Wildfire Hazard Assessment
Camarillo, California
Prepared for:
Prepared by:
TSS Consultants
March 11, 2024
Camarillo Wildfire Hazard Assessment
iii
FORWARD
This project has its roots in the responsibility of the City of Camarillo to keep its General Plan1 properly updated by conducting California Environmental Quality Act (“CEQA”)-compliant analyses needed to follow proper procedure for the update process. Within the context of this updating requirement, the City of Camarillo (“City”) engaged Rincon Consultants (“Rincon”) to conduct technical studies in support of updates to the Circulation and Safety Elements. As well as addressing the standard transportation issues associated with natural disaster preparedness and response, the scope of work for the City’s Plan included a focus on potential wildfire impacts. In order to conduct the technical studies associated with an assessment of wildfire hazard analysis Rincon retained TSS Consultants (“TSS”) a natural resource planning and management consulting firm, with in-depth experience in wildfire issues assessment and mitigation management.
In conducting the technical studies, and issuance of the results reported on herein, TSS was mindful of the full hierarchal set of client needs that was to be met and how the information in this report was to eventually be used. The principal considerations associated with this process included:
• Conducting project actions to the highest levels of professional performance expectations; • Specifically, conduct procedures and analyses that produce information to the performance standards set out in CEQA and its associated Guidelines; and; • Select the principal scientists on the basis of their ability to apply the process of professional judgement, again as laid out in the CEQA statute and guidelines.
To properly address the three considerations above TSS’ project team was headed by three principal scientists: Tad Mason, Steven Daus, and Barry Callenberger. Brief biographical sketches of these three individuals are presented in Addendum I to this report.
With respect to interpreting the information presented in this report a glossary of terms is included.
These terms will be identified in the text by a bold/italicized font. The term explanations have been formulated so that the reader has an understanding how they are to be interpreted within the wildfire assessment setting of this report.
GLOSSARY of TERMS
All terms included in the following list are to be interpreted solely within the context of their meaning in this report; Wildfire Hazard Risk Assessment-Camarillo, California These definitions may not to be applicable to any other situations that are not directly related to the analysis completed herein. These terms, upon their first usage in the report, will be indicated by bold italic font.
Adverse – Acting in opposition to a process or influence, e.g., a fire burning downhill is acting adversely to the influence of the slope and will advance more slowly than if it were advancing upslope.
1 City of Camarillo. 2004
Camarillo Wildfire Hazard Assessment
iv
Adverse Impact – A change in the conditions of elements of the setting in which an action has been implemented that is not consistent with the goals or objectives of either a project’s proponents or reasonably associated stakeholders.
Baseline Conditions – The full array of setting elements, defined in terms of its status or condition, in which a project takes place at a defined point in time prior to implementation of any project-related actions.
Bole Pruning – The removal of limbs from the bole of a tree.
Canopy Closure – A measure, usually defined in percentage terms, of the surface area covered over by a leafy overstory crown.
Catastrophic Wildfire Event – A wildfire event where the behavior is sufficiently severe so has to completely remove existing elements occupying a surface area. Examples would include complete removal of forest stands and residential structures.
Community – An aggregation of residential development that has a definable extent (or boundary) and observable community infrastructure (e.g., roads, utilities, community services centers).
Contextual Conditions – Surface feature or conditions that are present and define the context in which a project is located.
Convergence of Evidence – Working toward a decision through successive consideration of multivariate information. It is basically a “course correction” model where accuracy increases as more information is gathered and analyzed.
Core Project Study Area – The 12,608 acres that lie within the city limits of Camarillo, California.
Crosswalk – Typically, the linking of two different sets of data, or derived information, through an “if- then” procedure. In this particular study it involves linking vegetation types (which are typically described in floristic terms) with standard fuel models from which wildfire behavior can be predicted.
Crown – The layer of limb, twig, and leafy material constituting the top portion of a tree.
Cumulative Effects – Change influencing effects that are created when two, or more, individual actions interact to create effects that are different in nature and/or intensity than those when only a single action is taking place.
Cumulative Impacts – Changes to baseline conditions that are caused when cumulative effects are being generated.
Data – In general situations this term can be interpreted to mean facts and statistics collected together for reference or analysis. Where computer-aided analyses are a part of an assessment design an
Camarillo Wildfire Hazard Assessment
v
additional meaning could be the quantities, characters, or symbols on which operations are performed by a computer, being stored and transmitted in the form of electrical signals and recorded on magnetic, optical, or mechanical recording media.
Databases – Presentations of raw data, or derived information, that has a unifying theme. They are generally presented in hard-copy map formats or in digital formats. Digital databases utilized in multi- variable assessments associated with wildfire issues typically have the capability of being referenced to standard mapping or image geographic coordinate systems.
Deflection – The distance between a powerline and a surface condition that, in the event of involvement in a wildfire event, could determine the likelihood of “loss of function” damage risk.
Design/Build – Where future actions taken regarding the design, or implementation, of a project depends on what was learned in previous actions.
Desirable species – Species of plants whose treatment within the prescribed management described herein fulfills both the applicant’s goals and objectives pertaining to increased protection from adverse wildfire impacts and improving the ecological condition and functioning of the subject plant and animal species involved.
Diurnal Winds – Highly localized winds that respond to daily changes in surface temperatures and whose flow pattern is controlled by detailed topographic structure.
Ecological Functioning – The ability of setting conditions to support an aggregate of plant and animal species in sustainably (measured in successive generations) occupying a site.
Effect – The mechanistic influence that can result in a change in status or condition of setting elements.
Emergency Responders – The full set of emergency personnel providing assistance in response to a wildfire incident. Typically includes personnel providing fire, medical, and law enforcement services.
Empirical Evidence - Information that is acquired by direct observation or experimentation.
Extended Project Assessment Area (EPAA) – An additional 22,471-acre area that completely envelopes the CPSA established primarily to evaluate the potential movement of wildfire towards Camarillo city resources.
Extraordinary Winds – Wind patterns (including direction and velocities) that occur only occasionally but can be accompanied by significant adverse impacts.
Fire Season – Typically a seasonal period from April to October, where, in the project areas, the climate has average temperatures that are higher and humidity levels that are lower.
Floristic Nature – A manner of defining an aggregation of vegetation species that includes elements like species present, relative composition percentages, basic site requirements and flowering periods.
Camarillo Wildfire Hazard Assessment
vi
Fuel – Plant material available for combustion.
Fuel Bed – An aggregation of combustible fuels that is defined by its component materials, material sizes, physical structure, and continuity (or dis-continuities).
Full Project Assessment Area (FPAA) – The 35,079-acre area within which this assessment was completed. It is comprised of the area within the Camarillo City limits, referred to as the Core Project Study Area (“CPSA”), and lands in a peripheral area, referred to as the Extended Project Assessment Area (“EPAA”).
Gallery Formations – Tree-dominated vegetation types that border drainages.
Heightened Vulnerability – Where risk of adverse impacts from wildfire is at an elevated level.
Impact – The observable change in the state of a setting element as a result of an effect coming from the implementation of an action.
Influence – A measure of the mechanistic ability of an effect to create a change in the nature of a setting element or processes characterizing the setting.
Influence factor – A quantitative measure of the comparative degree of effect a specific ground condition has on wildfire behavior and its associated level of risk.
Information - Facts provided or learned about something or someone. In the science disciplines it is typically the results from an analysis of data.
Intensity (of an effect or impact) – The degree of the mechanistic ability of an effect to create a change in a setting element.
Interpretation Criteria – Specifically defined observations that lead to a conclusion.
Ladder Fuels – Materials in a multi-storied stand of vegetation that creates a continuous fuel bed from the surface to the overstory crown.
LANDFIRE – A wildfire behavior prediction model created through the Interagency Fuel Treatment Decision Support System program.
Layman Sourced – Observations made by individuals who would not be qualified to implement a professional judgment process but, nonetheless, warrant some measure of consideration.
Lop and Scatter – A treatment that cuts material removed for fuel reduction purposes into sizes that meet appropriate performance standards and is then distributed evenly over the surface of the treated area.
