey area will be determined as project details are refined. Because the timing of construction for different components and associated precise disturbance areas are currently unknown, the Draft EIR analysis assumes a conservative estimate of disturbing the entire project site. Prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO1 through BIO-3 to ensure that temporary direct impacts related to sensitive vegetation communities are reduced to a less than significant level. Mitigation measures include biological resources monitoring and reporting, pre-construction surveys, habitat restoration and/or compensation, and avoidance measures, ensuring impacts remain less than significant with mitigation incorporated.

Indirect Impacts
Most indirect impacts to sensitive plant species described in Section 4.2.4.1 would also result in potentially significant indirect impacts to sensitive vegetation communities. As previously discussed in Section 4.2.4.1, the project is required to comply with the NPDES regulations through implementation of site design, source control, and incorporation of construction and permanent BMPs. The project is designed to implement sustainable project elements that would transform the Santa Ana River to create a visually appealing asset and provide recreational amenities while improving the ecology of the river corridor. Therefore, indirect impacts to sensitive vegetation communities during construction activities and project operation would be less than significant, and no mitigation is required.

Level of Significance Before Mitigation: Potentially significant.

Mitigation Measures: Mitigation Measures BIO-1 through BIO-3 are required.

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4.2.4.3 Threshold BIO-3: Jurisdictional Aquatic Resources Impact Analysis
Direct Impacts
As discussed in Section 4.2.1.2, a total of 85.51 acres of non-wetland waters, freshwater emergent wetland, and riparian potentially under the jurisdiction of the USACE, RWQCB, and CDFW occur in the survey area. These potentially jurisdictional aquatic resources in the survey area include approximately 82.91 acres of non-wetland waters (Santa Ana River, Collin’s Channel, Burris Basin, and the Former Ball Road Basin), 0.97 acre of wetland (emergent wetland in the former Ball Road Basin), and 1.63 acre of riparian (southern willow scrub in Burris Basin). As discussed in Section 4.2.4.1 (Threshold BIO-1) under Sensitive Vegetation Communities, the project would result in direct impacts to the aquatic and riparian vegetation communities potentially under the jurisdiction of the USACE, RWQCB, and CDFW. Further, the reach of the Santa Ana River in the survey area contains the SAR1 Levee System (Upstream Reach) and, therefore, is under the jurisdiction of the USACE pursuant to the Rivers and Harbors Act, Section 408.

Acreage estimates for temporary direct impacts to the aquatic and riparian vegetation communities within the survey area will be determined based on site-specific assessments as project details are refined. Because the timing of construction for different components and associated precise disturbance areas are currently unknown, the Draft EIR analysis assumes a conservative estimate of disturbing the entire project site. Prior to start of construction activities, the City of Anaheim will be required to implement Mitigation Measures BIO-1 through BIO-3 to ensure that temporary direct impacts related to jurisdictional aquatic resources are reduced to a less than significant level.

Mitigation measures include biological resources monitoring and reporting, pre-construction surveys, habitat restoration and/or compensation, and avoidance measures, ensuring impacts remain less than significant.

As previously discussed in Section 4.2.1.1, Regulatory Setting, and in Section 2.5.1, Other Agency Approvals, the project is required to comply with federal, state, and local regulations protecting biological resources. This includes complying with applicable federal and state regulations that ensure no net loss of aquatic resources, such as Sections 404 and 401 of the federal CWA, Section 408 of the Rivers and Harbors Act, Section 1602 of the California Fish and Game Code, and PorterCologne Act. The project is required to obtain appropriate regulatory permits from the USACE, RWQCB, and CDFW and provide compensatory mitigation for impacts prior to the start of construction that would ensure that no net loss of resources would result from implementation of the project. Therefore, direct impacts to jurisdictional aquatic resources would be less than significant with mitigation incorporated.

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Indirect Impacts
Most of the indirect impacts to sensitive plant species and sensitive vegetation communities described in Section 4.2.4.1 would also result in potentially significant indirect impacts to jurisdictional aquatic resources. As previously discussed in Section 4.2.4.1, the project would be required to comply with the NPDES regulations, through implementation of site design, source control, and incorporation of construction and permanent BMPs. The project is designed to implement sustainable project elements that would transform the Santa Ana River to create a visually appealing asset and provide recreational amenities while improving the ecology of the river corridor. Therefore, indirect impacts to jurisdictional aquatic resources during construction activities and project operation would be less than significant, and no mitigation is required.

Level of Significance Before Mitigation: Potentially significant.

Mitigation Measures: Mitigation Measures BIO-1 through BIO-3 are required.

4.2.4.4 Threshold BIO-4: Wildlife Corridors and Habitat Linkages Impact Analysis
Direct Impacts
As discussed in Section 4.2.1.2, the survey area is likely used as a wildlife movement corridor and provides suitable nesting, foraging, and dispersal areas primarily for highly mobile species like bats and birds, and some movement opportunities for mammals. The dense urban development surrounding the survey area restricts movement opportunities for many small and large mammals, amphibians, and reptiles. However, mesocarnivores and medium-size mammals, such as raccoons, coyotes, or bobcats, could use the access roads that border the Santa Ana River channel for movement and may use the channel as a water source when moving through the area. The Santa Ana River channel, the widest and longest uninterrupted path through the dense urban sprawl of Orange County connecting to open space areas to the north, presents a viable route of wildlife movement through the survey area. The survey area also holds value for migrating birds, protected by the MBTA, flying within the Pacific Flyway to their wintering grounds.

Project impacts are proposed primarily in areas adjacent to and within existing development and would only be temporary impacts that occur during construction activities in the survey area. Existing wildlife corridors would remain in place, and their quality would increase after implementation of the project.

Therefore, significant direct long-term impacts to wildlife corridors and habitat connectivity provided by the survey area are not expected to occur. While project activities may temporarily disrupt wildlife movement through the survey area, the project is not expected to have a significant impact on habitat linkage over the long term because the overall habitat quality of the existing corridors would be maintained and improved following project implementation. Therefore, impacts to wildlife corridors and habitat connectivity would be less than significant.

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Indirect Impacts
Wildlife movement corridors and habitat connectivity would be impacted by many of the other indirect effects discussed in Section 4.2.4.1, for impacts to sensitive wildlife species. As previously discussed in that section, the project is required to comply with the NPDES regulations through implementation of site design, source control, and incorporation of construction and permanent BMPs. The project is designed to implement sustainable project elements that would transform the Santa Ana River to create a visually appealing asset and provide recreational amenities while improving the ecology of the river corridor. Therefore, indirect impacts to wildlife movement corridors and habitat connectivity during construction activities and operation of the project would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.2.5 Cumulative Impacts
This section addresses various potential cumulative impacts relating to biological resources that could result from implementation of the project.

4.2.5.1 Cumulative Threshold BIO-1: Candidate, Sensitive, or Special-Status Species
Nearby surrounding areas with similar biological resources defined the cumulative survey area specific to biological resources. Cumulative projects in the vicinity of the survey area would have the potential to result in impacts to sensitive plant and wildlife species, including loss of habitat.

Cumulative projects that are proposed in the cities of Anaheim and Orange would impact primarily developed land covers but could potentially include portions of undeveloped open space.

Implementation of these cumulative projects have the potential to result in impacts to sensitive plant and wildlife species. However, as with the project, all other cumulative projects are required to comply with CEQA, including limiting impacts to biological resources. Through implementation of Mitigation Measures BIO-1 through BIO-4, the project would reduce temporary and permanent impacts to sensitive plant and wildlife species to less than significant and would therefore not contribute to cumulative impacts. Once the project is completed, the project would improve the river and riverbed’s groundwater recharge potential and improve the river corridor’s ecology (flora and fauna), resulting in net benefit pertaining to biological resources. Therefore, cumulative impacts to sensitive plant and wildlife species would be less than significant with mitigation incorporated.

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4.2.5.2 Cumulative Threshold BIO-2: Riparian Habitat and Other Sensitive Natural Communities
As discussed in Section 4.2.5.2, the project’s implementation of Mitigation Measures BIO-1 through BIO-3 would ensure that the project, in combination with other cumulative projects in the cities of Anaheim and Orange, would not result in cumulatively considerable impacts to biological resources, specifically sensitive vegetation communities. In fact, the project would provide a net benefit to the vegetation communities in the survey area by protecting and restoring the functions of the Santa Ana River aquatic and adjacent habitats. Therefore, because the project minimizes impacts to sensitive vegetation communities, it would not result in a cumulatively considerable impact to sensitive vegetation communities.

4.2.5.3 Cumulative Threshold BIO-3: Jurisdictional Aquatic Resources As discussed in Section 4.2.5.2, the project’s implementation of Mitigation Measures BIO-1 through BIO-3 would ensure that the project, in combination with other cumulative projects in the cities of Anaheim and Orange, would not result in cumulatively considerable impacts to biological resources, specifically jurisdictional aquatic resources. In fact, the project would provide a net benefit to the vegetation communities in the survey area by protecting and restoring the functions of the Santa Ana River aquatic and adjacent habitats. Therefore, because the project minimizes impacts to jurisdictional aquatic resources, it would not result in a cumulatively considerable impact to jurisdictional aquatic resources. In addition, cumulative projects with potential impacts to jurisdictional aquatic resources would be required to comply with applicable federal and/or state regulations that ensure no net loss of resources, such as Section 404 of the federal CWA; Sections 9, 10, and 408 of the Rivers and Harbors Act; Section 1602 of the California Fish and Game Code; and the Porter-Cologne Act. Therefore, because the project would minimize impacts to jurisdictional aquatic resources and would comply with federal and state permitting regulations, the project would not result in a cumulatively considerable impact to jurisdictional aquatic resources.

4.2.5.4 Cumulative Threshold BIO-4: Wildlife Corridors and Habitat Linkages As discussed in Section 4.2.4.4, the project is not expected to significantly impact wildlife corridors and habitat linkages over the long term because the overall habitat quality of the existing corridors would be maintained following project implementation. Therefore, the project would not result in a cumulatively considerable impact to wildlife corridors and habitat linkages.

4.2.6 Level of Significance Before Mitigation
Upon implementation of the plans, programs, and policies, the following threshold would be less than significant.
• Threshold BIO-4: Implementation of the project would not adversely impact wildlife corridors and habitat linkages.

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Without mitigation, the following thresholds would be potentially significant:
• Threshold BIO-1: Implementation of the project could adversely impact special status wildlife species.
• Threshold BIO-2: Implementation of the project could adversely impact sensitive vegetation communities.
• Threshold BIO-3: Implementation of the project could adversely impact state or federally protected wetlands.

4.2.7 Mitigation Measures

4.2.7.1 Threshold BIO-1: Candidate, Sensitive, or Special-Status Species BIO-1: Qualified Monitoring Biologist. Before the start of construction activities, the City of Anaheim project manager (or designee) shall retain a qualified monitoring biologist to implement required monitoring and document the names and resumes of the people involved in the biological monitoring of the project and a schedule for the proposed work.

The qualified monitoring biologist shall be responsible for the following monitoring and reporting tasks:
• Biological Construction Mitigation/Monitoring Exhibit. Before the start of construction within the future site-specific proposed survey area, the qualified monitoring biologist shall submit a Biological Construction Mitigation/Monitoring Exhibit, which includes limits of work, proposed monitoring schedule, bird, focused sensitive species, or other wildlife surveys/survey schedules (including general avian nesting and U.S. Fish and Wildlife Service protocol), timing of surveys, bird construction avoidance areas/noise buffers/barriers, other impact avoidance areas, and any subsequent requirements determined by the qualified monitoring biologist. The Biological Construction Mitigation/Monitoring Exhibit shall include the construction site plan, written and graphic depiction of the project’s biological mitigation/monitoring program, and a schedule for construction activities. Where the potential for impacts to biological resources is limited (e.g., construction within a footprint that consists entirely of previously developed or disturbed lands), the Biological Construction Mitigation/Monitoring Exhibit may be limited to a pre- and post-maintenance verification inspection. For highly sensitive resource areas, full-time biological monitors may be required. The Biological Construction Mitigation/Monitoring Exhibit shall be approved by the City of Anaheim project manager (or designee) before the start of construction. • Avian Protection. To avoid any direct impacts to raptors and/or any migratory birds protected under the Migratory Bird Treaty Act, removal of habitat that supports active nests on the proposed area of disturbance should occur outside the breeding Section 4.2: Biological Resources
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season for these species (January 15 to August 31). If removal of habitat on the proposed area of disturbance must occur during the breeding season, the monitoring biologist shall conduct a pre-construction survey to determine the presence or absence of nesting birds on the proposed area of disturbance. The pre-construction survey must be conducted within 10 calendar days before the start of construction, the results of which must be submitted to the City of Anaheim project manager (or designee) for review and approval before initiating any construction activities. If nesting birds are detected, a letter report or mitigation plan as deemed appropriate by the City of Anaheim shall be prepared and include proposed measures to be implemented to ensure that disturbance of raptor and bird breeding activities are avoided. The report or mitigation plan shall be submitted to the City of Anaheim for review and approval and implemented to the satisfaction of the City of Anaheim. The monitoring biologist shall verify and approve that all measures identified in the report or mitigation plan are in place prior to and/or during construction. • Resource Marking/Protection. Prior to the start of construction activities within the future site-specific proposed survey area, the qualified monitoring biologist shall supervise the placement of orange construction fencing or similar visible marker, staking, or flagging along the limits of the construction area, particularly where adjacent to sensitive biological avoidance areas, as shown on the Biological Construction Mitigation/Monitoring Exhibit to ensure crews remain within the approved construction limits. These demarcations shall not be required for areas with existing barriers, such as chain-link fencing, along the limits or facilities that are within and/or adjacent to developed and non-sensitive habitat areas. This task shall include flagging plant specimens and delineating buffers to protect sensitive biological resources (e.g., habitats, sensitive plant and wildlife species, including nesting birds) prior to construction.
• Cover Trenches. The qualified monitoring biologist shall oversee the construction site so that cover and/or escape routes for wildlife from excavated areas shall be provided daily. Steep trenches, holes, and excavations during construction shall be covered at night with backfill, plywood, metal plates, or other means, and if plastic sheeting is used, the edges must be covered with soils such that small wildlife cannot access the excavated hole. Soil piles shall be covered at night to prevent wildlife from burrowing in. Sandbags shall weigh down the edges of the sheeting. These areas may also be fenced to prevent wildlife from gaining access. Exposed trenches, holes, and excavations shall be inspected twice daily (i.e., each morning and before sealing the exposed area) by the qualified monitoring biologist to monitor for wildlife entrapment. Excavations shall provide an earthen ramp to allow for a wildlife escape route. The qualified monitoring biologist shall verify that the contractor has covered all steep-walled trenches or excavations prior to the end of construction daily. If Section 4.2: Biological Resources
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wildlife species are encountered within any trenches or excavated areas, the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape (e.g., a ramp or sloped surface at no greater than a 30-degree angle) and allow the species to disperse. In addition, the qualified monitoring biologist shall train construction personnel to increase awareness of the possible presence of wildlife beneath vehicles and equipment and to use best judgment to avoid killing or injuring wildlife (refer to Pre-Construction Meeting/Education). • Structure Clearance. Before the issuance of any permit to allow for the removal or demolition of trees on the project site (particularly any ornamental trees in the developed land areas), the qualified monitoring biologist shall conduct clearance surveys to flush out any wildlife species nesting, roosting, or otherwise occupying the trees. If wildlife species are encountered within any of the trees (outside the general bird nesting season), the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape and allow the species to disperse. If tree-roosting bats are suspected, slow removal by gently pushing the tree over with heavy equipment is required.
• Pre-Construction Meeting/Education. Before the start of any construction activity where the site plan for the construction area indicates that significant impacts to biological resources may occur, a pre-construction meeting shall be held on site with the following in attendance: City of Anaheim project manager (or designee), the construction contractor (if applicable), and the qualified monitoring biologist.

At this meeting, the qualified monitoring biologist shall identify and discuss the construction protocols that apply to the proposed activities and the sensitive nature of the adjacent habitat with appropriate project personnel.

