HomeMy WebLinkAbout2026-06-09; City Council; Resolution 2026-114Exhibit 1 RESOLUTION NO. 2026-114
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CARLSBAD,
CALIFORNIA, ACCEPTING THE WILDFIRE MITIGATION PLAN PHASE 1 REPORT
AND AUTHORIZING THE CITY MANAGER TO INITIATE PHASE 2, INCLUDING
DEVELOPING A COMMUNITY WILDFIRE PROTECTION PLAN, AND TO
INCLUDE FUNDING FOR COMMUNITY OUTREACH AND FOR THE
CONVERSION OF A PART-TIME FIRE PREVENTION SPECIALIST TO A FULL-
TIME ASSISTANT FIRE MARSHAL POSITION IN THE FY 2026-27 BUDGET TO
BE CONSIDERED BY THE CITY COUNCIL FOR ADOPTION ON JUNE 16, 2026
WHEREAS, the City Council authorized funding on February 25, 2025, for the development of a
comprehensive Wildfire Mitigation Plan to address increasing wildfire risk within the City of Carlsbad;
and
WHEREAS, the Wildfire Mitigation Plan is a proactive, two-phase framework designed to guide
city policy, investment and wildfire risk-reduction strategies; and
WHEREAS, Phase 1 of the Wildfire Mitigation Plan, consisting of a Wildfire Hazard and Risk
Assessment, has been completed and provides a comprehensive evaluation of wildfire hazards, fire
behavior, structural vulnerability, defensible space conditions, operational constraints, and mitigation
opportunities throughout the city; and
WHEREAS, the Phase 1 assessment identified increased wildfire risk associated with expanded
California Department of Forestry and Fire Protection (CAL FIRE) state fire hazard severity zone
designations, the city's wildland-urban interface, evolving regulatory requirements, and limitations on
vegetation management activities within environmentally sensitive areas and further identified
numerous recommendations to reduce wildfire risk, including expanded vegetation management,
defensible space programs, community outreach and education, fuel modification oversight, wildfire
planning efforts, and additional staffing resources; and
WHEREAS, Phase 2 of the Wildfire Mitigation Plan will include development of a Community
Wildfire Protection Plan through collaboration with residents, community stakeholders, regulatory
agencies, land managers, and city staff to identify and prioritize wildfire mitigation strategies and
implementation actions; and
WHEREAS, the City Council finds that advancement to Phase 2 is necessary to develop a
community-informed framework for reducing wildfire risk, enhancing community resilience, and
protecting life, property, and natural resources; and
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WHEREAS, the Phase 1 assessment identified the need for additional staffing resources to
support wildfire mitigation planning and implementation, defensible space and fuel modification
inspection programs, vegetation management planning, public outreach and education, and
compliance with evolving state wildfire regulations; and
WHEREAS, staff recommends converting an existing part-time Fire Prevention Specialist
position to a full-time Assistant Fire Marshal position to oversee Phase 2 of the Wildfire Mitigation Plan,
including development of a Community Wildfire Protection Plan and associated stakeholder
engagement, planning, environmental review, and project development activities.
NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Carlsbad, California, as
follows:
1.That the above recitations are true and correct.
2. That the proposed action is not a “project” as defined by California Environmental
Quality Act, or CEQA, Section 21065 and does not require environmental review under
CEQA Guidelines Section 15060(c)(3) and 15061(b)(3). Any subsequent action or
direction stemming from the proposed action may require the preparation of an
environmental document in accordance with existing local, state, and federal
regulations, including CEQA and the implementing guidelines.
3.That the City Council accepts the Wildfire Mitigation Plan Phase 1 Report (Attachment
A).
4. That the City Council authorizes the City Manager, or designee, to initiate Phase 2 of the
Wildfire Mitigation Plan, including development of a Community Wildfire Protection
Plan and associated stakeholder engagement, planning, environmental review, and
project development activities.
5.That the City Council further authorizes the City Manager to include funding for
community outreach and for the conversion of a part-time Fire Prevention Specialist to
a full-time Assistant Fire Marshal position in the FY 2026-27 budget to be considered by
the City Council for adoption on June 16, 2026.
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PASSED, APPROVED AND ADOPTED at a Regular Meeting of the City Council of the City
of Carlsbad on the 9th day of June, 2026, by the following vote, to wit:
AYES: Blackburn, Bhat-Patel, Acosta, Burkholder, Shin.
NAYS: None.
ABSTAIN: None.
ABSENT: None.
______________________________________
KEITH BLACKBURN, Mayor
______________________________________
SHERRY FREISINGER, City Clerk
(SEAL)
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Wildfire Mitigation Plan Phase 1: Wildfire
Hazard and Risk Assessment
City of Carlsbad
MAY 2026
Prepared for:
CITY OF CARLSBAD FIRE DEPARTMENT
2560 Orion Way
Carlsbad, California 92010
Contact: Darcy Davidson
Prepared by:
687 S Coast Highway 101,
Encinitas, California 92024
Contact: Matthew Crockett
Attachment A
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Table of Contents
SECTION PAGE NO.
Executive Summary ........................................................................................................................................................... v
1 Introduction .......................................................................................................................................................... 1
1.1 Purpose and Intent ................................................................................................................................. 1
1.2 Wildfire Hazard and Risk Assessment Goals and Objectives .............................................................. 2
1.3 Wildfire Hazard and Risk Assessment Planning Process ..................................................................... 2
2 Plan Area Description .......................................................................................................................................... 3
2.1 Location .................................................................................................................................................. 3
2.2 Land Ownership and Land Use .............................................................................................................. 3
2.3 Fire Protection ........................................................................................................................................ 7
2.3.1 City of Carlsbad Fire Department ............................................................................................. 7
2.3.2 Fire Protection Partnerships .................................................................................................... 8
2.4 Existing Fire Risk Reduction Programs ................................................................................................. 8
2.4.1 Fire Codes and Ordinances ...................................................................................................... 8
2.4.2 Habitat Management Plan ....................................................................................................... 9
2.4.3 Fuel Modification Zone Requirements ................................................................................. 14
2.4.4 Annual Hazard Reduction/Weed Abatement Program ........................................................ 15
2.4.5 Defensible Space Inspections ............................................................................................... 15
2.4.6 Annual Fire Inspection Program ............................................................................................ 16
2.4.7 Community Education and Engagement .............................................................................. 16
2.4.8 Countywide Chipping Events ................................................................................................. 17
2.5 Fire Hazard Areas ................................................................................................................................ 18
2.5.1 State Fire Hazard Severity Zones .......................................................................................... 18
2.5.2 Carlsbad Fire Suppression Zone ........................................................................................... 19
3 Wildfire Environment ........................................................................................................................................ 23
3.1 Climate ................................................................................................................................................. 23
3.2 Terrain .................................................................................................................................................. 24
3.3 Vegetation and Fuels .......................................................................................................................... 25
3.3.1 Vegetative Fire Hazard .......................................................................................................... 25
3.3.2 Vegetation Management to Mitigate Wildfire Hazard and Risk .......................................... 36
3.4 Wildfire Types and Potential Fire Behavior ........................................................................................ 39
3.4.1 Wildfire History ....................................................................................................................... 41
4 Values at Risk .................................................................................................................................................... 45
4.1 Wildland-Urban Interface .................................................................................................................... 45
4.2 Life Safety ............................................................................................................................................ 46
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4.2.1 Structures and Population .................................................................................................... 46
4.3 Critical Facilities Infrastructure ........................................................................................................... 48
4.4 Natural Resources ............................................................................................................................... 49
5 Wildfire Hazard and Risk Assessment Methods ............................................................................................. 55
5.1 Plan and Data Evaluation ................................................................................................................... 55
5.2 Field Assessment ................................................................................................................................ 55
5.3 Wildfire Hazard Modeling .................................................................................................................... 55
5.3.1 Flame Length ......................................................................................................................... 56
5.3.2 Burn Probability ...................................................................................................................... 57
5.3.3 Relative Wildfire Hazard ........................................................................................................ 58
5.4 Wildfire Progression Modeling ............................................................................................................ 58
5.5 Wildfire Mitigation Priority Assessment.............................................................................................. 59
5.6 Critical Facilities Wildfire Exposure Assessment ............................................................................... 60
5.7 Evacuation Routes and Traffic Calming Devices ............................................................................... 61
5.8 Tree Hazard Assessment .................................................................................................................... 61
5.8.1 Hazardous Tree Conditions ................................................................................................... 61
5.8.2 Evaluation Methods ............................................................................................................... 63
6 Wildfire Hazard and Risk Assessment Results................................................................................................ 65
6.1 Field Assessment Results ................................................................................................................... 65
6.2 Wildfire Hazard Modeling Results ...................................................................................................... 65
6.2.1 Flame Length ......................................................................................................................... 66
6.2.2 Burn Probability ...................................................................................................................... 66
6.2.3 Relative Wildfire Hazard ........................................................................................................ 66
6.3 Wildfire Progression Modeling ............................................................................................................ 68
6.4 Wildfire Mitigation Priority Assessment Results ................................................................................ 75
6.5 Critical Facilities Wildfire Exposure Assessment Results .................................................................. 79
6.6 Evacuation Routes and Traffic Calming Devices ............................................................................... 79
6.7 Tree Hazard Assessment Results ....................................................................................................... 80
7 Fire Suppression Zone Modeling ..................................................................................................................... 85
7.1 Fire Suppression Zone Modeling Methods ........................................................................................ 85
7.2 Fire Suppression Zone Modeling Results .......................................................................................... 86
7.3 Implications of Updated Fire Suppression Zone ............................................................................... 86
8 Wildfire Risk Reduction Recommendations .................................................................................................... 91
8.1 Vegetation Management ..................................................................................................................... 91
8.1.1 Wildland-Urban Interface Fuels Reduction Priority Recommendations ............................. 92
8.1.2 Wildland Fuels Reduction Priority Recommendations ........................................................ 92
8.1.3 Vegetation Management within Habitat Management Plan Areas Priority
Recommendations ................................................................................................................. 93
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8.2 Structural Ignitability ........................................................................................................................... 93
8.2.1 Structural Ignitability Priority Recommendations ................................................................ 94
8.3 Access and Evacuation ....................................................................................................................... 95
8.3.1 Access and Evacuation Priority Recommendations ............................................................ 96
8.4 Water Supply and Infrastructure ........................................................................................................ 99
8.5 Fire Department Resources ................................................................................................................ 99
8.6 Community Education and Outreach ................................................................................................. 99
9 References ...................................................................................................................................................... 101
TABLES
1 Land Use within the Plan Area ............................................................................................................................ 4
2 Carlsbad Fire Department Fire Stations and Staffing ........................................................................................ 7
3 Local Responsibility Area (LRA) Fire Hazard Severity Zone (FHSZ) Coverage ............................................... 19
4 Effects of Topographic Features on Fire Behavior .......................................................................................... 24
5 Vegetation Types in the Plan Area ................................................................................................................... 27
6 Fire Behavior Interpretation ............................................................................................................................. 40
7 Wildfire History within the City and Surrounding Lands ................................................................................. 41
8 Landscape Base File Input Data Sources ........................................................................................................ 56
9 Wildfire Behavior Modeling Weather Inputs .................................................................................................... 57
10 Relative Wildfire Hazard Classifications within the City’s Open Spaces ........................................................ 67
11 Relative Wildfire Hazard Classifications within the Plan Area’s Open Space ................................................ 75
12 Critical Facilities Wildfire Exposure .................................................................................................................. 79
13 Total Surveyed Trees......................................................................................................................................... 80
14 Surveyed Species of Concern ........................................................................................................................... 81
15 Tree Management Priorities ............................................................................................................................. 83
EXHIBITS
1 Examples of community areas with no setback from HMP areas .................................................................. 13
2 In the Box Canyon area, vegetation management within the existing 60-foot setback once
considered sufficient under past standards but no longer considered sufficient under
current standards. ............................................................................................................................................ 14
3 State minimum requirements for each Fire Hazard Severity Zone Class within the SRA and LRA. ................... 18
4 Open space area dominated by a mix of sage scrub and mature chaparral with patches of annual
grass near Poinsettia/Alicante and Alga Norte. .................................................................................................. 28
5 Photo Taken 2011 showing moderate-low load coastal scrub ....................................................................... 31
6 Photo Taken 2025 showing substantial increase in fuel loading ...................................................................... 32
7 Open space area south of La Costa Canyon High School dominated by a mix of mature chaparral
and coastal sage scrub with patches of annual grasses .................................................................................... 33
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8 Hosp Grove Park is adjacent to Monroe Street in the Carlsbad Village area. .................................................... 34
9 Flames during the 2014 Poinsettia fire well exceeding 20 feet. (Source: Daily Mail) .................................. 40
10 Wildland-urban intermix development at Green Valley Open Space .................................................................. 47
11 Mosaic open-space vegetation of coastal scrub, annual grasses, chaparral, and riparian/
woodland vegetation at Buena Vista Creek Ecological Reserve. ................................................................... 49
12 Calavera Lake Open Space .............................................................................................................................. 50
13 Relative Wildfire Hazard Classification Matrix................................................................................................. 58
14 Relative Wildfire Hazard Classification Matrix................................................................................................. 60
15 Example high priority areas throughout Carlsbad. ............................................................................................. 76
FIGURES
1 Plan Area .............................................................................................................................................................. 5
2 Fire Hazard Severity Zones ............................................................................................................................... 21
3 Plan Area Vegetation......................................................................................................................................... 29
4 Wildfire History .................................................................................................................................................. 43
5 Lands included in the Habitat Management Plan .......................................................................................... 53
6 Flame Length ..................................................................................................................................................... 69
7 Relative Wildfire Hazard ................................................................................................................................... 71
8 Fire Progression Model Results ....................................................................................................................... 73
9 Wildfire Mitigation Priority Results ................................................................................................................... 77
10 City Fire Suppression Zone ............................................................................................................................... 87
11 City Fire Suppression Zone (Development Areas) ........................................................................................... 89
12 Existing Wildland Pre-Plan Areas and Single Access Communities ............................................................... 97
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Executive Summary
The City of Carlsbad Wildfire Hazard and Risk Assessment (WHRA) provides a comprehensive assessment of the
wildfire regulatory framework, hazards, risks, and vulnerabilities affecting Carlsbad and establishes a strategic
framework for wildfire risk reduction. While Carlsbad has not historically experienced the same frequency of large
wildfires as inland San Diego communities, updated state hazard mapping, climate trends, increased fuel loading,
and an expansion of Wildland-Urban Interface development indicate that wildfire risk within Carlsbad has increased
substantially. This WHRA was prepared to aid the City in proactively addressing those risks, guide City investment
and policy decisions, and position the City to advance toward developing a Community Wildfire Protection Plan
(CWPP) with a strong technical foundation. The CWPP will build on the findings of the WHRA and incorporate
community and stakeholder input, public education and outreach, and refined project prioritization.
The WHRA is intended as a policy and guidance document, not a legally binding instrument. It provides
recommendations, best practices, and strategic priorities to help reduce wildfire risk, but it does not impose new
regulatory requirements or create enforceable obligations beyond those already established in existing laws, codes,
or ordinances. As such, the plan is designed to inform decision-making, support resource allocation, and guide
future actions. Implementation of its recommendations remains subject to separate approvals, funding
considerations, and applicable legal frameworks.
Increasing Wildfire Risk Citywide
Recent updates to Local Responsibility Area (LRA) State Fire Hazard Severity Zone (FHSZ) mapping have
significantly expanded wildfire hazard designations across Carlsbad, including a major expansion of the Very High
Fire Hazard Severity Zone (VHFHSZ). The VHFHSZ within the City now covers approximately a third of the City (8,169
acres), a 3,329-acre increase from the previous 2007 LRA FHSZ maps.
These changes reflect current conditions, including increased vegetation and fuel loads throughout the City, as well
as a better understanding of ember-driven wildfire risk in urbanized areas. They also expand the number of parcels
and structures subject to mitigation requirements, such as defensible space and ignition-resistant construction. As
a result, the City’s role in regulating, inspecting, and managing wildfire risk has grown significantly.
However, the City’s current mitigation approach, largely based on prior hazard designations, requires updating to
address the scale and complexity of these increasing wildfire hazards. Without adjustments to mitigation efforts,
the City may face challenges in effectively reducing wildfire risk.
Risks to Communities and Critical Facilities
Reflecting the City’s Growth Management Plan and long-standing community priorities for abundant open space
and trail systems, Carlsbad’s development pattern places many neighborhoods directly adjacent to open space,
canyon systems, ridgelines, and habitat preserves, resulting in widespread Wildland–Urban Interface (WUI)
conditions. In addition, schools, senior care facilities, and critical facilities are often located immediately next to
dense native vegetation capable of supporting high-intensity fire behavior. These conditions increase the
likelihood that wildfire could quickly transition from open space into developed areas, particularly during Santa
Ana wind events.
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A total of 55 critical facilities were evaluated as part of the WHRA. Approximately 40 percent were identified as
having high or very high wildfire exposure. Although many facilities are constructed to modern, ember-resistant
standards, field assessments found that defensible space is often inadequate. These conditions pose potential
risks to emergency response continuity, infrastructure operability, and public safety during wildfire events.
Defensible Space and Vegetation Management Constraints
The WHRA identifies widespread areas requiring improvement in defensible space along Carlsbad’s WUI edge,
where fuel modification buffers are absent or insufficient to mitigate expected fire behavior, especially on steep
slopes and in mature shrub fuels. In some areas, defensible space and adequate setbacks from hazardous
vegetation are entirely absent, exposing structures to a high risk of direct flame contact. These areas include
development adjacent to Habitat Management Plan (HMP) preserve lands with steep slopes and mature shrub
fuels, exposing structures to a high risk of direct flame contact. The City’s ability to address the absent or insufficient
fuel modification buffers in these areas is complicated by restrictions on vegetation management within preserve
lands which has constrained the City’s ability to reduce wildfire hazards adjacent to development, contributing to
elevated risk conditions in many areas.
Tree hazard assessments identified a substantial number of trees near critical infrastructure requiring near-term
management, including removal or pruning. Species such as eucalyptus, palms, pines, cypress, and juniper are
common and can increase ember production and fire intensity if unmanaged. Concentrated stands of eucalyptus
woodlands represent ongoing fuel hazards without sustained maintenance.
Modeled Wildfire Behavior and Fire Spread
Fine-scale wildfire modeling was conducted for the WHRA to supplement the statewide Fire Hazard Severity Zone
(FHSZ) maps and provide a higher level of detail and resolution. Unlike the statewide maps, which are designed for
broad classification, this modeling incorporates site-specific inputs such as vegetation type and continuity,
topography, weather patterns, and potential ignition locations to better characterize local fire behavior and risk.
Wildfire modeling indicates the potential for severe fire behavior throughout much of Carlsbad’s vegetated areas.
Since adoption of the City’s Habitat Management Plan (HMP) more than 20 years ago, vegetation growth and fuel
loading within the city have increased substantially. Predicted flame lengths frequently exceed thresholds
associated with ineffective fire suppression, particularly in chaparral and coastal sage scrub fuels. Fire progression
modeling further demonstrates that east–west oriented drainages and connected open-space corridors could allow
wildfire to spread rapidly from areas east of Carlsbad into residential neighborhoods and critical facilities, extending
wildfire exposure beyond the immediate wildland edge.
To identify areas of greatest wildfire risk, an assessment was conducted to evaluate and rank the relative need for
wildfire mitigation across developed areas. The resulting Wildfire Mitigation Priority Map establishes a framework
for targeting mitigation efforts within the Very High Fire Hazard Severity Zone (VHFHSZ) and other high-risk areas
not fully captured by statewide hazard modeling.
City Fire Suppression Zone Expansion and Operational Impacts
The City’s existing Fire Suppression Zone (FSZ) currently requires new development to implement the fuel
modification requirements provided in the City’s Landscape Manual. However, the existing FSZ does not reflect
current hazard conditions. Therefore, the FSZ was re-mapped to include the expansion of the VHFHSZ and fine-
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scale hazard modeling. The newly recommended FSZ has been expanded from approximately 9,000 acres to
nearly 13,800 acres. While not enforceable until adopted through City ordinance, this expansion would add more
than 7,200 parcels and bring an estimated 12,500 structures under enhanced wildfire mitigation requirements.
While this recommended change improves risk coverage and alignment with state standards, it significantly
increases inspection, enforcement, and administrative demands on City resources and underscores the need for
targeted prioritization.
Summarized Recommendations
Section 8 of the WHRA recommends a multi-faceted wildfire risk reduction strategy centered on vegetation
management and defensible space, ignitability, access and evacuation, community education and outreach, water
supply, and alignment of Fire Department resources with expanded responsibilities. Key recommendations for each
category include:
Vegetation Management:
▪ Increase the level of vegetation management within Carlsbad to mitigate substantial risks from wildfire.
▪ Establish a defensible space inspection program to mitigate wildfire risk for properties located within the
VHFHSZ and other high-risk properties. Utilize the Wildfire Mitigation Priority map to prioritize defensible
space inspections.
▪ Conduct and maintain vegetation management/fuel reduction around critical infrastructure and facilities,
major roadways, high-risk communities, and evacuation routes.
▪ Develop maintenance cycles for vegetation management projects in order to achieve long-term benefits.
Where possible, utilize Categorical Exemptions, Cal VTP, or other CEQA streamlining tools for the
environmental review process when planning and implementing vegetation management projects.
▪ Revise the City’s Landscape Manual Fuel Modification Zone guidelines to reflect the State Minimum
Standards for defensible space in the VHFHSZ (California Government Code § 51182).
▪ Expand existing fuel modification zones beyond 60 feet in areas where modeled fire behavior indicates that
this level of mitigation would be insufficient.
▪ Conduct hazard tree removal/management for high priority trees identified during risk assessment.
▪ Evaluate opportunities to develop grant, subsidy, or incentive programs to support property owners in
completing and maintaining defensible space.
Vegetation Management within habitat management plan preserve areas:
▪ As required by the HMP, develop a Fire Management Plan during the CWPP process to identify fuel reduction
zones within conserved lands. Ensure appropriate environmental review is conducted prior to implementing
fuel reduction projects within conserved areas.
▪ As stated in the City’s Open Space Management Plan, fire management guidelines within the Fire
Management Plan should be consistent with current accepted fire management mandates.
▪ Address and resolve limitations of the HMP that impede vegetation management activities attempting to
improve public safety
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Structural Ignitability:
▪ Refine the City’s Landscape Manual to include Zone 0 standards within fuel modification zones following
statewide adoption.
▪ Conduct structure inspections in tandem with existing defensible space inspection programs to educate
homeowners on the ignition resistance of their homes.
▪ Require new development within the City Fire Suppression Zone to be constructed to ignition-resistant
standards of Chapter 5 of the CWUIC (formerly Chapter 7A standards).
▪ Prioritize structural hardening of ember vulnerable critical facilities with a high degree of wildfire exposure.
▪ Encourage the Firewise USA program within Carlsbad to mobilize high-risk communities and improve
community-scale structural hardening efforts.
Access and Evacuation:
▪ Develop wildfire preparation plans for the Poinsettia and Kelley Ranch regions.
▪ Require formal emergency response delay assessments for proposed traffic calming devices, incorporating
evidence-based delay estimates to assess cumulative impacts on response times.
▪ Identify and designate priority evacuation corridors within the City’s General Plan Safety Element framework.
▪ As part of the CWPP, identify strategic roadsides to conduct vegetation management to prevent ignitions
and improve emergency access.
▪ Conduct targeted outreach and education within single-access communities.
▪ Reevaluate and remap single-access communities as part of the CWPP, and update the General Plan, as
appropriate, to more accurately reflect evacuation constraints and wildfire risk.
Community Education and Outreach:
▪ As part of the CWPP process, actively engage community members, neighborhood associations, and local
stakeholders to identify specific wildfire concerns, vulnerabilities, and priorities. Conduct public workshops,
surveys, and interactive mapping exercises to gather input on high-risk areas, evacuation challenges, and
preparedness needs.
▪ Utilize the CWPP process as an opportunity to enhance wildfire education, raise awareness about
defensible space, home hardening, and emergency planning.
▪ Increase community awareness and participation in Firewise USA programs.
▪ Promote and support the development of community programs, such as CERT and Community Fire Watch,
to build an informed, proactive, and engaged community in wildfire preparedness and response.
▪ Develop and distribute wildfire awareness materials (e.g., signage, QR codes) at popular recreation areas
to increase wildfire hazard awareness and reduce ignition risk.
▪ Conduct public outreach and education in communities where vegetation management projects are
proposed prior to initiating work.
Water Supply and Infrastructure:
▪ Prioritize and implement planned water infrastructure upgrades identified in the Potable Water Master
Plan, particularly those involving pipeline upsizing in areas with identified fire flow constraints.
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Fire Department Resources:
▪ The Carlsbad Fire Department should evaluate the level of additional personnel needed to effectively
implement inspection and enforcement activities within the expanded wildfire hazard areas. The study
should assess current inspection capacity, anticipated workloads associated with the expanded VHFHSZ
and Fire Suppression Zone, and the frequency of inspections required to maintain compliance.