Camarillo Wildfire Hazard Assessment
vii
Loss of Function – A situation where a feature, or condition, has been created to perform a defined function but can no longer perform that function due to being involved in a wildfire event.
Maintenance Management – Vegetation management actions designed specifically to keep conditions created in prior management actions.
Managing Against – An approach to vegetation management that 1) defines individual plant species whose current influence in a particular area is not in alignment with management goals and objectives, and 2) implements specific actions to reduce, or even eliminate, that influence.
Managing For – An approach to vegetation management that 1) defines individual plant species whose influence in a particular area is in alignment with management goals and objectives, and 2) implements specific actions to augment that influence.
Multi-stage – An approach that is based on identifying a sub-area within a more general context using management defined selection criteria and then focusing resources on that sub-area.
Nature (of an effect or impact) – The specific mechanistic-related elements that have an observable capability to create change in a setting element.
Non-Fire Season – Typically a seasonal period from November to March, where, in the project areas, the climate has average temperatures that are lower and humidity levels that are higher.
Overstory – Another term for the crown area of forest or woodland formations. Typically it is defined by canopy closure percentages, thickness, height above the surface and average opening size.
Physical Conditions – The subset of setting conditions that have a physical presence and exert mechanistic influences based on its physical nature.
Prescriptive Guidance Materials – Laying out performance standards using measures that are not subject to interpretation. For example, in protecting riparian values California Forest Practice Rules require the proponent is required to retain at least 75 percent of the “overstory canopy” and if this performance result is not attained the proponent out of compliance.
Prevailing Winds – Winds that have definable and predictable patterns (typically direction and velocity measures) whose data are collected at official weather stations.
Professional Judgement – A decision situation where there is 1) a lack of empirical evidence upon which to justify the decision, and 2) the decision must be made by a discipline expert whose credibility for making the decision is based on their academic training, practical certifications, and direct experience with the subject material.
Reasonable Sphere of Impact – A subjective determination of the physical extent an effect resulting from implementing a project action can have.
Camarillo Wildfire Hazard Assessment
viii
Regular Maintenance Program – A management program designed to conserve conditions created through prior transition management action and is defined by specific vegetation management prescriptions and return intervals.
Sensitive Resources – Resources that have identified as having a combination of high intrinsic value and susceptibility to adverse impacts if involved in a wildfire event.
Setting – For this particular project situation, the setting in which the project is located, is comprised of the full array of wildfire-related features and conditions that have direct, or indirect, effects on wildfire behavior and it associated levels of hazard and risk.
Setting Elements – The individual feature or conditions comprising the overall setting that are 1) observably present, and 2) relate to wildfire issues.
Shaded Fuelbreak – A tract of land where there is an overstory of intermediate and dominant tree canopy, low quantities of “ladder fuels, and low-growing surface vegetation. The tree canopy has openings in it that are large enough to create fuel discontinuities and yet small enough to provide high relative time periods of full, or partial, shade at the ground level.
Site Quality – The ability of a ground area to provide physical habitat elements that allow for vegetation or animal species to occupy the area on a sustainable basis.
Standard Fuel Models – Industry standard models that link site characteristics to wildfire behavior. For the purposes of this study there were two primary categories of models, those based on the vegetation type occupying the surface and those that reflect the physical characteristics of the surface.
Subjective Guidance Materials – Materials comprised of guiding instructions that require an advanced level of familiarity with a management situation in order to make appropriate decisions. This is a situation where the concept of professional judgment can come into play.
Sward – Basically and area of ground covered by grass species (monocots) but realistically also involves the presence of low-growing broad-leafed species (dicots).
Transition Management – A management approach that involves implementing actions to change ground conditions from those that are less desirable (i.e. inconsistent with management’s goals and objectives) to those that are more desirable (i.e. more consistent with management’s goals and objectives).
Type Conversion – Complete removal of the physical manifestation, and thus the functioning, of one, or more, setting elements.
Vegetation Formation – A distinctly recognizable aggregation that is defined by a mappable extent, commonly observed plant species, and homogeneous plant species compositions and structures.
Camarillo Wildfire Hazard Assessment
ix
Vegetation Management Prescription – A detailed set of instructions for implementing vegetation management.
Wildfire Behavior – The aggregation of physical and mechanistic manifestations that an uncontrolled fire exhibits as it ignites and crosses a landscape. The principal elements include spread rates, manner of spread (surface travel or ember spread), flame lengths, fire intensity, residence time at a particular location, and within-structure behavior.
Wildfire Event – A discrete occurrence of un-controlled fire that has a defined start point (location and date/time), defined area of impact, and a defined period of evolution to the point of control.
Wildfire Hazard – Similar to the flood zone maps generated by the Federal Emergency Management Agency (FEMA), the California Fire Hazard Severity Zone (FHSZ) identifies where lands are described in terms of their likelihood of being involved in a wildfire event, and not specifically prescriptive of impacts. “Hazard” is based on the physical conditions that create a likelihood and expected fire behavior without considering mitigation measures such as home hardening, recent wildfire, or fuel reduction efforts.
Wildfire Hazard Level – The relative degree of likelihood that a wildfire event will take place at a subject location within either the Core Project Study Area (CPSA) or the Extended Project Study Area (EPSA).
Wildfire Risk – Risk is the potential damage a fire can do to the area under existing conditions, accounting for any modifications such as fuel reduction projects, defensible space, and ignition resistant building construction.
Wind Rose – A graphical portrayal of winds showing direction and other metadata typically present in annual and monthly summary formats.
Camarillo Wildfire Hazard Assessment
x
LIST of ABBREVIATIONS
AB Assembly Bill (California)
AMSL Above Mean Sea Level
APN Assessor’s Parcel Number
BOF California State Board of Forestry and Fire Protection CAL FIRE California Department of Forestry and Fire Protection Caltrans California Department of Transportation
Cal/VTP California Vegetation Treatment Program (California State Board of Forestry) CCR California Code of Regulations
CE Cumulative Effects
CEQA California Environmental Quality Act
CFPR California Forest Practice Rules
CPSA Core Project Study Area
DCP Data Collect Platform (California weather stations) EE Empirical Evidence
EPAA Extended Project Assessment Area
FHA Federal Highway Administration
FHSZ Fire Hazard Severity Zone
FPD Fire Protection District
FPAA Full Project Assessment Area
FRA Federal Responsibility Area
FRAP Fire and Resources Assessment Program
FS Fire Season
GESI Google Earth Satellite Imagery
HTEL High Tension Electrical Lines
IC Interpretation Criteria
ICS Incident Command System
IF Influencing Factor
IFTDSS Interagency Fuel Treatment Decision Support System LANDFIRE IFTDSS Wildfire Behavior Model
LOF Loss of Function
LRA Local Responsibility Area
MM Mitigation Measure
NOAA National Oceanic and Atmospheric Administration
NFS Non-Fire Season
OSFM California Office of the State Fire Marshal
PEIR Programmatic Environmental Impact Report
PRC Public Resources Code
PWP Public Works Program
RAWS Remote Automated Weather Stations
RCD Resource Conservation District
RPF Registered Professional Forester
SFB Shaded Fuel Break
SPR Standard Project Requirements
Camarillo Wildfire Hazard Assessment
xi
SRA State Responsibility Area
SFM Standard Fuel Model
TA Treatment Approach
TL Treatment Landscape
USDA/FS United States Department of Agriculture/Forest Service USF&WS United States Fish and Wildlife Service
USFS United States Forest Service
USGS United States Geological Survey
USDI United States Department of the Interior
USDI/BLM United States Department of the Interior/Bureau of Land Management USDI/NPS United States Department of the Interior/National Park Service VTR Vegetation Type-Related
WDB Wind Direction Bundles
VCFD Ventura County Fire Department
VMRX Vegetation Management Prescription
WFB Wildfire Behavior
WHL Wildfire Hazard Level
Camarillo Wildfire Hazard Assessment
xii
TABLE OF CONTENTS
EXECUTIVE SUMMARY ...................................................................................................................... 1 INTRODUCTION..................................................................................................................................... 2 Planning Environment in Which this Hazard Assessment has been Conducted ................................................................. 2 Jurisdictional Mandates And Authorities and Associated Regulatory Requirements ............................................................. 2 Level of Professionalism Employed in Conducting the Assessment ...................................................................................... 4 Current Status of the Technical Options Available for Use in the Assessment ...................................................................... 4 Initial and Subsequent Uses of the Assessment Results .......................................................................................................... 4 GENERAL SETTING .............................................................................................................................. 5 Project Assessment Area ........................................................................................................................................................... 5 General Climate ......................................................................................................................................................................... 5 ..................................................................................................................................................................................................... 8 Full Project Study Area Topography ....................................................................................................................................... 8 Emergency Response Apparatus .............................................................................................................................................. 