Before the start of construction activities, the qualified monitoring biologist shall meet with the construction contractor and crew and conduct an on-site educational session regarding the need to avoid impacts outside the approved construction footprint and to protect sensitive plants and wildlife that may occur at the specific facility. This may include but not be limited to explanations of the avian and aquatic resource buffers, the flag system for retention of sensitive plants, and clarification of acceptable access routes/methods and staging areas.
• Biological Monitoring and Reporting. The qualified monitoring biologist shall inspect/monitor the project construction area in accordance with the approved Biological Construction Mitigation/Monitoring Exhibit. This may be limited to pre- Section 4.2: Biological Resources
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and post-maintenance inspections, weekly visits, or full-time monitoring, as determined by the qualified monitoring biologist.

If no deviations from the construction site plan occur during maintenance, no additional documentation is required. However, if deviations from the site plan do occur, such as unanticipated impacts to sensitive vegetation communities or unanticipated discharge of pollutants, a Final Monitoring Report shall be prepared within 3 months following the completion of mitigation monitoring detailing maintenance and monitoring that occurred and any remedial or compensatory measures taken.

Army Corps of Engineers
• Potential direct impacts to sensitive vegetation communities, including jurisdictional aquatic resources, resulting from project implementation shall be mitigated through one of the following two options:
− Project compensatory mitigation for proposed impacts to sensitive vegetation communities, including jurisdictional aquatic resources, shall be provided through in-kind and on-site creation, enhancement, and/or restoration. A Habitat Mitigation and Monitoring Plan shall be provided and prepared in accordance with the City of Anaheim and regulatory agency requirements.

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− Compensatory mitigation requirements that are not able to be satisfied through on-site creation, enhancement, and/or restoration shall be satisfied through the acquisition of mitigation bank credits via a resource agency-approved mitigation site within the Santa Ana River Watershed or by acquisition of other approved off-site mitigation credits. Prior to implementation of project construction impacts that would require compensatory mitigation, documentation demonstrating the availability of mitigation credits (i.e., credit ledger) at the approved mitigation site must be submitted to the City of Anaheim project manager (or designee) for confirmation.

For mitigation that involves habitat acquisition, the Habitat Mitigation and Monitoring Plan shall include the following:
• Location of proposed acquisition.
• Description of the biological resources to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss.
• Documentation that the mitigation area would be adequately preserved and maintained in perpetuity.

The identification of mitigation site credits shall be provided to the City of Anaheim project manager (or designee) and shall include the following:
• Location of approved mitigation site.
• Description of the mitigation credits to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss.
• Documentation of the credits that are associated with a mitigation bank, which has been approved by the appropriate resource agencies. • Documentation in the form of a current mitigation credit ledger.

BIO-3: Habitat Restoration in Temporary Impact Areas. Temporary direct impact areas shall be restored to pre-construction topographic contours and conditions, including the Section 4.2: Biological Resources
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revegetation of native plant communities, where appropriate. Habitat restoration and erosion control treatments shall be installed within these short-term impact areas. Habitat revegetation shall feature native species that are typical of the area, and associated erosion control best management practices shall include silt fence and microplastic- and weed-free straw fiber rolls, where appropriate. The revegetation areas shall be monitored and maintained for 25 months to ensure adequate establishment and sustainability of the plantings/seedings.

BIO-4: Least Bell’s Vireo and Yellow Warbler Pre-Construction Surveys. For any work proposed in or near suitable habitat between February 15 and August 15 (March 15 and September 15 for least Bell’s vireo), a pre-construction survey for least Bell’s vireo and yellow warbler shall be performed to reaffirm the presence and extent of occupied habitat. The survey shall occur within five days prior to the start of construction. The pre-construction survey area for the species shall encompass all potentially suitable habitat within the project work zone and a 300- foot survey buffer. The pre-construction survey shall be performed to the satisfaction of the City of Anaheim project manager (or their designee) by a qualified biologist familiar with the species. The results of the pre-construction survey shall be submitted in a report to the City of Anaheim project manager (or their designee) for review and approval before initiating any construction activities. If least Bell’s vireo or yellow warbler are detected, a minimum 300- foot buffer delineated by orange biological fencing shall be established around the detected species. In addition, on-site noise reduction/attenuation techniques shall be incorporated, as appropriate, to avoid impacts to breeding least Bell’s vireo and yellow warbler from elevated construction noise levels during the breeding season. The City of Anaheim project manager (or their designee) shall have the discretion to modify the buffer width depending on site-specific conditions. In addition, noise monitoring may be required to ensure that the elevated construction noise levels are appropriately attenuated at the edge of occupied habitat to a level that is not expected to adversely affect nesting bird Section 4.2: Biological Resources
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behavior (i.e., not to exceed an hourly average of 60 A-weighted decibels or ambient whichever is greater, at the edge of occupied habitat).

4.2.7.2 Threshold BIO-2: Riparian Habitat and Other Sensitive Natural Communities
Refer to Mitigation Measure BIO-1 through Mitigation Measure BIO-3.

4.2.7.3 Threshold BIO-3: Jurisdictional Aquatic Resources Refer to Mitigation Measure BIO-1 through Mitigation Measure BIO-3.

4.2.8 Level of Significance After Mitigation

4.2.8.1 Threshold BIO-1: Candidate, Sensitive, or Special-Status Species Implementation of Mitigation Measure BIO-1 through Mitigation Measure BIO-4 would mitigate potential direct impacts to sensitive wildlife species and their habitats to below a level of significance through monitoring by a qualified biologist, providing mitigation ratios for acreage impacts, the creation and restoration of impacted vegetation communities, and preconstruction sensitive nesting bird surveys.

Implementation of Mitigation Measure BIO-1 would mitigate potential direct impacts to sensitive nesting birds and roosting bats to below a level of significance. This mitigation measure would require monitoring by a qualified biologist responsible for conducting pre-construction nesting bird surveys and identifying and flushing any roosting bats from trees before construction. No significant and unavoidable impacts would remain.

4.2.8.2 Threshold BIO-2: Riparian Habitat and Other Sensitive Natural Communities
Implementation of Mitigation Measure BIO-1 through Mitigation Measure BIO-3 would reduce potential direct impacts to sensitive vegetation communities to below a level of significance through monitoring by a qualified biologist, adhering to required mitigation ratios for acreage impacts, and creating new vegetation communities and restoring impacted ones. No significant and unavoidable impacts would remain.

4.2.8.3 Threshold BIO-3: Jurisdictional Aquatic Resources Implementation of Mitigation Measure BIO-1 through Mitigation Measure BIO-3 would mitigate potential direct impacts to jurisdictional aquatic resources to below a level of significance through monitoring by a qualified biologist, adhering to required mitigation ratios for acreage impacts, and restoring temporary impact areas. No significant and unavoidable impacts would remain.

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Section 4.3: Cultural Resources
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4.3 Cultural Resources
This section evaluates the potential for impacts relating to cultural resources resulting from implementation of the OC River Walk Project (project).

The analysis in this section is based in part on the OC River Walk Project Cultural Resources Survey Letter Report – Negative Findings prepared by Harris & Associates (2024). A complete copy of the report is included in Appendix E, Cultural Memo.

4.3.1 Environmental Setting

4.3.1.1 Regulatory Setting
The treatment of cultural resources is governed by federal and state laws and guidelines. Specific criteria exist to determine if prehistoric and historic sites or objects are significant or protected by law. Federal and state significance criteria generally focus on the resource’s integrity and uniqueness, its relationship to similar resources, and its potential to contribute important information to scholarly research. Some resources that do not meet federal significance criteria may be considered significant under state criteria. The laws and regulations seek to mitigate impacts to significant prehistoric or historical resources. The federal and state laws and guidelines for protecting historical resources are summarized below.

Federal
National Historic Preservation Act (U.S. Code, Title 54, Section 300101 et seq.) The National Historic Preservation Act of 1966 established the National Register of Historic Places (NRHP) as the official federal list of cultural resources that have been nominated by state offices for their historical significance at the local, state, or national level. Listing in the NRHP provides recognition that a property is significant to the nation, the state, or the community and assumes that federal agencies consider historical value in the planning for federal and federally assisted projects.

Properties listed in the NRHP or determined eligible for listing must meet certain criteria for historical significance and possess integrity of form, location, and setting. Structures and features must usually be at least 50 years old to be considered for listing in the NRHP, barring exceptional circumstances.

Criteria for listing in the NRHP, which are set forth in the Code of Federal Regulations, Title 36, Part

60.4, are as follows: the quality of significance in American history, architecture, archaeology, engineering, and culture is present in districts, sites, buildings, structures, and objects that possess integrity of location, design, setting, materials, workmanship, feeling, and association and that:

A. Are associated with events that have made a significant contribution to the broad patterns of our history; or
B. Are associated with the lives of persons significant in our past; or Section 4.3: Cultural Resources
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C. Embody the distinctive characteristics of a type, period, or method of construction; represent the work of a master; possess high artistic values; represent a significant and distinguishable entity whose components may lack individual distinction; or D. Have yielded, or may be likely to yield, information important in prehistory or history.

Eligible properties must meet at least one of the criteria and exhibit integrity, which is measured by the degree to which the resource retains its historic properties and conveys its historic character, the degree to which the original fabric has been retained, and the reversibility of changes to the property. The fourth criterion is typically reserved for archaeological and paleontological resources. These criteria have largely been incorporated into the California Environmental Quality Act (CEQA) Guidelines.

Native American Graves Protection and Repatriation Act (U.S. Code, Title 25, Section 3001 et seq.)
The Native American Graves Protection and Repatriation Act (NAGPRA) of 1990 provides a process for museums and federal agencies to return certain Native American cultural items— human remains, funerary objects, sacred objects, or objects of cultural patrimony—to lineal descendants and culturally affiliated Native American Tribes and Native Hawaiian organizations.

NAGPRA includes provisions for unclaimed and culturally unidentifiable Native American cultural items, intentional and inadvertent discovery of Native American cultural items on federal and Tribal lands, and penalties for noncompliance and illegal trafficking. Implementation of the project would be conducted in compliance with NAGPRA.

Federal curation regulations are also provided in the Code of Federal Regulations, Title 36, Part 79, and apply to collections that are excavated or removed under the authority of the Antiquities Act (16 USC 431–433), the Reservoir Salvage Act (16 USC 469–469c), Section 110 of the National Historic Preservation Act (16 USC 470h-2), or the Archaeological Resources Protection Act (16 USC 470aa–mm). Such collections generally include those that are the result of a prehistoric or historical resources survey, excavation, or other study conducted in connection with a federal action, assistance, license, or permit.

State
Assembly Bill 52: Native Americans: California Environmental Quality Act Assembly Bill (AB) 52 (Chapter 532, Statutes of 2014) establishes a formal consultation process for California Native American Tribes as part of CEQA and equates significant impacts on Tribal Cultural Resources (TCRs) with significant environmental impacts (California Public Resources Code, Section 21084.2). California Public Resources Code, Section 21074, defines TCRs as follows:

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1. Sites, features, places, cultural landscapes, sacred places, and objects with cultural value to a California Native American tribe that are either of the following:
a. Included or determined to be eligible for inclusion in the California Register of Historical Resources.
b. Included in a local register of historical resources as defined in subdivision (k) of Section 5020.1.

2. A resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to criteria set forth in subdivision (c) of Section 5024.1.

Sacred places can include Native American sanctified cemeteries, places of worship, religious or ceremonial sites, and sacred shrines. In addition, both unique and non-unique archaeological resources, as defined in California Public Resources Code, Section 21083.2, can be TCRs if they meet the criteria detailed above. The lead agency relies on substantial evidence to make the determination that a resource qualifies as a TCR when it is not already listed in the California Register of Historical Resources (CRHR) or a local register.

AB 52 defines a “California Native American Tribe” as a Native American Tribe in California that is on the contact list maintained by the Native American Heritage Commission (NAHC) (California Public Resources Code, Section 21073). Under AB 52, formal consultation with Tribes is required before determining the level of environmental document if a Tribe has requested to be informed by the lead agency of proposed projects and if the Tribe, upon receiving notice of the project, accepts the opportunity to consult within 30 days of receipt of the notice. AB 52 also requires that consultation, if initiated, address project alternatives and mitigation measures for significant effects if specifically requested by the Tribe. AB 52 states that consultation is considered concluded when the parties agree to measures to mitigate or avoid a significant effect on TCRs or when either the Tribe or the lead agency concludes that mutual agreement cannot be reached after making a reasonable, good-faith effort. Under AB 52, any mitigation measures recommended by the lead agency or agreed on with the Tribe may be included in the final environmental document and in the adopted Mitigation Monitoring and Reporting Program if the mitigation measures were determined to avoid or lessen a significant impact on a TCR.

If the recommended measures are not included in the final environmental document, then the lead agency must consider the four mitigation methods described in California Public Resources Code, Section 21084.3(e). Any information submitted by a Tribe during the consultation process is considered confidential and is not subject to public review or disclosure. It will be published in a confidential appendix to the environmental document unless the Tribe consents to disclosure of all or some of the information to the public.

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Assembly Bill 978: California Native American Graves Protection and Repatriation Act The California NAGPRA, enacted in 2001, required the state agencies and museums that receive state funding and that have possession or control over collections of human remains or cultural items, as defined, to complete an inventory and summary of these remains and items on or before January 1, 2003, with certain exceptions. California NAGPRA also provides a process for the identification and repatriation of these items to the appropriate Tribes.

California Government Code, Sections 6254(r) and 6254.10 Sections 6254(r) and 6254.10 of the California Government Code were enacted to protect archaeological sites from unauthorized excavation, looting, or vandalism. Section 6254(r) explicitly authorizes public agencies to withhold information from the public relating to “Native American graves, cemeteries, and sacred places maintained by the Native American Heritage Commission.” Section 6254.10 specifically exempts from disclosure requests for “records that relate to archaeological site information and reports, maintained by, or in the possession of the Department of Parks and Recreation, the State Historical Resources Commission, the State Lands Commission, the NAHC, another state agency, or a local agency, including the records that the agency obtains through a consultation process between a Native American tribe and a state or local agency.” California Health and Safety Code, Section 7050.5, and California Public Resources Code, Section 5097.9
California Health and Safety Code, Section 7050.5, addresses the protection of human remains discovered in any location other than a dedicated cemetery and makes it a misdemeanor for any person who knowingly mutilates or disinters, wantonly disturbs, or willfully removes any human remains in or from any location other than a dedicated cemetery without authority of law, except as provided in California Public Resources Code, Section 5097.99. It further states that, in the event of discovery or recognition of any human remains in any location other than a dedicated cemetery, no further excavation or disturbance of the site or any nearby area reasonably suspected to overlie adjacent remains will occur until the coroner of the county in which the human remains are discovered has determined that the remains are not subject to the provisions concerning investigation of the circumstances, manner, and cause of any death and that the recommendations concerning the treatment and disposition of the human remains have been made to the person responsible for the excavation, or to their authorized representative, in the manner provided in California Public Resources Code, Section 5097.98. If the county coroner determines that the remains are not subject to their authority and if the county coroner recognizes the human remains to be those of a Native American or has reason to believe that they are those of a Native American, they shall contact, within 24 hours by telephone, the NAHC. Whenever the NAHC receives notification of a discovery of Native American human remains from the county coroner, the agency shall immediately notify the most likely decadent if it believes them to be the most likely Section 4.3: Cultural Resources
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descendant of the deceased Native American. The most likely descendant may inspect the site of the discovery and make recommendations on the removal or reburial of the remains.

California Register of Historical Resources
The CRHR is a state government program for use by state and local agencies, private groups, and citizens to identify, evaluate, register, and protect California’s historical resources. The CRHR is the authoritative guide to the state’s significant historical and archaeological resources and encourages public recognition and protection of resources of architectural, historical, archaeological, and cultural significance; identifies historical resources for state and local planning purposes; determines eligibility for state historic preservation grant funding; and affords certain protections under CEQA.

The term “historical resource” includes but is not limited to any object, building, structure, site, area, place, record, or manuscript that is historically or archaeologically significant or is significant in the architectural, engineering, scientific, economic, agricultural, educational, social, political, military, or cultural annals of California (California Public Resources Code, Section 5020.1[j]).