▪ Allocate additional staff to assist with wildfire mitigation activities such as public education and outreach
during the CWPP process, developing fuel treatment plans, and updating the City Landscape Manual.
Conclusion
The findings of this WHRA demonstrate a significant wildfire risk within Carlsbad. Expanded hazard designations,
widespread WUI conditions, and limitations in existing mitigation approaches collectively contribute to high wildfire
risk within Carlsbad and the potential for structure loss. Addressing these challenges requires a shift toward more
proactive, data-driven wildfire mitigation strategies.
Implementation of the recommendations outlined in this WHRA will strengthen the City’s ability to reduce wildfire
risk, enhance community resilience, and protect critical infrastructure and public safety. This WHRA establishes a
strong technical and policy foundation for the forthcoming CWPP, which will further refine priorities and
implementation steps through community engagement and stakeholder collaboration. Continued coordination and
adaptive management will be essential to effectively respond to evolving wildfire conditions and ensure long-term
risk reduction.
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1 Introduction
Carlsbad is located in northern San Diego County along the Pacific coastline. Carlsbad’s landscape presents a
complex wildfire environment that poses significant risk to the built environment, including residential communities
and critical facilities. While Carlsbad has significant urban development, it also includes an extensive wildland–
urban interface (WUI) along the perimeter of open-space preserves distributed throughout. These WUI areas
increase wildfire vulnerability to adjacent homes, buildings, transportation corridors, and critical infrastructure.
Carlsbad and the surrounding region are also subject to seasonal Santa Ana wind events, prolonged drought, and
high temperatures. These conditions can intensify and accelerate wildfire spread, particularly through canyons and
open spaces where native vegetation and ornamental landscaping create continuous fuel beds that facilitate rapid
fire movement and long-range ember transport into developed areas.
Northern San Diego County, including Carlsbad, faces increasing wildfire risk due to a combination of environmental
conditions and ongoing development patterns. Although Carlsbad has not experienced the same frequency of large-
scale fires as some inland portions of the County, incidents such as the Poinsettia Fire (approximately 600 acres
burned and 28 structures destroyed) demonstrate the potential for destructive wildfire events within and adjacent
to the community.
This WHRA has been prepared to evaluate existing conditions, identify wildfire hazards and vulnerabilities, and
outline actions the City can take to reduce wildfire risk to the community. The WHRA provides a strategic framework
for prioritizing mitigation projects and identifies key risk-reduction strategies, including vegetation management,
structural hardening, and emergency preparedness to protect life, property, and critical resources. The WHRA
serves as a preliminary guide for implementing effective wildfire risk reduction measures and strengthening long-
term community resilience.
Following completion of the WHRA, the city will advance the planning process through Phase 2 with development
of a CWPP. The CWPP will build upon the technical analyses and preliminary project recommendations identified in
this WHRA and incorporate input from community members, regional partners, and key stakeholders. The CWPP
will also provide interactive mapping through a Project StoryMap. Through this collaborative process, the CWPP will
further refine and prioritize wildfire mitigation projects, identify implementation opportunities and resource needs,
and establish coordinated strategies for vegetation management, fuel treatments, and preparedness actions
across jurisdictions. This next phase will ensure that recommended projects reflect both local priorities and regional
wildfire risk reduction goals while fostering broad community support for implementation.
1.1 Purpose and Intent
The City recognizes the potential for significant loss of life, property, and natural resources from wildland fire. The
purpose of this WHRA is to identify and evaluate local wildfire hazards and risks and outline strategic actions that
can reduce those risks over time. This plan evaluates existing conditions, identifies areas of elevated wildfire hazard
and risk, and establishes an initial set of prioritized mitigation strategies. It also includes the development of
updated fire suppression zone mapping and a Wildfire Mitigation Priority map to guide resource allocation,
operational planning, and project prioritization within the city. Additionally, the WHRA evaluates the requirements
and constraints of the HMP as they relate to hazardous fuel reduction in preserve areas and offers
recommendations for carrying out work within these areas.
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Importantly, this WHRA is intended to serve as a foundational planning document to inform and support the future
development of a CWPP. While the WHRA provides a citywide technical assessment of wildfire hazards, risk, and
potential mitigation strategies, the subsequent CWPP will advance this work through a more detailed and
collaborative planning process. The CWPP will incorporate robust community engagement and coordination with
local interest holders, including residents, City staff, fire agencies, resource agencies, land managers, and other
interested parties, to further evaluate wildfire risk and refine mitigation priorities.
Through this process, the CWPP will use the hazard and risk assessments presented in the WHRA to more precisely
identify priority project areas, appropriate treatment methods, and implementation strategies. The result will be a
more detailed, community-informed roadmap that identifies actionable projects and guides long-term efforts to
reduce wildfire risk and strengthen wildfire resilience within the city.
1.2 Wildfire Hazard and Risk Assessment Goals
and Objectives
The following goals were identified during development of this WHRA:
▪ Identify areas of elevated wildfire hazard and risk throughout the city through field assessments and
GIS analysis.
▪ Utilize hazard and risk assessment findings to inform and guide wildfire mitigation strategies.
▪ Prioritize actions that reduce wildfire risk and protect identified values at risk.
1.3 Wildfire Hazard and Risk Assessment
Planning Process
The WHRA planning process was collaborative and involved close coordination among the Fire Department, other
City departments and technical specialists. The process was used to evaluate current wildfire conditions, identify
values and assets at risk, and develop mitigation strategies that reflect the City’s priorities toward wildfire risk
reduction. In addition to desktop analysis and modeling, the planning effort included targeted field assessments to
verify existing conditions and evaluate vulnerabilities on the ground. These field assessments focused on critical
facilities—such as emergency services infrastructure, utilities, and other essential community assets—to evaluate
surrounding vegetation conditions, potential exposure to wildfire, and opportunities to reduce risk through
defensible space improvements or vegetation management. Field reconnaissance also included an evaluation of
hazardous trees and vegetation conditions in areas where overgrown or structurally compromised trees could
contribute to wildfire spread, ladder fuels, or impacts to infrastructure during fire events.
Wildfire hazard and risk modeling played a central role in understanding potential fire behavior and identifying areas
where targeted treatments would most effectively reduce risk. The recommendations in this WHRA were developed
to address the specific wildfire hazards in Carlsbad and to support long-term community resilience, while also
providing a technical foundation that can be further refined during the future development of the CWPP.
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2 Plan Area Description
2.1 Location
Carlsbad is located in northern San Diego County (County) along the Pacific coastline. The Plan Area encompasses
approximately 25,011 acres (39.08 mi2) bounded by the Pacific Ocean on the west, Hwy 78 and the city of
Oceanside to the north and northeast, the cities of Vista and San Marcos to the east, unincorporated County lands
to the southeast, and the city of Encinitas to the south. U.S. Interstate 5 bisects the Plan Area from the north. The
Plan Area location is presented in Figure 1.
Carlsbad supports a diverse mix of coastal and inland habitat types that reflect its location along the southern
California coast and within a Mediterranean climate zone. Natural vegetation communities within Carlsbad include
coastal sage scrub, southern maritime chaparral, native and non-native grasslands, riparian corridors, and localized
areas of oak woodland and coastal wetlands. Coastal sage scrub is one of the most common upland habitats in the
area and is typically dominated by drought-adapted shrubs such as California sagebrush, California buckwheat, and
black sage. In areas with slightly deeper soils or less frequent disturbance, this vegetation transitions into chaparral
communities characterized by denser, taller shrubs, including chamise and manzanita.
The preserved open space areas of Carlsbad, which include, but are not limited to, coastal sage scrub, mixed
chaparral, grasslands, riparian corridors, and eucalyptus stands, frequently border developed neighborhoods and
critical infrastructure, forming an extensive WUI. Highly clustered development within Carlsbad creates a mosaic of
residential areas interspersed with open space corridors and preserved natural habitats. While this development
pattern helps concentrate urban growth and protect larger areas of natural landscape, it also results in numerous
locations where homes are directly adjacent to wildland vegetation. These open space corridors can also serve as
pathways for wildfire spread, increasing the potential for fire to move toward developed areas, especially during
extreme fire weather conditions.
This pattern of development creates an extensive WUI edge where built environments and natural vegetation meet.
The large amount of WUI edge in Carlsbad requires ongoing management and maintenance to reduce wildfire risk,
including vegetation management, maintenance of defensible space, and strategic fuel treatments within adjacent
open spaces. Effectively managing this interface is critical for reducing structure exposure to wildfire while
maintaining the ecological value of the City’s preserve land and open space network. When combined with the
region’s coastal Mediterranean climate and the influence of seasonal Santa Ana wind events, this landscape can
create conditions conducive to fast-moving, wind-driven wildfires (Westerling 2004).
2.2 Land Ownership and Land Use
The dominant land use within the Plan Area is recreation and open space, which accounts for approximately 23%
of the total area. Other major land uses include commercial (20%), public/institutional (19%), transportation and
utilities (13%), and residential (13%). Smaller portions of the Plan Area are dedicated to industrial (6%) and
agricultural (6%) uses. This mix of land use reflects the area’s balance between developed spaces and preserved
natural landscapes. See Table 1, Land Use within the Plan Area.
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Table 1. Land Use within the Plan Area
Land Use Classification Acres Percentage of Total
Residential 2,001 13%
Commercial 3,052 20%
Industrial 896 6%
Agricultural 855 6%
Public/Institutional 2,932 19%
Transportation/Utilities 1,932 13%
Recreation/Open Space 3,537 23%
Source: City of Carlsbad
Carlsbad is primarily composed of privately owned land for commercial and residential purposes; however, some
open spaces and habitat preserves are publicly accessible through partnerships with various organizations,
including the Center for Natural Lands Management, City-owned lands, the California Department of Fish and
Wildlife (CDFW), and the California Department of Parks and Recreation (CPAD 2025).
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2.3 Fire Protection
2.3.1 City of Carlsbad Fire Department
The City of Carlsbad Fire Department (CFD) provides a full range of fire protection, prevention, and community risk
reduction programs in the Plan Area. The department is staffed and equipped for structural fire protection and
wildland fire prevention, including full-time wildland fire specialists who lead vegetation management projects, one
staff member leading defensible space inspections, and the development of codes and standards for structure
hardening. These efforts are complemented by community education programs that promote preparedness and
reduce wildfire vulnerability.
CFD also plays a critical role in disaster mitigation and emergency planning, working with residents, businesses,
and partner agencies to ensure readiness for all hazards. In addition to local services, the City benefits from mutual
aid agreements and support from regional, state, and federal agencies to provide a coordinated response during
large-scale emergencies. This collaborative approach ensures that Carlsbad remains prepared to meet the
challenges of wildfires and other disasters while continuing to uphold its mission of safeguarding the community.
CFD was established in 1952 and is a multi-disciplinary municipal fire agency that responds to a variety of incidents,
including structure and vegetation fires, emergency medical services (EMS), hazardous materials incidents, water and
marine rescue, urban search and rescue, disaster response, and wildfire suppression. CFD is divided into two primary
bureaus—Emergency Operations and Community Risk Reduction—that operates seven fire stations, staffing six fire
engines and two reserves, one aerial ladder truck and a reserve, five ALS ambulances, three shift battalion chiefs who
lead A, B, and C platoons, and cross-staffed Type 3 wildland engines and technical rescue resources. CFD is budgeted
for approximately 111 full-time personnel, with daily staffing of 33 firefighters across the seven fire stations and
responds to an average of 15,000 service calls each year, the majority of which are medical calls. Table 2 provides the
location and staffing of the department’s seven fire stations.
Table 2. Carlsbad Fire Department Fire Stations and Staffing
Fire Station Address Staffing
1 1275 Carlsbad Village Dr. Crew of five: captain, engineer, two paramedic/firefighters and
one emergency medical technician
2 1906 Arenal Rd. Crew of five: captain, engineer, two paramedic/firefighters and
one emergency medical technician
3 3465 Trailblazer Way Crew of five: captain, engineer, two paramedic/firefighters and
one emergency medical technician
4 6885 Batiquitos Dr. Crew of three: captain, engineer and paramedic/firefighter
5 2540 Orion Way Crew of four: duty battalion chief, captain, engineer, and
paramedic/firefighter
6 7201 Rancho Santa Fe Rd Crew of five: captain, engineer, two paramedic/firefighters and
one emergency medical technician
7 4600 Carlsbad Blvd. Crew of six: captain, engineer, three paramedic/firefighters and
one emergency medical technician
CFD is responsible for wildfire suppression and prevention within the City’s Local Responsibility Area (LRA). The
department maintains mutual aid agreements with the cities of Oceanside, Vista, Encinitas, San Marcos, and the
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Rancho Santa Fe Fire Protection District, and participates in regional dispatch through North County Dispatch Joint
Powers Authority (NCDJPA or North Comm), which serves 15 fire agencies across North San Diego County. CFD is
also a member agency of California Task Force 8 (CA-TF8) and Cal OES Regional Task Force 13, supporting
statewide urban search and rescue operations during large-scale National or regional emergencies.
2.3.2 Fire Protection Partnerships
As previously described, CFD serves as the Authority Having Jurisdiction (AHJ) within the City of Carlsbad. This role
includes managing mutual aid and automatic aid agreements within and beyond city boundaries. Automatic aid
refers to a contractual agreement between agencies or fire districts in which assistance is dispatched immediately
to first alarms. In contrast, mutual aid is typically activated upon request by the primary responding agency when
additional resources are needed.
Additional support is provided through established automatic aid agreements with nearby jurisdictions, as well as
local mutual aid within the operational area, including resources from the San Diego County Fire Protection District,
CAL FIRE, the North County Fire Protection District, and other neighboring agencies. In the event of a large-scale
wildfire or disaster, the State of California coordinates the mobilization of resources through the statewide mutual
aid system, and, if necessary, requests assistance from federal and interstate partners to ensure a comprehensive
and effective response.
2.4 Existing Fire Risk Reduction Programs
Fuel modification zones and defensible space requirements are cornerstone elements of the City of Carlsbad’s
wildfire risk reduction framework. These measures are designed to reduce wildfire intensity and rate of spread, limit
ember exposure, and improve structure survivability in areas where development interfaces with fire-prone
vegetation. This section describes the City’s fuel modification zone requirements, associated vegetation treatment
standards, and inspection and maintenance protocols, which collectively support long-term wildfire resilience and
compliance with adopted fire protection regulations.
2.4.1 Fire Codes and Ordinances
Fire protection within Carlsbad is governed by a combination of locally adopted ordinances and state regulations
designed to reduce fire hazards, strengthen emergency response, and improve community resilience. As mentioned
in Section 2.3, these regulations are implemented and enforced by the CFD through development review processes,
fire prevention inspections, and ongoing code compliance enforcement.
The City has formally adopted the 2025 California Fire Code (CFC), 2025 California Wildland-Urban Interface Code
(CWUIC), through Ordinance No. CS-500, which establishes the local authority for fire prevention regulations,
construction standards, vegetation management, and enforcement within WUI areas. The adopted WUI Code is
codified as Carlsbad Municipal Code Chapter 17.06, which incorporates the 2025 CWUIC in its entirety, with specific
local amendments driven by Carlsbad-specific climatic, geological, and topographical conditions.
The 2025 CWUIC establishes minimum requirements to reduce the likelihood of life and property loss due to wildfire
in designated Fire Hazard Severity Zones and Wildland‑Urban Interface areas. The CWUIC organizes wildfire‑related
requirements into a unified framework that consolidates applicability, construction standards, defensible space,
access, and fire protection systems. Chapter 3 consolidates statutory authority and standardizes applicability
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determinations using State Fire Marshal Fire Hazard Severity Zone maps. Chapter 4 aligns defensible space,
access, and water supply requirements with the State Minimum Fire Safe Regulations and clarifies administrative
cross‑referencing. Chapter 5 relocates ignition‑resistant construction requirements formerly found in CBC Chapter
7A into the CWUIC, addressing ember exposure and exterior component vulnerability. Chapter 6 consolidates
wildfire‑specific fire protection provisions previously located in CFC Chapter 49, without materially altering system
design criteria or operational mitigation measures. Taken together, these chapters provide a comprehensive
statewide framework for ignition‑resistant construction, defensible space, and wildfire‑resilient site development.
The CFC and CWUIC establish minimum fire protection requirements addressing fire apparatus access, water
supply, ignition-resistant construction, defensible space, and vegetation and fuel management. Ordinance No. CS-
500 amends several 2025 CWUIC provisions to address local wildfire hazards, including enhanced vegetation
management compliance requirements (CMC §17.06.020), which mandate that properties demonstrate
compliance with vegetation clearance standards prior to final building permit approval. These requirements for
zones within 5 feet, 30 feet, and 100 feet of structures, and landscape or fuel modification plans must identify
vegetation, irrigation, plant materials, and groundcover treatments within these zones. Additional amendments to
the CWUIC Chapter 6 strengthen ongoing vegetation and fuel maintenance obligations, requiring continuous
upkeep and authorizing enforcement under Section 109.
2.4.2 Habitat Management Plan
The HMP was adopted in 2004 as a citywide conservation and land use strategy under the regional Multiple Habitat
Conservation Program (MHCP). The MHCP provides an ecosystem-scale planning framework across San Diego
County’s North County jurisdictions, while the City’s HMP serves as the implementing document at the local level
guiding preservation, development, impact mitigation, and long-term management of approximately 6,478 acres of
habitat and open space.
The HMP was prepared in coordination with federal and state wildlife agencies and adopted to support issuance of
incidental take permits under the state and federal Endangered Species Acts and California Natural Communities
Conservation Planning Act. It has been implemented on an ongoing basis through development approvals, preserve
acquisition, and active habitat management. An associated Implementing Agreement defines responsibilities for
the city and wildlife agencies, including conservation, monitoring, and management obligations, while allowing
incidental take authorization for covered activities. The city encompasses over 100 preserves with multiple
landowner types including city-owned lands, CDFW/State Parks, and private ownership.
In addition, the City’s Open Space Management Plan establishes policies and standards for managing HMP hardline
preserves, including addressing threats to native species and habitats, habitat restoration, public access, and
vegetation management. It also addresses fuel management constraints and allowable activities within conserved
lands, directly influencing how wildfire risk reduction can occur in these areas.
Within areas governed by the HMP, fire management activities are limited and carefully controlled with the intent
to balance wildfire safety with the protection of sensitive biological resources. In general, the HMP prioritizes
avoiding direct disturbance within preserved habitat areas, meaning most vegetation management required for
wildfire protection is intended to occur outside preserve boundaries as part of development design and defensible
space planning.
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For development adjacent to HMP preserves, that occurred after the adoption of the HMP, wildfire risk reduction
is primarily addressed through setbacks and fuel modification zones located within the development footprint rather
than inside the preserve itself. Fuel Modification Zones 1 and 2, as detailed in the City’s Landscape Manual, are
typically prohibited within designated open space areas to prevent impacts to conserved habitat, although limited
vegetation management may be allowed in certain cases, such as older preserves that were established prior to
HMP adoption
2.4.2.1 Vegetation Management Framework within the HMP
Preserve Areas
Most vegetation management within preserve areas is conducted for the purpose of habitat enhancement;
however, the HMP allows targeted fuel management activities when necessary for public safety, but these actions
must be conducted in accordance with an adopted Fire Management Plan, coordinated and implemented in a way
that minimizes impacts to sensitive species and habitats (HMP Section F.3.A). Acceptable methods may include
mechanical fuel treatments such as mowing, trimming, hand clearing, crushing, chopping, or selective removal of
vegetation, particularly in smaller fragmented preserves where fire could threaten nearby development. In larger
preserve areas, prescribed burning may be considered feasible, although it must be carefully planned due to safety,
ecological, and logistical considerations.
Overall, the HMP framework emphasizes that wildfire management in preserved habitat areas should focus on
strategic fuel reduction, maintaining fire access routes, and protecting adjacent communities, while ensuring that
conservation objectives remain the primary management priority within the preserve system.
The City’s HMP (Section F.3.A) allows the CFD to conduct fuels reduction for public safety and provides management
recommendations related to wildfire management including a Fire Management Plan which should, to the degree
feasible, be consistent with the recommendations of the Wildland/Urban Interface Task Force, and
1. Identify potential fuel reduction zones or firebreak locations as well as access routes for fire equipment in
the event of wildland fires that pose safety concerns.
2. To the degree feasible, site fuel reduction zones, firebreaks, and access routes to avoid sensitive biological
resources, preferably at the top or bottom of a slope rather than across a slope. Use existing firebreaks
(e.g., natural ridge lines, roads, fire roads) where available.
3. In smaller fragmented preserve areas, manage fuel loads primarily for human safety, using mechanical fuel
control measures such as chopping, crushing, disking and chaining, removal, and herbicides. Additional
methods of value in smaller areas include mowing, trimming, and hand clearing. In general, chopping and
crushing are the recommended methods based on biological and fuel reduction values and safety concerns.
Crushing with a device called a “sheep’s foot” may be an alternative form of fuel control in some situations.
4. In larger preserve areas, such as in northeast and southeast Carlsbad (Core Areas 5 and 7), manage both
for biological resources needs and for safety considerations. Use prescribed burning, where practical, given
safety and cost considerations. Fire management practices should be based primarily on the risks of
uncontrolled wildfire in proximity to developed areas.
Additionally, the OSMP requires preparation of a citywide Fire Management Plan to guide implementation and was
identified as Key Issue (#6): “Fire management will be consistent with the recommendations of the Wildland/Urban
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Interface Task Force (San Diego County Fire Chief’s Association 1997) or the equivalent current accepted regional
fire management guidelines document” (OSMP 3.1.4, P. 3-13).
The CFD has authority to require fuel management to achieve the minimum standards for defensible space. The
HMP and implementing documents allow for fuel management zones to encroach into the preserve for safety
reasons if unavoidable. However, impacts from the encroachment require additional mitigation. The HMP also
states that fuel management for existing developed areas may extend into the preserve to provide adequate wildfire
protection. When the HMP was adopted, California Government Code 51182 required defensible space around
occupied dwellings or structures in the VHFHSZ and lands that are in, upon or adjoining brush-covered land, or any
land that is covered with flammable material, and to all times maintain a firebreak by removing and clearing away,
for a distance of not less than 30 feet, flammable vegetation or other combustible growth. Additional fire breaks
from 30 feet to 100 feet could be required by the local agency if the local agency determined, because of extra
hazardous conditions, a firebreak of only 30 feet was not sufficient to provide reasonable fire safety. Currently,
these minimum state requirements are expanded to 100-feet of clearance rather than the 30-feet requirement at
the time of the HMP’s adoption.
In contrast, for new development, required brush management and fuel modification measures are incorporated
within the development footprint and are designed to avoid encroachment into designated preserve areas.
Fuels reduction activities within HMP areas should be identified through a Fire Management Plan developed in
coordination and agreement with the U.S. Fish and Wildlife Service and the California Department of Fish and
Wildlife, as required by the HMP. These treatments would occur adjacent to developed areas and would be designed
to meet the state’s minimum requirements for fuel modification zones. All fuel management efforts would aim to
achieve fire safety objectives while minimizing impacts on the environment and sensitive species through
management practices outlined in the HMP.
Prior to conducting fuels reduction work within HMP areas, environmental review would be completed to identify,
avoid, and minimize potential impacts to sensitive plant and animal species and their habitats. This review would
be conducted in accordance with the California Environmental Quality Act (CEQA), HMP permitting, special permits
for actions in wetlands and riparian areas, where applicable, other requirements such as the state or federal
Endangered Species Acts. Potential CEQA compliance pathways for the CFD to consider include:
▪ Tiering from the 2003 Final Environmental Impact Statement/Environmental Impact Report for Threatened
and Endangered Species Associated with Urban Growth within the Multiple Habitat Conservation Program
Planning Area, pursuant to the California Environmental Quality Act tiering provisions (CEQA Guidelines §§
15152 and 15168, as applicable)
▪ Preparation of a Project-Specific Analysis (PSA) for fuels treatment activities within the city, tiered from and
relying on the California Vegetation Treatment Programmatic Environmental Impact Report for
programmatic-level impacts, and focusing on site-specific environmental effects, consistency with the
program, and applicable mitigation measures
▪ Utilization of CEQA Categorical Exemptions or other Statutory Exemption Pathways
Prior to conducting fuels reduction activities, pre-project biological surveys would be conducted by qualified
biologists to document existing conditions, identify special-status species, and map sensitive habitats. Surveys may
be seasonally timed to detect particular species (e.g., nesting birds, rare plants, or amphibians). If sensitive
resources are present or have the potential to occur, the project would incorporate avoidance and minimization
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measures, such as establishing protective buffers, limiting work to certain times of year (e.g., outside nesting
season), and adjusting treatment methods or footprints.
The Governor’s office has issued multiple emergency proclamations and executive orders directing state agencies
to accelerate fuels reduction projects to better protect communities from wildfire. These directives include efforts
to streamline environmental review and improve coordination among state and federal wildfire and resource
agencies. Accordingly, the California Department of Fish and Wildlife and the U.S. Fish and Wildlife Service are
expected to coordinate with the fire department to facilitate implementation of fuels reduction projects within HMP
areas, consistent with applicable environmental requirements, to meet state minimum standards and reduce the
risk of significant wildfire impacts.