8 Wildfire History ....................................................................................................................................................................... 10 ASSEMENT APPROACH AND METHODOLOGY ......................................................................... 13 Collection of Background Data and Information ................................................................................................................. 13 Identification of Specific Mapping and Predictive Modeling Procedures .......................................................................... 13 Identification of Data and Information to be Used as Inputs in the Analyses .................................................................... 14 Physical Terrain Conditions .................................................................................................................................................. 14 Regional Slopes ................................................................................................................................................................ 14 Aspect ................................................................................................................................................................................... 16 Vegetation Type Related Fuel Models .................................................................................................................................. 18 Natural Vegetation Within the FPAA .............................................................................................................................. 18 Relationship Between Vegetation Types/Land Uses and Fuel Models ............................................................................ 19 Vegetation-Related Fuel Models Used in the LANDFIRE Modeling Program ............................................................... 19 Fire Behavior Fuel Model 2 (FBMF 2) ....................................................................................................................... 20 Fire Behavior Fuel Model 5 (FBFM 5) ....................................................................................................................... 20 Fire Behavior Fuel Model 6 (FBFM 6) ....................................................................................................................... 21 Fire Behavior Fuel Model 8 (FBFM 8) ....................................................................................................................... 22 Fire Behavior Fuel Model 9 (FBFM 9) ....................................................................................................................... 22 Fire Behavior Fuel Model 10 (FBFM 10) ................................................................................................................... 23 Land Use Related Fuel Models ........................................................................................................................................ 24 Fire Behavior Fuel Model NB 1 .................................................................................................................................. 24 Fire Behavior Fuel Model NB 3 .................................................................................................................................. 24
Camarillo Wildfire Hazard Assessment
xiii
Fire Behavior Fuel Model NB 8 .................................................................................................................................. 24 Fire Behavior Fuel Model NB 9 .................................................................................................................................. 24 Distribution of Fuel Models Within the Camarillo FPAA .................................................................................................... 24 Environmental Influences ..................................................................................................................................................... 26 Prevailing Winds .............................................................................................................................................................. 27 Extraordinary Winds ........................................................................................................................................................ 31 SPECIAL RESOURCE SITUATIONS ................................................................................................ 32 Roads with Elevated Loss of Function Vulnerability ........................................................................................................... 32 Communities Vulnerable to Elevated Levels of Impacts from Wildfire ............................................................................. 35 High Tension Electrical Lines ................................................................................................................................................. 37 Vegetated Drainages ................................................................................................................................................................ 39 WILDFIRE HAZARD LEVEL DESIGNATIONS ............................................................................. 41 Assessment of Individual Setting Components ..................................................................................................................... 41 Terrain Slope ......................................................................................................................................................................... 42 Aspect ................................................................................................................................................................................... 43 Presence of Standard Fuel Models ........................................................................................................................................ 44 Prevailing Winds ................................................................................................................................................................... 46 Extraordinary Winds ............................................................................................................................................................. 46 Fire-Storm Generated Winds............................................................................................................................................ 46 Santa Ana Winds .............................................................................................................................................................. 47 Multiple Setting Components – Cumulative Effects ............................................................................................................. 47 Distribution of Wildfire Hazard Levels within the FPAA .................................................................................................... 48 INTERPRETATION OF RESULTS AND RECOMMENDATIONS ............................................... 50 Individual Setting Elements’ Influence on Wildfire Hazard Risk Levels ........................................................................... 51 Mapping Wildfire Hazard Levels for the FPAA ................................................................................................................... 51 Special Resource Situations .................................................................................................................................................... 51 Roads with Elevated Loss of Function Vulnerability ........................................................................................................... 52 Communities Vulnerable to Elevated Levels of Impacts from Wildfire ............................................................................... 52 High Tension Electrical Lines ............................................................................................................................................... 53 Vegetated Drainages ............................................................................................................................................................. 54 CONCLUSIONS AND RECOMMENDATIONS ................................................................................ 54 CONCLUSIONS AND RECOMMENDATIONS ................................................................................ 54 Regional Wildfire Hazard Risk Levels................................................................................................................................... 54 Regional Wildfire Hazard Risk Levels – Conclusions .......................................................................................................... 54
Camarillo Wildfire Hazard Assessment
xiv
Regional Wildfire Hazard Risk Levels – Recommendations ................................................................................................ 55 Recommendation: RWHR 01 – Multiphase Analysis ................................................................................................. 55 Recommendation: RWHR 02 – Assessment of the Multipliers Used ......................................................................... 56 Recommendation: RWHR 02 – Assess the Process for Evaluating Special Agricultural Situations .......................... 56 Reccomendation: RWHR 03 – Assess the Process for Evaluating Urban Land Uses ................................................. 56 Special Feature/Resource Conditions Situations................................................................................................................... 56 Wildfire Hazard and Risks Associated with Santa Ana Conditions ...................................................................................... 56 Wildfire Hazard and Risks Associated with Santa Ana Conditions - Conclusions .......................................................... 56 Wildfire Hazard and Risks Associated with Santa Ana Conditions - Recommendations ................................................ 56 Recommendation: SA 01 – Early Warning System ..................................................................................................... 56 Recommendation: SA 02 – Detailed Wildfire Movement Analysis for Elevated Terrain Zones ................................ 57 Wildfire Hazard Risks Associated with Agricultural Operations ......................................................................................... 57 Wildfire Hazard and Risks Associated with Agricultural Operations - Conclusions ....................................................... 57 Wildfire Hazard and Risks Associated with Agricultural Operations – Recommendations ............................................ 57 Recommendation: AO 01 ............................................................................................................................................ 57 Road Vulnerability to Wildfire-Caused Loss of Function .................................................................................................... 57 Road Vulnerability to Wildfire-Caused Loss of Function – Conclusions ........................................................................ 57 Road Vulnerability to Wildfire-Caused Loss of Function – Recommendations .............................................................. 57 Recommendation: LOF 01 – Conduct a Focused Assessment for Vulnerable Roads ................................................. 57 At Risk Communities – Those With Elevated Vulnerability to Wildfire .............................................................................. 58 Communities with Elevated Vulnerability to Wildfire – Conclusions ............................................................................. 58 Communities with Elevated Vulnerability to Wildfire - Recommendations .................................................................... 58 Recommendation: ARC 01 – Conduct a Focused Assessment for Vulnerable Roads ................................................ 58 Vegetated Drainages ............................................................................................................................................................. 58 Vegetated Drainages – Conclusions ................................................................................................................................. 58 Vegetated Drainages - Recommendations ........................................................................................................................ 59 Recommendation: WD 01 – Conduct a More Detailed Fuel Model Assessment ........................................................ 59 Recommendation: WD 02 – Initiate Collaborative Efforts with Regard to Mitigation ............................................... 59 REFERENCES ........................................................................................................................................ 60