Historical resources may be designated as such through three different processes:
• Official designation or recognition by a local government pursuant to local ordinance or resolution (California Public Resources Code, Section 5020.1[k]) • A local survey conducted pursuant to California Public Resources Code, Section 5024.1(g) • Listing in or eligibility for listing in the NRHP (California Public Resources Code, Section 5024.1[d][1])
To be eligible for listing in the CRHR, a building must satisfy at least one of the following four criteria:
• Criterion 1. It is associated with events that have made a significant contribution to the broad patterns of local or regional history or the cultural heritage of California or the United States.
• Criterion 2. It is associated with the lives of persons important to local, California, or national history.
• Criterion 3. It embodies the distinctive characteristics of a type, period, region, or method of construction or represents the work of a master or possesses high artistic values. • Criterion 4. It has yielded, or has the potential to yield, information important to the prehistory or history of the local area, California, or the nation.

Native American Historic Cultural Sites (California Public Resources Code, Section 5097 et. seq.)
State law addresses the disposition of Native American burials in archaeological sites and protects such remains from disturbance, vandalism, or inadvertent destruction; establishes procedures to be implemented if Native American skeletal remains are discovered during construction of a project; Section 4.3: Cultural Resources
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and establishes the NAHC to resolve disputes regarding the disposition of such remains. In addition, the Native American Historic Resource Protection Act makes it a misdemeanor punishable by up to 1 year in jail to deface or destroy a Native American historical or cultural site that is listed or may be eligible for listing in the CRHR.

Senate Bill 18: Traditional Tribal Cultural Places
As of March 1, 2005, Senate Bill (SB) 18 (California Government Code, Sections 65352.3 and 65352.4) requires that, before the adoption or amendment of a General Plan proposed on or after March 1, 2005, a city or county must consult with Native American Tribes with respect to the possible preservation of, or the mitigation of impacts to, specified Native American places, features, and objects within that jurisdiction. The consultation intends to establish a meaningful dialogue regarding potential means to preserve Native American places of importance. It allows for Tribes to hold conservation easements and for Tribal Cultural Places to be included in open space planning.

Local
City of Anaheim General Plan
The General Plan includes the following goals and policies related to historical resources that are specific to residential areas of the Anaheim Colony. However, those goals and policies do not apply to this project. No goals or policies are included in the General Plan related to archaeological resources or human remains.

City of Anaheim Citywide Historic Preservation Plan
In May 2010, the Anaheim City Council approved the Citywide Historic Preservation Plan, a list of contributors in the local historic districts, and a complete list of citywide historic structures.

This plan provides procedures and criteria for designating historical resources. The Preservation Plan provides criteria for selecting special properties that merit historic designation. Official designation does not occur until the Planning and Building Director or the City Council certifies at the end of the application process that a building, structure, object, or district meets the criteria for designation. The City of Anaheim has three levels of recognition: (1) Historic Districts; (2) Historically Significant Structures; and (3) List of Structures of Historical Interest. “Historic Districts” are usually contiguous groups of buildings that are best evaluated together due to their common history and physical characteristics that contribute to the significance of the district. “Historic Districts” are usually contiguous groups of buildings that are best evaluated together due to their common history and physical characteristics that contribute to the significance of the district. “Historically Significant Structures” are single properties outside historic districts that are visually identifiable reminders of the City’s history and the development of its built environment.

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The City maintains a “List of Structures of Historical Interest” to track properties outside existing districts that have been identified by City staff or the public. These properties are simply a part of the City’s record for planning purposes. With further research, many of the properties on the list may be considered eventually for the higher designation of Historically Significant Structure.

The plan supplements the 1999 Anaheim Colony Historic District Preservation Plan and applies to the four historic districts (Anaheim Colony, Five Points, Historic Palm, and Hoskins) within the City. The plan does not apply to this project.

City of Anaheim Colony Historic District Preservation Plan The Anaheim Colony Historic District Preservation Plan (Preservation Plan) (City of Anaheim 1999) provides basic guidelines and encourages property owners to take special care in preserving, protecting, or enhancing historic buildings. This plan does not apply to this project.

City of Anaheim Preservation Program
When the owner of a designated historic property or a potentially historic property (i.e., one included on the Structures of Historical Interest list) applies to the Building Division for a building permit, the property is flagged for consultation with historic preservation program staff.

All buildings identified as contributors to historic districts, Qualified Historic Structures in districts, Historically Significant Structures, and buildings on the citywide Structures of Historical Interest list that have been surveyed using a California Department of Parks and Recreation Form 523a require review prior to issuance of a demolition permit by the City’s Building Division. This process is not intended to apply to demolitions ordered by the Building Division Official or Fire Chief of the City of Anaheim to remedy conditions determined to be dangerous to life, health, safety, or property.

City of Orange General Plan
The General Plan includes goals and policies related to Cultural Resources and Historic Preservation. The Cultural Resources and Historic Preservation Element (Element) is based on prior actions taken to recognize historical resources and is an effort to expand the City’s historic preservation program to ensure recognition and preservation of the City’s resources. The Element provides guidelines to preserve those resources that represent the history and culture of Orange.

Specifically, its purpose is to provide guidance in developing and implementing programs that ensure the identification, designation, and protection of cultural resources in the City’s planning, development, and permitting process. The Element also identifies ways in which the City can encourage and coordinate with private property owners in support of historic preservation. The following goals and policies are identified in the Element:

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• Goal 1.0 – Architecture and Community Resources: Identify and preserve potential and listed historic resources, including buildings, structures, objects, sites, districts, and archaeological resources citywide.
− Policy 1.1: Maintain an accessible inventory of designated and potential historic resources.
− Policy 1.2: Promote community education and awareness of the significance of Orange’s potential and listed historic resources.
− Policy 1.3: Provide long term assurance that potential and listed historic resources will be used, maintained, and rehabilitated in conformance with Secretary of the Interior’s Standards for the Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring and Preserving Historic Buildings (Secretary’s Standards).
− Policy 1.4: Encourage alternatives to demolition such as architecturallycompatible rehabilitation, adaptive re-use, new construction, and relocation. − Policy 1.5: Require that no permit for alteration or demolition of properties identified in the Orange Historic Resources Inventory as potential historic resources shall be issued until alternatives to demolition have been duly considered. − Policy 1.6: Promote the preservation of cultural and historical resources controlled by governmental agencies, including those related to City, School District, and other agencies.
• Goal 2.0 – Preserving Historic Neighborhood Character: Identify and preserve neighborhoods that are culturally and historically significant but do not retain sufficient integrity for eligibility as a local, state, or national district. − Policy 2.1: Encourage identification and listing of Neighborhood Character Areas within the El Modena, Cypress Street Barrio, Railroad/Packinghouse Corridor, and Orange Park Acres neighborhoods.
− Policy 2.2: Promote community and visitor awareness and education concerning the unique and special history and architecture found in Neighborhood Character Areas.
− Policy 2.3: Ensure that those qualities that contribute to the historic character of designated Neighborhood Character Areas are retained through application of design guidelines consistent with the local context and key physical attributes of each neighborhood.
• Goal 3.0 – Incentives and Education: Provide incentives and expand education efforts for historic preservation.
− Policy 3.1: Expand education efforts to facilitate and encourage historic preservation and recognition of the City’s historic resources. − Policy 3.2: Provide incentives to encourage and support historic preservation. − Policy 3.3: Actively seek funding for historic preservation activities.

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− Policy 3.4: Leverage recognition of the City’s historic preservation program, participate directly in federal and state historic preservation programs, and gain access to designated historic preservation funding.
− Policy 3.5: Explore additional funding sources for maintenance and rehabilitation of historic resources.
• Goal 4.0 – Archaeological and Cultural Resources: Identify and preserve archaeological and cultural resources.
− Policy 4.1: Identify, designate, and protect historically and culturally significant archaeological resources or sites.
− Policy 4.2: Recognize the importance of Santiago Creek as an archaeological resource.
− Policy 4.3: Encourage curation of any cultural resources and artifacts recovered in the City for public education and appreciation.
− Policy 4.4: Celebrate the cultural history of the community by increasing community awareness through the design features of public projects and facilities such as parks, plazas, and community buildings. − Policy 4.5: Encourage private development to celebrate the cultural history of the community through project design.
− Policy 4.6: Provide additional resources and promotion for the Orange Public Library Historic Collection.

4.3.1.2 Existing Conditions
The following sections describe the history of the project site and discuss known cultural resources, archaeological resources, and build environment resources in or around the project’s area of potential effect (APE). The APE includes an area within a half-mile radius of the project site.

Cultural resources are the tangible or intangible remains or traces left by prehistoric or historical people who inhabited the river adjacent region. They encompass both the built (post-1769) and archaeological environments. Cultural resources are typically in protected areas near water sources and multiple ecoregions and can include Traditional Cultural Places, such as gathering areas, landmarks, and ethnographic locations.

Prehistory
The generally accepted framework recognizes four broad temporal periods or cultural horizons.

These are the Paleo-coastal or Early Man period dated to more than 10,000 years ago; the Millingstone Period, falling between 10,000 years ago and 3,000 years ago; the Intermediate Period from 3,000 years to 1,350 years ago, and the Late Prehistoric from 1,350 to 650 years ago.

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Early Man/Initial Occupation: Initial occupation is thought to have occurred between 8,500 and 11,000 years ago (6,500–9,000 B.C.) in Southern California. One recent radiocarbon date from Santa Rosa Island suggests human occupation as early as 11,500 years ago and future research may prove even earlier occupation. Early occupants were viewed as mobile foragers primarily dependent on hunting terrestrial game. This period is characterized by the presence of large projectile points and scrapers, which is an indicator of a reliance on hunting. However, recent archaeological evidence from some coastal sites indicates the systematic and intensive use of marine resources, including shellfish, during this period.

Millingstone Period: Sites dating from around 8,000 years before present (6,000 B.C.) are far more common than those from the Initial Occupation period. They typically include groundstone assemblages, indicating a probable dependence on hard seeds. At coastal sites, there is continued evidence of a wide variety of marine resource exploitation, most commonly shellfish. Some archaeologists believed that terrestrial game still provided the foundation of the diet. Some archaeologists note that the abundance of Millingstone Horizon sites suggests a sedentary settlement system, rather than a mobile foraging pattern, with central settlements and a logistically based economy supplied from special purpose camps and task sites. Sites of this time period typically yield large numbers of metates and manos, as well as unique artifacts of unknown use, called cogged stones or discoidals.

Intermediate Period: This period, from 1,000 B.C. to A.D. 750, reflects the transitional period between the Milling Stone and Late Prehistoric Horizons. At the beginning of this period important changes began to occur in settlement, technology, and subsistence intensification caused by a growing population. Changes included the increased use of acorns, elaborate fishing technology, such as the introduction of the shell fishhook, and a diverse amount of hunting tools. The apparent disuse of the Newport Coast area during this period is thought to have indicated the arrival of Shoshonean-speaking groups from the deserts to the east. Archaeologists believe these people were proto-Gabrielino and Luiseño who were not yet familiar with marine resources.

Late Prehistoric Period: The Late Prehistoric Period, beginning approximately 1,350 years B.P. (650 A.D.), reflects high population densities and complex political, social, technological, and religious systems throughout the Los Angeles Basin. Economic systems, primarily based around the growing marine fisheries, became more diverse and intensive. The growing geographic complexity of trade networks is reflected in shell-bead currency and a variety of materials traded or acquired from remote locations. Technological improvements are seen in the appearance of the bow and arrow, the plank canoe in coastal sites, and a broad variety of marine resources including mammals and fish taken in deep sea environments. Settlements became permanent towns supported by temporary camps set up at resource procurement sites. Archaeological evidence of this time period includes the presence of projectile points, soapstone bowls, callus shell beads, steatite effigies, and cremations. This period ended abruptly when Spanish colonists began establishing missions along the California coast.

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Ethnohistory
The project is situated within the ethnographic territory of the Gabrielino Indians of California.

Gabrielino lands included most of present-day Los Angeles and Orange counties, and several offshore islands. The Gabrielino spoke a Cupan language in the Takic family, which in turn is a member of the Ut o-Aztecan linguistic stock. The Gabrielino people lived in either permanent or semi-permanent villages. Known settlement locations seem to have favored two different locales:
coastal estuaries and major inland watercourses. Villages are thought to have been the focus of family life, with each individual group linked to others by paternal kinship relations. Coastal Gabrielino exploited bay and kelpbed fish, shellfish, and occasionally sea mammals. Inland groups collected and processed plants and hunted deer, bear, quail, and other terrestrial game.

Gabrielino culture was heavily affected by colonial Spanish missionary efforts long before systematic ethnographic studies could be conducted. Disease and forced participation in the mission system disrupted most traditional cultural lifeways and resulted in a catastrophic reduction of the native population. Information about their material culture and life ways is very limited and derived largely from historical sources, such as the diaries and records of early missionaries, soldiers, and explorers. While traveling through the area in 1769, Father Crespi noted the presence of a large village, Hotuuknga, upstream from present-day Olive on the north side of the Santa Ana River. Crespi wrote that 52 Indians came to greet them and accepted blankets, beads, and other goods. When he returned 2 years later the group was hostile, and the Spaniards quickly continued on their way. A small “Indian camp” was visible on the north side of Santiago Creek just west of the Glassell Street crossing as late as the 1870s.

What little ethnographic information is available suggests that the Late Prehistoric Gabrielino settlement pattern may have been characterized by a complex of central villages occupied by patrilineally constructed family lineages and smaller special purpose sites where specific resources were extracted or where food or other resources were collected for transportation back to central villages. Such a pattern is consistent with the “collector” economic model for complex huntergatherer societies such as the Gabrielino.

A discussion of the ethnohistoric and ethnographic background of the project site and surrounding areas is provided in Section 4.10, Tribal Cultural Resources, of this environmental impact report.

History
The earliest known records of European contact with Southern California Native Americans date to the mid-1500s, representing the early explorations of the Spanish. These explorations included the identification of populations from ships, but did not include direct contact. Personal contact was not made until the 1770s, when Father Garces traversed the Mojave Desert and entered coastal Southern California through the Cajon Pass.

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In 1771, the Mission San Gabriel Archangel was founded. It soon became one of the richest missions controlling all of the property in Orange County north of Aliso Creek and a large portion of Los Angeles County. The Gabrielino Indians are named after the mission.

In the late 18th Century, Felipe de Neve, Spanish Governor of California, saw the opportunity to establish a pueblo along the River Los Angeles north of the San Gabriel Mission. The primary purpose of the pueblo was to reaffirm Spain’s claim over the territory in the face of encroachments by Russia in the north and Britain from the sea. The pueblo would also help to keep Spain’s California military garrisons supplied and fed.

In August 1781, Governor de Neve, the settlers (11 men, 11 women, and 22 children), soldiers, mission priests, and a few Native Americans arrived at the new pueblo alongside the Los Angeles River. Governor de Neve recorded the date of September 4, 1781, as the official date of establishment of El Pueblo de la Reina de Los Angeles.

Americans first arrived in Los Angeles by way of nearby San Pedro, then an unimproved port.

Beginning in 1805, U.S. vessels kept up an intermittent trade with the area’s farmers, and in 1818 a crewmember, Joseph Chapman, helped construct the town’s first church. In 1826, Jedidiah Smith, a fur trapper, became the first white man to reach Los Angeles by traveling overland from the Missouri frontier.

Los Angeles was little affected by the revolution that replaced Spanish rule with that of an independent Mexican government in 1821. Mexico’s Congress declared Los Angeles the capital of California in 1835, but the provincial governor refused to move south from San Francisco.

Therefore, the City’s relative isolation and the local authority of farmers and ranchers remained unthreatened. By the 1840s, Los Angeles had become the largest settlement in Southern California.

General History of the City of Orange
The City of Orange was incorporated on April 6, 1888, under the general laws of the State of California; however, Orange dates back to 1869 when Alfred Chapman and Andrew Glassell, both lawyers, accepted 1,385 acres of land from the Rancho Santiago de Santa Ana as legal fees.

Soon thereafter, the men laid out a one square mile town with ten-acre farm lots surrounding a forty-acre central town site. The center of the town site became known as the Plaza, which has become the symbol of the community. Today, the Plaza and the majority of the original one square mile town site contain many homes and buildings dating to the early days of the City; the site is registered on the NRHP.