2.4.2.2 Current Issues Related to Vegetation Management Within HMP
Preserve Areas
There are currently differing interpretations of what vegetation management activities are permitted within HMP
preserve areas, resulting in inconsistent implementation along much of the City’s WUI. Consequently, many
locations lack adequate separation between structures and adjacent wildland vegetation. In some areas, existing
60-foot fuel modification zones are insufficient to mitigate anticipated wildfire behavior. Additionally, current
restrictions limit the ability to achieve the State-recommended minimum of 100 feet of defensible space, as
adopted by the City, further increasing structure vulnerability.
As a result, portions of the HMP preserve are effectively out of alignment with current State minimum requirements
and the City’s municipal code, which incorporates the California Wildland-Urban Interface Code (CWUIC).
As described in Section 2.4.2.1, the HMP requires the City to adopt a formal Fire Management Plan to identify
fuel reduction zones, potential firebreak locations, and access routes for fire equipment during wildland fire
events. However, such a plan has not been developed in a manner that meets the four key criteria outlined in
the HMP (HMP Section F.3-A). With the implementation of the Fire Management Plan, it is anticipated that the
City of Carlsbad may conduct brush management within the preserve to prevent the loss of human life and
property from wildfire.
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Exhibit 1. Examples of community areas with no setback from HMP areas
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Exhibit 2. In the Box Canyon area, vegetation management within the existing 60-foot setback once considered
sufficient under past standards but no longer considered sufficient under current standards.
2.4.3 Fuel Modification Zone Requirements
Fuel modification zones (FMZs) are a primary wildfire risk reduction strategy utilized by the city to reduce fire
intensity, slow rates of spread, and minimize the likelihood of direct flame contact and ember exposure to structures
located adjacent to hazardous vegetation. These zones establish prescribed vegetation treatment and maintenance
standards within defined setback areas between development and wildland fuels and are implemented in
accordance with the City of Carlsbad Landscape Manual and Fire Protection Requirements.
FMZs are required for new development or redevelopment projects that are in a Fire Suppression Zone or within a
VHFHSZ or otherwise determined by the Fire Code Official to require additional wildfire protection measures. The
configuration and treatment standards for fuel modification zones vary depending on slope condition, vegetation
type, and location relative to structures or property boundaries, but generally provide a minimum of 60 feet of
defensible space between development and high-risk wildland fuels for development in a Fire Suppression Zone.
Under current standards for new development or reconstruction in a VHFHSZ, 100 feet of defensible space is
required. A reduced distance can be provided if it is determined, based on fire behavior analysis and methodology
approved by the Fire Marshal, that the reduced distance provides an equivalent level of fire protection and same
practical effect.
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All FMZs implemented within Carlsbad are required to be maintained in perpetuity by the responsible property
owner, homeowners’ association, or other designated maintenance entity. However, inspections of FMZs are not
required and are currently performed on a voluntary basis.
Priority recommendations related to the City’s Fuel Modification Zone standards are presented in Section 8.1.
2.4.4 Annual Hazard Reduction/Weed Abatement Program
The City implements an annual Hazard Reduction Program to eliminate fire hazards associated with dry weeds,
brush, rubbish, and other combustible materials on vacant or unmanaged private property. In alignment with
California Government Code Sections 39560-39588, the City Council is authorized to declare weeds, rubbish, and
refuse on private property to be public nuisances, enabling enforcement actions to reduce fire risk. As part of the
2025 program cycle, the CFD completed its annual hazard survey and identified 187 parcels with existing or
potential fire hazards during the dry season, when wildfire risk is elevated.
2.4.5 Defensible Space Inspections
WUI fuel reduction is also part of the requirements of WUI building codes (e.g., California Wildland-Urban Interface
Code), defensible space, and other structure hardening and fire safe development requirements required by the
city. Defensible space is an effective means of reducing the risk of loss of life and property due to wildfire. Defensible
space works to achieve four objectives: reduce the risk of direct flame contact with a structure, reduce the overall
fire intensity and rate of spread near a structure, remove ember sources and provide space for embers to fall to the
ground before reaching the structure, and provide an area for firefighters to safely engage with fire and access
structures. A defensible space zone around an entire structure has been proven to be effective for achieving these
objectives (Syphard et al. 2014). Conversely, the lack of defensible space near a structure has been shown to be a
key factor in structure ignition during wildfires (Troy 2020).
Research suggests that maintaining effective defensible space can significantly reduce the likelihood of home
ignition (Zamanialaei et. al, 2025; Syphard et. al, 2014). Defensible space inspections are therefore critical, as they
ensure these vegetation management standards are properly implemented and consistently maintained over time,
significantly improving a structure’s survivability during wildfire events.
The city does not have a comprehensive, citywide defensible space inspection program. Instead, inspections are
conducted on a limited, voluntary basis at approximately 48 locations. While fuel modification zones and defensible
space areas are subject to applicable vegetation clearance and wildfire risk reduction standards, most properties
are not routinely inspected by the CFD. However, CFD does inspect and cite vacant lots that are in violation of the
City’s weed abatement requirements.
Where inspections do occur, a Fire Inspector conducts site visits and may provide written documentation regarding
general conformance with the City’s vegetation clearance requirements and California Government Code Section
51182. Clearance work should avoid unnecessary removal of vegetation, preserve native vegetation where
feasible, and comply with applicable environmental regulations. Where impacts to protected habitat or species
cannot be avoided, appropriate mitigation measures may be required in coordination with applicable local, state,
or federal resource agencies.
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Inspection criteria may include, but are not limited to, the following:
▪ Removal of dead and dying portions of trees located adjacent to or overhanging buildings
▪ Clearance of any portion of a tree extending within 10 feet of a chimney or stovepipe outlet
▪ Maintenance of roofs free of leaves, needles, or other dead vegetative material
▪ Removal of dead or dying plant material throughout the property
▪ Cutting and maintenance of annual weeds and grasses to a height below 4 inches
▪ Maintenance of appropriate horizontal and vertical separation between trees and shrubs to reduce fuel
continuity and ladder fuels, consistent with the City of Carlsbad Landscape Manual (Section 5)
In cases where significant deficiencies are observed during these limited inspections, property owners may be
notified of recommended corrective actions. A major recommendation of this WHRA is the implementation of an
expanded Defensible Space Inspection Program to help ensure defensible space compliance across the city. See
Section 8.1.1.1 for a detailed description of this recommendation.
2.4.6 Annual Fire Inspection Program
Annual fire inspections are required by the California Health and Safety Code, which mandates yearly inspections
of apartments and condominiums with three or more units, hotels and motels, lodging houses, and all public and
private K-12 schools. These inspections reduce fire risk, prevent property loss, and maintain the community’s
overall safety. During these inspections, the CFD staff evaluate key life-safety features such as fire protection
systems, exits and egress paths, fire-resistive construction, and fire department access, ensuring buildings comply
with state fire, building, and maintenance codes (City of Carlsbad 2025).
2.4.7 Community Education and Engagement
The CFD actively engages with the community to promote education on wildfire risk mitigation and
preparedness, recognizing that an informed and involved public is essential to reducing wildfire impacts. This
effort includes hosting community meetings, workshops, and outreach events that provide residents with
practical information on defensible space, home hardening, evacuation planning, and emergency readiness.
The goal is to increase community awareness, empower individuals to take proactive steps to protect their
properties, and strengthen overall participation in wildfire risk reduction efforts, ultimately enhancing the
resilience and safety of the entire community.
2.4.7.1 Firewise Communities
The Firewise USA® program, led by the National Fire Protection Association (NFPA), is a nationwide initiative that
helps communities reduce their risk from wildfires. It focuses on empowering residents to take responsibility for
preparing their homes and neighborhoods, particularly in areas where development meets natural vegetation. By
providing guidance, tools, and resources, the program helps communities understand their specific wildfire risks
and take practical steps to address them.
Through the Firewise USA® program, communities organize local groups, assess hazards, and create action plans
to improve safety. These efforts often include maintaining defensible space around homes, using fire-resistant
materials, and improving emergency access and evacuation readiness. By encouraging collaboration between
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residents, fire agencies, and local organizations, the program builds long-term awareness and participation,
ultimately strengthening a community’s resilience to wildfire threats.
Carlsbad currently includes four registered Firewise communities including:
▪ Rancho Carrillo Firewise Council
▪ La Costa Greens
▪ La Costa Alta Community
▪ Community of Brookfield
The CFD should aim to expand involvement in the Firewise USA® program by adding three new participating
communities each year.
2.4.7.2 ALERT California Fire Detection
The CFD partners with homeowners’ associations on vegetation maintenance and provides public education on
wildfire prevention. On July 29, 2025, the City Council advanced these efforts by approving a plan to explore the
installation of wildfire monitoring cameras on city-owned properties as part of a partnership with the Carlsbad
Municipal Water District and the University of California San Diego’s ALERT California program. The ALERT California
network consists of more than 1,100 high-definition cameras that provide real-time, 360-degree visibility, night-
vision capability, and remote pan-tilt-zoom features to support early wildfire detection and situational awareness
for first responders.
In September 2025, a new ALERT California camera was successfully installed in the La Costa Ridge community,
expanding regional monitoring coverage and improving early detection and response coordination (City of Carlsbad
2025). These cameras are designed to monitor natural hazards exclusively and incorporate privacy safeguards
such as automatic blurring when homes appear in view. For more information, see www.alertcalifornia.org
2.4.8 Countywide Chipping Events
San Diego County provides Community Chipping Events that Carlsbad residents may participate in when an event
is scheduled within or near Carlsbad. These events offer residents a free and convenient way to dispose of brush,
branches, and excess vegetation that accumulate during routine yard maintenance and defensible space
preparation. By making it easier for homeowners to remove dry vegetation, the program supports regional wildfire
prevention efforts and helps reduce accumulated fuel that can significantly increase fire intensity during the dry
season (County of San Diego 2025).
Participation in these events is open to residents who live in the area surrounding each event. Homeowners are
encouraged to gather tree branches, brush, and shrubs from their property and transport the material to the
designated chipping location to be processed and disposed of.
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2.5 Fire Hazard Areas
2.5.1 State Fire Hazard Severity Zones
Fire Hazard Severity Zones (FHSZs) are geographical areas designated pursuant to California Public Resources
Code (PRC) Sections 4201-4204 and California Government Code Sections 51175-51189. FHSZs are classified as
Very High, High, or Moderate in the State Responsibility Areas (SRA) and Local Responsibility Area (LRA).
PRC Sections 4201–4204 and California Government Code Sections 51175–51189 direct CAL FIRE to map areas
of significant fire hazard based on fuels, terrain, weather, and other relevant factors. The resulting FHSZs define
the application of various mitigation strategies to reduce the risk associated with wildland fires (Exhibit 4) (OSFM
2026). The model used to determine the extent of FHSZs in wildland areas is based on an analysis of potential fire
behavior and fire probability. In non-wildland areas, FHSZ classifications are based on adjacent hazard and ember
production from wildland areas, and urban factors such as slope and tree canopy cover. Structures built in High
and Very High FHSZs within Carlsbad are subject to more stringent fire-hardening and defensible space
requirements than those that are not.
Exhibit 3. State minimum requirements for each Fire Hazard Severity Zone Class within the SRA and LRA.
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Carlsbad was included in the recent update to the State’s FHSZ Maps for LRA (March 2025). These updated maps
now include classifications for Moderate and High Fire Hazard Severity within the LRA and have greatly increased
the extent of the (VHFHSZ within Carlsbad. Compared to the prior maps (2007), the VHFHSZ within Carlsbad has
increased by 3,329 acres, placing a much larger demand on CFD for defensible space inspections, hazard
disclosures, and ensuring structural hardening components are included in new construction.
The values presented in Table 3 include the FHSZ acreage and percent coverage of Carlsbad for both the previous
(2007) and current (2025) FHSZ designations. As presented, Carlsbad saw a 3,329-acre increase in Very High
designation, a 4,299-acre increase in High designation, and a 1,796-acre increase in Moderate designation. The
current Fire Hazard Severity Zoning designations are presented graphically in Figure 2.
Table 3. Local Responsibility Area (LRA) Fire Hazard Severity Zone (FHSZ) Coverage
Fire Hazard
Severity Zone Acres (2025)
Percent of City
(2025)
Number of
Parcels
(2025) Acres (2007)
Percent of
City (2007)
Very High 8,169 32.7% 7,941 4,840 19%
High 4,299 17.2% 3,878 NA NA
Moderate 1,796 7.2% 2,493 NA NA
While FHSZ designations identify areas of heightened wildfire hazard, they do not function as operational fire
response or suppression boundaries. Instead, they establish the regulatory framework under which ignition-
resistant construction standards, defensible space requirements, and wildfire-related disclosure obligations apply.
Properties located within High and Very High FHSZ are subject to enhanced wildfire protection, planning, and
mitigation measures consistent with the City’s Fire Suppression Zone as described below.
2.5.2 Carlsbad Fire Suppression Zone
As described in Section 2.4.1, wildfire hazard areas within Carlsbad are implemented locally through the adoption
of the State Fire Hazard Severity Zone (FHSZ) maps. These designations provide a regulatory framework that guides
how wildfire risk is managed at the municipal level and informs land use planning, development standards, and
wildfire mitigation requirements throughout Carlsbad (Exhibit 4). By integrating these state-mapped hazard zones
into local policy, the City ensures that new development and existing structures adhere to defensible space, fuel
management, and fire-resistant design standards appropriate for areas at elevated wildfire risk.
In addition to applying these standards to development located within the VHFHSZ, CFD extends the defensible
space and fuel modification requirements outlined in the City’s Landscape Manual to structures situated within the
City’s Fire Suppression Zone. As discussed further in Section 7, refinements to the boundaries of the Fire
Suppression Zone have been proposed as part of this WHRA to incorporate additional lands classified as VHFHSZ
and those where Carlsbad-specific hazard modeling warrants inclusion. These refinements have resulted in a
substantial increase in the total area subject to the City’s Fire Suppression Zone requirements—from 9,000 acres
to 13,799 acres. The expansion of the VHFHSZ along with the findings of the Relative Wildfire Hazard modeling
(See Section 5.3.3) adds an additional 7,214 parcels to the City’s Fire Suppression Zone, bringing the total number
of parcels within this zone to 13,414 and the total number of structures to roughly 12,500.
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These proposed Fire Suppression Zone updates strengthen the City’s ability to manage wildfire risk proactively,
ensuring that both public and private lands within high-risk areas are subject to consistent, enforceable standards
for vegetation management, defensible space, and structural protection.
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3 Wildfire Environment
3.1 Climate
San Diego County’s weather is defined as arid subtropical, which generally consists of hot, dry summers followed
by mild winters with periodic rain. This region has characteristics of a Mediterranean climate with several
microclimates existing in the County due to the influence of arid continental climate to the east and the Pacific
Ocean to the west. As such, conditions are variable on a daily and seasonal basis throughout the County.
Microclimatic conditions can greatly affect fire hazards and would be considered when determining vegetation
treatments and implementation timing. Such conditions are often not captured in weather station datasets or
recorded in easily referenced weather almanacs but are usually well known to locals, land managers, and local fire
agency personnel. Carlsbad is situated within the Maritime and Coastal Climate Zones for San Diego County, which
generally produce higher relative humidity compared to inland areas. Nevertheless, localized microclimates within
Carlsbad, particularly in the eastern portions, can result in significantly lower humidity and elevated wind speeds,
creating conditions more conducive to wildfire spread.
Carlsbad’s climate is influenced by the Pacific Ocean and is frequently under the influence of a seasonal, migratory
subtropical high-pressure cell known as the “Pacific High” (WRCC 2025). The regional prevailing wind pattern varies,
and the presence of the Pacific Ocean causes a diurnal wind pattern known as the land/sea breeze system. During
the summer season, the diurnal winds can be slightly stronger than the winds during the winter season due to
greater pressure gradient forces. These winds, while not as strong as Santa Ana winds, can contribute to fire
hazards when appropriate conditions exist for wildfire ignition and spread. Surface winds can also be influenced
locally by terrain variations. The varied terrain of the Plan Area also affects wind velocity and patterns, where the
highest wind velocities are typically associated with downslope, canyon, and Santa Ana winds (Keeley and
Fotheringham 2003). Santa Ana wind conditions are a reversal of the prevailing onshore winds that usually occur
on a region-wide basis during late summer and early fall. These winds are warm, dry winds that flow from the
warmer, drier inland area to the east towards the coast.
Santa Ana winds typically occur in late fall but have been documented between September and April, with peak
intensities often occurring in late fall and early winter, when high-pressure systems over the Great Basin drive hot,
dry air downslope toward the coast. This weather pattern produces extremely low humidity and strong winds—often
with gusts exceeding 40 to 60 miles per hour—which rapidly dry vegetation and contribute to high rates of fire
spread and long-distance ember transport during severe wildfire conditions (Billmire 2014).
Under these conditions, fires that might otherwise remain relatively small can quickly escalate and spread across
large areas, threatening nearby communities in the WUI within a short period of time. While coastal influences can
moderate some wind speeds compared to more inland areas of San Diego County, Santa Ana events can still
generate significant winds within Carlsbad. Sustained wind speeds of approximately 26 miles per hour have been
recorded locally, with higher gusts occurring during stronger events, creating conditions capable of supporting rapid
wildfire growth and ember-driven structure ignition.
During Santa Ana wind events, a notable “eddy” phenomenon can also occur. After the peak Santa Ana phase
weakens, the atmosphere often undergoes a transitional period where the warm offshore air that had surged
westward is replaced by the region’s typical onshore flow. When this marine onshore pattern begins to reestablish
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itself, it can push the previously warmed air mass back inland, creating localized eddies and wind reversals along
the coast. Although this return flow tends to be weaker than the original offshore Santa Anas, it can reintroduce
warm, dry air inland and prolong fire‑weather conditions, especially because fuels remain critically dry after the
initial offshore wind event and humidity takes time to recover. This combination of oscillating wind directions,
lingering heat, and pre‑dried vegetation compounds fire risk by sustaining ignition potential and enabling erratic
fire behavior, even after the strongest Santa Ana winds have subsided.
3.2 Terrain
Carlsbad’s total area encompasses 39.1 square miles and includes 7 linear miles bordering the Pacific Ocean.
Carlsbad is very topographically diverse and includes features such as coastal areas, hills, and valleys with
significant differences in elevation, slope, and aspect. Carlsbad’s topography is characterized by east-west running
low and broad ridgelines separated by wide, flat valleys that create a diverse and visually distinct landscape.
Carlsbad transitions from low-lying coastal plains near the Pacific Ocean to steep canyons and elevated ridgelines
further inland, such as those found along Calavera Hills, Dawson, Los Monos Canyon, and Box Canyon. These east–
west-trending ridges are separated by wide valleys and drainage corridors, forming a complex terrain pattern that
influences both local weather and wildfire behavior. Ridge-top development is common throughout Carlsbad,
placing homes and critical infrastructure adjacent to steep, vegetated slopes where upslope fire runs are likely and
defensible space can be difficult to maintain.
Terrain affects wildfire movement and spread. Flat areas typically result in slower fire spread, absent windy
conditions. Topographic features such as saddles, canyons, and chimneys may form unique circulation conditions
that concentrate winds and funnel or accelerate fire spread (i.e., land formations that collect and funnel heated air
upward along a slope). Many of Carlsbad’s canyons align well with the predominant Santa Ana wind direction and
are likely to increase wind speeds during extreme conditions.
Steep terrain typically results in faster upslope fire spread due to the pre-heating of uphill vegetation. Terrain may
also buffer, shelter, or redirect winds away from some areas based on canyons or formations on the landscape.
Saddles occurring at the top of drainages or ridgelines may facilitate the migration of wildfire from one canyon to
the next. Various terrain features can also influence fire behavior, as summarized in Table 4.
Table 4. Effects of Topographic Features on Fire Behavior
Topographic
Feature Effect
Narrow
Canyon
Surface winds follow canyon direction, which may differ from the prevailing wind; wind
eddies/strong upslope air movement is expected, which may cause erratic fire behavior; radiant
heat transfer between slopes facilitates spotting/ignition on the opposite canyon side.
Wide Canyon Prevailing wind direction is not significantly altered; aspect is a significant contributor to fire
behavior. Wide canyons are not as susceptible to cross-canyon spotting except in high winds.
Box Canyon/
Chute
Air is drawn in from the canyon bottom, resulting in strong upslope drafts. No gaps or
prominent saddles to let heated air escape. Fires starting at the canyon bottom can rapidly
move upslope due to chimney-like preheating of the higher-level fuels and upslope winds.
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Table 4. Effects of Topographic Features on Fire Behavior
Topographic
Feature Effect
Ridge Fires may change direction when reaching the ridge/canyon edge; strong airflows are likely at
ridge point; possibility for different wind directions on different sides of the ridge. Ridges
experience more wind. Fires gain speed and intensity moving toward a ridge. Fires burning at a
ridge can exhibit erratic behavior. Strong air flows can cause fire to whirl. Wind crossing a ridge
usually has a leeward eddy where the wind rolls around and comes up the leeward side.
Saddle Potential for rapid rates of fire spread; fires pushed through saddles faster during upslope
runs. Winds can increase when blowing through saddles due to the funneling effect of the
constricted pass. On the other side, winds will slow, but erratic winds potentially occur at the
saddle due to eddies.
Sources: Teie 1994; NFPA 2011.
3.3 Vegetation and Fuels
Vegetation types (fuels) present in the Plan Area and their contribution to fire hazards are summarized in this
section. Hazardous fuels include live and dead vegetation that exists in a condition that readily ignites, transmits
fire to adjacent structures or ground surface or overstory vegetation, and/or can support extreme fire behavior.
In many areas of Carlsbad, natural vegetation exists near structures, often less than 60 feet from homes and other
buildings. This close interface between wildland and urban development increases the risk of wildfire ignition and
spread. Invasive annual grasses are especially common near development edges, where they create continuous,
fine fuels that are highly receptive to embers. These grasses can dry quickly during the fire season, providing a
readily ignitable pathway for flames to reach structures and facilitating rapid fire spread across neighborhoods.
Fuel modification areas within Carlsbad are highly variable in condition. While some are well-maintained and provide
effective buffers against fire, others require significant maintenance to reduce hazardous fuels. Limited fuel
reduction efforts in areas adjacent to HMP open space areas present a heightened wildfire hazard, as these areas
often retain dense vegetation and other combustible materials near structures. Without consistent management,
these conditions create hazardous vegetative conditions where wildfire may cause loss and damage to communities
and other facilities and infrastructure.
Priority recommendations related to vegetation management are provided in Section 8.1 Vegetation Management.
3.3.1 Vegetative Fire Hazard
While all vegetation burns, some plants exhibit characteristics that make them more flammable than others.
Flammability can be defined as a combination of ignitability, combustibility, and sustainability. Ignitability is the ease
or delay of ignition, combustibility is the rapidity with which a fire burns, and sustainability is a measure of how well a
fire continues to burn with or without an external heat source (White and Zipperer 2010). Flammability is influenced
by several factors that can be classified into two groups: physical structure (e.g., branch size, leaf size, leaf shape,
surface-to-volume ratio, retention of dead material) and physiological elements (e.g., volatile oils, resins, and moisture
content) (Moritz and Svihra 1998; UCCE 2016; UCFPL 1997; White and Zipperer 2010). Plants that are less flammable
have low surface-to-volume ratios, high moisture contents, and minimal dead material or debris. Examples of such
plants include agave, oleander, and olive trees. More flammable species have high surface-to-volume ratios, exhibit
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low moisture contents, contain volatile oils, and have high levels of dead material or debris (Moritz and Svihra 1998;
UCFPL 1997; UCCE 2016; White and Zipperer 2010). Examples of such plants include pampas grass, juniper, and
pine. Ornamental plants can also be highly flammable and may include common species such as acacia, oleander,
lavender, rosemary, California lilac, bottlebrush, bougainvillea, and wisteria, among others.
Plant condition and maintenance are also important factors in flammability potential. Some plants that have more
flammable characteristics can become less flammable if well maintained and irrigated. Conversely, plants can be
explosively flammable when poorly maintained, or situated on south-facing slopes, in windy areas, or in poor soils
(Moritz and Svihra 1998).
Age of fuels can also affect their vegetative fire hazard. In general, chaparral 30 years and older and sage scrub 15
years and older present greater hazard due to accumulation of dead material within shrub canopies. Fires in these
older fuels tend to burn hotter and spread faster compared to fires burning in younger fuels.
Insects, fungi, other microbes, and vertebrates are a natural component of California native plant communities.
Populations of pests are dynamic and fluctuate in response to climatic and environmental changes such as drought,
stand density, fire, and other site disturbances. Healthy, vigorous plants are typically able to withstand pest attacks
when pest populations are at low to moderate levels. When stressors exist (e.g., overstocking, shading, drought),
plant vigor is reduced, and susceptibility to pest attacks and infestations increases.