Camarillo Wildfire Hazard Assessment
xv
LIST OF FIGURES
Figure 1. Core Project Study Area and Full Project Assessment Area ....................................................... 6 Figure 2. Graphical Presentations of Monthly High and Low Temperatures. ............................................ 7 Figure 3. Typical Annual Rainfall Pattern for Camarillo ........................................................................... 8 Figure 4. Distribution of Elevation Classes Within the Full Project Assessment Area .............................. 9 Figure 5. Potentially Involved Ventura County Fire Department Fire Stations. ........................................ 9 Figure 6. 2017 Wildfire Incidents Within the Project’s Region . ............................................................ 11 Figure 7. 100-year Wildfire History for the FPAA and Surrounding Region .......................................... 12 Figure 8. Slope Gradient Classes, Expressed in Degrees, Within the FPAA. .......................................... 15 Figure 9. Geographic Distribution of Aspects 9n the FPAA .................................................................... 17 Figure 10. Example 0f Shrub/Grass Vegetation Included in the FBFM 2 Fuel Model ............................ 20 Figure 11. FBFM 5 Shrub Layer Example Following a Fire .................................................................... 21 Figure 12. Surface and Ladder Fuels Conditions Example for the FBFM 9 Fuel Model ......................... 23 Figure 13. Distribution of Fuel Models Within the Camarillo FPAA ...................................................... 25 Figure 14. Monthly Wind Speed Data for Camarillo, CA ........................................................................ 26 Figure 15. Locations of Weather Stations Providing Data for Use in the Assessment ............................ 28 Figure 16. Graphical Presentation of Prevailing Wind Directions for Camarillo, CA. ............................ 29 Figure 17. Non-Fire Season Wind Directions Associated with the Three Weather Stations ................... 30 Figure 18. Fire Season Wind Directions Associated with the Three Weather Stations ........................... 30 Figure 19. Possible Movement Patterns of Winds Under Santa Ana Conditions ..................................... 31 Figure 20. Named Roads Addressed in the Wildfire Hazard/Risk Assessment ....................................... 33 Figure 21. Road Segments Addressed in the Vulnerability Assessment .................................................. 34 Figure 22. Seven Locations Identified as Communities With Elevated Vulnerability ............................. 36 Figure 23. Enlargement of One Community With an Elevated Vulnerability to Wildfire ....................... 36 Figure 24. Location of High Tension Electrical Line System Within the FPAA ..................................... 38 Figure 25. Enlarged View of a Portion of the High Tension Electrical Line ........................................... 39 Figure 26. Distribution of Vegetated Drainages Within the FPAA .......................................................... 40 Figure 27. Enlarged View of a Vegetated Drainage ................................................................................. 41 Figure 28. Distribution of Wildfire Hazard Levels Within the FPAA ..................................................... 49 Figure 29. High Tension Electrical Transmission Line Corridors Within the FPAA .............................. 53
Camarillo Wildfire Hazard Assessment
xvi
LIST of TABLES
Table 1. Monthly Temperature Averages for the Full Project Assessment Area ........................... 7 Table 2. Ventura County Fire DEPArtment Stations Providing Wildfire Response in the FPAA10 Table 3. Slope Gradient Classes Within the FPAA ...................................................................... 16 Table 4. Aspect Class Acreage Within the EPAA. ....................................................................... 17 Table 5. Specifications for FBMF 2 Fuel Model .......................................................................... 20 Table 6. Specifications for FBMF 5 Fuel Model .......................................................................... 21 Table 7. Specifications for FBFM 6 Fuel Model .......................................................................... 22 Table 8. Specifications for FBFM 8 Fuel Model .......................................................................... 22 Table 9. Specifications for FBFM 9 Fuel Model .......................................................................... 23 Table 10. Specifications for FBFM 10 Fuel Model ...................................................................... 24 Table 11. Portions of the Camarillo FPAA Occupied by the Mapped Fuel Models .................... 25 Table 12. Wind-Related Information Provided Three Weather Stations ...................................... 28 Table 13. Results of the Road Vulnerability Assessment ............................................................. 34 Table 14. Key Data for Communities at Elevated Risk ................................................................ 37 Table 15. Categories of Aspect Derived From the Digital Database ............................................ 43 Table 16. Wildfire Hazard Risk Levels Acreage Data ................................................................. 50
LIST OF APPENDICES
Addendum I. BioSketches of Principal Scientists
Addendum II. IFTDSS Reports
Addendum III. Road Vulnerability Study Results
Wildfire Hazard Risk Assessment
Camarillo, California
EXECUTIVE SUMMARY
A wildfire hazard assessment was completed to provide technical support for a CEQA-compliant revision of the Safety Element of the City of Camarillo’s general plan. The objective was to deliver a map, along with supporting analysis result and digital products, of the wildfire hazard situation in a 35,079-acre study area (referred to as the full project assessment area, or FPAA). This study area encompassed the 12,608 acres within Camarillo’s city limits (the core project assessment area, or CPAA) and an additional 22,471-acre area around the perimeter of the CPAA (referred to as the extended project assessment area, or EPAA).
Wildfire hazard level, or the likelihood that a wildfire could occur in a subject area, is a product of a set of ground conditions characterizing an area and their influence on wildfire behavior (WFB). The ground conditions selected as the principal influences on WFB in the Camarillo area were terrain slope, terrain aspect, winds (both prevailing and extraordinary), the presence of standard fuel models (SFM). The SFMs selected for use in this assessment followed the work of Scott and Burgan 2 and the assessment
process was supported by the running of an IFTDSS LANDFIRE wildfire behavior prediction model3.
Wildfire hazard was broken out into three levels and the acreages mapped for the FPAA is shown in the table below. The analysis indicated that the majority of the “Medium” and “High” WHLs were associated with the band of elevated terrain surrounding the City (primarily located in the EPAA) and, conversely, the “Low” WHL category predominated within the CPAA.
WHL
Surface Areas of WHL Levels
Acres Proportion
Low (1) 21,187 60.4%
Medium (2) 4,045 11.5%
High (3) 9,847 28.1%
Total Acres 35,079
Although primarily scoped as a regional effort, consideration was also given to more site-specific special feature/resource conditions situations. These special conditions included:
• Road vulnerability to loss of function (LOF) during a wildfire event; • Isolated communities with elevated vulnerabilities to wildfire; • High tension electrical transmission lines, and;
• Vegetated drainages.
2 Scott. Joe H. and R.E. Burgan. June, 2005
3 IFTDSS. January 3, 2023
Camarillo Wildfire Hazard Assessment
2 Each of the special feature/resource conditions situations were mapped and attributed with area and location metadata but were not the subject of in-depth impact assessment due to project scope limitations.
The conclusions drawn and recommendations made addressed primarily the analysis process employed and the actions that could be taken to assist in WHL reduction efforts.
INTRODUCTION
Planning Environment in Which this Hazard Assessment has been Conducted.
This assessment has been completed in a planning environment with a range of elements that include the following:
• Jurisdictional mandates and authorities and associated regulatory requirements; • Level of professionalism employed in conducting the assessment; • Current status of the technical options available for use in the assessment, and; • Initial and subsequent uses of the assessment results.
Following are sections with brief discussions regarding each of the four elements above. How these considerations are reflected in the design of the approach, collection of data and information, analysis of these data or information, drawing of conclusions, and making of recommendations is presented in a following section entitled “Assessment Approach and Methodology”.
Jurisdictional Mandates And Authorities and Associated Regulatory Requirements The principal entities that have legal mandates and authorities for wildfire issues within the project assessment area include:
• The City of Camarillo;
• Ventura County/Ventura County Fire Department (VCFD); • The Office of the State Fire Marshal (OSFM), and;
• The California Department of Forestry and Fire Protection (CAL FIRE).
The City of Camarillo performs three principal functions: Formulating and institutionalizing wildfire- related policy, acting as the Lead Agency for California Environmental Quality Act (CEQA) 4 and 5 -
related procedures, and as a party in the emergency response services provision agreement with the VCFD. Ventura County’s roles include setting overall policy with respect to wildfire issues and working through the VCFD to establish wildfire emergency response practices and regulatory enforcement. The OSFM’s primary responsibilities include developing polices for wildfire planning and emergency response, assisting with wildfire planning, and enforcing regulations (such as Section 4900 of the State’s Fire Code). CAL FIRE’s primary roles include enforcement of state wide rules and regulations and assistance with wildfire planning and pre-incident preparation activities.
4 13 PRC §§ 21000-21177.