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General History of the City of Anaheim
The historic period in Orange County began when Don Gaspar de Portola led 62 men from San Diego north toward San Francisco. On the night of July 29, 1769, the men camped at the mouth of Brea Canyon. Along on the expedition were two Franciscan missionaries, Fathers Crespi and Gomez.

Anaheim was founded in 1857 as a colony of German farmers and vintners. George Hansen, a founding member, identified the original 1,165 acres. The City's name is a composition of “Ana” from the nearby Santa Ana River and “heim,” German for home. Those early pioneers considered this location their “home by the river.” The early settlers constructed walls and fences made from willow poles to mark the boundaries of their settlement and to keep out herds of wild cattle. Some of these fence poles took root and became gates into the colony. These first settlers were farmers, and also writers, artists, and musicians. The first public buildings were not administrative facilities, but a school and an opera house.

The North Gate is still preserved today at 775 N. Anaheim Boulevard and has been designated as a California State Landmark. Today this area comprises the City’s downtown area and surrounding historic neighborhoods bound by North, South, East, and West Streets.

Among the crops cultivated for the first few decades were grapes grown for wine. A plague in the 1870s wiped out the vineyards and, in their place, groves of citrus trees were planted. The first commercially grown oranges in Orange County were grown in Anaheim, where the growers attributed their success to the local hills which protected the fruit against the cold winds coming down from the mountains. Other crops included walnuts and chili peppers.

The City was incorporated in 1876 with a population of 881. The community grew slowly, but steadily for the next several decades. By 1920, the population was 5,526 and had become a tightknit agricultural community. In 1887, the construction of the Santa Fe depot linked Anaheim's citrus growers with the eastern United States, providing vital markets for their golden crops. The beginning of a local tradition began in 1924 with the first Anaheim Halloween Parade. Billed as the “Greatest Night Pageant West of Mardi Gras,” the annual event drew some 150,000 spectators at the height of its popularity. Visitors lined the downtown streets and thousands more viewed the pageant from the La Palma Park grandstand.

Anaheim's small-town lifestyle continued through the first half of the 20th century. Center Street was the hub of community activity, where people gathered to celebrate local events and festivities and to mark such national and international events as the end of both World Wars, the assassination of President John Kennedy, and the first steps on the moon. In 1950, the town's population had grown to 14,556.

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Project Site
Results of Records Search
Staff conducted a records search of the surrounding area using the California Historic Resources Inventory System. Data reviewed included identified reports and resources, historic maps, the NRHP, CRHR, and Built Environment Resources Directory.

Thirty-seven studies have been conducted within a 0.50-mile radius. Of those, 15 intersect with portions of the project site (Table 4.3-1, Prior Studies within 0.50-Mile Buffer).

Table 4.3-1. Prior Studies within 0.50-Mile Buffer
Study # Title Author Year
OR-00270 Description and Evaluation of Cultural Resources Within the U.S. Army Corps of Engineers' Santa Ana River Project
Leonard, Nelson N. III
and Matthew C. Hall 1975
OR-00609 Cultural Resources Report on 5 Proposed Hazardous Waste Storage Sites Located in Northern Orange County, California Desautels, Mark 1981
OR-00801 Phase II Archaeological Studies Prado Basin and the Lower Santa Ana River
Langenwalter, Paul E.
and James Brock 1985
OR-00814 ARCHAEOLOGICAL SURVEY REPORT for the Route I-5 Santa Ana Transportation Corridor, Route 405 in Orange County to Route 605 in Los Angeles County Pm 21.30/44.38; 0.00/6.85 Romani, John F.
1982
OR-00894 An Archaeological Survey of the Orange Drive-in Thester Property Orange, California
McKenna, Jeanette A. and
Hatheway, Roger G. 1988
OR-00895 Archaeological Survey Report: Villa Park-Lewis 230 Kv Transmission Line Right-Of-Way Orange County, California Taylor, Thomas T. 1988
OR-01162 Monitoring Report for the Sports Arena in the City of Anaheim Brown, Joan C. 1991 OR-01806 Cultural Resources Records Search and Literature Review Report for a Pacific Bell Mobile Services Telecommunications Facility Cm 069-12, Anaheim, Orange County, California
Mason, Roger D. 1998
OR-01836 Cultural Resource Review for Groundwater Replenishment System Program EIR/Tier I/EIS, Orange County Water
District and County Sanitation Districts of Orange County Padon, Beth 1998
OR-01900 Historical and Architectural Evaluation of Four Railroad Bridges, Lower Santa Ana River and Santiago Creek Orange County, California
Hatheway, Roger G. 1987
OR-02091 Cultural Resources Assessment for Pacific Bell Wireless Facility CM 282-02, County of Orange, California
Lapin, Philippe 2000
OR-02141 Inspection of Kinder Morgan Energy Partners Electrical Substation and Control Building Proposed Sites, Orange County Self, William 2000
OR-02200 Cultural Resources Investigation for the Nextlink Fiber Optic Project, Los Angeles and Orange Counties, California Atchley, Sara M. 2000
OR-02256 Cultural Resources Assessments for Orange County Sanitation Districts
Demcak, Carol R. 1999
OR-02354 Review of Cultural Resource Assessment/Evaluation for Cingular Wireless Site CM-282-03, Orange County, California McKenna, Jeanette A. 2001
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Table 4.3-1. Prior Studies within 0.50-Mile Buffer
Study # Title Author Year
OR-02503 Construction of a Vehicular Parking Area Within a Portion of Caltrans Right-of-way Near the Southeasterly Corner of the Orange Freeway (State Route 57) Interchange at Ball Road in Anaheim Shepard, Richard S. 2001
OR-02587 Revised Archaeological/Paleontological Monitoring Report for Arena Corporate Center Project, Contract Number PO#1058, Project #714375-01
Brown, Joan C. 2002
OR-02765 The Pinnacle at Uptown Orange McKenna, Jeanette A. 2002 OR-02828 Archaeological Monitoring During Excavations for the Westwood College Project, Anaheim, California
Brown, Joan C. 2003
OR-02911 Sunkist Gardens, City of Anaheim, Orange County, California Garcia, Kyle H. 2005 OR-03090 Taft/CA-8214 1320 South Sanderson Avenue, Anaheim, Orange County, California
Thal, Sean and Lorna
Billat
2004
OR-03097 Cultural Resources Records Search Results and Site Visit for Sprint Nextel Candidate Ca7061 (monterey), 2023 West Collins Avenue, Orange, Orange County, California
Bonner, Wayne H. 2006
OR-03108 Cultural Resource Records Search and Site Visit for Cingular Telecommunications Facility Candidate Sc-043-02 (Calvary Baptist Church), 2780 East Wagner Avenue, Anaheim, Orange County, California
Bonner, Wayne H. 2003
OR-03287 Historic Property Survey Report for Tustin Branch Trail Network, City of Orange, Orange County, California
Mason, Roger D. 2002
OR-03373 Cultural Resources Final Report of Monitoring and Findings for the Qwest Network Construction Project State of California:

Volumes I and II
Arrington, Cindy and
Nancy Sikes
2006
OR-03651 Cultural Resources Records Search and Site Visit Results for Royal Street Communications, LLC Candidate LA2658A (SCE Barre Villa Park M6-T6), 1511 North Main Street, Orange County, California
Bonner, Wayne H. and
Kathleen A. Crawford
2007
OR-03654 Direct APE Historic Architectural Assessment for Royal Street Communications, LLC Candidate LA2658A (SCE Barre Villa Park M6-T6), 1511 North Main Street, Orange, Orange County, California Bonner, Wayne H. and
Kathleen A. Crawford
2007
OR-04017 Cultural Resources Records Search and Site Visit Results for TMobile USA Candidate LA33523-A (Dupont Commercial), 2165 Dupont Drive, Anaheim, Orange County, California
Bonner, Wayne H. 2011
OR-04087 Program EIR/Tier 1 EIS, for the Groundwater Replenishment System
Salenius, Sylvia 1998
OR-04091 Cultural Resources Assessment for the Burris Basin Interpretive Loop Trail and the Lincoln Avenue Multi-Use Staging Area, City of Anaheim, Orange County, California
Fulton, Terri 2009
OR-04113 Cultural Resources Study of the Anaheim Stadium Project, AT&T Site No. OC0360, 2000 E. Gene Autry Way, Anaheim,
Orange County, California 92806
Supernowicz, Dana E. 2010
OR-04156 Draft, Phase I Archaeological Resources Survey Report, Anaheim Regional Transportation Intermodal Center Project City of Anaheim, Orange County, California
Wood, Catherine M. 2009
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Table 4.3-1. Prior Studies within 0.50-Mile Buffer
Study # Title Author Year
OR-04259 Cultural Resources Monitoring Report, Orange County Water District Groundwater Replenishment System, Orange County, California
Becker, Kenneth,
Goodman, John, Sewell,
Kristin, and Van Galder,
Sarah
2007
OR-04266 Cultural Resources Reconnaissance for the Groundwater Replenishment System, Orange County, California
Bissell, Ronald M. 2000
OR-04291 Results of Rough Grade Monitoring for the Artic Project in the City of Anaheim, California
Taft, Ryan 2012
OR-04367 Cultural Resources and Paleontological Resource -- Phase I Assessment for the Orange County Water District's Ball
Road Basin General Plan Amendment and Zone Change
Project, City of Anaheim, Orange County, California
Akyuz, Linda 2013
OR-04470 Cultural Resources Records Search and Site Visit Results for TMobile West, LLC Candidate LA02069A (CM069 Anaheim Auto Center Sign) 1383 South Auto Center Drive, Anaheim, Orange County, California
Bonner, Wayne H. 2013
Notes: Bold = Studies that intersect with the project site.

As shown in Table 4.3-2, Previously Recorded Cultural Resources within 0.50-Mile Buffer, five resources (four historic structures and one prehistoric isolate) were previously recorded within the

0.50-mile radius. One resource, the Atchison, Topeka & Santa Fe Railroad Bridge (ATS Bridge) a.k.a. Burlington Northern Santa Fe Railroad (P-30-176663) crosses over the project site.

Table 4.3-2. Previously Recorded Cultural Resources within 0.50-Mile Buffer Primary Number Chronological
Placement1 Resource Type Resource Name
P-30-100402 Prehistoric Isolate – Mano Isolate
P-30-176663 Historic Structure – Railroad Atchison, Topeka & Santa Fe Railroad (ATS Bridge) a.k.a.

Burlington Northern Santa Fe
Railroad
P-30-177113 Historic Structure- Stadium Angel Stadium of Anaheim P-30-177465 Historic Structure- Basin and Channel Fletcher Retarding Basin and Channel
P-30-177610 Historic Structure- Transmission Tower SCE M6 T6 Barre Villa Park Transmission Tower
Note: Bold = Resources that intersect with the project site. 1 This column indicates the time period for each resource type but does not determine whether a resource qualifies as a historical resource under CEQA Guidelines, Section 15064.5.

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Site Survey
A survey was conducted by Harris & Associates on July 30, 2024. The goal of this survey was to provide a constraints-level survey to identify the location of any cultural resource that may be present on site.

The survey was conducted in 5- to 10-meter transects. The project site is developed and is primarily developed and covered in disturbed habitat. Dumping on site is evident, and visibility was high due to the paved concrete walkways, dirt patches, and dried vegetation. The survey area was relatively level, and greater assessment was focused on open areas.

Historical topographic maps and historical aerials were reviewed from 1946 to 2022 (1946, 1952, 1963, 1972, 1980, 1985, 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997,1998, 1999, 2000, 2002, 2003, 2004, 2005, 2009, 2010, 2012, 2014, 2016, 2018, 2020, and 2022). From 1946 through 1952, the project site was undeveloped except for the presence of railroad tracks, agricultural uses, and Interstate 5 nearby. By 1963, major roads (Katella Avenue, Struck Avenue, Ball Road, and Taft Avenue) are present or under construction. By 1972, residential and commercial development is present in the surrounding areas including Angels Stadium. State Route 57 is present by 1980.

Development in the area remains essentially static through 2022.

The Santa Ana River has been heavily modified on both its east and west banks. The river channel was constructed in 1995 (PACE 2025) as a trapezoidal soft-bottom storm drain channel and its bottom is routinely graded for maintenance reasons such as flood control, sediment and erosion management, and stormwater conveyance.

Historical Resources
Harris & Associates conducted a survey on July 30, 2024, to provide a constraints-level survey to identify the location of any cultural resource that may be present on site. No historical resources were identified during the cultural survey. The APE is developed and has been historically disturbed.

Archaeological Resources
The survey conducted by Harris & Associates on July 30, 2024, did not identify any archaeological resources on site.

Tribal Cultural Resources
The NAHC was contacted for a Sacred Lands File Check to determine if sacred lands are present on site. The NAHC responded that the check yielded no previously known Native American sacred sites.

Outreach has been conducted to the list of Tribes listed in the NAHC response letter (refer to Appendix E). No responses were received from the Tribes for the preparation of the Cultural Resources Survey Letter Report. A detailed discussion of the TCRs is provided in Section 4.10 of this EIR.

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4.3.2 Thresholds of Significance
According to Appendix G of the CEQA Guidelines, the project would have a significant impact on cultural resources if it would:
• Threshold CUL-1: Cause a substantial adverse change in the significance of a historical resource pursuant to Section 15064.5.
• Threshold CUL-2: Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section 15064.5.
• Threshold CUL-3: Disturb any human remains, including those interred outside of dedicated cemeteries.

The Initial Study (Appendix A to the EIR) determined that the following thresholds would have less than significant or no impact, and this environmental topic will not be addressed further in this section of the Draft EIR:
• Threshold CUL-3

4.3.3 Plans, Programs, and Policies
This section addresses plans, programs, and policies relevant to the project.

PPP CUL-1: The project shall comply with Section 7050.5 of the California Health and Safety Code in the event of discovery or recognition of any human remains in the project site. This provision states that no further disturbance would occur until the County Coroner makes a determination of origin and disposition pursuant to California Public Resources Code, Section 5097.98.

4.3.4 Environmental Impacts
The following sections address various potential impacts relating to cultural resources that could result from implementation of the project.

4.3.4.1 Threshold CUL-1: Historical Resources
Impact Analysis
The project site is not designated as a historic resource nor is the site proposed as a historic resource. Additionally, no listed or designated historical resources are in proximity to the site.

According to the records search using the California Historic Resources Inventory System, five resources (four historic structures and one prehistoric isolate) were previously recorded within the

0.50-mile radius. One resource, the ATS Bridge, crosses over the project site. The ATS Bridge was evaluated in 1987 by Roger Hatheway. According to the study:

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The existing structure is not the original Santa Fe railroad bridge built to cross the Santa Ana River at this point. The earlier structure was replaced in 1916 and again in 1938 as a result of flood damage. The present structure is interesting, however, in that it is of a seemingly inordinate length.

An answer to this problem is found through an examination of additional U.S. Geological Survey Maps. The 1950 edition clearly shows that the river channel widened considerably at this point.

This may have been a result of either the 1916 or 1938 floods. The river channel has since been narrowed considerably, hence the anomaly between the bridge length and width of the river channel. The present bridge is, therefore, of engineering interest, although it is not of a unique design, method of construction, or of outstanding historical interest.

The bridge does not possess a high degree of integrity as the original structure was replaced more than once. The present structure contains portions of a 1916 bridge but is primarily a 1938 structure. The setting has also been altered, including the narrowing of the river channel. The majority of the structure is not more than 50 years old. This fact should, however, not be a major determining factor as the bridge is only one year less old than the 50-year eligibility date. The structure does not possess high artistic or design value as it is a simple standardized well deck girder common throughout California. The structure itself does not have significant historical associations. It is part of a major and historical transportation system but was not one of the first or most significant elements of this system. The structure does represent unusual scale in terms of its overall length. The structure is not an unusual or rare surviving example of its type.

The study determined that the ATS Bridge did not meet criteria for eligibility to the NRHP.

During the survey conducted by Harris & Associates on July 30, 2024. Additionally, historic topographic maps and historical aerials were reviewed. The ATS Bridge is present in the southern portion of the project site. No changes to the bridge were identified (refer to photos 21, 39, and 44 in the Cultural Resources Survey Letter Report, included as Appendix E) and no new information was identified during the survey. The ATS Bridge is not eligible for listing to either the NRHP or CRHR; as such, it is not significant under CEQA. It will not be impacted by the project because it crosses over the project site. No historical resources were identified during the pedestrian survey.