In San Diego County, vegetation is affected by several regionally documented pests and stressors that increase
plant mortality and wildfire hazard. Invasive shothole borers (Euwallacea spp.) and the associated fungal disease
Fusarium dieback have caused widespread decline and mortality of native and ornamental tree species throughout
Southern California, including riparian and urban forest settings (Corella et al. 2020). Goldspotted oak borer (Agrilus
auroguttatus) has also been documented within San Diego County and is a significant stressor to coast live oak
(Quercus agrifolia) populations, contributing to oak mortality and increased dead woody fuels. In eucalyptus-
dominated landscapes, the eucalyptus longhorned borer (Phoracantha semipunctata and P. recurva) has been
established in San Diego County and is known to target water-stressed trees by disrupting cambial tissue, further
increasing surface and ladder fuel loads.
3.3.1.1 Vegetation Types
Carlsbad consists of a diverse mosaic of vegetation communities that can have a strong influence on wildfire
behavior. Native plant communities dominate much of Carlsbad’s preserved open space network, which makes up
roughly 36% of Carlsbad’s total land area. These habitats include coastal sage scrub, mixed chaparral, grasslands,
riparian corridors, oak woodlands, and eucalyptus groves, each of which presents unique fuel characteristics and
fire behavior potential. Portions of the Plan Area have been mapped as urban land cover. Urban land cover typically
represents noncombustible material (e.g., pavement) or developed and maintained landscapes (e.g., buildings,
turf), although some areas may be disturbed lands characterized by annual or perennial grass cover. Ornamental
landscape vegetation also characterizes portions of areas mapped as urban land cover. Such vegetation is a
combination of native and introduced ground cover with grass, shrub, and tree species. Some ornamental
vegetation may increase fire hazards in the WUI due to plant composition and structure (as described above) and
the lack of irrigation and maintenance. Table 5 summarizes the different vegetation types identified and mapped
in the Plan Area, and Figure 3 presents the distribution of vegetation types in the Plan Area.
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Table 5. Vegetation Types in the Plan Area
Vegetation Type Acres Percent Cover
Disturbed or Developed Areas 16,608 66%
Coastal Sage Scrub 2,594 10%
Riparian and Bottomland Habitat 1,547 6%
Scrub and Chaparral 1,533 6%
Herbaceous 1,290 5%
Agriculture 645 3%
Bog and Marsh 496 2%
Woodland 314 1%
Source: SANDAG 2021
The following sections describe the existing vegetation types present in the Plan Area and their associated
contribution to fire hazards.
3.3.1.1.1 Herbaceous Dominated
Herbaceous-dominated fuels in the Plan Area are represented by annual native and non-native grasslands (7.6%
of Plan Area), see Table 5, Vegetation Types in Plan Area. Native grasslands are characterized by perennial bunch
grasses, such as needlegrasses (Nassella spp.), as well as other herbaceous annual and perennial species. These
vegetation types support a wide range of plants and animals by providing open space for foraging, nesting, and
movement, and they often serve as transitional areas between other habitat types. Non-native annual grasses are
most prevalent and include species such as wild oats and brome.
Grassland areas in the Plan Area may include scattered or widely spaced shrubs and trees, though herbaceous
cover remains dominant. These grasses function as fine fuels with low overall fuel loads and loose fuel structure.
Due to their high surface-area-to-volume ratio, grasses dry and cure rapidly, typically beginning in late spring and
early summer, resulting in increased ignition potential early in the fire season. As a result, grasslands are associated
with frequent ignitions and rapid rates of fire spread, particularly during Santa Ana wind events. Fires in grass-
dominated fuels generally produce lower flame lengths and heat output than shrub- or tree-dominated fuels;
however, despite the low heat transfer and flame lengths, these fuels can move quickly across the landscape.
In the Plan Area, grasslands often serve as connective fuels, facilitating fire spread into adjacent shrublands or
developed areas. Where grasses occur beneath shrubs or trees, they can also contribute to surface-to-crown fire
transition by providing a continuous fine-fuel layer at the base of woody vegetation. Grasses often function as a
catalyst to more severe fire behavior in other fuel types by contributing to their ignitability.
Many herbaceous vegetation communities within Carlsbad harbor black mustard which can quickly take over
grasslands. Black mustard is an annual herbaceous plant that can grow up to 6 feet tall. In coastal grasslands,
dense stands of black mustard outcompete native vegetation. The California Invasive Plant Council ranks black
mustard as a plant with “moderate invasiveness”. Many mustard species develop a large and persistent seedbank
and deeply buried seeds of black mustard can survive for 50 years or more. Seeds on the soil during a grassland
fire are not likely to be killed by the heat of the burn. Black mustard is adapted to periodic fires, and newly burned
sites are subject to invasion. Their high biomass contributes to increased fuel load and fire frequency (DiTomaso
and Kyser 2013b). Wildfire behavior in black mustard is typically of high severity due to increased fuel height and
fuel loading compared to annual and perennial grasses.
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3.3.1.1.2 Shrub Dominated
Shrub-dominated fuels in the Plan Area
are represented by chaparral and coastal
scrub vegetation types. These shrub
vegetation types dominate the Plan
Area’s undeveloped lands, with coastal
sage scrub covering 16% of Carlsbad.
Both coastal scrub and chaparral
vegetation types may include scattered
and widely spaced trees, small patches
of grass/herbaceous vegetation, or
grass/herbaceous vegetation occurring
beneath shrub canopies, although
shrubs are the dominant cover.
3.3.1.1.3 Coastal Scrub
Coastal scrub is found throughout the
central and eastern portions of the City
and forming extensive habitat patches
within the City’s HMP Preserve System.1
Coastal sage scrub consists of maritime
succulent scrub, Diegan coastal sage
scrub, and coastal sage scrub-chaparral scrub, and collectively accounts for 2,594 acres within Carlsbad. These
habitats are commonly distributed on south- and west-facing slopes, rolling hills, and canyon systems. They are
frequently intermixed with grasslands, chaparral, and riparian habitats, particularly in vegetative areas surrounding
Agua Hedionda Lagoon, Lake Calavera, Calavera Hills, and La Costa Ridge.
Coastal scrub is considered a moderately fine fuel that is loosely compacted with a moderate fuel load. Coastal
scrub has a high surface-area-to-volume ratio, requiring less heat to remove fuel moisture and raise the fuel to
ignition temperature. It is subject to early seasonal drying in the late spring and early summer but does not fully
cure in the way that grasses do. Compared to chaparral, coastal scrub tends to have a lower content of volatile
organic compounds. The live fuel moisture content reaches its low point in the late summer and early fall. Dead
fuels consist mainly of 1-hour and 10-hour fuel sizes, or twigs and small stems ranging from 0.25 inches to 1 inch
in diameter. Under dry and windy conditions, coastal scrub has the potential for rapid ignition, high rates of spread,
and extreme fire behavior.
1 The City’s HMP Preserve System consists of roughly 6,500 acres of interconnected native habitat preserves and wildlife movement
corridors that act as permanently protected open space to conserve sensitive habitats and species across Carlsbad and regionally.
Exhibit 4. Open space area dominated by a mix of sage scrub and
mature chaparral with patches of annual grass near
Poinsettia/Alicante and Alga Norte.
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Coastal scrub is mainly composed of soft-leaved shrubs and subshrubs with flexible, woody stems. Leaves are often
summer-deciduous and high in volatile oils. Coastal scrub varies from relatively open to closed stands often with a
well-developed herbaceous understory (Syphard et al. 2006). It burns in stand-replacing fires that burn hundreds
to sometimes thousands of acres in a single event (USFS 2005). Coastal scrub species can often persist under fire
frequencies that eliminate chaparral, and they may replace chaparral at fire-return intervals of 5 to 10 years. Some
researchers also believe that high fire frequencies in coastal areas, in addition to grazing, have expanded the
distribution of coastal sage scrub. One ecological advantage the coastal scrub species have over chaparral is that
they mature early and continually recruit between fires. They also have relatively higher probabilities of
establishment on their preferred land types (coastal areas and interior valleys) and can resprout with varying
success after fire. Despite greater resilience to repeated fire, there is evidence that coastal scrub may also decline
and convert to grasslands when the fire frequency becomes extremely high (Syphard et al. 2006).
As discussed in Section 3.3.1, coastal scrub that is around 15 years or older presents an elevated wildfire hazard
due to the accumulation of dead material within shrub canopies and increased horizontal fuel continuity. While
there are no publicly available datasets that directly map coastal sage scrub age classes within Carlsbad, analysis
of historical fire perimeters indicates that large portions of the eastern coastal sage scrub areas have not burned
since the 1996 Harmony Fire. Therefore, it can be safely assumed that much of the existing coastal sage scrub in
these areas is likely to be older than 15 years, in a mid- to late-successional condition.
As provided below in Exhibits 5-6, substantial fuel accumulation in coastal sage scrub and chaparral habitats has
occurred in recent decades due to maturing vegetation and a lack of natural disturbances or fuels management
activities. This buildup increases wildfire hazards by creating higher fuel loads and greater vertical and horizontal
continuity, allowing fires to ignite more easily, burn more intensely, and spread more rapidly. As a result, risks to
structures, infrastructure, and public safety are significantly elevated, particularly in areas where dense vegetation
is located near developed communities.
Exhibit 5. Photo Taken 2011 showing moderate-low load coastal scrub
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3.3.1.1.4 Chaparral
Chaparral is found primarily in the inland and eastern portions of the City, where steeper slopes and less-developed
open space support southern mixed chaparral, chamise chaparral, and southern maritime chaparral communities.
These communities are distributed in a patchy pattern across north and west-facing slopes and frequently
intergrade with coastal sage scrub, grasslands, and oak woodlands. Chaparral is considered a moderately fine fuel
that is loosely compacted and has a moderate to high fuel load, depending on age. Chaparral has a high surface-
area-to-volume ratio, requiring less heat to remove fuel moisture and raise the fuel to ignition temperature.
Chaparral is subject to early seasonal drying in the late spring and early summer but does not fully cure in the way
that grasses do. Chaparral habitats have the potential for a high rate of spread, rapid ignition, and extreme fire
behavior given its high content of volatile organic compounds.
Fire regime of chaparral communities is mostly stand-replacing crown fires. Fire frequency interval is moderate and
ranges depending on the dominany species. Fire return intervals can range from 33 to 125 years (Fire Effects
Information System n.d.). Mature chaparral stands are more flammable compared to younger chaparral stands.
Older chaparral stands are more flammable due to their ability to accumulate more dead material. As noted in
Section 3.3.1, chaparral stands that are approximately 30 years or older present an elevated wildfire hazard due
to increased dead fuel accumulation within shrub canopies and greater horizontal and vertical fuel continuity.
Historical fire perimeter analysis indicates that much of the chaparral-dominated areas, particularly in the eastern
portions of Carlsbad, have not burned in several decades and are therefore likely in a mature, mid- to late-
successional condition with elevated fuel loading and fire intensity potential.
Exhibit 6. Photo Taken 2025 showing substantial increase in fuel loading
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3.3.1.1.5 Tree Dominated
Tree-dominated fuels within the Plan Area are
primarily composed of riparian scrub, woodland,
and forest. Smaller areas of eucalyptus stands
and coastal oak woodland are also present. Tree-
dominated types may include scattered shrubs or
shrub groupings, as well as patches of grass or
other herbaceous vegetation occurring beneath
canopies; however, trees remain the dominant
cover component.
3.3.1.1.6 Riparian Scrub, Woodland, Forest
In Carlsbad, riparian areas occur primarily along
creeks, drainages, and lagoons, including
systems such as Buena Vista Creek, Agua
Hedionda Creek, and associated lagoon
complexes. These areas support a high diversity
of plant and wildlife species, including many
sensitive and listed species, and serve as critical
wildlife movement corridors that connect larger
habitat areas. Because much of the surrounding
landscape is urbanized or fragmented, riparian
zones function as core biological resources within
the City’s HMP Preserve System.
In Carlsbad’s coastal and inland settings, riparian areas often exhibit different wildfire behavior than surrounding
upland vegetation, such as chaparral and grasslands. Under typical conditions, riparian corridors tend to maintain
higher soil moisture, cooler microclimates, and shaded fuel beds, which generally result in lower fire intensity and
slower rates of spread compared to adjacent upland habitats (Pettit and Naiman 2007). As a result, riparian zones
may function as natural fire buffers or refugia for fire-sensitive species by limiting fire spread and severity (Pettit
and Naiman 2007). However, under prolonged dry conditions or when dead and down fuels accumulate, riparian
areas may lose this buffering capacity and instead act as conduits for fire movement. Fires entering riparian zones
can additionally create canopy openings and drier microclimates that promote increased fuel accumulation,
establishment of fire-adapted species, and a higher likelihood of subsequent fires.
Exhibit 7. Open space area south of La Costa Canyon High School
dominated by a mix of mature chaparral and coastal sage scrub with
patches of annual grasses
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3.3.1.1.7 Eucalyptus
Eucalyptus woodland in the Plan Area is
a non-native vegetation community
dominated by various planted species of
eucalyptus (Eucalyptus spp.). They act
primarily as remnant groves or linear stands
associated with historic plantings, former
agricultural uses, and landscape features
such as roadways and drainage corridors.
According to the HMP, eucalyptus
woodland habitat makes up 258 acres
(1.1%) of Carlsbad’s land area; however,
isolated grouping and individual trees are
common throughout development area.
In Carlsbad, notable eucalyptus
woodlands include extensive groves
such as Hosp Grove, where mature
eucalyptus trees were historically
planted for railroad timber production
and now persist as large, contiguous
stands within the City’s trail and open space system, particularly in the vicinity of Buena Vista Lagoon. Other
prominent areas of eucalyptus groves include throughout the Aviara Golf Club and surrounding neighborhoods just
north of the Batiquitos Lagoon, interspersed throughout open space areas and neighborhoods east of El Camino
Real and west of Tamarack Ave streets, and throughout The Crossings at Carlsbad golf course, among other areas.
Eucalyptus stands are composed of fuel structures ranging from fine to heavy and may include an understory of
grass; brush; eucalyptus seedlings, saplings, and small trees; and eucalyptus leaf, twig, branch, and bark litter.
Eucalyptus litter is generally moderately compacted with heavy to very heavy fuel loads; fuel loads in eucalyptus
stands can reach between 45 and 100 tons per acre (Agee et. Al. 1973). Fuel buildup in eucalyptus stands is very
rapid, exceeding that of other tree species, and its litter (dead leaves and debris) is especially flammable (Agee et.
Al. 1973; NPS 2006; Wolf and DiTomaso 2016). Fuel reduction programs in eucalyptus stands are typically
recommended to maintain low fuel load levels (USFS 2022c).
The leaves of eucalyptus may be moderately resistant to combustion under some circumstances (Dickinson and
Kirkpatrick 1985); however, these trees are considered highly flammable because the bark catches fire readily,
and deciduous bark streamers and lichen epiphytes tend to carry fire into the canopy, which tends to produce
embers that can be carried by strong winds. These flying embers are carried downwind and result in the
development of spot fires that ignite in receptive fuel beds in advance of the fire’s leading edge (Ashton 1981;
USFS 2022c). Peeling bark is typical of many eucalyptus species and contributes to ground-based fuels (litter) when
it falls. Peeling bark is also retained for a period of time on tree trunks, where it can facilitate ground to canopy fire
transition (ladder fuel). Eucalyptus litter has a moderate surface-area-to-volume ratio, requiring moderate heat to
remove fuel moisture and raise the fuel to ignition temperature. Eucalyptus litter is subject to seasonal drying in
Exhibit 8. Hosp Grove Park is adjacent to Monroe Street in the
Carlsbad Village area.
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the late summer and fall, but fog drip, solar shading, and windbreaks provided by the eucalyptus canopy can sustain
high fuel moisture content in the summer when fog is present.
Like chaparral, eucalyptus also has a higher content of volatile organic compounds. Eucalyptus leaves produce a
volatile (Gabbert 2014), highly combustible oil, and flammable gasses may be released from trees at very high
temperatures, further increasing fire hazards (Gross 2013). The live fuel moisture content reaches its low point in
the late summer and early fall. Features that promote fire spread include heavy litterfall, flammable oils in the
foliage, and open crowns bearing pendulous (i.e., downward hanging) branches, which encourage maximum updraft
(USFS 2022c). Given average weather conditions and terrain, eucalyptus has the potential for a high rate of spread,
torching and crown fire, and extreme fire behavior.
3.3.1.1.8 Ornamental Vegetation
Ornamental vegetation is not comprehensively detailed in vegetation mapping data; however it represents a
substantial component of vegetative fuels within developed areas and the WUI.
From a wildfire hazard perspective, ornamental vegetation can present elevated risk due to its ignitability, proximity
to structures, and common use in dense or continuous plantings. Ornamental plants are often installed adjacent
to one another, such as hedges, screens, or foundation plantings, resulting in increased horizontal and vertical fuel
continuity (Ganteaume 2020a). Flammability varies widely among ornamental species depending on factors such
as moisture content, plant structure, maintenance, and the presence of volatile oils; however, many commonly used
ornamental shrubs (such as acacia) are more conducive to fire spread than native vegetation. Research indicates
that hedges in particular can act as primary fire carriers in WUI environments, rapidly transmitting fire toward
structures and contributing to structure-to-structure fire spread (Ganteaume 2020a; Graziani et al. 2022).
Wildfire events in other Mediterranean-climate regions illustrate the role ornamental vegetation can play in urban
fire behavior. During the 2016 Rognac Fire northeast of Marseille, France, fire spread within WUI neighborhoods
was largely driven by the ignition and burning of ornamental landscaping rather than native vegetation, highlighting
the importance of managing landscaped fuels in developed areas (Ganteaume 2020b). This was also observed
during the 2025 Los Angeles wildfires when ornamental vegetation was found to be a major facilitator of wildfire
spread and home loss.
The wildfire risk associated with ornamental vegetation is most pronounced within the Home Ignition Zone (HIZ).
The HIZ, sometimes referred to as the ember-resistant zone or Zone 0, describes the immediate area around a
structure, including the structure itself and nearby landscaping that can influence how easily a home can ignite
during a wildfire. Characteristics of vegetation within the HIZ, such as plant spacing, maintenance, and flammability,
are critical determinants of a home’s ignition potential (Western Fire Chiefs Association 2022). Ornamental
vegetation within this zone plays a central role in ember capture and ignition pathways, particularly in wind-driven
fire events. Within Carlsbad, defensible space requirements and fuel modification zones (FMZs) are the primary
mechanisms for reducing fire spread from ornamental vegetation to structures and adjacent to natural areas.
Proper plant selection, spacing, and long-term maintenance within defensible space and FMZs are essential for
limiting fuel continuity, reducing ember ignition potential, and improving structural survivability. Carlsbad’s current
FMZ requirements and fire-safe landscaping standards are described in greater detail in Section 2.4.2.
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3.3.2 Vegetation Management to Mitigate Wildfire Hazard
and Risk
Vegetation management is a key strategy for reducing wildfire risk within Carlsbad. Because all vegetation will burn
under the right conditions (Reinhardt et al. 2008), the objective is not to eliminate vegetation, but to moderate
potential fire behavior near communities and critical infrastructure by reducing fuel loads and adjusting the
structure, composition, and spacing (both horizontal and vertical) of retained vegetation.
Different vegetation management treatments (e.g., fuel breaks, shaded fuel breaks, defensible space zones) and
techniques (e.g., grazing, manual thinning) are applied to achieve site-specific objectives, which vary based on
vegetation type, structure, condition, and regulatory limitations. Vegetation management projects identified in this
WHRA are expected to be refined during later stages of project planning throughout the implementation of the
CWPP, when detailed management prescriptions and treatment boundaries will be defined. The following sections
describe vegetation management types, recommended treatment standards, and techniques that may be used to
implement the vegetation management projects outlined in this CWPP.
3.3.2.1 Vegetation Treatment Types
3.3.2.1.1 Wildland-Urban Interface Fuels Reduction
The WUI is the geographic area where wildlands and development intersect or intermix, presenting significant fire
risk and a complex fire environment. When wildfires occur in WUI areas, firefighting and emergency response efforts
are primarily focused on protecting human life and property. WUI fuel reduction consists of strategic reduction and
removal of vegetation to reduce fuel loads around structures, critical facilities, and roadways with the intent of
slowing the spread of wildfire between structures and wildlands and reducing wildfire intensity and structure
exposure to radiant heat. WUI fuel reduction treatments also provide emergency access points and staging areas
for firefighters and equipment and reduce flammable vegetation near emergency evacuation routes. Additionally,
WUI fuel reduction treatments may serve to enhance habitat quality in areas where existing habitat is degraded,
such as by removing invasive plant species (additional treatments that improve habitat quality are discussed below
in the Ecological Restoration subsection).
WUI fuel reduction treatments for the Plan Area are anticipated to occur within the space between structures and
wildlands or other areas of natural vegetation. The size of the treatment area (distance from structure) should be
dictated by the most currently applicable codes and standards in place for the adjacent structures (California
Government Code § 51182). Vegetation management occurring outside of WUI areas, as defined, would be
categorized as wildland fuel reduction or ecological restoration (discussed below).
Defensible space is most effective when it is implemented consistently across all properties within a neighborhood.
Wildfire does not recognize property boundaries, and gaps in vegetation management can create weak points where
embers ignite fuels or fire can spread between homes. When every property maintains required defensible space
zones by reducing flammable vegetation near structures, spacing trees and shrubs appropriately, and maintaining
clear areas around structures, the result is a continuous buffer that slows fire spread, reduces radiant heat, and
increases the effectiveness of firefighting operations.
Neighborhood-wide compliance also reduces the risk of structure-to-structure ignition, which is a primary driver of
loss in wildland-urban interface fires. In contrast, if even one parcel remains overgrown or unmanaged, it can serve
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as a pathway for fire to spread, compromising the protection efforts of surrounding compliant properties. This is
especially important during wind-driven wildfire events which can increase the potential for structure conflagrations
to destroy entire neighborhoods. A coordinated, community-level approach to defensible space therefore provides
exponentially greater protection than isolated efforts, enhancing the overall resilience of the entire neighborhood.
Current levels of vegetation management within the City are insufficient to effectively reduce wildfire risk or prevent
structure losses during wildfire events. The City’s existing 60-foot fuel modification standard is inconsistent with
state minimum requirements for 100-foot defensible space zones. In addition, numerous areas of the City provide
little to no separation between developed communities and adjacent wildland vegetation, creating hazardous
conditions that increase the potential for structure ignition.
Furthermore, fuels reduction activities within conserved HMP areas have not been implemented, contributing to
elevated wildfire risk where development directly abuts these conserved lands. The absence of a formal inspection
and enforcement program further limits compliance with defensible space requirements and reduces the
effectiveness of existing wildfire hazard mitigation standards.
Wildland Fuels Reduction
The primary goal of wildland fuel reduction in Southern California ecosystems is to decrease the ignition potential,
intensity, and spread of wildfire while maintaining or enhancing the ecological health of native plant communities.
Fuels reduction efforts in wildland areas aim to create conditions that support safer wildfire suppression operations,
decrease wildfire intensity, and spread rates, and reduce ember production and subsequent spot fire ignitions.
Wildland fuel reduction techniques and goals are highly dependent on the dominant vegetation type in the
treatment area.
▪ In grasslands, the objective is to manage fine, flashy fuels that can carry fire rapidly under dry and windy
conditions. Treatments such as targeted grazing or mowing are used to lower fuel heights and continuity,
reducing ignition potential and fire spread rates. In grass-dominated vegetation types, management is
intended to reduce vegetation height (e.g., mowing, grazing), resulting in a shorter and more compact
surface fuel layer that is less ignitable and less likely to sustain fire spread. Implemented beneath shrub or
tree canopies, such treatments also minimize the potential for a surface to crown fire transition.
Management is also intended to maintain low fuel volumes in the areas between shrub- and tree-dominated
vegetation types.
▪ In shrublands, (such as chaparral and coastal sage scrub), the goal is to remove flashy fuels, modify fuel
continuity and density to limit the rate of fire spread and flame lengths near developed areas, while
retaining sufficient native cover to prevent erosion and promote habitat stability. In shrub-dominated
vegetation types, management is intended to reduce surface fuel loading and flame lengths and slow fire
spread by increasing the horizontal spacing between retained shrubs. In areas beneath trees, management
is also intended to increase the vertical spacing between shrub and tree canopies to reduce the potential
for a surface to crown fire transition. Removal or treatment (e.g., chipping) of dead material from shrub-
dominated types also reduces dead fuel loads, can assist in reaching spacing standards, and helps
minimize the growth of highly ignitable grass/herbaceous vegetation. In shrub-grass vegetation
communities, treatments often aim to retain native shrub species while reducing herbaceous and non-
native fuel loads.
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▪ In tree-dominated landscapes, fuel reduction focuses on removing accumulated surface and ladder fuels
beneath the canopy, reducing the risk of crown fire, and maintaining the health and regeneration of mature
oak trees.