5 14 CCR Division 6, Chapter 3, §§ 1500-15387 and Appendices A-K.
Camarillo Wildfire Hazard Assessment
3 It must be noted that there are two existing statewide systems of categorizing lands based on 1) initial response jurisdictional responsibilities, and 2) their relative level of fire hazard severity. Compliance with these standard methods was incorporated into this assessment.
In California there are three categories of initial response responsibilities: State Responsibility Areas (SRA), Local Area Responsibility (LRA), and Federal Responsibility Areas (FRA). The system was developed under the sponsorship of the Office of the State Fire Marshall (“OSFM”) and is used by CAL FIRE as one of its core sources of information in their initial response and mitigation planning processes.
A core deliverable from completing this assessment is answering a very basic question:
“What is the likelihood that a wildfire event will occur at any given location, most importantly throughout the Core Project Assessment Area (CPAA), but also within the Extended Project Assessment Area (EPAA)?”
Primary guidance for answering this question can be found in programmatic material developed by the California State Board of Forestry (“BOF”) and California Department of Forestry and Fire Protections’ (“CAL FIRE”). This material draws the distinction between what constitutes a wildfire hazard and wildfire risk
6. The full definitions of these terms are included in the Glossary, but basically “hazard” level relates to the likelihood that a wildfire event will occur at a given location and “risk” relates more to the nature and intensity of the impacts resulting from being involved in a wildfire event that includes both suppression aspects and pre-emptive mitigating management.
The primary purpose behind conducting this wildfire assessment is to provide information to personnel conducting regional-scale wildfire hazard-related planning in the Camarillo area. The principal deliverables include a geo-referenceable map, and associated digital database, of locations characterized by their differing wildfire hazard levels (”WHL”). The nature of the levels defined in this Project basically reflect those in the OSFM’s Fire Hazard Severity Zone (“FHSZ”) program 7, but the State’s
process used input variables more suited to its state-wide application, resulted in differing implementation opportunities than would be reasonable in the localized area addressed in this assessment, and is based on mapping specifications, primarily minimum mapping area, that indicated a potential for serious constraints on the utility of the results in the Camarillo situation.
However, along with the production of the primary deliverable package consideration of other aspects entered into the design and implementation of the study. These other aspects were expressed in considerations regarding how best to take the information appropriate to the regional scale and use it to guide:
• Subsequent studies focused on subjects and areas requiring a greater level of information regarding site characteristics than is possible with the regional level analysis reported on herein, and;
• Identifying appropriate site-specific management actions that, when implemented, would lower the currently determined wildfire hazard levels.
6 OSFM. January, 15, 2023.
7 ibid.
Camarillo Wildfire Hazard Assessment
4 A comparative examination of the mapping specifications and information content of the input variables characterizing the state-wide FHSZ system led to the conclusion that the goals and objectives of the Camarillo assessment would not be met by simply adopting the FHSZ’ existing map products and methodologies. Three specific goal- and objectives-related aspects led to this decision to design an approach different than that of the currently existing FHSZ procedure:
• The 2-kilometer (>800 acres) minimum mapping area base employed in the FHSZ system would not provide an adequate information base to utilize the results for guiding more detailed, analyses in a multi-stage type of approach.
• Lack of input variables that led to a model output that clearly described how wildfire physically crossed a landscape to a certain location and what would be its nature be upon the arrival, and; • Did not lead to an understanding of what actions to take in the field to reduce the potential for, and nature of, adverse effects.
Level of Professionalism Employed in Conducting the Assessment The ultimate use of the results of this assessment is providing technical support for the update of the Safety Element of the City’s General Plan. This update will involve CEQA-compliant impact studies and the conduct of these studies, and presentation of results, must meet CEQA’s performance standards.
One key to this compliance is to have the supporting technical studies be completed under the guidance of discipline specialists who are capable of providing expert testimony in support of their findings, conclusion, and recommendations. The TSS project team members directing the conduct of this assessment comply with this through each member’s academic training, certification, and experience.
Brief biographical sketches of the principal scientist involved in this assessment can be found in Addendum I to this report.
Current Status of the Technical Options Available for Use in the Assessment One keystone of preparing a robust defensible technical report is to assure the assessment procedures meet those that are compliant with industry standard measures that are in place at the time the work was performed. Proper research in, and professional familiarity with, the disciplines involved is designed to assure that the procedures employed are 1) appropriate to the assessment procedures being used, 2) currently available for use, and 3) have a “track record” of use over a sufficient period of time to prove its acceptability. In the design and implementation of this assessment the industry standard procedures employed included:
• Interpretation of remotely-sensed imagery, by suitably trained and experienced personnel, to provide empirical data about ground conditions;
• Use of professional judgement where empirical data is lacking or insufficient; • Use of a convergence of evidence decision procedure when working in multi-variable data input situations, and:
• Adoption of existing methodologies or products that are proven and appropriate to the goals and objectives of this Project.
Initial and Subsequent Uses of the Assessment Results
The set of immediate goals and objectives is focused on equipping the City and County planners and policy makers with current, and robust, information and standardized analysis tools that can be modified to meet local needs. The information can be used to support CEQA processes as it was generated in compliance with CEQA standards of performance, and to support the policy updating process. The
Camarillo Wildfire Hazard Assessment
5 combination of current information and adaptable analysis procedures represent key elements in planning on a strategic level.
However, there is another consideration that needs to remain “in the frame”; how can the information and analysis procedures be used to support operations planning and practices. This aspect is discussed in the concluding sections of this report.
GENERAL SETTING
Elements of the project’s setting that are pertinent to an assessment of wildfire hazard risk (WHL) are identified and briefly discussed in the sections immediately following. Greater detail regarding exactly how they relate, in terms of influence on the varying levels of WHL, are presented in later sections.
Project Assessment Area
The 35,079-acre Full Project Assessment Area (“FPAA”) addressed in this study (shown in Figure 1), is actually comprised, as previously described, of two distinct study areas:
• Core Project Assessment Area (“CPAA”). This is an area that is comprised of the 12,608 acres within the city limits of Camarillo, and;
• Extended Project Assessment Area (“EPAA”). As wildfire is a highly mobile phenomenon it is essential to address how it can approach the CPAA from a location outside of its boundaries. In order to properly assess this aspect, the CPAA was augmented with an additional 22,471 acres around the perimeter of the CPA. In Figure 1, below, the CPAA is defined by the narrow yellow boundary line and limits of the FPAA (the CPAA and perimeter EPAA) by the thicker cyan line.
The CPAA is the surface area within which wildfire hazard-related conditions will be mapped and analyzed with respect to 1) designating comparative levels of wildfire hazard throughout the study area, 2) identifying the potential patterns of fire-front movement within the CPAA, 3) identifying feature/conditions-specific vulnerabilities should a wildfire event occur, and 4) potential wildfire hazard mitigating actions that can be implemented. Feature/condition mapping and analysis will be conducted within the EPAA in order to 1) identify surface conditions exerting influence over wildfire’s behavioral nature and 2) the movement of the fire front as it approaches the boundaries of the CPAA.
General Climate
The patterns of temperature and precipitation for the Camarillo project are typical of sites with similar latitudes and elevations on the near-coast Oxnard plain and surrounding transverse mountain ridge- intermountain basin of the Santa Monica Mountain system. The combination of the average annual total rainfall of 7.37 inches, rainfall pattern, and temperature regimes qualifies the area as either a cold or hot (depending of micro-topographic situation) semi-arid environment
8. 8 Peel et. al.
Camarillo Wildfire Hazard Assessment
6 Monthly summaries for high and low temperatures are presented in Table 19 and Figure 210, below.
Figure 2 does show the notable correspondence between higher temperatures and the months in the latter part of the fire season.
Precipitation is primarily in the form of rainfall, but fog condensation can occur in the lower elevation portions of the EPAA. The annual precipitation amount distribution (in inches) is shown in Figure 3.
Notable in this figure is the very low monthly totals within the April-to-September fire season.