The project includes development of 17 multi-purpose improvements that include Active Transportation (AT), River Activation (RA), and Community Amenities (CA) improvements, which will work to re-establish the river corridor as a place of interconnectivity and maximize its use. The site does not contain any existing structures that are 50 years old that would meet the criteria listed above. Therefore, redevelopment of the project site would not impact historical resources; no impacts would occur.

Level of Significance Before Mitigation: No impact.

Mitigation Measures: No mitigation measures are required.

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4.3.4.2 Threshold CUL-2: Archaeological Resources
Impact Analysis
An archaeological field survey was conducted on July 30, 2024, to determine if cultural resources exist on the project site. The survey was completed in accordance with CEQA significance evaluation criteria. According to the Cultural Resources Survey Letter Report, included as Appendix E, no resources were recorded on the project site. There is little potential for archaeological resources to the present or disturbed by the proposed development. Based on the records search and the results of the field survey, archaeological resources are not expected to occur on the project site.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.3.5 Cumulative Impacts
This section addresses various potential cumulative impacts relating to cultural resources that could result from implementation of the project.

4.3.5.1 Cumulative Thresholds CUL-1 and CUL-2: Historical and Archaeological Resources
Direct impacts to on-site cultural resources are site-specific. Each development proposal received by the City undergoes environmental review and would be subject to the same resource protection requirements as the project as outlined in the City of Orange General Plan and the City of Anaheim General Plan, as applicable. If there is a potential for significant impacts on cultural resources, an investigation will be required to determine the nature and extent of the resources and to identify appropriate mitigation measures, including requirements such as those identified in this section.

Based on the information presented in the required site-specific cultural resource studies, construction activities associated with the project would not impact any known prehistoric archaeological resources and the likelihood of uncovering previously unknown archaeological resources during project construction are low. As such, the project would not result in a cumulatively considerable contribution to a significant cumulative impact to archaeological resources.

4.3.6 Level of Significance Before Mitigation
The following thresholds would be less than significant:
• Threshold CUL-1: Implementation of the project would not adversely impact historical resources.
• Threshold CUL-2: Implementation of the project would not adversely impact archaeological resources.

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4.3.7 Mitigation Measures
No mitigation measures are required.

4.3.8 Level of Significance After Mitigation
Not applicable.

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Section 4.4: Geology and Soils
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4.4 Geology and Soils
This section evaluates the potential for impacts relating to geology and soils from implementation of the OC River Walk Project (project).

The analysis in this section is based on the Preliminary Geotechnical Evaluation prepared by Ninyo & Moore (2024). A complete copy of the report is included in Appendix F, Geotech Report.

4.4.1 Environmental Setting

4.4.1.1 Regulatory Setting
This section describes the federal, state, and local regulatory framework adopted to address geology and soils.

Federal
National Earthquake Hazards Reduction Act
The National Earthquake Hazards Reduction Act was passed to reduce the risks to life and property resulting from earthquakes. The act established the National Earthquake Hazards Reduction Program (NEHRP). The mission of NEHRP includes improved understanding, characterization, and prediction of hazards and vulnerabilities; improved building codes and land use practices; risk reduction through post-earthquake investigations and education; development and improvement of design and construction techniques; improved mitigation capacity; and accelerated application of research results. The NEHRP designates the Federal Emergency Management Agency as the lead agency of the program and assigns planning, coordinating, and reporting responsibilities.

Other NEHRP agencies include the National Institute of Standards and Technology, National Science Foundation, and the U.S. Geological Survey.

Antiquities Act (16 USC 431–433)
The Antiquities Act of 1906 states, in part, the following:

That any person who shall appropriate, excavate, injure or destroy any historic or prehistoric ruin or monument, or any object of antiquity, situated on lands owned or controlled by the Government of the United States, without the permission of the Secretary of the Department of the Government having jurisdiction over the lands on which said antiquities are situated, shall upon conviction, be fined in a sum of not more than five hundred dollars or be imprisoned for a period of not more than ninety days, or shall suffer both fine and imprisonment, in the discretion of the court.

Although there is no specific mention of natural or paleontological resources in the act itself or in the act’s uniform rules and regulations (43 CFR 3), the term “objects of antiquity” has been Section 4.4: Geology and Soils
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interpreted to include fossils by the National Park Service, Bureau of Land Management, U.S.

Forest Service, and other federal agencies. Permits to collect fossils on lands administered by federal agencies are authorized under this act. However, due to the large gray areas left open to interpretation due to the imprecision of the wording, agencies are hesitant to interpret this act as governing paleontological resources.

State
Alquist-Priolo Earthquake Fault Zoning Act (California Public Resources Code, Section 2621 et seq.)
The Alquist-Priolo Earthquake Fault Zoning Act was signed into state law in 1972. Its primary purpose is to mitigate the hazard of fault rupture by prohibiting the location of structures for human occupancy across the trace of an active fault. The act delineates “Earthquake Fault Zones” along faults that are “sufficiently active” and “well defined.” The act also requires that cities and counties withhold development permits for sites within an earthquake fault zone until geologic investigations demonstrate that the sites are not threatened by surface displacement from future faulting. Pursuant to this act, structures for human occupancy are not allowed within 50 feet of the trace of an active fault.

California Building Code (California Code of Regulations, Title 14, Part 2) Current law states that every local agency enforcing building regulations, such as cities and counties, must adopt the provisions of the California Building Code (CBC) within 180 days of its publication. The publication date of the CBC is established by the California Building Standards Commission, and the code is also known as Title 24, Part 2, of the California Code of Regulations.

The most recent building standard adopted by the legislature and used throughout the state is the 2019 version of the CBC (effective January 1, 2020), often with local, more restrictive amendments that are based on local geographic, topographic, or climatic conditions. These codes provide minimum standards to protect property and public safety by regulating the design and construction of excavations, foundations, building frames, retaining walls, and other building elements to mitigate the effects of seismic shaking and adverse soil conditions. The CBC contains provisions for earthquake safety based on factors including occupancy type, types of soil and rock on site, and strength of ground shaking with specified probability of occurring at a site.

California Code of Regulations, Title 14, Division 3, Chapter 1 California Code of Regulations, Title 14, Division 3, Chapter 1, prohibits any person from destroying, disturbing, or mutilating geological features including paleontological resources. This applies to excavation and grading activities that would be performed under the project.

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Natural Hazards Disclosure Act (California Civil Code, Section 1103.2) The Natural Hazards Disclosure Act requires that sellers of real property and their agents provide prospective buyers with a Natural Hazard Disclosure Statement when the property being sold lies within one or more state-mapped hazard areas, including a seismic hazard zone. California law also requires that, when houses built before 1960 are sold, the seller must give the buyer a completed earthquake hazards disclosure report and the booklet The Homeowners Guide to Earthquake Safety.

This publication was written and adopted by the California Seismic Safety Commission.

Seismic Hazard Mapping Act (California Public Resources Code, Sections 2690–2699.6) The Seismic Hazard Mapping Act was adopted by the state in 1990 to protect the public from the effects of non-surface fault rupture earthquake hazards, including strong ground shaking, liquefaction, seismically induced landslides, or other ground failure caused by earthquakes. The goal of the act is to minimize loss of life and property by identifying and mitigating seismic hazards. The California Geological Survey prepares and provides local governments with seismic hazard zone maps that identify areas susceptible to amplified shaking, liquefaction, earthquakeinduced landslides, and other ground failures. The act requires responsible agencies to only approve projects within seismic hazard zones following a site-specific investigation to determine if the hazard is present, and if so, the inclusion of appropriate mitigation. In addition, the act requires real estate sellers and agents at the time of sale to disclose if a property is in one of the designated seismic hazard zones.

California Code of Regulations, Title 14, Article 10, Seismic Hazards Mapping (Section 3720 et seq.)
These regulations require city, county, and state agencies to identify and amp seismic hazard zones and to mitigate seismic hazards to protect public health and safety in accordance with the provisions of the Public Resources Code, Section 2690 et seq. (Seismic Hazards Mapping Act). Within seismic hazard zones, a project is approved only when the nature and severity of the seismic hazards at the site have been evaluated in a geotechnical report and appropriate mitigation measures have been proposed.

Division of Mines and Geology, Special Publication 117
With the implementation of the Seismic Hazards Mapping Act in California, general guidelines for evaluating and mitigating seismic hazards in California were published by the California Department of Conservation, Division of Mines and Geology in 1997 as Special Publication 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California. This document constitutes the guidelines for evaluating seismic hazards other than surface fault rupture, and for recommending mitigation measures as required by Public Resources Code, Section 2695(a). The objectives of these guidelines are twofold: 1) To assist in the evaluation and mitigation of earthquake-related hazards for projects within designated zones of required investigations; and 2) to promote uniform and effective statewide implementation of the evaluation and mitigation elements of the Seismic Hazards Mapping Act.

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Soils Investigation Requirements
California Health and Safety Code, Sections 17953–17955, and CBC Section 1802 include requirements for soils investigations for subdivisions requiring tentative and final maps and for other specified types of structures. Testing of samples from subsurface investigations, such as from borings or test pits, is required. Studies must be done as needed to evaluate slope stability, soil strength, position and adequacy of load-bearing soils, the effect of moisture variation on loadbearing capacity, compressibility, liquefaction, differential settlement, and expansiveness.

Local
Anaheim Municipal Code, Title 17
Title 17 of the Anaheim Municipal Code, Land Development and Resources, outlines the City of Anaheim’s (City’s) procedures, necessary permits, and standards with regard to development, which projects are subject to. This includes risk reduction with regard to geological hazards.

Anaheim General Plan Safety Element
The Safety Element of the General Plan has established the following policies related to development in areas with various geological conditions. • Minimize the risk to life and property through the identification of potentially hazardous geologic areas.
• Require geologic and geotechnical investigations in areas of potential seismic or geologic hazards as part of the environmental and/or development review process for all structures.
• Enforce structural setbacks from faults and other geologic hazards identified during the development review process.
• Enforce the requirements of the California Seismic Hazards Mapping and Alquist Priolo Earthquake Fault Zoning Acts when siting, evaluating, and constructing projects within the City.
• Require that lifelines (i.e., water, sewer, electrical, gas facilities, and communication and transportation facilities that are needed in the event of a hazard event or natural disaster) crossing a fault or located within a geologic hazard be designed to resist damage resulting from a hazard event.
• Require new construction, redevelopment, and major remodels located within potential landslide areas be evaluated for site stability, including the potential impact to other properties, during project design and review.

City of Orange Municipal Code
The City of Orange, Municipal Code, Chapter 16.40, Grading Requirements, incorporates the City of Orange Manual of Grading and the Guidelines for Landform Grading and Planting to set Section 4.4: Geology and Soils
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forth the rules and regulations to control erosion, water quality, excavation, grading and earthwork construction, including cuts and fills; establishes the administrative procedure for the issuance of grading permits and provides for review and approval of plans and the inspection of grading construction.

City of Orange General Plan Public Safety Element
The Safety Element of the General Plan has established the following goal and policies to protect residents from seismic hazards and other geologic constraints. • Goal 1.0: Protect residents and businesses from seismic hazards and other geologic constraints.
− Policy 1.1: Minimize the potential loss of life and damage to structures that may result from an earthquake.
− Policy 1.2: Educate and train individuals and neighborhoods how to respond to emergency situations.
− Policy 1.3: Participate in federal, state, and local earthquake preparedness and emergency response programs.

4.4.1.2 Existing Conditions
The following existing conditions are based on the Preliminary Geotechnical Evaluation, Appendix F of this Draft Environmental Impact Report (EIR), which mainly reviewed readily available existing geotechnical information and as-built drawings pertinent to the project and provided engineering analyses of the compiled data. Numerous previous geotechnical studies have been prepared near the project site that include exploratory borings and laboratory testing, and their results are included as part of the Preliminary Geotechnical Evaluation. It should be noted that a supplemental geotechnical engineering analyses will be performed, and an updated geotechnical evaluation report will be prepared once site-specific borings are performed according to the approved Drilled Program Plan.1
Regional Geology
The project site is located within the southerly portion of the Los Angeles Basin, which is included in the Peninsular Ranges Geomorphic Province. The Los Angeles Basin has been divided into four structural blocks, which are generally bounded by prominent fault systems, and includes the Northwestern Block, the Southwestern Block, the Central Block, and the Northeastern block. The project site is located within the Central Block, which is bordered on the west by the NewportInglewood fault, on the east by the Whittier-Elsinore fault, on the north by the Malibu Coast-Santa 1 To conduct borings within earth embankments under the jurisdiction of the U.S. Army Corps of Engineers (USACE), approval of a Drilling Program Plan by USACE is required. Niyon & Moore prepared the Drilling Program Plan for the project on March 31, 2023. However, since the plan has not yet been approved by USACE, no subsurface exploration has been performed within the earth embankment.

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Monica-Raymond fault, and on the south by the San Joaquin Hills and the Santa Ana Mountains.

The Central Block is characterized by thick sequences of alluvium overlying basement rocks at depth. Basement rocks exposed in some oil wells along the margins of the Central Block consist of sedimentary Jurassic-age rocks, late Cretaceous-age plutonic rocks, and late Cretaceous to Pleistocene-age sedimentary rocks. Regional geologic mapping indicates that the area is underlain by Holocene-age alluvial wash and fan deposits generally consisting of gravel, sand, and silt. The Holocene-age alluvial sediments have an estimated thickness of approximately 110 to 130 feet.

Project Site Geology
The subsurface stratigraphy of the project site generally consists of artificial fill underlain by alluvium. Artificial fill materials are variable and generally consist of sand, sand with silt, silty sand, sandy silt, silt, clayey silt, and silty clay with varying densities and consistencies. The alluvium is comprised of coarse to fine sediments ranging from silty sand, sand with silt, sand, gravelly sand, silty gravel, clayey gravel, and sandy gravel, with scattered cobbles, and clay, silty clay, clayey silt, silt, and sandy silt. The materials are generally moist to wet with consistencies that ranged from very loose to very dense in the granular non-plastic soils and very soft to hard in the fine plastic soils. The soils comprising the existing fill and alluvial deposits can vary significantly both laterally and with depth.

Faulting and Seismicity
The project site is not within the Alquist-Priolo Special Studies Zone. The nearest mapped active fault to the project site is the Peralta Hills fault located approximately 3 miles north of the project site.

Seismically Induced Ground Shaking
The project site is in a seismically active area, as is the majority of Southern California. Considering the proximity of the project site to active faults capable of producing a maximum moment magnitude of 6.0 or more, the project site has a high potential for experiencing strong ground motion.

Liquefication
Liquefaction is the phenomenon in which loosely deposited, saturated granular soils (located below the water table) undergo rapid loss of shear strength due to development of excess pore pressure during strong earthquake-induced ground shaking. Ground shaking of sufficient duration results in the loss of grain-to-grain contact due to rapid rise in pore water pressure and it eventually causes the soil to behave as a fluid for a short period of time. Liquefaction is known generally to occur in saturated or near-saturated cohesionless soils at depths shallower than 50 feet below the ground surface. Liquefaction is also known to occur in relatively fine-grained soils (i.e., sandy silt and clayey silt). Factors known to influence liquefaction potential include composition and thickness of soil layers, grain size, relative density, groundwater level, degree of saturation, and both intensity and duration of ground shaking. As shown on Figure 8 of the Geotechnical Evaluation (included in Section 4.4: Geology and Soils
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Appendix F of this Draft EIR), the project site is located in an area mapped as being potentially susceptible to liquefaction per the State of California Seismic Hazard Zones maps.

Lateral Spreading
Lateral spreading of the ground surface during an earthquake usually takes place along weak shear zones that have formed within a liquefiable soil layer. Lateral spread has generally been observed to take place in the direction of a free-face (i.e., retaining wall, slope, and channel), but has also been observed to a lesser extent on ground surfaces with very gentle slopes. It typically results when ground shaking moves soil toward an area where soil integrity is weak or unsupported. For sites located in proximity to a free-face, the amount of lateral ground displacement is strongly correlated with the distance of the site from the free-face. The project site is located within the free-faces of the Santa Ana River, and there is a potential for seismically induced lateral spread at the site.