Strategic Fuel Breaks
Strategic fuel breaks are typically wide strips of land where vegetation management has taken place so that
wildfires burning into them can be more easily controlled. Fuel breaks are not intended to stop fire spread, especially
where embers can be transported via intense winds over the fuel break, but rather to modify fire behavior and
enhance firefighting capabilities. Fuel breaks are intended to reduce fire intensity, slow fire progression rates,
reduce flame lengths, minimize the likelihood of crown fire transition, increase fireline construction rates, and
provide points of access for fire crews. Fuel breaks increase the horizontal spacing between retained vegetation,
increase the vertical separation between surface fuels and overstory tree canopies, and modify surface fuels
(grasses, shrubs, debris) to reduce fire intensity and flame lengths. Fuel breaks can vary in total width depending
on terrain, vegetation, and proximity to developed uses and may reach up to 300 feet wide (CAL FIRE 2019). Fuel
breaks in shrub-dominated vegetation types typically consist of thinning brush stands to remove dead vegetation,
decrease surface fuel loading, and provide horizontal spacing between retained shrubs or shrub groupings. Fuel
breaks in tree-dominated vegetation types (shaded fuel breaks) typically consist of ladder fuel removal (removal or
treatment of live and dead understory trees and shrubs) to provide vertical spacing between trees and tree
groupings and understory vegetation and, in some cases, selective removal of overstory trees to provide horizontal
separation between retained tree canopies.
Fuel breaks can be combined with other treatment types to increase effectiveness and should be designed
considering terrain, fuel characteristics, anticipated fire behavior, and local weather conditions. The useful life of a
shaded fuel break is the estimated amount of time (in years) that the mitigation action will be effective and is based
on several factors, including vegetation type, treatment location, and weather conditions. In general, fuel breaks in
grasslands have a lower useful life (1 year), those in brush-dominated areas have a moderate useful life (2 to
4 years), and those in forested areas have a longer useful life (3 to 20 years). Maintenance of fuel breaks over time
is necessary to maintain their utility in reducing fire hazards.
Open Space Fuels Reduction
Unlike strategic fuel breaks, which are linear features, fuel reduction in larger tracts of open space is intended to
reduce fuel loads across a broader area and therefore result in lower vegetative hazard. In grass and grass-shrub
open spaces common to Southern California, fuel reduction typically involves a combination of mowing, targeted
grazing, prescribed burning, and selective herbicide application to maintain low-growing, discontinuous vegetation.
These treatments are often timed seasonally in late spring or prior to the onset of summer to limit the accumulation
of cured fine fuels that can carry fast-moving wildfires.
Targeted grazing, using sheep or goats, is a common and effective method for maintaining reduced fuel loads in
expansive grasslands and mixed grass-shrub habitats. Grazing can create a patchy vegetation structure that
disrupts fuel continuity, particularly when combined with other treatments such as mowing or selective shrub
thinning. Grazing is often favored in areas with limited equipment access or where mechanical treatment could
cause soil disturbance or erosion.
Routine maintenance and adaptive management are critical to the long-term effectiveness of these treatments.
Because fine fuels in Southern California ecosystems can regrow rapidly following seasonal rains, ongoing
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monitoring and periodic re-treatment are necessary to sustain reduced fuel conditions and limit wildfire intensity
across the landscape. In addition, fuel management treatments in open space areas should also be designed and
implemented in a manner that does not promote the establishment or spread of invasive plant species. Disturbance
caused by mechanical treatments, grazing, or fire can create conditions favorable to invasive annual grasses and
forbs, which can increase fine fuel continuity and fire frequency. To avoid these outcomes, treatments should
incorporate best management practices to avoid the considerable establishment of high hazard invasive species.
Ecological Restoration
Ecological restoration treatments focus on restoring ecosystem processes, conditions, habitat value, and wildfire
resiliency by modifying uncharacteristic fuel conditions (Fuller et al. 2020). Such fuel conditions could exist for
various reasons, including a history of fire exclusion; occurrence of severe wildfire events; conversion of vegetation
community types; displacement of native plant communities by invasive species; increased plant mortality due to
pest or disease infestations; or other influences that contribute to deviation from historical landscape conditions,
such as climate change, land use conversions, and other indirect effects (Lenihan et al. 2008). Ecological
restoration treatments would involve management actions intended to return the treatment area to more natural
conditions. Wildfire is a natural occurrence in many California ecosystems and has played a significant role in
shaping the landscape and maintaining ecosystem processes (Pausas et al. 2004). Ecological restoration
treatments can contribute to improving overall ecosystem health by increasing plant vigor, reducing susceptibility
to pests and disease, increasing tolerance to drought and climate change effects, and reducing the threat of high-
severity wildfire. Healthy ecosystems have a mosaic of successional stages, providing a diversity of wildlife habitats,
and are composed of vegetation that is more resistant to pest and disease outbreaks.
Potential ecological restoration treatments in the Plan Area may include invasive species control or removal,
treatments focused on managing type conversion of vegetation communities, treatments to mimic natural
disturbances to control species encroachment and alter vegetation community successional stages, prescribed
burning to mimic natural fire recurrence, prescribed burning to treat thatch buildup in grasslands, post-fire hazard
tree removal, treatment of pest or disease-infected vegetation, and treating ladder fuels or thinning forest stands
to reduce fuel loads and return woodlands/forests to historical compositions. In addition, these projects may
include the removal of non-native flammable tree species and replacing these trees with more fire-resistant species
(e.g., coast live oak, California sycamore, willows, etc.)
3.4 Wildfire Types and Potential Fire Behavior
Wildfire behavior is a complex interaction of environmental conditions, fuel characteristics, and topography.
Understanding how fires ignite, spread, and intensify is critical for effective wildfire planning, mitigation, and
suppression. The following sections summarize the primary wildfire types, the mechanisms that influence fire
behavior, and the key fire characteristics that inform risk assessment and firefighting strategies.
Several wildfire types exist, as summarized below.
▪ Surface Fire: A surface burning fire with low flame lengths (usually < 1 meter) that burns loose debris on
the surface, which includes dead branches, leaves, and low vegetation (NWCG 2024).
▪ Crown Fire: A fire that advances from top to top of trees or shrubs more or less independent of a surface
fire. Crown fires are sometimes classed as running or dependent to distinguish the degree of independence
from the surface fire (NWCG 2024).
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Another component of fire behavior is
spotting—the transfer of firebrands
(embers) ahead of a fire front—which can
ignite smaller vegetation fires (NWCG
2024). These smaller fires can burn
independently or merge with the primary
fire. Spotting can also result in structural
ignitions when transported embers reach
a receptive fuel bed2 (e.g., combustible
roofing), especially in wind-driven fires,
such as those occurring during Santa Ana
wind events in the foothills of the San
Gabriel mountains. Structure fires, as well
as vegetation-fueled fires, can generate
firebrands. Additionally, landscape
features like ridges can dramatically
affect fire behavior by changing prevailing
wind patterns, funneling air, and
increasing wind speeds, thereby
intensifying fire behavior.
Each of the fire types mentioned above may occur within the Plan Area, depending on site-specific conditions. Fire
behavior is how a wildland fire reacts to weather, fuels, and topography. The difficulty of controlling and suppressing
wildfire is typically determined by fire behavior characteristics, such as rate of spread, fireline intensity, torching,
crowning, spotting, fire persistence, and resistance to control. Extreme fire behavior is that which precludes methods
of direct control (e.g., flame lengths 8 feet and greater), behaves unpredictably and erratically, and typically involves
high spread rates, crowning and spotting, the presence of fire whirls, and a strong convective column.
Fire behavior characteristics are an essential component in understanding fire risk. Flame length—the length of the
flame of a spreading surface fire within the flaming front—is measured from midway in the active flaming
combustion zone to the average tip of the flames (Andrews et al. 2008). Although it is a subjective and nonscientific
measure of fire behavior, it is imperative to fireline personnel when evaluating fireline intensity and is worth
considering as a vital wildfire variable (Rothermel 1993). Fireline intensity is a measure of heat output from the
flaming front and affects the potential for a surface fire to transition to a crown fire. Table 6 presents an
interpretation of flame length and its relationship to fire suppression efforts.
Table 6. Fire Behavior Interpretation
Flame Length Fireline Intensity Interpretation
Under 4 feet Under 100 BTU/ft/s Fires can generally be attacked at the head or flanks
by persons using hand tools. Hand line should hold
the fire.
4 feet to 8 feet 100–500 BTU/ft/s Fires are too intense for a direct attack on the head by
persons using hand tools. Hand line cannot be relied
2 An area where existing vegetation or other combustible debris is in a condition that is ready and available to ignite when an ember
lands upon it.
Exhibit 9. Flames during the 2014 Poinsettia fire well exceeding
20 feet. (Source: Daily Mail Reporter, 2014)
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Table 6. Fire Behavior Interpretation
Flame Length Fireline Intensity Interpretation
on to hold the fire. Equipment such as dozers,
pumpers, and retardant aircraft can be effective.
8 feet to 11 feet 500–1,000 BTU/ft/s Fires may present serious control problems—torching
out, crowning, and spotting. Control efforts at the fire
head will probably be ineffective.
Over 11 feet Over 1,000 BTU/ft/s Crowning, spotting, and major fire runs are probable.
Control efforts at the head of fire are ineffective.
Source: Roussopoulos and Johnson 1975.
Note: BTU/ft/s = British thermal units per foot per second.
3.4.1 Wildfire History
Fire history provides valuable insight into fire frequency, seasonality, ignition causes, and areas of recurring risk.
While Carlsbad has experienced relatively few large-scale wildfires compared to inland areas of San Diego County,
nine incidents larger than 10 acres have occurred within the city limits since 1970. The most significant was the
1996 Harmony Fire, which burned over 9,300 acres primarily east of the city limits under strong Santa Ana wind
conditions, resulting in a fatality, property loss, and extensive habitat damage. The 1970 Theater Fire (1,192
acres), 1979 unnamed fire (966 acres), 1982 Assist #16 Fire (654 acres), and 1987 Assist #38 Fire (226 acres)
were all largely driven through the inland chaparral and grassland canyon areas. More recently, the 2014
Poinsettia Fire burned 600 acres within the southern portion of Carlsbad, destroying 28 structures and prompting
widespread evacuations during early-season Santa Ana winds and extreme drought conditions. This fire highlights
the greater regional shift of wind-driven fires occurring outside of the typical wildfire season. Table 7 summarizes
the nine recorded wildfires that have burned in Carlsbad since 1970 and a graphical depiction of wildfire history
within the city and surrounding lands is provided in Figure 4.
The fact that recent fires within the city limits have been relatively small does not indicate a low wildfire hazard. In
many cases, it reflects a lack of recent large fire events rather than inherently safer conditions. The absence of
periodic fire and limited fuel management has allowed vegetation to mature and accumulate, increasing fuel loads
and creating conditions for more intense and fast-moving wildfires when they do occur.
At the same time, a substantial number of homes are located immediately adjacent to small open space areas and
patches of coastal sage scrub and chaparral. These edge conditions place structures directly within the wildfire
exposure zone, where even a small ignition can quickly impact nearby neighborhoods, particularly during significant
wind events. As a result, despite a history of smaller incidents, the underlying hazard and risk to homes and public
safety remain elevated and, in some cases, are increasing over time.
It should be noted that Table 7 includes significant fires and does not provide a comprehensive list of all wildfires
within the city, as numerous smaller fires have occurred but were confined to a limited area.
Table 7. Wildfire History within the City and Surrounding Lands
Fire Name Year Month Acres
Theater 1970 September 1,192
Unnamed 1979 Unknown 966
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Table 7. Wildfire History within the City and Surrounding Lands
Fire Name Year Month Acres
Assist #16 1982 September 654
Assist #38 1987 May 226
Harmony 1996 October 9,359
Poinsettia 2014 May 600
Park Fire 2021 January 2
Boulevard Fire 2022 June 10
Claro Fire 2025 June 45
Total Acres 13,054
Source: CAL FIRE 2025, CFD
While wildfire risks are centrally present for wildfires that ignite within Carlsbad, research has suggested that wind-
driven embers, rather than direct flame contact, are often responsible for igniting homes and infrastructure well
beyond the fire’s perimeter [1]. Therefore, Carlsbad may face threats from wildfires burning in adjacent lands. This
has prompted a state-wide shift in fire mitigation strategies, focusing on fire-resistant building materials, defensible
space establishment and maintenance, and community preparedness.
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Figure 4 Wildfire History
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4 Values at Risk
Values threatened by wildfire in the Plan Area include life, property, structures, critical infrastructure, agriculture,
and natural resources. The primary objective of this WHRA is to identify recommendations and project priorities to
protect these values at risk. While safeguarding lives and property is of paramount importance, the protection of
infrastructure, agricultural resources, and natural resources is also critical. Wildfire can cause significant secondary
impacts to the community, including loss of access from closed or damaged roads; disruption of communications
when phone lines or cell towers are damaged; power outages resulting from damaged distribution lines or public
safety power shutoffs; and reduced water availability due to damaged infrastructure or loss of power to well or
system pumps. Additional impacts can include restrictions on recreation and tourism, limited or lack of access to
job sites, and reduced capacity for agricultural production and distribution. Post-fire effects are another major
concern, particularly erosion and slope failures, which have historically caused damage in the Plan Area. This
section summarizes the values threatened by wildfire in the Plan Area.
4.1 Wildland-Urban Interface
The WUI represents areas where development and wildlands intersect or intermix, creating conditions that
significantly increase wildfire risk to life, property, and critical infrastructure. In Carlsbad, WUI areas are particularly
important because they include neighborhoods adjacent to open space preserves and canyon corridors, where
dense vegetation and complex terrain can amplify fire behavior and complicate suppression efforts. When wildfire
occurs in these areas, emergency response priorities shift toward protecting human life and structures, as well as
maintaining ingress and egress (evacuation) corridors.
CAL FIRE mapped three WUI types representing the overall pattern of development in the Plan Area (CAL FIRE 2025):
▪ Wildland Urban Interface: Dense housing adjacent to vegetation that can burn in a wildfire
▪ Wildland Urban Intermix: Housing development interspersed in an area dominated by wildland vegetation
subject to wildfire
▪ Wildfire Influence Zone: Wildfire susceptible vegetation up to 1.5 miles from Wildland Urban Interface or
Wildland Urban Intermix
Carlsbad’s WUI pattern primarily includes interface zones – where development borders flammable vegetation and
a distinct urban edge can be defined. Additionally, Carlsbad includes some smaller areas of intermix zones, where
structure densities are lower, an urban edge is less defined, and structures are intermixed with native and non-
native vegetation. These conditions increase the likelihood of vegetation-to-structure fire spread and ember
intrusion, especially during Santa Ana wind events. The WUI is most prominent near Calavera Hills, La Costa Creek,
Rancho La Costa, and La Costa Ridge, as well as other canyon and ridgeline neighborhoods where evacuation
complexity and access limitations pose additional risks.
These WUI areas represent some of the highest-value assets at risk in Carlsbad, including residential
neighborhoods, evacuation routes, and adjacent open space preserves that support ecological and recreational
resources. The proximity of homes to flammable vegetation, combined with Carlsbad’s canyon-aligned terrain and
seasonal Santa Ana winds, creates conditions where fast-moving fires can infiltrate housing developments in a
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matter of hours. This highlights the importance of defensible space, vegetation management, and structural
hardening as critical strategies for reducing risk to life and property.
Note: The CWPP process allows local jurisdictions to delineate their own WUI boundaries. When the CWPP for
Carlsbad is prepared, the local WUI boundaries may be modified and refined.
4.2 Life Safety
The potential for loss of life due to wildfire is inherently difficult to quantify, as it depends on a combination of fire
behavior, weather conditions, evacuation effectiveness, and community preparedness. Within Carlsbad, the 2014
Poinsettia Fire tragically resulted in one fatality, highlighting that even relatively small fires can pose a serious threat
to life. However, the potential for much greater loss of life exists during extreme wildfire events, as demonstrated
by historic fires throughout San Diego County and across Southern California, where rapid fire spread, high flame
lengths, and widespread ember showers have overwhelmed communities.
Carlsbad’s dense suburban neighborhoods further increase this risk by creating conditions favorable to urban
conflagration, where wind-driven embers and structure-to-structure ignitions can allow fire to move quickly through
developed areas. During strong Santa Ana wind events, these conditions can be amplified, as high wind speeds
carry embers over long distances and accelerate fire spread. The combination of flammable fuels in surrounding
open space, a high density of residential structures, and limited access routes can significantly increase both the
probability and potential consequences of life-threatening fire events.
4.2.1 Structures and Population
4.2.1.1 Structures
Carlsbad’s built environment includes single-family and multi-family housing, commercial and industrial facilities,
schools, and critical infrastructure. Residential neighborhoods are largely planned and suburban, but many exist
directly adjacent to open space preserves and natural drainages, creating an extensive WUI edge where native
vegetation and ornamental landscaping are adjacent to structures.
Based on GIS mapping and field verification, there are an estimated 12,500 structures within the updated Fire
Suppression Zone Area, including residential, agricultural, industrial, and recreational buildings. In addition,
approximately 32.7% of the Plan Area falls within a VHFHSZ, 17.2% within a High FHSZ, and 7.2% within a Moderate
FHSZ. These designations highlight the elevated wildfire risk across large portions of the City, particularly in
neighborhoods adjacent to open space preserves and canyon corridors, where dense vegetation and complex
terrain can amplify fire behavior and complicate suppression efforts.
Historical events emphasize the potential for similar wildfire behavior in Carlsbad. For example, the 2007 Witch
Fire in San Diego County burned nearly 198,000 acres and destroyed more than 1,000 structures under powerful
Santa Ana wind conditions, rapidly spreading through canyons and foothill communities and forcing mass
evacuations. In certain scenarios, similar dynamics could occur within Carlsbad, where open space preserves and
canyon corridors with mature, continuous fuel beds can channel wind-driven fire into adjacent residential areas.
These conditions increase the likelihood of fast-moving, wind-driven fires impacting housing developments during
extreme weather events.
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There is also varied structural
vulnerability in Carlsbad.
Approximately 5,000 housing units
in Carlsbad are more than 50 years
old and 26,000 units are more than
30 years old (City of Carlsbad 2021).
These older homes were built before
modern ignition-resistant standards
and are therefore more vulnerable to
wildfire impacts (radiant heat
exposure, direct flame impingement,
and ember intrusion).
Beyond direct flame contact, wind-
driven embers pose a significant
ignition risk. Embers can travel long
distances during Santa Ana wind
events and ignite receptive fuel beds
such as roofs, decks, vents, and
ornamental vegetation, often
causing structure loss far beyond the
main fire front. Post-fire recovery
presents additional challenges, including contamination concerns, compliance with updated building codes, and
the financial burden of reconstruction.
The potential for structure loss from wildfire can be substantially mitigated through structure and home hardening
practices. Wildfires often ignite homes through wind-driven embers, radiant heat, and direct flame contact, making
vulnerable building components and combustible materials a primary source of structural ignition. The following
describes practices that can be implemented to greatly improve home survivability during wildfire exposure by
reducing ignition potential and increasing a structure’s resistance to ember intrusion and heat exposure.
Roof
The roof is one of the most important components because it is a large horizontal surface where embers
accumulate. Homes with Class A fire-rated roofs (e.g., composition shingles, tile, metal) are far less likely to ignite
than homes with wood shake roofs. In addition, keeping roofs free of pine needles, leaves, and other debris is
essential to prevent ember ignition.
Vents
Attic and foundation vents are a common pathway for embers to enter a structure. Once embers enter attic spaces,
they can ignite insulation or stored materials and start a fire inside the home. Installing ember- and flame-resistant
vents with fine metal mesh or specialized baffle systems greatly reduces this vulnerability.
Exhibit 10. Wildland-urban intermix development at Green Valley
Open Space
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Eaves and Soffits
Open eaves and soffits can trap heat and embers beneath the roofline. Enclosing these areas with
noncombustible or ignition-resistant materials helps prevent ember accumulation and reduces the likelihood of
ignition in the roof assembly.
Windows
Windows can fail during wildfire exposure due to radiant heat, allowing embers and flames to enter the structure.
Dual-pane tempered glass windows perform significantly better than single-pane windows because they are more
resistant to heat breakage.
Siding and Exterior Walls
The type of exterior siding influences how easily a structure ignites from radiant heat or flame contact.
Noncombustible materials such as stucco, fiber-cement board, masonry, or metal provide better protection than
untreated wood siding.
Decks, Fences, and Attached Structures
Decks, balconies, stairs, and attached fences can act as ignition points if they are constructed from combustible
materials or if vegetation and debris accumulate underneath them. Using ignition-resistant materials and
preventing fuel buildup beneath decks can significantly reduce this risk. Further, avoiding the use of wooden fences
connected to a home decreases the likelihood of structure ignition.
4.2.1.2 Population
Carlsbad has a permanent population concentrated in suburban neighborhoods, but population levels fluctuate
due to daily commuters and visitors to parks, beaches, and commercial centers. Annual visitation typically peaks
during the summer months, coinciding with the fire season. Increased population, particularly among visitors
unfamiliar with the area, creates additional challenges for wildfire response and evacuation.
In addition to these seasonal variations, some residents face heightened challenges during wildfire events,
including limited mobility, chronic health conditions, income constraints, or language barriers. Such factors can
make evacuation more difficult and limit access to emergency information and resources. Older neighborhoods,
such as Carlsbad Village, Barrio, and Old Carlsbad, tend to house lower-income residents, potentially limiting the
capacity for residents to prepare for or recover from wildfire impacts (City of Carlsbad 2021).
In a study conducted in Ventura County by Baker et al. (2022), marginalized and vulnerable communities faced
disproportionally more barriers to wildfire preparedness and understanding when it came to communications,
available resources, and inclusion in the planning process. These findings highlight the importance of targeted
outreach and inclusive strategies to ensure all residents can prepare for and respond effectively to wildfire hazards.
4.3 Critical Facilities Infrastructure
Critical infrastructure within Carlsbad includes the essential or vulnerable facilities and systems that support core
services, such as water supply, transportation, education, emergency response, energy distribution (petroleum and
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electricity), communication, and elder care facilities. The Infrastructure of Interest, as identified by the City, includes
14 elder care facilities and 44 additional facility types. Damage or disruption to these critical assets during a
wildland fire can significantly affect response operations and community safety, and in some cases may interrupt
critical services for extended periods while recovery measures are made. A total of 55 facilities were evaluated to
support preparation of this WHRA.
4.4 Natural Resources
Natural resources include biological resources, visual resources, streams and water resources, slopes and soil
stability, and air quality. According to the City’s HMP, the Plan Area consists of largely developed land on the coastal
portions of Carlsbad; however, approximately 8,758 acres (36% of Carlsbad’s total area) consists of natural
vegetation communities located in and around Carlsbad’s three coastal lagoons and within the higher-elevation,
steeper-sloped inland areas. These natural lands provide important ecological functions, open space values, and
wildlife habitat, while also representing areas where wildfire risk intersects with sensitive environmental resources
and the built environment.
Biotic Communities
The Plan Area’s vegetation (biotic)
communities provide important biological
habitats for plant and animal species. The
distribution of vegetation types in the Plan
Area is presented in Section 3.3 and Figure
3. The topographic diversity of the Plan Area
supports a wide range of species and habitat
types despite extensive urban development
in Carlsbad. This diversity is driven by
Carlsbad’s varied topography, which
includes coastal terraces, lagoons,
drainages, rolling hills, inland valleys, and
steeper-sloped upland areas.
The vegetation that exists in these
communities also becomes fuel available to
burn during a wildfire. The impact of a
wildfire in many of these communities can
be devastating, especially under extreme
wind and weather conditions.
The City’s HMP identifies environmentally sensitive habitat areas that require coordinated protection and long-term
management in cooperation with the California Department of Fish and Wildlife (CDFW) and the U.S. Fish and
Wildlife Service (Figure 5). These habitats were identified through comprehensive vegetation mapping, GIS-based
habitat sensitivity modeling, field verification, and integration with regional Natural Communities Conservation
Program (NCCP) and Multiple Habitat Conservation Program (MHCP) datasets, and are considered biologically
important due to their rarity, ecological function, and association with special-status species. Many of these
habitats, particularly coastal sage scrub, chaparral, grasslands, and riparian systems, are vulnerable to wildfire due
Exhibit 11. Mosaic open-space vegetation of coastal scrub,
annual grasses, chaparral, and riparian/woodland vegetation
at Buena Vista Creek Ecological Reserve.
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to fuel accumulation, fragmentation, and increased edge effects from surrounding development, which can alter
fire frequency and intensity beyond natural regimes and lead to habitat degradation or type conversion.
The following habitat types present in the Plan Area are considered sensitive under California regulations and policies:
▪ Native Grassland
▪ Non-Native Grassland
▪ Maritime Succulent Scrub
▪ Diegan Coastal Sage Scrub
▪ Coastal Sage Scrub-Chaparral Scrub
▪ Southern Maritime Chaparral
▪ Riparian habitats
▪ Woodland habitats
▪ Marsh habitats
Because of the diversity of biotic communities in the Plan Area, many different rare, endangered, and threatened
plant and animal species exist. A total of 43 sensitive plant and animal species were evaluated for coverage under
the HMP. A “covered species” is considered to be protected, because the fully assembled HMP preserve system
would provide sufficient habitat to sustain the species upon buildout of the city and into the future. The HMP
currently covers 31 species, with 12 others contingent on funding and other requirements. The following describes
some of the rare, endangered, or threatened wildlife species covered by the HMP, which may be adversely affected
by wildfire.