Figure 1. Core Project Study Area and Full Project Assessment Area
9 WorldClimate.com. 2022.
10 Weather spark. April 4, 2023.
Camarillo Wildfire Hazard Assessment
7 Table 1. Monthly Temperature Averages for the Full Project Assessment Area
Figure 2. Graphical Presentations of Monthly High and Low Temperatures.
Camarillo Wildfire Hazard Assessment
8 Figure 3. Typical Annual Rainfall Pattern for Camarillo
Full Project Study Area Topography
The City lies in a broad 7.6-mile by 3.4-mile basin with a central west-to-east bearing of 79º. The floor slopes up to an elevation of ~210’, above mean sea level (AMSL) on the northwest edge of the basin, at, southeast to an elevation of 114’ AMSL at the southeast edge. With respect to the encircling elevated terrain the northwest bloc has a maximum elevation of ~870’AMSL; the northeastern bloc a maximum of ~1,000’ AMSL; and the southeastern chain a maximum of ~1,600’ AMSL. A greater sense of the slope class and aspect patterns characterizing FPAA can be gained by examining Figure 4.
Emergency Response Apparatus
For Incident Command System (ICS) Type 5 and 4 wildfire incidents11 occurring within the FPAA the Ventura County Fire Department (“VCFD”) has primary responsibility for first response. Higher order incidents implementing a multi-agency incident command effort, through cooperative agreements, would involve resources from other local fire protection districts (FPDs) and CAL FIRE. Research has shown that, within a reasonable distance, there are no dispatch stations operated solely by CAL FIRE or any federal agency.
11 USDI/NPS. February 13, 2017
Camarillo Wildfire Hazard Assessment
9 Figure 4. Distribution of Elevation Classes Within the Full Project Assessment Area
The location of VCFD fire stations (with the exception of the headquarters offices), that are either 1) within the FPAA, or 2) within a reasonable response distance from the FPAA, are shown in Figure 5.
Additional details, including the station numbers, addresses and phone numbers are presented in Table
2. Figure 5. Potentially Involved Ventura County Fire Department Fire Stations.
Camarillo Wildfire Hazard Assessment
10 Two stations, 35 and 40, have been broken out in the table as they are of special interest. They are located outside of the EPAA and generally would not be considered as potential sources for emergency wildfire response. However, these stations are notable as they are strategically located on potential pathways for Santa Ana wind-driven wildfires to approach the City from the east. Should a Santa Ana wind-driven event occur close cooperation with staff at these stations would be essential. A more detailed discussion of Santa Ana conditions is presented in the extraordinary winds section of this report.
Table 2. Ventura County Fire Department Stations Providing Wildfire Response in the FPAA
Wildfire History
Knowledge of where, and when, in the past wildfire has occurred within Camarillo’s regional setting does provide important information regarding the likelihood of it re-occurring within the FPAA.
Analysis of mapped past wildfire occurrences builds a basic understanding of the combination of setting conditions that has a high likelihood of supporting future occurrences. However, simply knowing the occurrence pattern does not provide the type of direct understanding of the mechanistic processes (basically the “why” does the fire occur) necessary for an appropriate assessment within Camarillo’s planning situation.
Following are two figures showing the historical occurrence patterns; The first, Figure 6 for the recent (from 2013 to the present) large surface area fires within the general project area, and the second, Figure 7, for a for fires dating from 1939 to 2022.
Agency Station Location
CAL FIRE All CAL FIRE operations are in conjunction with stations operated by Ventura County Fire Department
Ventura County Fire Headquarters 165 Durley Rd. Camarillo, CA. 93010 (805) 389-9710
Ventura County Fire 50 189 S. Las Posas Rd. Camarillo, CA. 93010 (805) 371-1111 ext. 50
Ventura County Fire 51 3302 Turnout Park Cr. Oxnard, CA. 93030 (805) 371-1111 ext. 51
Ventura County Fire 52 5353 Santa Rosa Rd. Camarillo, CA. 93010 (805) 371-1111 ext. 52
Ventura County Fire 54 2160 Pickwick Dr. Camarillo, CA. 93010 (805) 371-1111 ext. 54
Ventura County Fire 55 403 Valley Vista Dr. Camarillo, CA 93010 (805) 371-1111 ext. 55
Ventura County Fire 57 3356 Somis Dr. Box 347, Somis, CA 93066 (805) 371-1111 ext. 57
Ventura County Fire 35 751 Mitchell Rad Newbury Park, CA. 91320 (805) 371-1111 ext. 35
Ventura County Fire 40 4185 Cedar Springs Rd. Moorpark CA. 93021 (805) 371-1111 ext.40
Camarillo Wildfire Hazard Assessment
11 The most recent large wildfire events, with proximity to the FPAA, all occurred in December of 201712:
• Thomas impacting 281,893 acres;
• Creek impacting 15,619 acres;
• Rye impacting 6,049 acres, and;
• Skirball impacting 422 acres.
The locations of these wildfires, relative to the FPAA, are shown in Figure 6, below.
Figure 6. 2017 Wildfire Incidents Within the Project’s Region
Perhaps more informative, with regard to the likelihood of wildfire impacting the FPAA, is the map overlay shown in Figure 7. This figure shows all of the fires, of recordable size, that have occurred in the area 1939, and clearly shows:
• A very high correlation between wildfire and the mountainous areas, and; • A very low occurrence of wildfire in the intermountain valleys and basins.
12 CAL FIRE. October 24, 2022.
Camarillo Wildfire Hazard Assessment
12 In Figure 7 the Camarillo FPAA boundary is shown by the broad red line. The individually outlined and shaded polygons portray the areas of impact of each recorded wildfire event. Although this robust set of data does show where wildfire has occurred in the past, and consequentially gives an indication of where it will most likely occur again, the data lacks the type of mechanistic information that relates directly to the surface conditions that will enable wildfire ignition, and determine the manner in which it will travel across the landscape, for arrival at a location of interest.
Figure 7. 100-year Wildfire History for the FPAA and Surrounding Region
Thus, it is more important to know accurately what the current fuels situations are at subject locations because this knowledge will enable better prediction of wildfire’s impacting behavior.
It must be noted, primarily from interpretation of the information in Figure 7, that wildfire is a much more common occurrence in the areas with a combination of wildland and elevated-terrain conditions.
An important part of this analysis will 1) address the relative positions of the CPSA and these area with higher expectation of a wildfire event occurring, 2) determine the wind and slope influences over moving wildfire fire from these areas toward the CPSA.
Camarillo Wildfire Hazard Assessment
13 ASSEMENT APPROACH and METHODOLOGY
The following industry-standard approaches and analysis methodologies will be used 1) in generating the appropriate surface condition databases and 2) in conducting the WHL identification. The approach and analysis activities will include:
• Identifying, and gathering, currently available literature and databases that can provide input data and information specific to:
o The generation of WHL designations for a regional-type assessment, and, o Assessing the mechanistic processes that resulted in adverse effects on special interest features or conditions;
• Identification of specific mapping and predictive modeling procedures • Identification of data and information to be used in the selected mapping and predictive modeling procedures
• Prepare the databases of setting conditions to be used in the PFAA-wide WHL designation and identification/analysis of wildfire’s effect on special resource situations Collection of Background Data and Information
This first activity will be conducted in three phases, 1) collecting existing data and information pertinent to a wildfire hazard assessment in the Camarillo environment, 2) conducting a data/information gap assessment, and 3) collecting the additional empirical data, or information, needed. This effort will focus on those data and information that define the nature and condition of individual environmental setting elements that have been determined to have direct and significant levels of influence on wildfire behavior and their associated wildfire hazard levels. The first phase of the collection of data and information employed two industry standard procedures, internet research and personal contacts. The third phase was conducted primarily by interpretation of satellite imagery by a trained and experienced remote sensing expert.
Identification of Specific Mapping and Predictive Modeling Procedures The primary mapping approach will employ interpretation of Google Earth Pro13 by an appropriately trained and experienced image analyst. Map products and metadata generated through this interpretation process will be produced in .kmz format; a digital file format that is compatible for use with current industry standard geographical information systems (“GIS") analysis packages.