Landslides
A landslide is defined as the movement of a mass of rock, debris, or earth down a slope. It can happen suddenly or more slowly over long periods of time. Landslides occur when slopes become destabilized, typically after heavy rains. If precipitation saturates soils, they can become unstable, or landslides can occur when significant erosion from rainfall destabilizes the ground. Slopes that have recently burned face a greater risk from rain induced landslides, as the loss of vegetation can de-stabilize the earth. Earthquakes may also be a source of landslides as the shaking can destabilize steep hillsides covered in loose soils and weak rock layers. The project site is not identified as being within high landslide susceptibility areas mapped by the California Geological Survey with Deep Seated Landslide Potential (Anaheim 2022; Orange 2022).

Subsidence
Ground subsidence is the gradual settling or sinking of the ground, usually associated with the extraction of oil, gas, or groundwater from below the ground surface or the organic decomposition of peat deposits with a resultant loss in volume. The principal causes of subsidence are aquifersystem compaction, drainage of organic soils, underground mining, and natural compaction. The City of Anaheim Local Hazard Mitigation Plan (2022) and the City of Orange Local Hazard Mitigation Plan (2016) do not identify subsidence as a hazard of concern for either city.

Expansive Soils
Soils with a high expansion potential increase in volume with the addition of water. Soil expansion can be detrimental to foundations, concrete slabs, flatwork, and pavement. The Preliminary Geotechnical Evaluation (Appendix F to the Draft EIR) indicated that non-expansive can be defined as soils having an expansion index of 20 or less in accordance with ASTM D 4829.

According to previous laboratory testing results included as part of the Preliminary Geotechnical Evaluation, soils for nearby projects had very low expansion potential with zero expansion index.

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4.4.2 Thresholds of Significance
According to Appendix G of the California Environmental Quality Act (CEQA) Guidelines, the project would have a significant impact on geology and soils if it would:
• Threshold GEO-1: Directly or indirectly cause potential substantial adverse effects, including the risk of loss, injury, or death involving:
i. Rupture of a known earthquake fault, as delineated on the most recent AlquistPriolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other substantial evidence of a known fault. Refer to Division of Mines and Geology Special Publication 42.
ii. Strong seismic ground shaking.
iii. Seismic-related ground failure, including liquefaction. iv. Landslides.
• Threshold GEO-2: Result in substantial soil erosion or the loss of topsoil. • Threshold GEO-3: Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction or collapse. • Threshold GEO-4: Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial direct or indirect risks to life or property. • Threshold GEO-5: Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water.
• Threshold GEO-6: Directly or indirectly destroy a unique paleontological resource or site or unique geologic feature.

The Initial Study (Appendix A to the Draft EIR) determined that the following thresholds would have less than significant or no impact, and these environmental topics will not be addressed further in this section of the Draft EIR.
• Threshold GEO-5
• Threshold GEO-6

4.4.3 Plans, Programs, and Policies
This section addresses plans, programs, and policies related to geology that are relevant to the project.

PPP GEO-1 The project will be designed and constructed in accordance with the California Building Code (CBC) adopted by the City of Anaheim and the City of Orange. The project shall comply with applicable development standards and ordinances and by the most recent building and seismic codes in effect at the time of project design for the respective cities. In accordance with Section 1803.2 of the CBC, a Section 4.4: Geology and Soils
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geotechnical investigation is required that must evaluate soil classification, slope stability, soil strength, position and adequacy of load-bearing soils, the effect of moisture variation on soil-bearing capacity, compressibility, liquefaction, and expansiveness, as determined by the applicable approval authority. The geotechnical investigation must be prepared by registered professionals (i.e., California Registered Civil Engineer or Certified Engineering Geologist).

Recommendations of the report pertaining to structural design and construction recommendations for earthwork, grading, slopes, foundations, pavements, and other necessary geologic and seismic considerations must be incorporated into the design and construction of the project.

PPP GEO-2 The project will be designed and constructed by incorporating recommendations contained in the Preliminary Geotechnical Evaluation prepared by Ninyo & Moore dated October 11, 2024 (Appendix F to the Draft Environmental Impact Report) and any subsequent updates prepared for the project to implement PPP GEO-1. In addition to the specific earthwork-, foundations-, retaining walls, pavement-, trails-, corrosivity-, concrete placement-, and drainage-related recommendations, the Preliminary Geotechnical Evaluation also contains the following construction monitoring programs to monitor ground vibrations, ground surface settlement, and lateral movement of shoring support systems. These monitoring programs will be in-place and conducted prior to the start of construction and the resulting data will be reviewed and evaluated during construction and be shown on all grading and building plans.

Documentation of Existing Conditions. Conduct pre-construction condition surveys on structures and railroad crossings within approximately 50 feet of the proposed excavations prior to construction. This distance will be extended to 100 feet adjacent to proposed excavations if driven and vibratory sheet or soldier piles are installed. This survey will include locating existing cracks and measuring widths of cracks, in combination with video documentation of existing conditions.

Interviews will be conducted with utility owners so that existing knowledge about the age, type, and maintenance history of affected utilities is available prior to construction.

Construction Vibrations. Monitor the vibration by using seismographs in the early stages. Seismographs will be located near structures and improvements next to the construction activities. Additional seismographs will be located at various structures and improvements farther from the construction activities to monitor vibrations as a function of distance from the sites. Periodic vibration monitoring will be conducted during other construction activities. After review of the data Section 4.4: Geology and Soils
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obtained, reduce the number of seismographs at the discretion of the governing/approval agencies/entities and the qualified geotechnical consultant.

Ground Surface Settlement. Install arrays of ground surface settlement points around the proposed excavations. The construction contractor will submit a monitoring plan showing the proposed locations of settlement points for review and approval by the Project Engineer. The construction contractor will be responsible for maintaining total settlement at any survey point to less than 0.5 inch. If the settlement reaches this limit, further review of construction methodologies be performed and appropriate changes be made.

Lateral Movement for Shoring Support System. Install inclinometers or establish survey points behind excavations next to existing slopes. The inclinometers or survey points will be monitored and evaluated daily during excavation activities to provide an advanced warning system of potential problems. The shoring system will be designed to limit the ground settlement behind the shoring system to 0.5 inch or less to reduce the potential for distress to adjacent structures/improvements.

If settlements reach 0.25 inch, a review of the construction contractor’s methods will be performed and appropriate changes be made, if needed.

Groundwater Monitoring. If construction dewatering is performed, the construction contractor will install groundwater monitoring wells to monitor water levels outside the excavations. The monitoring wells will be installed at locations that will be accessible during construction. The groundwater levels will be monitored daily during dewatering as appropriate.

PPP GEO-3 All bridges shall be designed and constructed in accordance with the latest edition of the American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridge Design Specifications with California Amendments, the latest versions of the California Department of Transportation Standard Plans, Seismic Desing Criteria, and Geotechnical Manual, as required for various elements of the project, as determined by the applicable approval authority.

PPP HYD-1 The project is required to be developed in compliance with the following state, regional, and local regulations concerning grading, stormwater, and water quality control, as determined by the applicable approval authority:
• National Pollutant Discharge Elimination System General Construction Permit:

Notice of Intent and Storm Water Pollution Prevention Plan Requirements • State Water Resources Control Board General Industrial Activities Storm Water Permit
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• Santa Ana Regional Water Quality Control Board Waste Discharge Permits and Water Quality Certifications
• Orange County Grading Manual
• Orange County Grading and Excavation Code
• Orange County Municipal Separate Storm Sewer Systems Permit • Orange County Model Water Quality Management Plan and Technical Guidance Document
• Orange County Drainage Area Management Plan: New Development/ Significant Redevelopment Program
• Orange County Hydrology Manual and 1996 Addendum
• Orange County Water District Groundwater Replenishment Program • Orange County Flood Control District Local Implementation Plan 2019 • City of Anaheim and City of Orange Municipal Codes
• City of Anaheim Grading Design Manual
• Anaheim Master Plan of Drainages North and West Santa Ana Tributaries • American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridge Design Specifications with California Amendments
• California Department of Transportation Standard Plans • California Department of Transportation Seismic Desing Criteria • California Department of Transportation Geotechnical Manual

4.4.4 Environmental Impacts
The following sections address various potential impacts relating to geology and soils that could result from implementation of the project.

4.4.4.1 Threshold GEO-1.i: Exposure to Seismic-Related Hazards – Rupture of a Known Earthquake Fault
Impact Analysis
The Alquist-Priolo Special Study Zone Map does not delineate any known earthquake fault on the project site (Ninyo & Moore 2024; City of Anaheim 2022; City of Orange 2010). Therefore, the project would not directly or indirectly cause substantial adverse effects involving rupture of a known earthquake fault as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map.

Level of Significance Before Mitigation: No impact.

Mitigation Measures: No mitigation measures are required.

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4.4.4.2 Threshold GEO-1.ii: Exposure to Seismic-Related Hazards – Ground Shaking
Impact Analysis
As with all Southern California, the project site has the potential for strong seismic shaking. The nearest mapped active fault to the project site is the Peralta Hills fault located approximately 3 miles north of the project site. Although no active faults are located within the project site, there are other regionally active faults that could produce ground shaking at the project site during an earthquake (Ninyo & Moore 2024). However, the project involves impoundments, storm drain diversions, embankments, retaining walls, pump stations, trails and undercrossings, trail improvements, bridges, and enhanced community amenities, which would not involve development of any habitable structures. Additionally, the project would be constructed using appropriate foundation methods for the planned improvements, shallow foundations 2 for impoundment structures, pump stations, retaining walls, amphitheater seating walls, drop structures, and grade control structures, and steel HP pile or cast-in-drilled-hole (CIDH) pile foundations for the bridges. During construction of proposed improvements, remedial grading consisting of the excavation and recompaction of the existing undocumented fill or loose natural materials would be required pursuant to the recommendations contained in the Preliminary Geotechnical Evaluation (Appendix F) or any subsequent updates. In addition, requirements of the appropriate governing jurisdictions and applicable building codes would be considered in the design of the structures for seismic safety, such as ground shaking. Some of the applicable building and infrastructure regulations include the CBC, American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridge Design Specifications with California Amendments, the latest versions of the California Department of Transportation Standard Plans, Seismic Desing Criteria, and Geotechnical Manual, California Public Utilities Commission’s General Orders, Rules of Practice and Procedures, Public Utilities Code, and the Manual on Uniform Traffic Control Devices, the City of Anaheim Municipal Code, and the City of Orange Municipal Code. Therefore, impacts from strong ground shaking would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required. 2 A shallow foundation is a type of foundation that transfers building loads to the earth near the surface, typically at a depth less than 3 meters (or less than the width of the foundation), rather than relying on deeper soil or rock layers Shallow foundations, including spread footings and mat foundations are proposed. Spread footings consist of concrete slabs or pads that support individual columns or walls. They are typically suitable for light to moderate loads and stable soils with adequate bearing capacity.

Mat foundations, also known as raft foundations, are a type of shallow foundation that covers the entire area of the structure.

They act as a single unit that supports multiple columns or walls. They are typically suitable for heavy loads and poor soils with low bearing capacity.

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4.4.4.3 Threshold GEO-1.iii: Exposure to Seismic-Related Hazards – Liquefaction Impact Analysis
The project site is located in an area mapped as being potentially susceptible to liquefaction per the State of California Seismic Hazard Zones maps (Ninyo & Moore 2024). The project involves impoundments, storm drain diversions, embankments, retaining walls, pump stations, trails and undercrossings, trail improvements, bridges, and enhanced community amenities that require ground-disturbing activities, including but not limited to excavation, recompaction, mat and spread footing foundations, and steel H-pile or CIDH pile installation for the pedestrian bridge foundations.

Pursuant to California Code of Regulations, Section 3724, the project is required to be designed and constructed in compliance with the recommendations of the geotechnical evaluations prepared for the project, the Preliminary Geotechnical Evaluation (Appendix F).

The Preliminary Geotechnical Evaluation indicates that the project would require remedial grading and recompaction of the existing undocumented fill or loose natural materials for the purposes of bridge foundations. Excavation and recompaction would extend to the depth of the undocumented fill to expose firm and unyielding alluvium or to a depth that will provide 2 to 3 feet of compacted fill below the bottom of the proposed foundations, whichever is deeper. For improvements constructed within the Santa Ana River channel, it is anticipated that the base of the improvements would extend approximately 2 feet below the potential scour depth unless the improvements are designed to prevent scour. If the remedial grading bottom is unstable under heavy equipment loads, additional excavation would be provided as needed to stabilize the bottom. Recompaction of materials would increase the stability of existing soil and reduce susceptibility to liquefaction. The Preliminary Geotechnical Evaluation also recommended that the removal and recompaction work include scarifying, moisture-conditioning, and compacting the exposed subgrade soils to a depth of 8 inches or more, and placing the excavated materials back as compacted fill. Trenches and excavations would be designed and constructed in accordance with the Occupational Safety and Health Administration (OSHA) regulations that provide shoring design parameters for excavations and trenches up to 20 feet deep based on the soil types encountered. Although not anticipated, if trenches over 20 feet deep are needed, they would be designed by the contractor’s engineer based on site-specific geotechnical analyses. The project would be designed in accordance with structural considerations and recommendations contained in the Preliminary Geotechnical Evaluation.

The Preliminary Geological Evaluation determined that the project is feasible from a geotechnical perspective. In addition, the project is required to adhere to the requirements of the appropriate governing jurisdictions and applicable building codes, including geologic stability for liquefaction.

Some of the applicable building and infrastructure regulations include the CBC, American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridge Design Specifications with California Amendments, the latest versions of the California Section 4.4: Geology and Soils
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Department of Transportation Standard Plans, Seismic Desing Criteria, and Geotechnical Manual, California Public Utilities Commission’s General Orders, Rules of Practice and Procedures, Public Utilities Code, and the Manual on Uniform Traffic Control Devices, the City of Anaheim Municipal Code, and the City of Orange Municipal Code. Therefore, impacts from liquefaction would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.4.4.4 Threshold GEO-1.iv: Exposure to Seismic-Related Hazards – Landslide Impact Analysis
The Preliminary Geotechnical Evaluation (Appendix F) concluded that the project site is not located in an area considered susceptible to landsliding. The project site is not identified as being within high landslide susceptibility areas mapped by the California Geological Survey with Deep Seated Landslide Potential (Anaheim 2022, Orange 2022). Therefore, no impacts from landslide would occur.

Level of Significance Before Mitigation: No Impact.

Mitigation Measures: No mitigation measures are required.

4.4.4.5 Threshold GEO-2: Soil Erosion or Topsoil Loss
Impact Analysis
Erosion is a natural process of the movement of soil from place to place. The main natural agents of erosion in the region are flowing water and wind. Erosion can be accelerated dramatically by ground-disturbing activities if effective erosion control measures are not used. Soil can be carried off construction sites or bare land by wind and water and tracked off construction sites by vehicles.

The project has the potential to result in soil erosion impacts during construction and operation.

Construction-Related Erosion
Various project-related improvements would result in ground-disturbing activities during construction, exposing soils and potentially result in in the loss of topsoil. The project involves more than one-acre of ground-disturbing activities within and adjacent to Santa Ana River, riverbed, and embankments on both sides of the river. However, the project is required to comply with the National Pollutant Discharge Elimination System permit from the State Water Resources Control Board, including submittal of a Notice of Intent and preparation of a Storm Water Pollution Prevention Plan, which will specify best management practices (BMPs) to minimize stormwater pollution from project construction, including erosion and sediment. The project construction contractor would implement the specified BMPs to manage erosion, fugitive dust, and stormwater related issues. With Section 4.4: Geology and Soils
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implementation of standard construction BMPs in accordance with a Storm Water Pollution Prevention Plan, the project’s construction would result in less than significant impacts related to soil erosion and loss of topsoil. Additionally, the project would comply with the City of Anaheim General Plan Green Element Policies 7.1-1 and 7.1-2, and the City of Orange Natural Resources Element Policies 2.13 through 2.15 to reduce erosion, siltation, and other run-off impacts. With these mandatory BMPs, construction-related stormwater impacts would be less than significant.