Calavera Hills/Robertson Ranch/EW Ecological Preserve
The Calavera Hills/Robertson Ranch/EW
Ecological Preserve consists of 237 acres of
conserved open space and is located in the
northeast portion of Carlsbad, near the
intersection of College Boulevard and
Carlsbad Village Drive. The preserve was
established in 2006 and is managed by the
Center for Natural Lands Management
(CNLM). CNLM is responsible for protecting
the species and habitat in perpetuity on the
preserve. The site protects a diverse
assemblage of sensitive habitats, including
coastal sage scrub, chaparral, valley foothill
riparian habitat, and native grasslands,
which support regionally important wildlife
populations. The preserve provides habitat
for multiple special-status species, including
the coastal California gnatcatcher (Polioptila
californica californica), Least Bell’s vireo
(Vireo bellii pusillus), and Thread-leaved brodiaea (Brodiaea filifolia). The CNLM actively manages the preserve
Exhibit 12. Calavera Lake Open Space
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through invasive species control, habitat restoration, and long-term stewardship to maintain ecological function
and protect sensitive species within an increasingly urbanized landscape (CNLM 2024).
Buena Vista Creek Ecological Reserve
The northern portion of the Plan Area includes the Buena Vista Creek Ecological Reserve, a 134-acre preserve
located south of State Route 78 between College Avenue and El Camino Real. The Reserve was acquired in 2007
and is owned by CDFW, with management provided by CNLM. The site protects a mosaic of sensitive habitats,
including coastal scrub, California annual and perennial grassland, valley foothill riparian forest, and southern
riparian scrub. Due to the sensitivity of the species and habitats present, public access to the Reserve is restricted
(CNLM 2024).
Rancho La Costa Preserve
Towards the eastern area of Carlsbad lies the Rancho La Costa Preserve. This is a large conservation area of
approximately 1,640 acres located within the cities of Carlsbad and San Marcos in San Diego County. The preserve
was acquired between 2001-2011 and is owned and managed by the CNLM (CNLM | Rancho La Costa). As
described in the HMP, Rancho La Costa Preserve supports extensive coastal sage scrub and mixed chaparral
communities, along with valley foothill riparian habitat, native grasslands, and a finite amount of coastal oak
woodlands. It supports multiple special-status species, including Del Mar manzanita, coastal California gnatcatcher,
San Diego thorn mint, and Thread-leaved brodiaea, and functions as an important wildlife movement corridor
connecting Batiquitos Lagoon and Lake Hodges (CNLM | Rancho La Costa).
Critical Habitat
Critical habitat, or conserved habitat, consists of specific geographic areas or habitat types that contain features
essential to the conservation of federally listed species and that may require special management or protection.
These designations provide notice to the public and private landowners regarding areas that are vital to the recovery
of listed species and may trigger additional consultation requirements when federal funding, permits, or approvals
are involved. Within Carlsbad, conserved habitat, in the form of preserve areas, have been designated for several
sensitive plant and animal species listed in the City’s HMP, including the coastal California Gnatcatcher (2,146
acres), California Least Tern (917 acres), Light-footed Clapper Rail (140 acres), Western Snowy Plover (917 acres),
Least Bell’s Vireo (498 acres), and several others in need of protection. These critical habitat areas are primarily
concentrated within Carlsbad’s coastal lagoons, riparian corridors, and interconnected upland preserve lands and
are integrated into the broader regional conservation strategy under the North County MHCP.
Environmentally Sensitive Habitat
Environmentally Sensitive Habitat Areas (ESHAs) within Carlsbad are identified and protected through the City’s
HMP, Local Coastal Program (LCP), and participation in the regional MHCP, consistent with ESHAs as defined by
the California Coastal Act. In coastal North San Diego County, including the Plan Area, ESHAs most commonly
consist of coastal lagoons, coastal and inland waterways, wetlands, riparian corridors, marshes, and sensitive
upland habitats that support special-status plant and wildlife species or function as wildlife movement corridors.
Within Carlsbad, sensitive upland habitat types include coastal sage scrub, maritime succulent scrub, southern
maritime chaparral, coastal sage–chaparral scrub, native grassland, and associated lagoon uplands, many of which
are recognized as ESHAs when they are biologically important, easily disturbed, or associated with listed sensitive
species. These habitats are mapped and managed across Carlsbad’s HMP Preserve System, including state
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ecological reserves, City-owned habitat preserves, and privately-owned conserved lands. Limitations on
development, vegetation removal, and fuel modification currently apply within ESHAs to avoid degradation of
habitat function, maintain wildlife connectivity, and ensure long-term ecological viability, while strategically applying
wildfire risk reduction treatments where consistent with habitat protection objectives.
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5 Wildfire Hazard and Risk
Assessment Methods
The wildfire hazard assessment conducted in support of this WHRA involved an evaluation of field conditions,
processing and analyzing spatial datasets in GIS, and conducting GIS-based modeling of wildfire behavior and
wildfire hazard. This assessment effort is presented in the following sections.
5.1 Plan and Data Evaluation
Dudek collected and evaluated various plans and data sets to support our evaluation of wildfire hazard and risk in
the Plan Area and to inform the wildfire risk reduction recommendations contained in this WHRA. Evaluated
mapping and data sets included wildfire and ignition history data, FHSZ mapping data, vegetation/land cover data,
terrain data, roads data, asset locations, and WUI and community area data sets. Evaluated planning documents
included the City Landscape Manual, the City’s Habitat Management Plan, the City General Plan, and fire-related
City ordinances and codes.
5.2 Field Assessment
A thorough field assessment was conducted by Dudek staff in August 2025. For portions of the field assessment,
Dudek was accompanied by representatives from CFD. The intent of the field visits was to evaluate existing fuel
load conditions, current land management practices, infrastructure types and locations, and to gain an
understanding of general fire hazard conditions throughout the Plan Area. The goal was also to identify structural
vulnerabilities and opportunities for improved defensible space protection on sites identified as Infrastructure of
Interest. Evaluated sites were comprised of 14 elder care facilities and 44 sites consisting of public safety facilities,
utilities, schools, and open space areas. During the field assessment, site conditions were noted and documented
via photographs.
5.3 Wildfire Hazard Modeling
Wildfire hazard represents the existing wildfire environment and potential wildfire behavior. A comprehensive
wildfire hazard assessment was conducted for the Plan Area using FlamMap to evaluate potential wildfire exposure,
intensity, and fire spread within Carlsbad. The analysis relied on a 10-meter resolution Landscape Base file that
included terrain characteristics (elevation, slope, aspect) and vegetation/fuel inputs (fuel model and canopy cover),
along with locally derived 90th and 97th percentile weather conditions to capture both severe summer onshore
winds and peak Santa Ana offshore wind events. This assessment incorporated three key components: flame length
modeling, burn probability analysis, and wildfire progression modeling. Flame length and burn probability were
combined into a relative wildfire hazard layer derived from wildfire intensity and probability across the landscape.
Wildfire progression modeling utilized the Minimum Travel Time (MTT) tool to simulate fire spread from selected
ignition points and lines east of the Plan Area, providing spatial representations of potential fire pathways, arrival
times, and areas of elevated exposure. Collectively, these analyses provide a landscape-scale understanding of
wildfire hazard and behavior, informing the Wildfire Hazard and Risk Assessment for the City (See Section 6.4).
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To initiate the modeling effort, a Landscape Base file was created and analyzed. The Landscape Base file consisted
of five distinct data layers representing terrain (elevation, slope, and aspect) and vegetation/fuels (fuel model
designation and canopy cover). The Landscape Base file was created at a scale of 10 meters using the data sources
presented in Table 8.
Table 8. Landscape Base File Input Data Sources
Model Input Data Source
Elevation USGS 10-m Elevation
Slope USGS 10-m Slope
Aspect USGS 10-m Aspect
Fuel Model San Diego County Vegetation Map (Vegetation_CN)3
Canopy Cover National Land Cover Database (NLCD) Tree Canopy Cover (2023)
5.3.1 Flame Length
Flame length—the length of the flame of a spreading surface fire within the flaming front—is measured from midway
in the active flaming combustion zone to the average tip of the flames (Andrews et. al. 2008). Although it is a
somewhat subjective measure of fire behavior, it is imperative to fireline personnel when evaluating fireline intensity
and is worth considering as a vital wildfire variable (Rothermel 1993). Table 6 summarizes flame length and fireline
intensity measurements and provides an interpretation related to suppression efforts.
Flame length modeling was conducted in FlamMap and utilized the landscape file inputs provided in Table 9 in
addition to custom weather parameters based on local conditions. Wildfire behavior modeling is typically conducted
during two weather scenarios to provide a comprehensive assessment of wildfire throughout fire season. This
concept is typically referred to as 90th and 97th percentile weather conditions. In fire weather forecasting and fire
behavior modeling, the terms 90th percentile and 97th percentile refer to statistically derived weather conditions
based on a historical record of observations (e.g., temperature, humidity, wind, and fuel moisture). These
percentiles are used to represent severe or extreme conditions that strongly influence fire ignition, spread, intensity,
and difficulty of suppression. They are not simple thresholds but indicate how rare and extreme the conditions are
relative to typical weather history for the same location and season.
For this WHRA, 90th percentile weather conditions are representative of worst-case summer weather with onshore
winds, while 97th percentile conditions represent peak Santa Ana conditions with rapid offshore wind speeds.
Values for 90th and 97th percentile weather were obtained from San Diego County’s Fire Protection Plan Guidelines
which set standards for conducting fire behavior analyses. Weather values were obtained from Remote Automatic
Weather Stations (RAWS) across the County and aggregated based on climate zone. Carlsbad is located within both
the Maritime and Coastal climate zones. For this analysis, the values for the Coastal climate zone were used as
they represent more conservative values for fire behavior modeling (warmer, drier). Values for 90th and 97th
percentile weather are provided below in Table 9.
3 This dataset maps vegetation communities across San Diego County and classifies vegetation type through the Holland
Classification system. This dataset was assessed for accuracy through high-resolution satellite imagery and insight from field
tours. Many areas were edited to reflect new development not accounted for in the data. Vegetation classifications were cross-
walked to Scott and Burgan fire behavior fuel models using CAL FIRE’s fuel model cross-walk framework utilized during the 2023
Fire Hazard Severity Zone mapping process.
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Table 9. Wildfire Behavior Modeling Weather Inputs
Model Input 90th Percentile Weather 97th Percentile Weather
Wind Speed* 19 mph 26 mph
Wind Direction 260 degrees 60 degrees
Wind Type Gridded Gridded
1-Hour Fuel Moisture 4% 3%
10-Hour Fuel Moisture 6% 4%
100-Hour Fuel Moisture 7% 6%
Herbaceous Fuel Moisture 60% 30%
Live Woody Fuel Moisture 90% 50%
Crown Fire Calculation Method Scott/Reinhardt Scott/Reinhardt
To identify worst-case fire behavior conditions, results from both the 90th and 97th percentile weather scenarios
were overlaid to capture the highest modeled flame lengths across a range of potential weather patterns. Although
the 97th percentile weather scenario generally produces the most extreme fire behavior due to hotter, drier, and
windier conditions, the analysis showed that in some areas the 90th percentile scenario resulted in higher flame
lengths. This occurred where steep slopes were aligned with the prevailing onshore wind direction represented in
the 90th percentile weather inputs, which can accelerate upslope fire spread and increase flame lengths. By
combining results from both scenarios, the analysis ensures that the final dataset reflects the most severe fire
behavior that could occur under differing but plausible weather conditions.
5.3.2 Burn Probability
In FlamMap, burn probability is modeled by simulating thousands of potential fires across a landscape and
calculating how often each location burns under a defined set of fuel, weather, and topographic conditions. The
model uses spatial inputs such as vegetation and terrain, along with constant (static) weather and fuel moisture
conditions. Ignitions are randomly distributed across the landscape, and each ignition is modeled using the
Minimum Travel Time (MTT) fire spread tool to simulate how fire would spread over a specified duration. As each
simulated fire spreads, the model records which pixels burn. After all simulations are complete, the number of times
each pixel burns is divided by the total number of ignitions to produce a burn probability value between 0 and 1.
These values represent the relative likelihood that a given location would burn if a fire were to occur somewhere on
the landscape under the modeled conditions, highlighting areas of greater wildfire exposure driven by fuels, terrain,
and wind patterns rather than ignition likelihood. Burn probability is related to the size of fires that occur on a given
landscape, where larger fires produce higher burn probabilities than smaller fires. The following equation
summarizes the burn probability calculation:
Burn Probability = number of times burned / total number of ignitions
Given that the Plan Area experiences both extreme offshore winds and typical summer onshore winds, the burn
probability output represents a weighted average of burn probabilities modeled under each of these weather
conditions (See Table 9). Similar to flame length modeling, gridded winds were used to model fire spread and burn
probability, which utilizes the WindNinja program embedded in FlamMap. Gridded winds alter wind flow across the
landscape based on topographic effect (e.g., drag effect vegetation has on wind flow). Gridded winds more accurately
model the effects of complex terrain (e.g., funneling through narrow canyons) during directional wind events.
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5.3.3 Relative Wildfire Hazard
A citywide relative wildfire hazard assessment was conducted in FlamMap that integrates the flame length
(representing fire intensity) and burn probability outputs discussed above. Determining wildfire hazard involves
combining two important measures—burn probability and flame length—into a single geographic information system
wildfire hazard output layer. The relative wildfire hazard modeling analysis generates five relative hazard classes
based on the intersection between burn probability and flame length as presented in Exhibit 13.
Exhibit 13. Relative Wildfire Hazard Classification Matrix
5.4 Wildfire Progression Modeling
Wildfire progression modeling was conducted to evaluate potential wildfire spread toward the Plan Area under
severe Santa Ana wind conditions, representing a high-fire-spread scenario in the region. This assessment utilized
the Minimum Travel Time (MTT) tool embedded within FlamMap.
The MTT tool is a two-dimensional fire growth model that calculates wildfire spread based on modeled fire spread
rates from an ignition source. These spread rates are used to identify minimum travel paths between cells in the
landscape, producing output data that represent the estimated number of minutes required for a wildfire to reach
a given location. As a static representation of fire behavior, MTT modeling assumes constant wind and weather
conditions over the simulation period and does not account for fire suppression, changes in weather, or urban fuels.
Results represent potential fire progression and are intended to indicate relative wildfire exposure and pathways
toward the Plan Area, rather than predict an actual wildfire event.
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The assessment applied the weather and fuel moisture values provided in Table 9, reflecting 97th percentile Santa
Ana wind conditions. Six ignition locations east of the Plan Area—comprising four continuous ignition lines and two
ignition points—were used to evaluate potential wildfire spread from a range of ignition sources over an 8-hour
period. These locations were selected to examine possible fire spread pathways toward Carlsbad, not to imply
ignition probability.
The ignition locations include:
▪ Ignition line along the eastern edge of Lake Calavera Preserve within Carlsbad
▪ Ignition line along the northern and eastern edge of Buena Vista Park just east of Carlsbad
▪ Ignition point along the western edge of Business Park Drive just east of Carlsbad
▪ Ignition point near West San Marcos Drive and Acacia Drive just east of Carlsbad
▪ Ignition line traversing Double Peak Regional Park approximately 1.25 miles east of Carlsbad
▪ Ignition line along Hidden Canyon Road approximately 0.75 miles east of Carlsbad
Results of the wildfire progression modeling, including maps depicting estimated wildfire spread and arrival times,
are provided in Section 6.3.
5.5 Wildfire Mitigation Priority Assessment
The recent expansion of the VHFHSZ and anticipated changes to the City’s Fire Suppression Zone have substantially
increased the number of parcels and land area subject to wildfire risk mitigation requirements. As a result, the
geographic extent requiring defensible space inspections, vegetation management, and other wildfire risk reduction
activities has grown considerably. Given this expanded area and the limited resources available for wildfire
prevention and enforcement activities, it is important for the City to strategically prioritize areas where mitigation
efforts will provide the greatest reduction in wildfire risk.
The results of the wildfire hazard assessment were used to develop a citywide prioritization map (Figure 9) intended
to guide defensible space inspection efforts and broader wildfire risk mitigation activities. This assessment also
helps communicate the relative variation in wildfire risk across Carlsbad, improving community awareness and
supporting more strategic allocation of fire prevention resources.
While wildfire hazard describes the likelihood and potential intensity of wildfire based on fuels, topography, and
weather conditions, wildfire risk considers how that hazard intersects with human development and other values
at risk. To evaluate the range of wildfire risk across Carlsbad, areas of development—defined as locations where
structures are present—were first identified and mapped.
Development areas were delineated using a combination of existing spatial datasets and manual review to ensure
that all structures within Carlsbad were captured. Microsoft building footprint data were first clipped to the city
boundary to provide a baseline representation of the built environment. Because this dataset does not include
structures constructed after its publication, additional buildings were manually digitized using recent aerial imagery
to capture areas of recent development. All building footprints were then buffered by 50 feet and aggregated to
create a contiguous development layer representing the spatial extent of developed areas throughout Carlsbad.
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Wildfire risk within these development areas was evaluated by assessing each area’s exposure to modeled wildfire
hazard and to large, wind-driven wildfire events. Wildfire hazard incorporates both wildfire likelihood (burn
probability) and potential fire intensity (flame length) (see Figure 6). To quantify local hazard exposure, wildfire
hazard values within a 1,000-foot radius of each pixel were summarized to represent the surrounding wildfire
environment and potential threat to nearby structures. The resulting hazard exposure values were then classified
into five relative classes using natural statistical breaks.
In addition to general wildfire hazard exposure, development areas were also evaluated for their proximity to
modeled large, Santa Ana wind-driven wildfire events (see Figure 7). Areas located closer to the perimeter of these
modeled fires were assigned higher exposure scores, reflecting the increased likelihood of fire spread into nearby
developed areas under extreme wind conditions. Exposure values were classified into five relative classes, ranging
from low exposure to very high exposure, with structures located directly adjacent to the modeled fire perimeter
receiving the highest scores and those further away assigned progressively lower values.
Exhibit 14. Relative Wildfire Hazard Classification Matrix
The resulting Wildfire Mitigation Prioritization layer was classified into five relative priority categories to illustrate
the spatial variation in wildfire risk and mitigation needs across Carlsbad. These classes represent a gradient from
lower-priority areas, where wildfire exposure and potential impacts are comparatively limited, to higher-priority areas
where conditions suggest greater potential for wildfire to threaten structures and other values at risk. This
classification framework provides a practical tool for guiding defensible space inspection programs, vegetation
management efforts, and other wildfire risk reduction initiatives by helping the City focus resources where they are
likely to achieve the greatest benefit. The results of this prioritization analysis are described in further detail in
Section 6.4.
5.6 Critical Facilities Wildfire Exposure Assessment
To supplement the field assessments conducted for critical facilities, a wildfire exposure analysis was performed to
quantify the relative wildfire threat facing each facility. This analysis builds upon the results of the wildfire hazard
assessment, using modeled wildfire likelihood and intensity as the basis for evaluating the potential exposure of
key infrastructure to wildfire.
Wildfire Risk Mitigation
Prioritization
Santa Ana
Wildfire Exposure
Relative Wildfire
Hazard
Flame Length
Burn Probability
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For each facility, a 1,500-foot buffer was generated to capture the area within which wildfire activity could directly
or indirectly affect the site. This distance was selected to account not only for direct exposure from advancing
flames, but also for indirect exposure from ember transport, which can ignite receptive fuels and structures well
ahead of the primary fire front. Within each buffer area, wildfire hazard values were summarized to characterize
the surrounding fire environment and the potential threat posed by nearby vegetation and terrain conditions.
The resulting exposure values were then classified into five relative categories using natural statistical breaks,
allowing facilities to be ranked according to their relative level of wildfire exposure. These categories include Very
Low, Low, Moderate, High, and Very High exposure. This classification provides a consistent and data-driven method
for comparing wildfire risk across facilities and helps identify locations where additional mitigation measures,
defensible space improvements, or operational planning may be warranted. The results of this assessment are
presented in Section 6.5.
5.7 Evacuation Routes and Traffic Calming Devices
Dudek conducted a simple evaluation of mapped evacuation routes in Carlsbad, as defined in the City’s General
Plan Safety Element. The focus of this assessment was to evaluate the presence of traffic calming devices and
research their effect on evacuation. Our research was focused on identifying possible alternative approaches
that could be employed that do not impact evacuation. No traffic or evacuation modeling was conducted as part
of this evaluation.
5.8 Tree Hazard Assessment
Dudek arborists conduct a hazard and risk field assessment of all trees around critical City managed infrastructure
and highly valued resources (e.g., schools and housing for persons with access and functional needs) as well as
the eucalyptus woodland area in Hosp Grove (Hosp Grove Assessment Completed February 9th, 2026). During the
assessment, Dudek’s arborists evaluated the surrounding environment and assessed each tree within 75 feet of
infrastructure. The assessment included the following:
▪ Tree Health and Structure Evaluations: Crowns, trunks, and scaffold branches were inspected for structural
soundness and health condition. Visible root collars were inspected for observable cavities and signs of decay.
▪ Site Condition Evaluations: Landscape characteristics including understory and ladder fuel conditions, tree
species, and proximity of trees to infrastructure were documented if observed.
5.8.1 Hazardous Tree Conditions
Hazardous conditions arise from a combination of volatile compounds, accumulation of dead or fine fuels, dense
canopy or understory structure, and ember generation potential. These traits significantly influence flame spread,
crown fire behavior, and structural ignition exposure. These hazards are more present in close proximity to critical
infrastructure especially in WUI areas. Trees that may contribute to increased wildfire hazards are referred to as
hazard trees in this memorandum. Trees in poor to critical health or structure; dead trees; species of concern within
75 feet of critical infrastructure; and areas with species of concern or individual hazard trees further than 75 feet
of critical infrastructure were identified as hazard trees during the field assessment.
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Several commonly occurring ornamental and naturalized species—including eucalyptus, cypress, palms, pines, and
junipers—exhibit structural and chemical characteristics that significantly increase the likelihood of ignition, flame
spread, and ember production. The following summarizes the fire hazard traits of each species group based on
current scientific and agency-based literature.
Eucalyptus
Eucalyptus species are widely recognized as high-hazard vegetation in fire-prone landscapes due to their high
volatile oil content, which makes leaves, bark, and wood highly combustible. These aromatic oils can vaporize under
heat and contribute to intense ignition and flame propagation, sometimes resulting in explosive flareups. The species
also sheds large quantities of dry bark and dead leaf litter, which accumulate at the base of trees and act as receptive
fine fuels. This shedding bark can ignite easily and carry embers significant distances, increasing spotting potential
ahead of the main fire front. In addition, eucalyptus exhibits fire-adapted regeneration traits including heat-induced
seed release and post-fire sprouting, which allows dense stands to form following fire events. These dense, uniform
stands can contribute to heavy fuel loads and elevated crown fire potential when not regularly managed.
Cypress
Several cypress communities form dense thickets with abundant dead wood, increasing both vertical and horizontal
fuel continuity. Such conditions can support high-intensity fire behavior, including crown fire. Research on postfire
population dynamics also indicates that some cypress species accumulate substantial canopy seed banks that can
ignite or contribute to fuel loading during short-interval fire cycles. These characteristics make unmanaged cypress
stands vulnerable to extreme fire behavior.
Palms
Palm species, particularly fan palm and date palm species, present significant fire hazards due to retention of dead
fronds, which form persistent “skirts” along the trunk. These skirts act as vertical ladder fuels, allowing flames to
rapidly climb into the upper canopy. The fibrous frond material readily ignites and burns intensely, often producing
large quantities of burning embers and even entire flaming fronds that can be lofted long distances in wind-driven
fire conditions. This ember production is well documented during Southern California wildfire events and increases
exposure risk for adjacent structures. While palm trunks may resist ignition when moist, the presence of dry,
unmaintained frond material substantially increases ignition probability and flame spread.
Pines
Pine species contain high levels of resin, which include volatile hydrocarbons that ignite readily and burn intensely.
This resin content enhances the combustibility of needles, bark, and sap, making pines highly receptive to both surface
and crown fire ignition. Accumulations of dry needles and lower dead branches contribute to substantial fine and
ladder fuels capable of transmitting fire into the crown. Dense stands with continuous needle litter can promote rapid
flame spread and high heat release. During combustion, pine wood and needles release large amounts of volatile
gases, generating strong flame fronts and increasing the potential for ember generation and long-range spotting.
These characteristics significantly elevate wildfire risk in unmanaged or densely stocked pine areas.
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Junipers
Juniper species are considered among the least fire-resistant shrubs and trees used in landscaping. Their foliage
and wood contain high concentrations of volatile oils and resins, which ignite rapidly and burn at high intensity.
Junipers also accumulate dense interior debris, including dead leaves and trapped litter, creating highly ignitable
fuel beds. Once ignited, junipers produce large flames and abundant embers, contributing to spot fires and rapid
fire spread. Due to their ignition susceptibility and tendency to form continuous masses when planted in groups,
junipers pose elevated risks near structures, particularly within the defensible-space zones of buildings.