The wildfire behavior prediction modeling was conducted using the IFTDSS - LANDFIRE 14 planning
assistance package. This package produced two basic groupings of results for the FPAA:
• Defining elements of wildfire behavior, and
• Setting condition databases that were used in the wildfire behavior modeling The full LANDFIRE reports are presented in Addendum II to this report.
The final products of the assessment (WHL designations and mapping and special resource situations) were then generated using a professional judgement-driven, convergence of evidence decision model
13 Google Earth Pro. Version 7.3.6.9345. December 29, 2022. 14 USDI/Interagency Fuel Treatment Decision Support System. January 3, 2023.
Camarillo Wildfire Hazard Assessment
14 Identification of Data and Information to be Used as Inputs in the Analyses The next step was to identify the specific setting elements that were to be considered in the analyses that comprised the assessment. These elements had to 1) have a direct and significant influence on wildfire behavior and 2) an observable mechanistic process by which the wildfire behavior was actually influenced (for further details see the Glossary and Addendum III Road Vulnerability Study Results).
Through consideration a combination of the 1) results of an initial examination of the FPAA via interpretation of the GESI and 2) professional experience, three physical surface conditions and two environmental conditions were identified as the primary contributors to wildfire behavior and associated hazard levels:
• Physical Terrain Conditions
o Regional slopes;
o Aspect, and;
o Vegetation type-related fuel models.
• Environmental Influences
o Prevailing winds, and;
o Extraordinary winds
Physical Terrain Conditions
The type of influence these setting elements have on wildfire behavior is considered to be static in nature; meaning unchangeable within the foreseeable future. For example, changes in regional terrain slope can be measured only over passage of geological time and over the 50-to-100-year planning horizon would be expected to have an unchanging influence.
Regional Slopes
The FPAA is comprised of a broad central basin, within which Camarillo is situated. As shown in Figure 8 15, there are a range of slope gradient classes forming a “horseshoe” of elevated terrain on the northern, eastern and southern basin boundaries. The central basin is characterized by slopes ranging from 0% to 11%, the foothill areas by slopes up to 22%, and the elevated terrain a complex mosaic of slopes ranging from 22% up to 75%. Figure 8 shows the distribution of slope class polygons, with the slope expressed in degrees, contained within the area of the digital database “clipped” to the FPAA. It is clear that this visual product would be difficult to employ in the more general planning application required due to the large number, and relatively small size, of the individual polygons generated in the LANDFIRE process.
As such, the “raw” polygonal data will be a delivered as a set of kmz-format digital files enabling subsequent uses in GIS procedures that can handle that level of detail.
15 IFTDSS. January 3, 2023
Camarillo Wildfire Hazard Assessment
15 Figure 8. Slope Gradient Classes, Expressed in Degrees, Within the FPAA.
In an effort to simplify the regional
planning application effort the 11 slope gradient classes contained in the digital database were lumped into three categories as shown in Table 3. Note that the digital database classes shown in Table 3 have slope values presented in degrees and since terrain slope percentage is more commonly used in forestry and wildfire situations, Table 3 shows the slope class in, first, its degree value but then also in a slope percentage value.
The data in Table 3 has been color coded to emphasize association with regulatory measures. The light- green shading indicates classes that correspond to terrain with slopes between 0% and 10% which identify lands that are flat-to-gently sloping (and less of a focus of regulatory constraints on field practices); the yellow shading indicates moderately sloped land, and the light-orange shading lands that are considered steep, where constraints on management practices (e.g., use of heavy equipment) are typically encountered in regulations.
Focusing attention on the last column it can be seen that:
• Over 62 percent of the lands in the EPAA are considered non- or gently-sloped; • Almost 90 percent is a combination of gently- and moderately-sloped terrain, and; • Only 10 percent considered as steep terrain.
Furthermore, when adding in consideration of the locations of the City and FPAA boundaries it is clear that almost the entirety of the steep terrain is outside of the City boundary. These slope-related setting conditions will have a significant influence on wildfire behavior, and associated WHL levels, within the FPAA.
Camarillo Wildfire Hazard Assessment
16 Table 3. Slope Gradient Classes Within the FPAA
Aspect
Aspect, or the direction in which terrain is facing, is important as it has an effect on the vegetation (and associated fuel models) that are present. In the EPAA the north and easterly facing slopes are typically higher in moisture regimes (precipitation) and cooler. The vegetation associations occupying these more mesic sites generally have the same species compositions but greater overall densities and stand heights, and more robust gallery formation along the drainages. Figure 916 shows the geographical distribution of the aspects within the EPAA.
16 IFTDSS. January 3, 2023.
Terrain Description
Classes: (degrees / %)
Occupation of FPAA Surface Area
Acres % Cum %
0 / 0% 8,499 24.2 24.2
0-5 / 0%-11.1% 13,291 37.9 62.1
5-10 / 11.2%-22.2% 3,856 11.0 73.1
10-15 / 22.2%-33.3% 3,015 8.6 81.7
15-20 / 33.3%-44.5% 2,600 7.4 89.1
20-25 / 44.5%-55.6% 1,994 5.7 94.8
25-30 / 55.6%-66.7% 1,183 3.4 98.2
30-35 / 66.7%-77.8% 507 1.4 99.6
35-40 / 77.8%-88.9% 120 0.3 99.9
40-45 / 88.9%-100% 12 >0.10 ~100.0
>45% 1 >0.10 ~100.0
Total Acreage 35,079
Camarillo Wildfire Hazard Assessment
17 Figure 9. Geographic Distribution of Aspects 9n the FPAA
Table 4. Aspect Class Acreage Within the EPAA.
Category Descriptions Occupation of FPA Surface Area
General Bearing Category Percentage Acres
Flat n/a 50.2% 17,618
N 0 7.5% 2,612
NE 1-89 4.5% 1,579
E 90 3.5% 1,228
SE 91-179 5.8% 2,026
S 180 9.2% 3,226
SW 181-269 6.3% 2,197
W 270 6.0% 2,100
NW 271-359 7.1% 2,493
Total Acreage 35,079
Further analysis of the topographic situation in which the two project areas (CPAA and FPAA) are situated shows that the CPAA is, in almost all instances, located downslope of the wildland/elevated terrain condition. Considering only the influence of slope on wildfire movement this will exert an influence that results in less rapid fire front movement (with an associated increase in the ability to bring the wildfire under control).
Camarillo Wildfire Hazard Assessment
18 Vegetation Type Related Fuel Models
Although a comprehensive knowledge of the vegetation types is important to wildfire issues it is not as important when predicting wildfire behavior. Vegetation type information is employed in various analyses primarily because the databases have been developed over centuries of science-based observations and are an ingrained industry standard source. However, with respect to predicting wildfire behavior using the floristic descriptions of vegetation types, the “cause/effect” relationships are actually not well defined. The evolution of the wildfire modelling and behavior prediction has led to the use of fuel models as a primary input, rather than vegetation types, because there are much more well defined physical relationships between the descriptive attributes of the fuel models and wildfire behavior. The following sections will address the process used to “cross-walk” descriptions of the vegetation types typically found (in the Camarillo environment) to industry standard fuel models.
With respect to the specific type of influence, i.e. whether it is static or dynamic, the vegetation types present can exhibit both. Significant changes in vegetation type conditions can change through a longer period of ecological evolution or rapidly (in a manner of days, or even hours) in response to catastrophic environmental events (wildfire, earthquake, wind, flooding, etc.) or intentional management. For the purposes of this assessment this setting element will be treated as a static influence; not taking into account the potential for future changes.
Natural Vegetation Within the FPAA
Within the California Floristic Province, the FPAA is located in the Western Transverse Ranges District of the Southwestern California Region
17. Ecological Provinces and the vegetation resources have been comprehensively mapped through the efforts of the USGS-NPS Vegetation Mapping Program18.
Overlaying the FPAA boundary on the base map generated by this program showed that vegetation alliances characterizing five Regions/Subregions could be found within the boundaries of the FPAA.