Operational Impacts
According to the Preliminary Geotechnical Evaluation (Appendix F of this EIR), soils on the project site and surrounding area vary in susceptibility to water erosion. This is due to the variation in soil stratigraphy, and site-specific borings would be required to prior to grading activities.

Following construction, the project site would consist of paved and landscaped areas. As identified in the Preliminary Geotechnical Evaluation, the project site is located within a “Zone A” designated flood area (FEMA 2009). Specifically, the lower terrace path, and portions of the middle terrace path and amphitheater seating are planned at elevations that are lower than the 100- year flood level. Soil and topsoil located in these areas of the project site may be lost in severe storms or 100-year flood events.

The project also includes components that aim to reduce runoff and maintain water quality during operation. The project site would be developed with two river impoundment structures, modifications to the existing Santa Ana River embankment slopes, walkways and other paved areas, and landscaping. The two river impoundments would create two ponded water surface areas totaling approximately 38 acres that would allow for year-round infiltration of stormwater and infiltration of purified water during operation. The project would require modifications to the existing turnout structure, allowing to discharge into either the pipeline leading to the south impoundment pump station or directly into the river. This would supply ultra-pure Groundwater Replenishment System water to the impoundments.

During dry weather operation, the impoundment water levels would be maintained using groundwater replenishment system (GWRS) water supplied by OCWD. To address impoundment water quality concerns, dry weather nuisance flows in all adjacent tributary storm drain lines would be captured/diverted by gravity. These nuisance flows would be pumped to Orange County Sanitation District sewer lines and treatment facilities, with a few storm drain lines on the east side of the project discharged to the river channel downstream of the lower impoundment. This would minimize the possibility of any dry weather flows reaching the impoundments and mixing with GWRS water. In this operational condition, the impoundments would be filled to within 6 to 12 inches of the impoundment overflow elevation and maintained with the ability to bypass a portion of the water through a bypass structure containing a modulating weir so water levels and discharge flow can be controlled.

Section 4.4: Geology and Soils
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A low flow event is defined as a precipitation event that produces expected flow volumes at the project site of less than 200 acre-feet (the volume of water retained by the two impoundments).

During a rain event, the dry weather nuisance diversion systems are turned off, allowing flow from the tributaries to enter the river. Flows to the project site would consist of a combination of flows from the surrounding tributaries and from Prado Dam releases. Generally, in low flow conditions the GWRS water supply to the impoundments would be halted, and the GWRS water would be allowed to infiltrate or may be pumped to Burris Basin, an off-river basin operated by OCWD. Santa Ana River flows, either tributary or from Prado Dam, would fill the impoundments up to the 200-acrefoot capacity. In any event where flows over the rubber dam reach a 6-inch nappe (approximately 320 cfs), the inflatable dams would be deflated.

High flow events are defined as events where the flows reaching the project site, which include tributary runoff and flows from Prado Dam, are 200 acre-feet or greater. In these conditions, both impoundments would be evacuated, and the rubber dams would be deflated to allow complete storm conveyance in the Santa Ana River channel. For this operation, GWRS inflows to the impoundments would be halted and allowed to fully infiltrate, which takes approximately 10 days, or the GWRS water would be drained and pumped to Burris Basin, which is anticipated to take approximately 3 days. The impoundments would then be fully deflated to maintain peak flood capacity of the Santa Ana River channel. In the later parts of the storm, the rubber dams would be reinflated with the intent of capturing the full operation volume, or 200 acre-feet, in both impoundments. During any event, regardless of expected volume, when the flow exceeds 320 cfs (6-inch nappe) over the dams, they would automatically deflate as a safety mechanism to prevent damage. There would be no changes to other segments of the Santa Ana River. Therefore, the impoundments would not result in additional erosion or siltation impact compared to the existing conditions.

The existing levee embankment within the project site consists of riprap-lined riverbank. The riverbank protection is comprised of loose and grouted riprap at a 2(H):1(V) slope. The project would modify the existing riprap with soil cement bank protection, reinforced concrete terraces and steps and new riprap, therefore, no erosion and siltation would occur during operation. Also, once constructed, surface drainage in the project site would primarily remain the same, with the river trails and surrounding areas draining to the Santa Ana River. The trail and trail improvement design would include various impervious surface materials and landscaping, and there would be no exposed soils with risk of substantial soil erosion or siltation. Additionally, a water quality management plan will be developed to address the required water quality components of the project elements. The project would be designed to comply with the North Orange County TGD and Model water quality management plan to achieve MS4 permit compliance.

Therefore, operational impacts related to substantial soil erosion or loss of topsoil would be less than significant.

Section 4.4: Geology and Soils
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Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.4.4.6 Threshold GEO-3: Geologic Stability
Impact Analysis
Unstable soils impact related to on- or off-site landslide is addressed under Threshold GEO-1.iv and liquefaction or collapse is addressed under Threshold GEO-1iii. The following discussion of the potential for lateral spreading and subsidence is summarized from the Preliminary Geotechnical Evaluation, as applicable (Appendix F).

Lateral Spreading
The project site is located within the free-faces of the Santa Ana River; therefore, there is a potential for seismically induced lateral spread. Lateral spreading is directly associated with areas of liquefaction, which is discussed in Threshold GEO-1.iv. As discussed under Threshold GEO1.iv, similar to impacts from liquefaction, impacts from lateral spreading would be reduced to a less than significant level with the required compliance with the recommendations contained in the Preliminary Geotechnical Evaluation and requirements of the appropriate governing jurisdictions and applicable building codes that would be considered during the structural design and construction of the project. Impacts would be less than significant.

Subsidence
The City of Anaheim Local Hazard Mitigation Plan (2022) and the City of Orange Local Hazard Mitigation Plan (2016) do not identify subsidence as a hazard of concern for either city.

Additionally, the project would be designed and constructed by adhering to the site-specific recommendations contained in the Preliminary Geotechnical Evaluation and requirements of the appropriate governing jurisdictions and applicable building codes that would be considered during the structural design and construction of the project. Therefore, impacts from subsidence would be less than significant.

Slope Stability
The project involves embankment improvements that required a slope stability analysis to evaluate the stability of the proposed embankment slopes based on the north impoundment area. The slope stability evaluation determined that while the proposed embankment slopes with a slope ratio of 2:1 (horizontal to vertical) would have adequate slope stability, the embankment slopes placed at a slope ratio of 1.5:1 (horizontal to vertical) may not result in adequate slope stability under certain scenarios.

The slope stability analysis indicated that by removing the outer portion of the slope and replacing with a stabilization fill slope with an approximately 15-foot-wide soil cement zone, the slope stability safety level would increase to adequate levels. The project would be designed and constructed in Section 4.4: Geology and Soils
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compliance with the CBC standards and recommendations contained in the Geotech investigation to be reviewed and approved by the applicable governing entities. (PPP GEO-1). Therefore, the project would not be impacted by slope instability to result in adverse environmental impacts.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.4.4.7 Threshold GEO-4: Expansive Soils
Impact Analysis
The project site’s expansion index has not been tested. However, the Preliminary Geotechnical Evaluation (Appendix F) included results from previous geotechnical evaluations in the nearby area, which identified an expansion index of “0.” Also, the Preliminary Geotechnical Evaluation concluded that the on-site soils are generally suitable for use as embankment fill and trench backfill as long as they are free of trash, debris, roots, vegetation, deleterious materials, and contamination.

Therefore, it is anticipated that expansion potential for on-site soils is minimal, and impacts would be less than significant.

Level of Significance Before Mitigation: Less than significant.

Mitigation Measures: No mitigation measures are required.

4.4.5 Cumulative Impacts
This section addresses various potential cumulative impacts relating to geology and soils that could result from implementation of the project.

Geology and soil-related impacts are generally site-specific and are determined by on-site soil characteristics, proximity to faults, topography, and proposed land uses. Development projects are analyzed on an individual basis and must comply with established requirements of the applicable jurisdiction’s development standards and the CBC as they pertain to protection against known geologic hazards and potential geologic and soil-related impacts.

4.4.5.1 Cumulative Threshold GEO-1.i Through GEO-1.iv: Exposure to SeismicRelated Hazards Cumulative effects related to geology resulting from the implementation of the project as well as surrounding areas could expose more people and property to potential impacts due to seismic activity. Long-term impacts related to geology include the exposure of people to the potential for seismically induced ground shaking and seismic-related ground failure. Implementation of other cumulative projects would incrementally increase the number of people and structures subject to a seismic event. Seismic and geologic significance is considered on a project-by-project basis through Section 4.4: Geology and Soils
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the preparation of design-level geotechnical studies and implementation of recommendations contained therein. The potential for any project to be affected by or any project to exacerbate an existing geotechnical hazard would be reduced to a less than significant level through strict engineering guidelines as they pertain to protection against known geologic hazards and potential geologic and soil-related impacts such as rupture of a known earthquake, ground shaking, liquefaction, and landslide. Therefore, cumulative impacts related to seismic-related hazards, would be less than significant.

4.4.5.2 Cumulative Threshold GEO-2: Soil Erosion or Topsoil Loss With respect to erosion, as discussed under Threshold GEO-2, regulatory requirements mandate that the project incorporate BMPs during construction and long-term operation to ensure that significant erosion impacts do not occur. Other development projects in the vicinity of the project would be required to comply with the same regulatory requirements as the project to reduce substantial adverse water and wind erosion impacts. Because the project and other cumulative projects would be subject to similar mandatory regulatory requirements to control erosion hazards during construction and long-term operation, the project would not result in a cumulatively considerable contribution to a significant cumulative impact related to erosion.

4.4.5.3 Cumulative Threshold GEO-3: Geologic Stability and Threshold GEO-4:

Expansive Soils
Development of the project as well as other cumulative projects in the surrounding areas would be required to be constructed in accordance with the latest edition of the CBC and to adhere to all current earthquake construction standards, including those relating to soil characteristics set forth by the City. Therefore, no elements of the project would contribute to any cumulatively considerable geologic and soils impacts.

4.4.6 Level of Significance Before Mitigation
Upon implementation of the plans, programs, and policies, the following threshold would be less than significant:
• Threshold GEO-1i:Implementation of the project would not cause a substantial adverse impact involving rupture of a known earthquake fault.
• Threshold GEO-1ii: Implementation of the project would not cause substantial adverse impact involving strong seismic ground shaking.
• Threshold GEO-1iii: Implementation of the project would not cause substantial adverse impact involving liquefaction.
• Threshold GEO-1iv: Implementation of the project would not cause substantial adverse impact involving landslide.

Section 4.4: Geology and Soils
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• Threshold GEO-2: Implementation of the project would not cause a substantial adverse impact involving soil erosion or the loss of topsoil.
• Threshold GEO-3: Implementation of the project would not result in adverse impacts related to unstable geologic units or soils.
• Threshold GEO-4: Implementation of the project would not result in adverse impacts related to expansive soil.

4.4.7 Mitigation Measures
No mitigation measures are required.

4.4.8 Level of Significance After Mitigation
Not applicable.

Section 4.5: Greenhouse Gas Emissions
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4.5 Greenhouse Gas Emissions
This section evaluates the potential for impacts relating to greenhouse gas (GHG) emissions resulting from implementation of the OC River Walk Project (project).

4.5.1 Environmental Setting

4.5.1.1 Regulatory Setting
This section describes the federal, state, and local regulatory framework adopted to address GHG emissions.

Federal
U.S. Environmental Protection Agency
The U.S. Environmental Agency (USEPA) is responsible for implementing federal policy to address global climate change. In 2009, the USEPA issued a Final Rule for mandatory reporting of GHG emissions, which applies to fossil fuel and industrial gas suppliers, direct GHG emitters, and manufacturers of heavy-duty and off-road vehicles and requires annual emissions reporting.

This rule does not regulate the emission of GHGs; it only requires the monitoring and reporting of GHG emissions for those sources above certain thresholds.

State
Executive Order S-3-05
On June 1, 2005, California’s Governor announced, through Executive Order (EO) S-3-05, the following GHG emissions reduction targets:
• By 2010, California shall reduce GHG emissions to 2000 levels. • By 2020, California shall reduce GHG emissions to 1990 levels. • By 2050, California shall reduce GHG emissions to 80 percent below 1990 levels.

EO S-3-05 directed the Secretary of the California Environmental Protection Agency to coordinate efforts to meet the targets with the heads of other state agencies (the Secretary of the California Business, Transportation and Housing Agency; Secretary of the California Department of Food and Agriculture; Secretary of the California Resources Agency; Chairperson of the California Air Resources Board (CARB); Chairperson of the California Energy Commission; and the President of the California Public Utilities Commission). This group became the California Climate Action Team. In 2006, the state Legislature passed the California Global Warming Solutions Act of 2006 (Assembly Bill [AB] 32), which created a comprehensive, multiyear program to reduce GHG emissions in California, as described below. In 2016, the state Legislature passed Senate Bill (SB) 32, which codifies a 2030 GHG emissions reduction target of 40 percent below 1990 levels.

Section 4.5: Greenhouse Gas Emissions
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Assembly Bill 32, the California Global Warming Solutions Act of 2006 In September 2006, the state Legislature adopted AB 32, the California Global Warming Solutions Act of 2006. AB 32 focuses on reducing GHG emissions in California. GHGs as defined under AB 32 include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride (SF6). Under AB 32, CARB has the primary responsibility for reducing GHG emissions and continues with the Climate Change Action Team to coordinate statewide efforts and promote strategies that can be undertaken by many other California agencies. AB 32 required CARB to adopt rules and regulations that would achieve GHG emissions equal to statewide levels in 1990 by 2020.

In general, AB 32 directed CARB to do the following:
• Prepare and approve a Scoping Plan for achieving the maximum technologically feasible and cost-effective reductions in GHG emissions from sources or categories of sources of GHGs by 2020 and update the Scoping Plan every 5 years • Maintain and continue reductions in emissions of GHG beyond 2020 • Identify the statewide level of GHG emissions in 1990 to serve as the emissions limit to be achieved by 2020
• Identify and adopt regulations for discrete early actions that could be enforceable on or before January 1, 2010
• Adopt a regulation that establishes a system of market-based declining annual aggregate emission limits for sources or categories of sources that emit GHG emissions • Convene an Environmental Justice Advisory Committee to advise CARB in developing and updating the Scoping Plan and any other pertinent matter in implementing AB 32 • Appoint an Economic and Technology Advancement Advisory Committee to provide recommendations for technologies, research, and GHG emissions reduction measures Regarding the first bulleted item above, the most recent update to the Scoping Plan, the 2022 Scoping Plan, was adopted by CARB in December 2022. The 2022 Scoping Plan assesses progress toward the statutory 2030 target and identifies a path to achieving carbon neutrality by 2045 (CARB 2022).

Senate Bill 32
Effective January 1, 2017, SB 32 (Stats. 2016, Ch. 249) added a new Section 38566 to the California Health and Safety Code. It directs CARB to ensure that statewide GHG emissions are reduced to at least 40 percent below the statewide GHG emissions limit (levels than occurred in 1990) no later than December 31, 2030.

Assembly Bill 1279
AB 1279, the California Climate Crisis Act, enacted in September 2022, updates the goals of AB

32. The bill established a statewide goal to achieve net-zero GHG emissions by 2045 and achieve Section 4.5: Greenhouse Gas Emissions
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and maintain net-negative GHG emissions thereafter. Additionally, the bill established a specific target for statewide anthropogenic GHG emissions to be reduced to at least 85 percent below the 1990 levels by 2045. The bill requires CARB to work with relevant state agencies to ensure that updates to the Scoping Plan identify and recommend measures to achieve these policy goals and to identify and implement a variety of policies and strategies that enable CO2 removal solutions and carbon capture, utilization, and storage technologies in California, as specified. The bill also requires CARB to submit an annual progress report.

Senate Bill 375: Sustainable Communities Strategy
SB 375 was adopted in 2008 and provides a new planning process that coordinates land use planning, Regional Transportation Plans, and funding priorities to help California meet the GHG reduction goals established in AB 32. SB 375 requires Regional Transportation Plans, developed by Metropolitan Planning Organizations, to incorporate a Sustainable Communities Strategy in their Regional Transportation Plans. The goal of the Sustainable Communities Strategy is to reduce regional vehicle miles traveled through land use planning and consequent transportation patterns.