5.8.2 Evaluation Methods
The field assessment was a 180° visual inspection that evaluated the tree’s crown, trunk, and trunk flare; visible
aboveground roots; and site conditions. The assessment involves inspection of the tree’s crown, branches, trunk,
and root collar for the presence of defects, such as dieback, broken or hanging branches, fungal fruiting bodies and
decay, dead branches and fronds, root lifting, and cavities. Tree attribute data, collected simultaneously with
feature positions, was linked to tree location information and stored in an internet database that is serviced by a
secure global network of servers. Evaluated trees were not physically tagged. Tree attributes including species,
common name, structural integrity, health, trunk diameter, observed defects and notes, and prioritized
management recommendations were collected for each evaluated tree. Health and structure were graded as good,
fair, poor, very poor, critical and dead. A good health or structure rating represents no apparent problems, and a
dead rating represents a dying or dead tree.
Trunk diameters were measured using a diameter tape, which provides adjusted diameter measurements when
the tape is wrapped around an object’s circumference. Diameter measurements were collected using protocols
provided by the Council of Tree and Landscape Appraisers in the Guide for Plant Appraisal (CTLA 2000). The trunk
diameter measurement of each tree was taken at 4.5 feet above the ground along the trunk axis, with common
exceptions. For example, in cases in which a trunk was on a slope, the 4.5-foot aboveground distance was
approximated as the average of the shortest and longest sides of the trunk (i.e., the uphill side and downhill side
of a trunk, respectively), and the measurement was made at this point. Composite trunk diameters for multiple-
stem trees were calculated according to International Society of Arboriculture (ISA) standards. According to these
standards, the sum of all stem diameters was calculated to ascertain composite trunk diameter values for
multiple-stem trees.
Site conditions such as general maintenance practices, site cleanliness, vegetation density, location and height,
irrigation, and infrastructure location were evaluated. Sites were prioritized by accessibility. CFD staff provided
access to City fire houses, water towers, and wastewater facilities previously identified as critical infrastructure by
City staff. Based on direction from CFD, Dudek’s arborists inventoried all trees that were within 75 feet of all
accessible critical infrastructure. Individual hazard trees or areas with multiple hazard trees that were further than
75 feet from critical infrastructure were inventoried if observed.
Individual hazard trees were inventoried throughout the 257 acres of Hosp Grove. Other highly valued resources
such as schools and housing for persons with access and functional needs were inspected from the adjacent street
in a vehicle or on foot. Dudek arborists collected representative photographs of all sites during site evaluations
which were provided to city staff.
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In addition to the results provided in Section 6.7, Dudek will also provide CFD with a georeferenced shapefile
identifying all tree survey locations and their management priority.
Survey Limitations
No root crown excavations or investigations, internal probing, or aerial canopy inspections were performed during
the inventory. Therefore, the presence or absence of internal decay or other hidden or inaccessible inferiorities in
individual trees could not be confirmed. Level 2 Basic Tree Risk Assessments and Level 3 Advanced Assessments
were not conducted as part of the field assessment. Individual tree assessments or comprehensive evaluations
were not possible at schools or housing facilities because the Dudek arborists had not been provided with sufficient
access to these facilities to evaluate individual trees within 75 feet of the structures.
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6 Wildfire Hazard and Risk
Assessment Results
6.1 Field Assessment Results
It was observed in the field assessment that the City’s development pattern places many neighborhoods along
broad ridgelines adjacent to steep canyons and protected open space, creating extensive WUI edge conditions. The
City’s Growth Management Program requires 15% of developable land in certain Local Facilities Management
Zones to be set aside for open space concurrent with development increases overall WUI exposure, while fuel
management limitations in preserves constrain vegetation treatment options. Additionally, many residential,
commercial, and critical facilities lack adequate defensible space due to preserve management guidelines and the
absence of annual maintenance and enforcement. As a result, many residential developments and several critical
facilities, such as the Police/Fire Public Safety Complex, lack adequate separation from steep, chaparral-covered
slopes within the state recommended 100-foot defensible space zone.
The site visit found that most modern developments and critical infrastructure in Carlsbad are built to fire-resistant
standards and appear highly ember resistant. However, the older portions of Carlsbad, such as the areas within
and adjacent to Carlsbad Village, contain many structures that are highly vulnerable to ember and fire exposure.
Rancho Carlsbad mobile home park, for example, lies in relative proximity to wildland vegetation, leaving it
susceptible to embers and wildfire despite generally adequate defensible space, highlighting the need for ongoing
vegetation maintenance in this area. Open space areas within Carlsbad are dominated by coastal sage scrub and
chaparral, with oak woodland and riparian corridors occurring in localized areas, and relatively limited annual grass
coverage compared to other Southern California regions. Non-native eucalyptus groves are present, most notably
at Hosp Grove Park, where current vegetation management appears effective in minimizing surface fuel
accumulation and wildfire hazard.
Over the course of several days, Dudek staff visited 55 critical facilities. At each facility, risk factors such as
structural condition and defensible space were recorded. Facilities assessed as having good defensible space
demonstrated sufficient vegetation management, while those with poor defensible space exhibited hazardous
vegetation conditions in proximity to structures.
Each facility was then classified into the following four categories.
▪ Appears Ember Resistant, Good Defensible Space
▪ Appears Ember Resistant, Poor Defensible Space
▪ Ember Vulnerable, Good Defensible Space
▪ Ember Vulnerable, Needs Defensible Space
6.2 Wildfire Hazard Modeling Results
Results of the wildfire hazard assessment are provided in Figures (6-8) and display outputs for flame length, relative
wildfire hazard, and fire progression.
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6.2.1 Flame Length
As illustrated in Figure 6 (Flame Length), modeled flame lengths are projected to exceed 11 feet across much of
the vegetated portions of the Plan Area under severe wildfire conditions. The highest flame lengths are generally
associated with areas dominated by dense shrub fuels, particularly chaparral and coastal sage scrub, where high
fuel loads and continuous vegetation can support intense fire behavior. Elevated flame lengths are also observed
in locations where fire behavior modeling indicates the potential for crown fire, allowing flames to move through
the upper canopy of shrubs or trees and significantly increase overall fire intensity.
Topographic conditions further influence these patterns of fire behavior. Flame lengths tend to increase along
ridgelines and in areas where slopes are aligned with prevailing wind directions. Under these conditions, wind
speeds can accelerate as they move over ridges and through drainages, while upslope fire spread can preheat and
dry fuels ahead of the fire front. The combination of wind alignment and slope can substantially increase rates of
spread and flame length, resulting in more intense and difficult-to-control fire behavior in these locations.
In many areas throughout the Plan Area, residential development occurs in close proximity to locations where
modeled flame lengths exceed 15 feet, often without sufficient separation or buffering between structures and
adjacent wildland vegetation. These conditions are most observed where neighborhoods border open space areas
designated within the City’s HMP, where natural vegetation is preserved and fuel modification is limited or absent.
In these areas, the close interface between high-intensity wildland fuels and residential structures can increase
structure exposure during a wildfire event, particularly under wind-driven conditions. These findings highlight the
importance of strategic vegetation management, defensible space implementation, and appropriately designed
fuel modification zones along the wildland–urban interface to reduce wildfire impacts to nearby communities.
6.2.2 Burn Probability
Burn probability is influenced in part by the potential size and continuity of wildfire spread across the landscape. As
a result, areas with higher burn probability in Carlsbad typically correspond to locations where fire modeling
indicates that larger wildfires are more likely to occur and spread across extensive, continuous areas of vegetation,
such as large open space preserves or undeveloped wildland areas. These larger, contiguous fuel beds allow fires
to spread more freely and sustain longer runs, increasing the likelihood that a given location will burn during
simulated fire events.
In contrast, smaller and more fragmented open space areas generally exhibit lower modeled burn probabilities
because fire spread is more likely to be interrupted by development, roads, or other fuel breaks that limit fire
growth and reduce the size of potential wildfire events. However, where open space areas remain connected
through continuous habitat corridors or vegetated linkages, these corridors can facilitate the continued spread
of wildfire across the landscape. Such connectivity allows fires to move between otherwise separated fuel beds,
effectively increasing the size of potential fire runs and resulting in higher burn probabilities along these
connected open space networks.
6.2.3 Relative Wildfire Hazard
As described in Section 5.3, the relative wildfire hazard assessment integrates fire behavior modeling outputs for
flame length and burn probability to evaluate where areas of both high wildfire intensity and higher likelihood of
burning occur across Carlsbad. This approach provides a more comprehensive understanding of wildfire hazards
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than either metric alone, as it captures both the potential intensity of fire behavior and the likelihood that a given
area will experience wildfire. It is important to note that this analysis represents a relative assessment of wildfire
hazard, meaning the results are scaled based on the range of modeled conditions observed across Carlsbad’s open
space areas rather than representing an absolute measure of wildfire risk. As such, the hazard classes are intended
to identify areas that are comparatively more or less hazardous within the context of Carlsbad’s landscape and fuel
conditions (See Figure 7).
These locally derived hazard maps differ from the statewide hazard classifications produced by CAL FIRE’s Fire
Hazard Severity Zone (FHSZ) maps, which are developed using standardized modeling approaches and datasets
applied consistently across the entire state. While statewide maps provide an important regulatory and planning
framework, their coarse resolution and uniform methodology applied statewide may not fully capture localized
conditions such as site-specific vegetation patterns, fine-scale topography, fuel continuity, and locally dominant
wind patterns.
Relative wildfire hazard was categorized into five classes ranging from 1 to 5. Areas classified as Class 1 represent
locations with comparatively lower modeled hazard, generally associated with lower burn probability, lower
predicted flame lengths, or both. At the opposite end of the scale, Class 5 represents areas with the highest relative
hazard, where the modeling indicates a combination of elevated burn probability and the potential for more intense
fire behavior, including longer flame lengths. Intermediate classes (2–4) represent progressively increasing levels
of relative hazard between these two extremes. Mapping these relative hazard classes allows for a spatial
understanding of how wildfire hazard varies across Carlsbad’s open space areas and provides a useful framework
for prioritizing vegetation management, fuel treatments, and other wildfire mitigation strategies in locations where
wildfire intensity and likelihood intersect.
A graphical depiction of relative wildfire hazard across Carlsbad is provided in Figure 7. Because hazard rankings
are strongly influenced by wildfire likelihood, larger and more continuous open space areas often exhibit higher
relative hazard scores. These landscapes typically contain more continuous vegetation fuels and are more likely to
experience fire spread over time compared to smaller or more fragmented open space areas. Where these larger
open spaces also contain higher-hazard vegetation types such as dense chaparral or coastal scrub capable of
supporting intense fire behavior, the resulting hazard classifications tend to be higher. The distribution of relative
wildfire hazard classifications across the city are provided below in Table 10.
Table 10. Relative Wildfire Hazard Classifications within the City’s Open Spaces
Relative Wildfire Hazard Class Acres Percentage of Total
1 293 4%
2 759 11%
3 1,550 23%
4 2,780 41%
5 1,405 21%
Many of the areas identified as having the highest relative wildfire hazard are located within Carlsbad’s eastern
region. In this portion of Carlsbad, open space areas are generally larger, more continuous, and more directly
connected to surrounding wildland landscapes outside the city boundary. This connectivity increases the likelihood
that wildfire originating in adjacent regional wildlands may spread into the City’s open space system. The potential
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for fire spread into these areas is particularly elevated during offshore wind events, when strong easterly winds can
drive wildfire rapidly westward from adjacent open space areas beyond the city boundary.
Additional areas of elevated hazard are distributed throughout Carlsbad, often occurring immediately adjacent to
developed neighborhoods. In these locations, continuous vegetated fuels extend close to structures and
infrastructure, creating conditions where intense wildfire behavior may occur near the WUI. As a result, these areas
represent locations where wildfire hazard and potential exposure to development intersect. Identifying these spatial
patterns of relative hazard provides an important foundation for prioritizing vegetation management, and other
mitigation strategies intended to reduce wildfire intensity and limit the potential for fire spread into developed
portions of Carlsbad.
6.3 Wildfire Progression Modeling
Results of the fire progression modeling are provided in Figure 8. Under peak Santa Ana wind conditions, wildfire is
modeled to advance rapidly westward as strong, dry easterly winds align with the region’s topography. In particular,
several east–west oriented drainages provide efficient pathways for fire spread, allowing fire to move quickly through
vegetated corridors and into developed areas. When drainages align with the wind direction, fire behavior intensifies
as wind speeds are accelerated. This alignment can substantially increase the rate of spread and produce longer
flame lengths, enabling fire to rapidly traverse the landscape and overcome natural or constructed barriers.
The modeling also indicates that in several locations wildfire may spread from the wildland edge into the core of
Carlsbad through interconnected open spaces. These areas can function as continuous fuel pathways that allow
fire to travel further into the urban environment, particularly when embers generated under strong wind conditions
ignite spot fires ahead of the main fire front. As a result, wildfire exposure is not limited solely to structures
immediately adjacent to the wildland interface but may extend further into the community where these connected
open space networks exist.
Given that the majority of structure losses from wildfire in California, and particularly within San Diego County, have
historically occurred during large fires caused by extreme wind events, communities located adjacent to these
modeled fire progression pathways face an elevated risk of structure loss. Under Santa Ana conditions, high wind
speeds can transport embers over long distances, ignite receptive fuels within neighborhoods, and rapidly
overwhelm suppression efforts. Consequently, neighborhoods situated near the identified fire perimeters,
especially those bordering drainages or large connected open space areas, should be considered priority areas for
mitigation measures such as enhanced defensible space, structural hardening, and strategic vegetation
management in open space areas to reduce community wildfire risk.
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6.4 Wildfire Mitigation Priority Assessment Results
The Wildfire Mitigation Prioritization layer was classified into five relative priority categories to illustrate the spatial
distribution of priority mitigation needs across Carlsbad. The categories represent a gradient from lower-priority
areas, where wildfire exposure and potential impacts are relatively limited, to higher-priority areas where conditions
indicate a greater potential for wildfire to threaten structures and other values at risk. This classification identifies
locations where mitigation needs are greatest and provides a basis for directing defensible space inspections,
vegetation management activities, and other wildfire risk reduction efforts toward areas where they are likely to
yield the greatest benefit. Table 11 below provides the number of structures within each priority level.
Table 11. Relative Wildfire Hazard Classifications within the Plan Area’s Open Space
Wildfire Mitigation Priority Classification Number of Structures
5 627
4 4,045
3 7,437
2 2,168
1 21,276
As shown in Figure 9, the highest-priority (Class 5) areas are predominantly located along the eastern edges of
Carlsbad’s developed areas, where residential and other structures are immediately adjacent to extensive open
space or natural vegetation. In many of these locations, defensible space is insufficient to mitigate the fire behavior
anticipated based on the modeled scenarios, increasing the vulnerability of structures to wildfire exposure. These
eastern edges are particularly susceptible to direct impacts from large, wind-driven wildfires approaching from the
east, where topography and prevailing winds can accelerate fire spread and intensity.
In addition to the eastern perimeter, high-priority (Class 4) areas are also distributed throughout Carlsbad’s interior,
particularly where dense, high-hazard vegetation occurs close to structures. These interior clusters often represent
pockets of elevated risk where local fuel conditions such as chaparral, mixed shrubs, or heavily vegetated riparian
corridors can facilitate rapid fire spread and threaten the built environments. Collectively, this assessment
highlights and prioritizes high-risk zones as key targets for focused wildfire mitigation, including priority defensible
space improvements, increased levels of vegetation management, and other risk reduction measures such as
targeted community outreach and education. Specific project areas will be determined through the CWPP process.
While not a comprehensive list, examples of high priority areas are provided below.
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Exhibit 15. Example high priority areas throughout Carlsbad.
High Priority Area Surrounding Box Canyon High Priority Area Near Twain Avenue
High Priority Area Near the City Police and Fire HQ High Priority Area near Rancho Carillo
High Priority Area near La Golondrina Street
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6.5 Critical Facilities Wildfire Exposure
Assessment Results
Similar to the relative wildfire hazard assessment described above, the results of this analysis are relative in nature
and are intended to represent the range of modeled exposure conditions observed across Carlsbad. The analysis
evaluates the potential for wildfire to affect critical facilities based on surrounding wildfire behavior and likelihood
metrics, allowing facilities to be compared to one another in terms of their relative level of exposure.
For the purposes of this assessment, facilities were categorized into five exposure classes, ranging from Very Low
to Very High. These classes reflect increasing levels of potential wildfire exposure based on the modeled conditions
surrounding each facility. Facilities assigned to higher exposure classes are generally located in closer proximity to
areas with elevated burn probability, more intense modeled fire behavior, or landscape features that may facilitate
wildfire spread.
The distribution of facilities within each exposure class is summarized in Table 12. This classification framework
helps identify facilities that may warrant additional consideration for wildfire preparedness, defensible space
enhancements, or other mitigation measures to reduce potential wildfire impacts. As provided below, 40% of the
assessed critical facilities are classified as having a high or very high exposure to wildfire.
Table 12. Critical Facilities Wildfire Exposure
Wildfire Exposure Class Number of Facilities Percentage of Total
Very Low 12 22%
Low 10 18%
Moderate 11 20%
High 11 20%
Very High 11 20%
Total: 55
Facilities classified as having Moderate, High, or Very High wildfire exposure were further evaluated alongside
findings from the field assessments to identify locations that may warrant priority mitigation measures. Comparing
the modeled exposure results with on-the-ground observations allowed for a more refined understanding of site-
specific vulnerabilities, including defensible space and structure condition.
6.6 Evacuation Routes and Traffic Calming Devices
The City’s General Plan Safety Element (City of Carlsbad 2024) identifies a system of evacuation routes that remain
generally unobstructed by physical hazards and are intended to function effectively during emergencies. These
routes form the backbone of community evacuation planning and hazard response operations. While these
corridors do not typically face chronic congestion or structural impediments, their performance during emergencies
can be constrained by limited roadway capacity, particularly along two-lane facilities such as Las Flores Drive,
Levante Street, and Jefferson Street, and at key chokepoints such as major arterial intersections, at grade rail
crossings, and freeway interchanges.
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In addition to geometric and capacity constraints, the placement of traffic calming devices along evacuation or
emergency response routes can introduce additional delays. Traffic calming features, such as speed humps, chicanes,
curb extensions, raised crosswalks, and pedestrian refuge islands, serve an important role in reducing vehicle speeds
and enhancing safety for road users. However, research has shown that these same features can slow emergency
responders and reduce evacuation throughput. For example, empirical studies demonstrate that each vertical traffic
calming device can introduce 1.4 to 4.3 seconds of delay for ambulances depending on traffic conditions and vehicle
type (Garcia et al. 2013). Federal guidance similarly notes that traffic calming measures may impede the movement
of fire and EMS vehicles, emphasizing the need to coordinate with emergency services during project planning and
implementation (FHA n.d.). These federal considerations are consistent with the California Fire Code, which restricts
traffic calming on fire access roads without explicit approval from the Fire Code Official.
The City’s own operational experience reflects these concerns. During the development of traffic calming
improvements in the Barrio Neighborhood, CFD noted that vertical devices such as raised speed tables can slow
response times and therefore must be monitored within a defined radius of fire response facilities to limit
operational impacts. This local observation aligns with broader research on the sensitivity of emergency response
times to vertical roadway features and reinforces the Public Safety Element’s stated priority of maintaining
unobstructed and functional emergency access routes during hazard events (City of Carlsbad 2024).
These operational constraints take on heightened importance during large-scale emergencies, particularly wildfires
or coastal hazard events that may require rapid, high-volume evacuation. Studies analyzing wildfire evacuations
using connected vehicle datasets show that roadway bottlenecks, speed reducing features, and other impediments
to flow can significantly worsen congestion during short notice evacuations by reducing throughput at critical points
and creating cascading delays throughout the network (Garcia et al. 2013, Rohaert et al. 2023). Additional research
from the 2020 Glass Fire evacuation demonstrates that roadway design, background traffic volume, and traffic
control features directly influence evacuation performance, underscoring the importance of minimizing speed
reducing devices on critical evacuation corridors in WUI communities (Rohaert et al. 2023). These findings support
the City’s General Plan directive to sustain safe, efficient evacuation pathways and to reduce barriers to emergency
mobility in areas exposed to wildfire.
6.7 Tree Hazard Assessment Results
In total, 1,984 individual trees were evaluated and mapped during the inventory. Dudek arborists were granted
access to 42 critical facilities to inventory trees within 75 feet of the critical infrastructure. The surveyed trees are
both naturally occurring and planted ornamentals. Table 13. Total Surveyed details the 73 different genera and
122 species documented during the inventory. Table 14. Species of Concern details the 36 tree species considered
to be a wildfire concern.
Table 13. Total Surveyed Trees
Tree Species Common Name Number of Trees
Cupaniopsis anacardioides Carrotwood 118
Juniperus chinensis Chinese Juniper 91
Pinus eldarica Mondell Pine 80
Syagrus romanzoffianum Queen Palm 77
Olea europaea Olive 72
Eucalyptus sideroxylon Red Ironbark 68
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Table 13. Total Surveyed Trees
Tree Species Common Name Number of Trees
Eucalyptus citriodora Lemon Gum 67
Quercus agrifolia Coast Live Oak 65
Washingtonia robusta Mexican Fan Palm 63
Lophostemon confertus Brisbane Box 61
Phoenix dactylifera Date Palm 60
Pinus halepensis Aleppo Pine 46
Eucalyptus cladocalyx Sugar Gum 46
Cassia leptophylla Gold Medallion Tree 45
Eucalyptus polyanthemos Silver Dollar Gum 40
Melaleuca quinquenervia Paperbark 40
Afrocarpus falcatus African Fern Pine 37
Eucalyptus (spp.) Eucalyptus 36
Jacaranda mimosifolia Jacaranda 35
Pittosporum tobira Mock Orange 35
Platanus x hispanica London Plane 34
Schinus molle Peruvian Pepper 32
Chamaecyparis lawsoniana Port Orford Cedar 31
Schinus terebinthifolius Brazilian Pepper 31
Heteromeles arbutifolia Toyon 30
Phoenix roebelenii Pygmy Date Palm 25
Cercis canadensis Eastern Redbud 23
Ulmus parvifolia Chinese Elm 22
Yucca gloriosa Spanish Dagger 21
Magnolia grandiflora Southern Magnolia 21
Pinus canariensis Canary Island Pine 20
Other NA 512
Total 1,984
Table 14. Surveyed Species of Concern
Tree Species Common Name Number of Trees
Juniperus chinensis Chinese Juniper 91
Pinus eldarica Mondell Pine 80
Syagrus romanzoffianum Queen Palm 77
Eucalyptus sideroxylon Red Ironbark 68
Eucalyptus citriodora Lemon Gum 67
Washingtonia robusta Mexican Fan Palm 63
Phoenix dactylifera Date Palm 60
Pinus halepensis Aleppo Pine 46
Eucalyptus cladocalyx Sugar Gum 46
Eucalyptus polyanthemos Silver Dollar Gum 40
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Table 14. Surveyed Species of Concern
Tree Species Common Name Number of Trees
Eucalyptus (spp.) Eucalyptus 36
Chamaecyparis lawsoniana Port Orford Cedar 31
Phoenix roebelenii Pygmy Date Palm 25
Pinus canariensis Canary Island Pine 20
Unknown Dead Tree Unknown Dead Tree 18
Pinus (spp.) Pine 12
Phoenix reclinata Senegal Date Palm 11
Eucalyptus camaldulensis River Red Gum 10
Eucalyptus maculata Spotted Gum 8
Eucalyptus conferruminata Spider Gum 7
Phoenix canariensis Canary Island Date Palm 6
Cupressus sempervirens Italian Cypress 6
Pinus pinea Stone Pine 5
Archontophoenix cunninghamiana King Palm 5
Juniperus (spp.) Juniper 3
Beaucarnea recurvata Ponytail Palm 3
Butia odorata Pindo Palm 3
Pinus torreyana Torrey Pine 2
Dypsis (spp.) Dypsis Palm 2
Cordyline australis Cabbage Palm 2
Washingtonia filifera California Fan Palm 1
Unknown Palm Unknown Palm 1
Eucalyptus leucoxylon White Ironbark 1
Pinus radiata Monterey Pine 1
Cupressus spp. Cypress 1
Chamaerops humilis Mediterranean Fan Palm 1
Total 859
Of the 1,984 inventoried trees, 370 (18.6%) trees are in good health, 1,333 (67.2%) trees are in fair health, 127
(6.4%) trees are in poor health, 50 (2.5%) trees are in critical health, and 104 (5.2%) trees are dead. Of the 1,984
inventoried trees, 60 trees (3.02%) have good structure, 1,654 (83.3%) trees have fair structure, 124 (6.25%) trees
have poor structure, 35 (1.7%) trees have very poor structure, 7 (.35%) trees have critical structure, and 104 (5.2%)
trees are dead.