SB 375 also includes provisions for streamlined California Environmental Quality Act (CEQA) review for some infill projects, such as transit-oriented development.

Regional
South Coast Air Quality Management District
The South Coast Air Quality Management District (SCAQMD) has been evaluating GHG significance thresholds since April 2008. On December 5, 2008, the SCAQMD Governing Board adopted an interim GHG significance threshold of 10,000 metric tons carbon dioxide equivalent (MTCO2e) for stationary sources, rules, and plans where the SCAQMD is lead agency (SCAQMD permit threshold). For non-industrial development, the interim thresholds establish a screening level of 3,000 MTCO2e for annual emissions. The screening level is intended to capture 90 percent of GHG emissions from new development projects in the residential/commercial sectors. Additionally, construction emissions are to be amortized over the life of the project, defined as 30 years.

SCAQMD is not the lead agency for the project. However, in the absence of other thresholds of significance promulgated by the SCAQMD, and because the City of Anaheim nor City of Orange do not presently have their own thresholds of significance, the Cities have been using the SCAQMD’s 3,000 MTCO2e threshold for non-industrial projects. This approach is consistent with CEQA Guidelines, Section 15064.7(b), which states that “a lead agency may consider thresholds of significance previously adopted or recommended by other public agencies or recommended by experts, provided the decision of the lead agency to adopt such thresholds is supported by substantial evidence.” The SCAQMD is the regional authority on air emissions and has published documentation for threshold development (SCAQMD 2008). Although the AB 32 target of reducing statewide emissions to 1990 levels by 2020 was the primary state goal at the time of Section 4.5: Greenhouse Gas Emissions
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SCAQMD threshold development, SCAQMD also determined that the interim thresholds would contribute to achieving the Executive Order S-3-05 goal of reducing emissions to 80 percent below 1990 levels by 2050. SB 32 adopted an interim threshold of 40 percent reduction from 1990 levels by 2030 to put the state on track to achieve the S-3-05 2050 target. The EO S-3-05 target has been superseded by the AB 1279 goal of an 85 percent reduction in anthropogenic emissions from 1990 levels by 2045. However, the 2022 Scoping Plan states that the SB 32 2030 reduction target remains a critical step to achieving the AB 1279 target. Additionally, the Scoping Plan acknowledges that new technologies and statewide policies would be required to achieve the AB 1279 target beyond 2030, such as increased emissions reduction standards and increased use of zero-emissions vehicles. As such, a goal of 85 percent reduction from 1990 levels or net-zero GHG emissions is not prescribed as a local target or threshold. The 2030 interim target remains an appropriate threshold for local agencies to achieve a fair share reduction toward statewide emissions reduction goals. As such, the City of Anaheim and other lead agencies throughout the basin continue to apply the SCAQMD interim thresholds.

Connect SoCal 2024
On April 4, 2024, the Southern California Association of Government (SCAG) Regional Council adopted the Connect SoCal 2024–2050 Regional Transportation Plan/ Sustainable Communities Strategy project (SCAG 2024). Connect SoCal 2024 charts a course for closely integrating land use and transportation so that the region can grow smartly and sustainably. The SCAG region must achieve specific federal air quality standards and is required by state law to lower regional GHG emissions (SCAG 2024). Connect SoCal 2024 transportation projects include highway improvements, railroad grade separations, bicycle lanes, new transit hubs and replacement bridges.

Providing new active transportation facilities is identified as a critical component of the plan.

Local
City of Anaheim General Plan
The City of Anaheim General Plan’s Circulation Element and Green Element, adopted in 2004, contain goals that focus on the reduction of vehicle trips and vehicle emissions (City of Anaheim 2004). Goals and policies from the Circulation Element and Green Elements related to air quality that are applicable to the project are listed below:

Circulation Element
• Goal 8.1: Encourage Pedestrian Travel
- Policy 8.1-1. Encourage and improve pedestrian facilities that link development to the circulation network and that serve as a transition between other modes of travel. - Policy 8.1-2. Improve pedestrian and bicycle connections from residential neighborhoods to retail activity centers, employment centers, schools, parks, open space areas and community centers.

Section 4.5: Greenhouse Gas Emissions
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- Policy 8.1-3. Encourage barrier free accessibility for all handicapped residents, employees and visitors throughout the City’s circulation system. - Policy 8.1-4. Support the planning of sidewalks of appropriate width to allow the provision of buffers to shield non-motorized traffic from vehicles. - Policy 8.1-5. Add raised, landscaped medians and bulbouts, where appropriate, to reduce exposure to cross traffic at street crossings. - Policy 8.1-6. When appropriate, walkways should include pedestrian amenities such as shade trees and/or plantings, trash bins, benches, shelters, and directional kiosks.
- Policy 8.1-7. Ensure that streets and intersections are designed to provide visibility and safety for pedestrians.
- Policy 8.1-8. Improve pedestrian amenities adjacent to Metrolink and Amtrak stations.
- Policy 8.1-9. Enhance and encourage pedestrian amenities and recreation, retail and employment opportunities in mixed-use areas to enhance non-motorized transportation.
- Policy 8.1-10. Require commercial developments to provide specific pedestrian access points independent from auto entrances.
- Policy 8.1-11. Coordinate with appropriate agencies to ensure that transit stops are accessible to pedestrians.

Green Element
• Goal 8.1: Reduce locally generated emissions through improved traffic flows and construction management practices.
- Policy 8.1-1. Reduce vehicle emissions through traffic flow improvements, such as traffic signal synchronization, Intelligent Transportation Systems, the Scoot Adaptive Traffic Control System, and related capital improvements. - Policy 8.1-2. Regulate construction practices, including grading, dust suppression, chemical management, and encourage pre-determined construction routes that minimize dust and particulate matter pollution. • Goal 9.1: Reduce single-occupancy vehicle trips.
- Policy 9.1-2. Encourage development of new commercial and industrial projects that provide on-site amenities that help to lesson vehicle trips such as on-site day care facilities, cafeterias, automated teller machines and bicycle storage facilities. - Policy 9.1-3. Encourage use of vanpools and carpools by providing priority parking through the project design process.
- Policy 9.1-4. Encourage bicycle and pedestrian travel by improving the City’s trail and bikeway master plan and by providing convenient links between the trail system and desired destinations.

Section 4.5: Greenhouse Gas Emissions
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Anaheim Public Utilities Greenhouse Gas Reduction Plan
The Anaheim Public Utilities’ (APU) Greenhouse Gas Reduction Plan (GHG Plan) outlines the utility's vision for developing sustainable and environmentally friendly electric and water resources while maintaining affordability and reliability for customers. Created in 2015 and updated in 2020, the plan establishes baseline metrics, tracks progress, and sets new targets for 2030 and 2045, aligning with California's goal of 100 percent clean energy by 2045. The plan focuses on reducing greenhouse gas emissions through various initiatives including renewable power transition, energy efficiency, water conservation, and electric transportation, while incorporating community feedback and designing programs specifically for Anaheim’s needs.

City of Orange General Plan Natural Resources Element
The City of Orange General Plan Natural Resources Element, adopted in 2010, contains goals that focus on the reduction of GHG emissions (City of Orange 2010a). Relevant goals and policies are listed below:
• Goal 2.0: Protect air, water, and energy resources from pollution and overuse. - Policy 2.2. Support alternative transportation modes, alternative technologies, and bicycle- and pedestrian-friendly neighborhoods to reduce emissions related to vehicular travel.
- Policy 2.10. Work toward replacing existing City vehicles with ultra-low or zero emission vehicles. At a minimum, new City vehicles shall be low emission vehicles as defined by the California Air Resources Board, except if certain vehicle types are not available in the marketplace. Public safety vehicles are exempted from this requirement.
• Goal 3.0: Prepare for and adapt to the effects of climate change and promote practices that decrease the City’s contribution to climate change. - Policy 3.1. Evaluate the potential effects of climate change on the City’s human and natural systems and prepare strategies that allow the City to appropriately respond and adapt.
- Policy 3.2. Develop and adopt a comprehensive strategy to reduce greenhouse gasses (GHGs) within Orange by at least 15 percent from current levels by 2020.

4.5.1.2 Existing Conditions
Global Climate Change Overview
Climate change refers to any substantial change in measures of climate (such as temperature, precipitation, or wind) lasting for decades or longer. According to the USEPA, Earth’s climate has changed many times during the planet’s history, including events ranging from ice ages to long periods of warmth. Historically, natural factors such as volcanic eruptions, changes in Earth’s orbit, and the amount of energy released from the sun have affected Earth’s climate. Some GHGs, Section 4.5: Greenhouse Gas Emissions
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such as water vapor, occur naturally and are emitted to the atmosphere through natural processes, while others are emitted through human activities. Since the late 18th century, human activities associated with the Industrial Revolution have changed the composition of the atmosphere and, therefore, are very likely influencing Earth’s climate. For more than 200 years, the burning of fossil fuels, such as coal and oil, and deforestation have caused concentrations of heat-trapping GHG to increase substantially in the atmosphere.

The accumulation of GHGs in the atmosphere regulates Earth’s temperature. Without it, the temperature of Earth would be about zero degrees Fahrenheit (°F) instead of its current 57°F (NOAA 2023). Global climate change concerns focus on if human activities are leading to an enhancement of the greenhouse effect.

Greenhouse Gases
GHGs include but are not limited to CO2, CH4, N2O, ozone (O3), water vapor, fluorinated gases (hydrofluorocarbons, perfluorocarbons, SF6, and nitrogen trifluoride [NF3]), chlorofluorocarbons, and hydrochlorofluorocarbons. Some GHGs, such as CO2, CH4, and N2O, occur naturally and are emitted into the atmosphere through natural processes and human activities. Of these gases, CO2 and CH4 are emitted in the greatest quantities from human activities. Manufactured GHGs, which have a much greater heat-absorption potential than CO2, include fluorinated gases, such as hydrofluorocarbons, perfluorocarbons, and SF6, which are associated with certain industrial products and processes.

CO2 enters the atmosphere through the burning of fossil fuels, solid waste, trees, and wood products and other chemical reactions, such as those that occur in cement manufacturing. Globally, the largest source of anthropogenic CO2 emissions is the combustion of fossil fuels in power plants, automobiles, industrial facilities, and other similar sources. CH4 is emitted from a variety of both natural and humanrelated sources, including fossil fuel production, animal husbandry, and waste management. N2O is emitted during agricultural and industrial activities, during combustion of fossil fuels and solid waste, and wastewater treatment (USEPA 2025). Hydrofluorocarbons, perfluorocarbons, and SF6 are synthetic, powerful GHGs emitted from a variety of industrial processes and the production of chlorodifluoromethane. Construction and operation of the project would not include any industrial processes, and chlorodifluoromethane has been mostly phased out of use in the United States (USEPA 2025); therefore, these GHGs are not discussed further in this analysis.

Individual GHGs have varying heat-trapping properties and atmospheric lifetimes. The CO2e is a consistent methodology for comparing GHG emissions because it normalizes various GHG emissions to a consistent measure based on their global warming potential. Each GHG is compared to CO2 with respect to its ability to trap infrared radiation, its atmospheric lifetime, and its chemical structure. For example, the global warming potential for CH4 is 25 (which means that emissions of 1 metric ton of CH4 are equal to emissions of 25 MTCO2e) and for N2O is 298 (CAPCOA 2022).

Section 4.5: Greenhouse Gas Emissions
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Greenhouse Gas Emissions Inventories
To evaluate and reduce the potential adverse impact of climate change, federal, state, and local organizations conducted GHG inventories to estimate levels of and trends in GHG emissions and removals. The following summarizes these GHG inventories.

Federal
In 2022, the United States emitted approximately 6.3 billion MTCO2e. Total U.S. emissions in 2022 decreased by 17 percent from 2005 levels, and emissions increased from 2021 to 2022 by one percent. The increase in GHG emissions was largely attributable to an increase in fossil fuel combustion. This increase in fossil fuel consumption emissions was from increased energy use, due in part to the continued rebound in economic activity after the height of the COVID-19 pandemic (USEPA 2024).

State of California Emissions
CARB is responsible for developing the state GHG emission inventory. This inventory estimates the amount of GHGs emitted to and removed from the atmosphere by human activities in the state and supports the AB 32 Climate Change Program. CARB’s current GHG emission inventory covers the years 2000–2022 and is based on fuel use, equipment activity, industrial processes, and other relevant data (e.g., housing, landfill activity, and agricultural lands).

According to CARB emission inventory estimates, the state emitted approximately 371.1 million MTCO2e emissions in 2022. This is a decrease of 9.3 million MTCO2e from 2021. The 2022 emissions data shows that the state is continuing its established long-term trend of GHG emissions declines, despite the anomalous emissions trends from 2019 through 2021, due in large part to the impacts of the COVID-19 pandemic. CARB estimates that transportation was the source of approximately 39 percent of the state’s GHG emissions in 2022, followed by industrial sources at 23 percent and electricity generation at 11 percent. The largest emissions category in the transportation sector is On-Road Transportation, which consists of passenger vehicles (cars, motorcycles, and light-duty trucks) and heavy-duty vehicles. The remaining sources of GHG emissions were residential activities at 8 percent, commercial activities at 6 percent, agriculture at 8 percent, and electricity imports at 5 percent (CARB 2024).

Regional
The City of Anaheim prepared a community emissions inventory as part the Program Environmental Impact Report for the City of Anaheim General Plan Focused Update. Community emissions for Year 2021 were calculated to be 4,030,359 MTCO2e (City of Anaheim 2024).

Similarly, the Program Environmental Impact Report prepared for the City of Orange General Plan included an inventory of GHG emissions in the City of Orange. Year 2004 emissions were calculated to be 2,072,493 MTCO2e, and were forecast to reach 3,159,568 in 2030 (City of Orange Section 4.5: Greenhouse Gas Emissions
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2010b). Additionally, SCAG prepared an inventory of transportation emissions in the SCAG region, including Orange County, for the Program Environmental Impact Report prepared for the Connect SoCal 2024. In 2019, total transportation emissions for the SCAG region were calculated to be 66.42 million MTCO2e (SCAG 2024).

4.5.2 Thresholds of Significance
According to Appendix G of the CEQA Guidelines, the project would have a significant impact on GHG emissions if it would:
• Threshold GHG-1: Generate greenhouse gas emissions, either directly or indirectly, that may have a significant impact on the environment.
• Threshold GHG-2: Conflict with an applicable plan, policy or regulation adopted for the purpose of reducing the emissions of greenhouse gases.

The Initial Study (Appendix A to this Environmental Impact Report [EIR]) determined that the following thresholds would have less than significant or no impact, and these environmental topics will not be addressed further in this section of the Draft EIR:
• Threshold GHG-1 (operation impact only)
• Threshold GHG-2

4.5.3 Plans, Programs, and Policies
This section addresses plans, programs, and policies relevant to the project.

PPP GHG-1 Materials generated from construction of the project will be recycled as required by the California Green Building Codes and Cities of Anaheim and Orange, which require 65 percent of all debris to be diverted from the landfill.

4.5.4 Environmental Impacts
The following sections address various potential impacts relating to GHG emissions that could result from implementation of the project.

4.5.4.1 Threshold GHG-1: Generation of Greenhouse Gas Emissions (Construction)
Impact Analysis
As described in Section 4.5.1.1, Regulatory Setting, under South Coast Air Quality Management District, the significance of project GHG emissions is determined based on the SCAQMD screening threshold of 3,000 MTCO2e per year for non-industrial uses. Project GHG emissions are quantified for the construction effort and amortized over a 30-year project lifetime. Project construction would result in GHG emissions from use of fossil fuels for construction equipment, Section 4.5: Greenhouse Gas Emissions
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haul trucks, and worker vehicle trips. Construction emissions were modeled for the project using CalEEMod Version 2022.1.1.29 based on assumptions consistent with the air quality modeling outlined in Section 4.1, Air Quality. Refer to Appendix C, Air Quality/GHG Data, of the Draft EIR for detailed modeling input and output.

Anaheim City CouncilDecember 9, 2025

Anaheim City Council
December 9, 2025