In total, 814 inventoried trees were identified with short-term management needs. Table 15 details the priority level
each recommended management action is assigned. Priority 1 indicates the highest priority while priority 4
indicates a lesser priority. Trees that were dead, or in very poor or critical health and structure were recommended
for a priority one removal. These trees have varying levels of major structural defects that include split or fallen
trunks, severe lean, trunk decay, or severe pest or disease. Trees with moderate structural concerns, early signs of
decay, or volunteers were recommended for priority 2 removal. Trees that were growing in dense understory or fuel
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ladder conditions were recommended for priority 2 pruning. 124 trees were identified for selective crown raising so
that fuel ladder conditions are minimized.
Table 15. Tree Management Priorities
Priority Level Recommended Action Number of Trees
Priority 1 Removal 198
Priority 2 Crown Raise or Removal 142
Priority 3 Crown Clean 372
Priority 4 Annual Inspection 102
Total 814
372 trees were in fair to poor overall condition, exhibiting minor to moderate dieback with some deadwood in the
canopy. These trees are likely to require regular maintenance such as crown cleaning to remove the dead material
in the crown. Trees recommended for crown cleaning are considered less of a wildfire risk due to their condition
and as such are categorized as a priority 3 management need. Trees recommended for annual inspection (Priority
4) exhibited fair to good health with minor issues including lean or small wounds that require monitoring.
The most observed conditions during these site evaluations were the presence of dead or dying trees, spacing
between trees or adjacent vegetation and understory.
A focused assessment was conducted for the Hosp Grove. Hosp Grove is a dense stand of mature and over-mature
eucalyptus trees with scattered areas of pines. Many areas of the grove are in need of maintenance and include
fallen trees, stumps, and dead standing trees throughout. Several hazard trees were inventoried when walking the
trails that run throughout the area. The woodland is generally in poor condition due to insufficient water availability
for the species that make up the majority of the population. Signs of invasive pests such as Eucalyptus long horned
beetle were observed which is likely contributing to the decline of the mature eucalyptus. There is low regeneration
of trees in the woodland besides the few that have been planted in recent years. Dead, dying, and dangerous trees
identified during the inventory are recommended for priority 1 removals. Fallen trees and stumps should be
removed to reduce dead material in the area. Annual inspections should occur throughout the grove to identify
trees for removal.
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7 Fire Suppression Zone Modeling
As described in Section 2.5.2, the city has extended defensible space and fuel modification requirements for
structures located within the Fire Suppression Zone. Prior to the initiation of this WHRA, the Fire Suppression Zone
encompassed roughly 9,000 acres within the city and covered 13,414 parcels.
However, due to the expanded Very High FHSZ within Carlsbad and the updated relative wildfire hazard modeling
conducted as part of this WHRA (Section 6.2.3), the City’s Fire Suppression Zone has been revised to meet state
requirements and more comprehensively address wildfire risk. These updates are designed to ensure that both
existing and future development within high-risk areas are subject to appropriate wildfire risk reduction measures,
including defensible space and structural protection standards. By aligning the Fire Suppression Zone boundaries
with current hazard data and modeling insights, the city can more effectively reduce the potential for wildfire
impacts on communities, critical infrastructure, and other values at risk.
The updated Fire Suppression Zone includes an additional 7,214 parcels and ensures that parcels located adjacent
to hazardous vegetation are now included within the zone. In contrast, the previous mapping provided limited
buffers around open space areas, leaving many developed parcels at the urban-wildland interface outside of the
Fire Suppression Zone despite their proximity to hazardous areas. By incorporating these adjacent parcels, the
updated zone more effectively captures areas where wildfire exposure is elevated, ensuring that defensible space
requirements and other risk mitigation measures apply to all properties at greatest risk. This approach strengthens
the City’s ability to reduce wildfire impacts and creates a more comprehensive and defensible framework for
protecting community assets.
7.1 Fire Suppression Zone Modeling Methods
The City’s Fire Suppression Zone was updated to include the LRA Very High FHSZ and hazard areas identified
through the relative wildfire hazard assessment. The following diagram describes the data sets that were merged
to update the Fire Suppression Zone boundary.
Updated Fire
Suppression Zone
CAL FIRE Very High Fire
Hazard Severity Zone (LRA)
Moderate-Very High Relative Wildfire Hazard Areas (buffered
by 250-feet)
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7.2 Fire Suppression Zone Modeling Results
The City’s updated Fire Suppression Zone is provided in Figure 10. Figure 11 isolates the Fire Suppression Zone to
development areas only. The majority of the recent additions to the Fire Suppression Zone result from the expanded
VHFHSZ. Unlike the 2007 statewide FHSZ mapping, the updated maps incorporate wildfire hazards in urban areas
caused by airborne embers. This refinement has substantially extended the VHFHSZ into urbanized portions of
Carlsbad, increasing the area now subject to Fire Suppression Zone standards.
Overall, the Fire Suppression Zone now covers 13,799 acres, representing approximately 6,510 acres of Carlsbad’s
development areas. The expansion adds 7,214 parcels, bringing the total number of parcels within the zone to
13,414. Roughly 12,500 structures now fall within the zone, a significant increase from the prior mapping which
included 4,631 structures.
7.3 Implications of Updated Fire Suppression Zone
The expansion of the Fire Suppression Zone has several important implications for the City’s wildfire risk management
efforts. By extending the zone to include additional development areas, particularly those newly designated within the
expanded VHFHSZ and urbanized areas at risk from airborne embers, the city’s defensible space requirements, fuel
modification standards, and other mitigation measures will apply to a substantially larger area.
With 7,214 additional parcels and an estimated 12,500 structures now included, the absence of an existing
inspection program means that establishing effective compliance oversight will require significant planning and
resources. Developing and staffing an inspection program (See Section 8) to ensure adherence to Fire Suppression
Zone standards will create substantial administrative and operational demands, necessitating prioritization
strategies and recruitment of additional personnel. While expansion of the Fire Suppression Zone and the creation
of a Defensible Space Inspection Program improves the City’s ability to proactively manage wildfire risk and protect
both public and private assets, it underscores the importance of strategic planning, resource allocation, and
program development to ensure that inspection, enforcement, and mitigation efforts are effective and sustainable
over the long term.
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8 Wildfire Risk
Reduction Recommendations
The city recognizes the potential for severe and damaging wildfires within the Plan Area. The following sections
identify potential actions and projects to minimize wildfire impacts. These potential projects and actions would
require further staff analysis, funding, completion of any necessary environmental review, and approval by the
appropriate regulatory authorities prior to implementation.
While this WHRA establishes an initial framework for wildfire risk reduction, the action plan is anticipated to be
substantially expanded and refined through the development of the CWPP. The CWPP process involves a more
comprehensive planning effort that includes collaboration with local stakeholders, land managers, resource
agencies, fire agencies, and community members to identify and prioritize wildfire mitigation strategies. Through
this process, additional input will be gathered from residents, homeowner associations, regional partners, and other
interested parties to ensure that mitigation actions reflect both local conditions and community priorities.
As part of the CWPP development process, potential vegetation management, fuel reduction, and wildfire resilience
projects will be evaluated in greater detail, resulting in more refined treatment areas, clearer implementation
strategies, and prioritized project recommendations. This effort typically includes improved mapping of candidate
treatment areas, identification of implementation partners, and evaluation of project feasibility, cost, and potential
benefits for wildfire risk reduction and ecosystem health. The CWPP process may also identify new project
opportunities and mitigation strategies not captured in the initial WHRA framework.
Ultimately, the CWPP will build upon the foundation established in this WHRA to produce a more robust, community-
informed action plan that better supports long-term wildfire preparedness, mitigation, and funding opportunities for
the City and its surrounding communities. The CWPP will be created as a living document to allow for ongoing
management, updates, and community input intended to reduce the impact of wildfires in the Plan Area.
8.1 Vegetation Management
Vegetation management is a key strategy for reducing wildfire risk within Carlsbad. Because all vegetation will burn
under the right conditions (Reinhardt et al. 2008), the objective is not to eliminate vegetation, but to moderate
potential fire behavior near communities and critical infrastructure by reducing fuel loads and adjusting the
structure, composition, and spacing (both horizontal and vertical) of retained vegetation.
The following sections provide priority recommendations related to vegetation management in the Wildland-
Urban Interface.
Different vegetation management treatments (e.g., fuel breaks, shaded fuel breaks, defensible space zones) and
techniques (e.g., grazing, manual thinning) are applied to achieve site-specific objectives, which vary based on
vegetation type, structure, condition, and regulatory limitations. Vegetation management projects identified in this
WHRA are expected to be refined during later stages of project planning throughout the implementation of the
CWPP, when detailed management prescriptions and treatment boundaries will be defined. The following sections
describe vegetation management types, recommended treatment standards, and techniques that may be used to
implement the vegetation management projects outlined in this CWPP.
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8.1.1 Wildland-Urban Interface Fuels Reduction
Priority Recommendations
The following recommendations are provided to address fuels reduction in the WUI. These recommendations are
anticipated to be refined/expanded during the CWPP process.
▪ Revise the City’s Landscape Manual Fuel Modification Zone guidelines to reflect the State Minimum
Standards for defensible space (Title 14 California Code of Regulations § 1299.03).
- Fuel Modification Zones less than 100-feet in width may be allowed when warranted based on expected
fire behavior and other factors such as firewalls and code exceeding fire hardened construction. As a
general rule, fuel modification zone widths should be roughly twice the width of the anticipated flame
length during worst case conditions.
- For example, maximum anticipated flame lengths of roughly 50 feet in high load chaparral vegetation
would require 100 feet of fuel modification to protect structures from radiant heat.
▪ Conduct and maintain vegetation management/fuel reduction around critical infrastructure and facilities,
major roadways, high-risk communities, and evacuation routes.
▪ For communities, prioritize WUI fuels reduction and defensible space inspections for communities in high
priority areas as identified in the Wildfire Mitigation Priority map (Figure 9).
▪ Encourage neighborhood-scale defensible space efforts to achieve continuous and coordinated
hazard reduction.
▪ For critical facilities, prioritize WUI fuels reduction and defensible space around facilities with high wildfire
exposure and insufficient defensible space or ignition vulnerable construction
▪ Prioritize hazard tree removal/management for high priority trees
▪ Develop a City-wide Tree Removal and Replacement Program for high hazard tree species in highest
risk communities.
▪ Update the Community Forest Management Plan to address the removal and replacement of high hazard
tree species
8.1.2 Wildland Fuels Reduction Priority Recommendations
The following recommendations are provided to address fuels reduction in the wildland vegetation and open
space areas outside of the defensible space areas. These recommendations
are anticipated to be refined/expanded during the CWPP process.
▪ Establish strategic fuel reduction zones within open-space areas adjacent to communities to reduce
wildfire spread and protect community assets. Identify treatment areas within the Fire Management Plan
as referenced in the HMP.
▪ Prioritize wildland fuels reduction in high hazard areas as identified through the Relative Wildfire Hazard
Assessment (See Figure 7).
▪ Identify specific priority vegetation management units within open-space areas during the CWPP process.
▪ Implement best management practices (BMPs) to prevent the establishment of invasive species
following fuels reduction activities.
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▪ Ensure appropriate environmental review is conducted and required regulatory approvals are
obtained prior to implementing fuels reduction projects.
▪ Develop maintenance cycles for vegetation management projects in order to achieve long-term benefits.
Where possible, utilize Cal VTP or other CEQA streamlining tools for the environmental review process
when planning and implementing vegetation management projects.
▪ Conduct public outreach and education in communities where vegetation management projects are
proposed prior to initiating work.
▪ Evaluate opportunities to develop grants, subsidies, or incentive programs to support property owners in
completing and maintaining defensible space vegetation management.
▪ Work with HOAs and communities to develop an acacia removal and replacement program
▪ Prior to the completion of the CWPP, inspect existing Fuel Modification Zones outside of HMP areas and
ensure compliance with City requirements
8.1.3 Vegetation Management within Habitat Management Plan
Areas Priority Recommendations
The following recommendations are provided to address fuels reduction specifically in the City’s lands mapped
within the HMP. These recommendations are anticipated to be refined/expanded during the CWPP process.
▪ Address and resolve the self-imposed limitations of the HMP that impede vegetation management activities
attempting to improve public safety
▪ As part of the CWPP, develop a Fire Management Plan as stated in the HMP to define and map fuel
modification zones within the HMP preserve areas that should be managed to prevent structure losses
from wildfire.
- As stated in the City’s Open Space Management Plan, fire management guidelines within the Fire
Management Plan should be consistent with current accepted fire management mandates.
▪ As part of the CWPP, identify areas where the existing 60-foot setback should be increased to prevent
structure loss from direct flame contact and radiant heat exposure.
▪ As part of the CWPP, identify landscape-level vegetation management within the HMP which if implemented
will significantly improve community safety.
▪ Ensure that vegetation management within the HMP follows applicable environmental regulations and review.
8.2 Structural Ignitability
There are two main components to reducing structural ignitability: defensible space and structural hardening.
Structures ignite via direct fire exposure (flame impingement, convection, radiation) or via ember exposure. To
reduce structural ignitability, efforts need to address direct fire and ember exposure. Addressing structural ignition
potential is an effective mitigation strategy for preventing wildfires and increasing WUI ignition resistance (Zhou
2013). Research has found that structural characteristics, especially roofing, play a significant role in reducing
structural vulnerability to fire and the likelihood of burning (Gorte and Bracmort 2012; Kolden and Henson 2019;
Manzello et al. 2011; Syphard et al. 2017; Zhou 2013). Further, reducing a structure's likelihood of ignition reduces
the risk for individual homeowners and the risk associated with fire spreading to other homes and wildland areas
(Mockrin et al. 2020).
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Reducing fire exposure is achieved via vegetation management in defensible space areas. An additional concept
increasingly emphasized in wildfire mitigation is Zone 0, often referred to as the ember-resistant zone, which
generally includes the area within the first 0 to 5 feet immediately surrounding a structure. Research conducted by
the Insurance Institute for Business & Home Safety and the National Institute of Standards and Technology has
found that conditions within this immediate area are one of the most significant indicators of whether a structure
will survive a wildfire. During wildfire events, the majority of structure ignitions occur from wind-driven embers that
accumulate in combustible materials adjacent to buildings. If combustible vegetation, mulch, wood fencing, or other
ignitable materials are present within this zone, embers can readily ignite them and allow fire to spread directly to
the structure. Maintaining Zone 0 as a noncombustible area by eliminating combustible vegetation and materials
can significantly reduce the likelihood of structure ignition. As a result, many wildfire mitigation programs and
emerging regulations increasingly emphasize the management of Zone 0 as a critical first line of defense for
improving structure survivability during wildfire events. Zone 0 regulations are in the process of being approved by
the Board of Forestry, however, the specific requirements for Zone 0 within the LRA are not finalized.
Structural hardening also plays a vital role in minimizing the potential for structure ignitions. Structural hardening
refers to steps a property owner may take to enhance the survivability of an existing structure that may not be up
to the current building or residential code standards for wildland areas. Homes survive wildfires through a
combination of vegetation management and maintenance, management of combustible materials on the property,
and installation and maintenance of fire- and ember-resistant construction materials. Hardening of the homes and
other structures to enhance survivability during wildfire would include retrofitting the most vulnerable home
features, including the following:
Although fire-resistant construction standards are mandatory for new buildings within the VHFHSZ, hardening
existing structures is voluntary. Adopting mandatory home hardening provisions in building and fire codes is
challenging because existing and nonconforming structures were typically approved and built to the codes in effect
at the time of construction. The problem persists, however, that a burning structure in a wildfire contributes to the
fire and presents a danger to nearby structures through radiant heat exposure and other structures downwind by
way of embers. Retrofits to existing structures can reduce fire risk, and some cost-sharing and grant programs are
available to offset costs.
8.2.1 Structural Ignitability Priority Recommendations
The following recommendations are provided to address structural ignitability. These recommendations are
anticipated to be refined/expanded during the CWPP process.
▪ Refine the City’s Landscape Manual to include Zone 0 within fuel modification zones following statewide adoption.
▪ Conduct structure inspections in tandem with existing defensible space inspection programs to educate
homeowners on the ignition resistance of their home.
▪ Require new development within the City Fire Suppression Zone to be constructed to ignition-resistant
standards of Chapter 5 of the CWUIC (formerly Chapter 7A standards).
▪ Prioritize structural hardening of critical facilities identified as being ember vulnerable from during the
field assessment
▪ Prioritize structural hardening of critical facilities that have been determined to have a high to very high
wildfire exposure score
▪ Encourage neighborhood-level structural retrofit programs to provide community scale benefits
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▪ Encourage the Firewise USA® program within the city to mobilize high-risk communities and improve
community-scale structural hardening efforts
▪ Encourage structural retrofits for structures through inspections or assessments, community education,
and grant funding opportunities.
▪ Update and promote a quick reference guide with high priority home hardening/defensible space tactics
that are potentially effective and cost-efficient.
8.3 Access and Evacuation
The City presents unique challenges for evacuation due to terrain, access constraints, limited escape routes for
some communities, and narrow/winding road networks in some cases. The City also experiences traffic due to a
high residential and visitor population.
Wildfire evacuation procedures in Carlsbad are coordinated through a multi-agency emergency management
framework that includes the City’s inter-department, inter-jurisdictional, and inter-agency emergency response
organization, regional alert and warning systems, and coordinated evacuation planning.
During significant wildfire incidents, the City may activate the City Emergency Operations Center (EOC), to coordinate
and support City-level emergency operations. Significantly, the EOC is not a command post and does not
control/direct field response units. The EOC brings together representatives from Senior City Leadership, the
Carlsbad Fire Department, Carlsbad Police Department, Public Works, and other relevant city departments to
support incident information sharing and intelligence sharing, coordinate resource requests and allocations, and
complete other necessary tasks. The EOC also coordinates with regional partners including the San Diego County
Office of Emergency Services and neighboring jurisdictions to ensure a unified response during large wildfire events.
San Diego County and the City maintain and operate a comprehensive Emergency Alert and Warning System. This
regionwide system includes Genasys ALERT, Genasys EVAC, and Genasys Protect. Emergency Alerts and Warnings,
such as evacuation notifications, are primarily distributed through Genasys ALERT https://www.alertsandiego.org/
en-us/preparedness/alertsandiego.html, the countywide emergency mass notification system. Genasys ALERT
sends alerts and warnings, including but not limited to evacuation warnings and evacuation orders, via phone call,
text message, and email to residents in impacted areas. Residents are encouraged to register their contact
information to ensure they receive alerts during emergencies.
The City also utilizes Genasys EVAC, a countywide evacuation management system used by Police and Fire
Departments to plan, conduct, and communicate emergency evacuations. Genasys EVAC is a data-driven
evacuation management system that allows emergency officials to create geographically defined evacuation zones
and deliver/disseminate targeted evacuation warnings and orders to specific neighborhoods. Emergency
notifications from Genasys EVAC are provided via Genasys Protect. (the public-facing interface of Genasys EVAC)
Through Genasys Protect, residents can view evacuation zone maps, track the status of evacuation orders or
warnings, and receive updates as conditions change.
Evacuations are typically issued in phases, beginning with Evacuation Warnings, which advise residents to prepare
to leave, followed by Evacuation Orders, which require immediate evacuation due to imminent safety risk. In some
instances, evacuation orders and warnings may be issued at the same time for different locations. During wildfire
incidents, evacuation zones may be established and road closures implemented to facilitate safe movement of
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residents away from threatened areas. Temporary Evacuation Points and/or Emergency Shelters may also be
established if needed.
As described in the City General Plan, evacuation route capacity in Carlsbad may be constrained by roadway design
limitations and existing traffic congestion, particularly during peak commute periods. Key constraints include two-
lane roadways with limited traffic capacity, as well as potential bottlenecks at major intersections, freeway
interchanges, and at-grade railroad crossings.
Routes with lower roadway capacity include Las Flores Drive, Levante Street, and Jefferson Street, which may
experience reduced evacuation efficiency due to their two-lane configuration. In addition, several major corridors
experience peak-hour congestion and reduced levels of service, including segments of Palomar Airport Road,
Cannon Road, and El Camino Real, particularly near interchanges with Interstate 5 and California State Route 78.
These areas represent potential evacuation bottlenecks during large-scale emergency events.
Evacuation concerns are heightened for communities identified as Single Entry/Single Exit neighborhoods, where
residents rely on a single roadway for both ingress and egress. As identified in the City’s General Plan, several of
these neighborhoods are located in close proximity to wildland or open space areas that may be susceptible to
wildfire. The limited access in these communities can create potential evacuation challenges during emergency
events, particularly if evacuation demand coincides with advancing fire conditions or if the primary access route
becomes compromised. As a result, these areas require careful consideration in emergency planning, including
early evacuation notifications, coordinated traffic management, and public preparedness efforts to ensure
residents can safely and efficiently evacuate if necessary.
As identified in the City’s General Plan, the City and police department maintains evacuation plans for wildland
preplan areas (See Figure 12). These plans identify specific regional evacuation protocols for wildfire evacuation.
8.3.1 Access and Evacuation Priority Recommendations
The following recommendations are provided to address access and evacuation within Carlsbad. These
recommendations are anticipated to be refined/expanded during the CWPP process.
▪ The city should develop wildfire preparation plans for the Poinsettia and Kelley Ranch regions.
▪ The city should require formal emergency response delay assessments for proposed traffic calming
devices, incorporating evidence-based delay estimates to assess cumulative impacts on response times.
▪ The city should identify and designate priority evacuation corridors within its Safety Element framework.
▪ As part of the CWPP, identify strategic roadsides to conduct vegetation management to prevent ignitions
and improve emergency access
▪ Conduct targeted outreach and education within single-access communities (e.g. Rancho Carlsbad,
Ranch Carrillo).
▪ Reevaluate and remap single-access communities as part of the CWPP, and update the General Plan, as
appropriate, to more accurately reflect evacuation constraints and wildfire risk.
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8.4 Water Supply and Infrastructure
Fire flow requirements in Carlsbad are established in accordance with the Insurance Services Office standards and
the applicable fire codes, which base required fire flow on factors such as building construction, occupancy, and
installed fire protection systems (e.g., automatic sprinklers). While the Carlsbad Municipal Water District generally
maintains adequate water supply and pressure for fire protection, the 2019 Potable Water Master Plan identified
several locations where fire flow capacity improvements are needed, including areas such as Robertson Ranch and
Quarry Creek, where capital improvement projects involving water main upsizing have been planned.
To address these localized capacity limitations and support future development, it is recommended that the
Carlsbad Municipal Water District continue to prioritize and implement planned water infrastructure upgrades
identified in the Water Master Plan, particularly those involving pipeline upsizing in areas with identified fire flow
constraints. Additionally, ongoing coordination between the City’s development review staff and the fire department
staff should continue to ensure that new development projects provide adequate fire hydrant spacing and fire flow
capacity consistent with applicable fire protection standards.
8.5 Fire Department Resources
The expansion of the Fire Suppression Zone and the corresponding increase in areas designated within the VHFHSZ
substantially increases the number of properties subject to wildfire mitigation requirements in Carlsbad. With
approximately 7,214 additional parcels and an estimated 12,500 structures now included, the City will be
responsible for conducting defensible space inspections and ensuring compliance with fuel modification and
vegetation management standards across a significantly larger area. This expanded responsibility is expected to
increase the workload associated with inspection, enforcement, and administrative oversight, indicating that the
Carlsbad Fire Department will likely require additional staffing or resources to maintain effective inspection
frequency and program implementation within the expanded wildfire hazard areas.
Given the significant increase in parcels and structures subject to defensible space and fuel modification
requirements, it is recommended that the Carlsbad Fire Department conduct a comprehensive staffing study to
evaluate the level of additional personnel needed to effectively implement inspection and enforcement activities
within the expanded wildfire hazard areas. The study should assess current inspection capacity, anticipated
workloads associated with the expanded VHFHSZ and Fire Suppression Zone, and the frequency of inspections
required to maintain compliance. The results of this analysis would help the City determine the appropriate level of
staffing and resources necessary to sustain an effective defensible space inspection program and ensure continued
wildfire risk reduction across the expanded area.
8.6 Community Education and Outreach
Residents, property owners, and local stakeholders play a critical role in reducing ignition potential, maintaining
defensible space, and preparing for safe evacuation. Building awareness, shared responsibility, and local capacity
not only strengthens individual preparedness but also enhances the collective resilience of the entire community.
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The CWPP will expand upon existing education and outreach initiatives by implementing a comprehensive, ongoing
strategy to engage the community.
▪ As part of the CWPP process, actively engage community members, neighborhood associations, and local
stakeholders to identify specific wildfire concerns, vulnerabilities, and priorities. Conduct public workshops,
surveys, and interactive mapping exercises to gather input on high-risk areas, evacuation challenges, and
preparedness needs.
▪ Utilize the CWPP process as an opportunity to enhance wildfire education, raise awareness about
defensible space, home hardening, and emergency planning.
▪ Increase community awareness and participation in Firewise USA® programs.
▪ Promote and support the development of community programs, such as CERT and Community Fire Watch,
to build an informed, proactive, and engaged community in wildfire preparedness and response
▪ Develop and distribute wildfire awareness materials (e.g., signage, QR codes) at popular recreation areas
to increase wildfire hazard awareness and reduce ignition risk.
▪ Conduct public outreach and education in communities where vegetation management projects are
proposed prior to initiating work.
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