These Regions/Subregions, and their dominating alliances and genera are:
• Region 1/Subregion B: Low growing shrub/brush alliances with the dominant genera being Artemisia, Salvia, Baccharis, and Ceanothus;
• Region 3/Subregions A, B, and C: Chaparral, oak woodland, and riparian/semi-riparian woodland alliances with the dominant genera being Ceanothus, Cercocarpus, Artemisia, Salvia, Baccharis, Adenostoma, Arctostaphylos, Toxicodendron, Quercus, Juglans, and Umbellularia, and;
• Region 4/Subregion A: Chaparral, shrub, and oak woodland alliances with the dominant genera being Ceanothus, Artemisia, Salvia, Baccharis, Adenostoma, Cercocarpus, and Quercus.
In addition to these naturally occurring vegetation alliances, consideration must also be given to the various agricultural uses and other surface conditions/land use types that characterize the project area as their differences in wildfire-related influences can be important in regard to the nature and intensity of wildfire that they could generate.
17 Heckard, Lawrence R. 1993.
18 USGS/NPS. May 23, 2007.
Camarillo Wildfire Hazard Assessment
19 Relationship Between Vegetation Types/Land Uses and Fuel Models However, after presenting the natural vegetation type information that is a core element of the study’s setting, an additional, very clear, distinction must be made concerning the information actually driving the modeling activities and assessment of wildfire behavior and impacts. This assessment is actually based on mechanistic influences (as was previously discussed in an introductory section) that affect wildfire’s ability to ignite, cross landscapes, and impact conditions at defined locations. In general, these “behavior predictive” models describe how wildfire moves 1) across the surface of the ground, 2) vertically from the ground into the overstory crown, 3) horizontally through the crown, and 4) creates burning materials (embers) that become airborne and “jumps” ahead of the surface-associated fire advance line. These processes are controlled purely by the laws of physics and, in actuality, the floristic nature of a setting element (generally defined by a distinctive set of individual species present and their relative dominance) does not have a comparably significant influence on wildfire behavior. The setting element that does have this ability to generate significantly different results, with respect to wildfire behavior, is fuel. The specific characteristics of fuels that exert a significance influence include: 1) the amount of flammable material present (either measured in weight or volume), 2) the size classes of material present, and 3) the structural arrangement, both horizontally and vertically, of the fuels (also referred to as fuel bed continuity).
Thus, even though industry-standard wildfire behavior modeling processes continue to use vegetation type nomenclature there is now, for use in this wildfire modeling effort, an additional step that needs to occur. This step involves linking vegetation associations found to be present, primarily by an examination of its structural elements, to a set of industry standard fuel models. This process is commonly referred to as a crosswalk and the “destination” industry-standard fuels models were consistent with the work of H. E Anderson (vegetation types) 19, Scott. Joe H. and E.D Reinhardt (crown
fires)20, and Scott. Joe H. and R.E. Burgan (non-vegetated surfaces)21.
Vegetation-Related Fuel Models Used in the LANDFIRE Modeling Program For conducting the wildfire behavior prediction analysis, the model selected was the Landscape Fire and Resource Management Planning Tools (“LANDFIRE”) model that has been developed as a shared program between the wildland fire management programs of the U.S. Department of Agriculture Forest Service and U.S. Department of the Interior
22. The fuel models used as inputs to the predictive
LANDFIRE modeling program included six that were based on the crosswalk to CalVeg types and four that represented surface conditions that were considered non-burnable as they were either in agricultural uses (field crops, orchard, vineyards) or were truly non-burnable (pavement, urban/suburban development, water surfaces, bare ground). Summarized below are the specific fuel models applicable to the FPAA.
19 H.E Anderson. 1982.
20 Scott. Joe H. and E.D. Reinhardt. September, 2001
21 Scott. Joe H. and R.E. Burgan. June, 2005
22 USDI, IFTDSS. Accessed: April 4, 2023
Camarillo Wildfire Hazard Assessment
20 Fire Behavior Fuel Model 2 (FBMF 2)
Fire spread is primarily through the fine herbaceous fuels, either curing or dead. These are surface fires where the herbaceous material, in addition to litter and dead-down stem-wood from the open shrub or timber overstory, contribute to the fire intensity. Open shrub lands and isolated pine/oak stands, or scrub oak stands may generally fit this model; such stands may include clumps of fuels that generate higher intensities and that may embers. Figure 10 provides an example of vegetation included in the FBFM 2 fuel model. Key specifications for the FBMF 2 fuel model are summarized in Table 5.
Figure 10. Example 0f Shrub/Grass Vegetation Included in the FBFM 2 Fuel Model
Table 5. Specifications for FBMF 2 Fuel Model
Fire Behavior Fuel Model 5 (FBFM 5)
Fire is generally carried in the surface fuels that are produced as of litter cast by the shrubs and the grasses or forbs in the understory. Fires within FBFM 5 are generally not very intense because surface fuel loads are light, the shrubs are young with little dead material, and the foliage provides relatively small amounts of volatile material. Usually, shrubs are short and general occupy high percentages of the surface area. Young, green stands with no dead wood that would qualify as an example of this fuel model would include, laurel, vine maple, alder, chaparral, manzanita, or chamise. Figure 11 provides an example of vegetation consistent with the FBFM 5 fuel model. Key specifications for the FBMF 5 fuel model are summarized in Table 6.
FBFM 2
Attribute Value
Total fuel load, < 3-inch dead and live 4.0 tons/acre
Dead fuel load, 4-inch 2.0 tons/acre
Live fuel load, foliage 0.5 tons/acre
Fuel bed depth 1.0 feet
Camarillo Wildfire Hazard Assessment
21 Figure 11. FBFM 5 Shrub Layer Example Following a Fire
Table 6. Specifications for FBMF 5 Fuel Model
FBFM 5
Attribute Value
Total fuel load, < 3-inch dead and live 3.5 tons/acre
Dead fuel load, 4-inch 1.0 tons/acre
Live fuel load, foliage 2.0 tons/acre
Fuel bed depth 2.0 feet
Fire Behavior Fuel Model 6 (FBFM 6)
Fires carry through the shrub layer where the foliage is more flammable than fuel model 5, but this requires moderate winds, generally greater than 8 MPH at mid-flame height. Fire will drop to the ground at low wind speeds or at openings in the stand. The shrubs are older, not as tall as, and do not contain as much fuel, as shrub types of FBFM 4 (not included in this analysis). Fuel situations to be considered include intermediate stands of chamise, chaparral, and oak scrub (even hardwood slash that has cured can be considered). Table 7 summarizes key specifications for the FBMF 6 fuel model.
Camarillo Wildfire Hazard Assessment
22 Table 7. Specifications for FBFM 6 Fuel Model
FBFM 6
Attribute Value
Total fuel load, < 3-inch dead and live 6.0 tons/acre
Dead fuel load, 4-inch 1.5 tons/acre
Live fuel load, foliage 0.0 tons/acre
Fuel bed depth 2.5 feet
Fire Behavior Fuel Model 8 (FBFM 8)
Slow-burning ground fires with low flame lengths generally characterize this fuel model. However, under certain conditions, if a wildfire were to encounter such a concentration of heavy fuel the result could be a “flare up” where there are higher spread rates and intensities, longer flame lengths, crowning, and production of embers. These certain conditions would include high ambient temperatures, low humidity levels (both atmospheric and fuel moisture percentages), and high velocity winds. In the Camarillo area these conditions are found in the drainage ravines in the mountainous area and in the wooded drainages found on more level terrain. A very important aspect that needs to be properly evaluated is the physical relationship that exists between the fuel types’ locations and those of any adjacent sensitive resources. Table 8 summarizes key specifications for the FBMF 8 fuel model.
Table 8. Specifications for FBFM 8 Fuel Model
FBFM 8
Attribute Value
Total fuel load, < 3-inch dead and live 5.0 tons/acre
Dead fuel load, 4-inch 2.0 tons/acre
Live fuel load, foliage 0.0 tons/acre
Fuel bed depth 0.2 feet
Fire Behavior Fuel Model 9 (FBFM 9)
In the Camarillo FPAA this fuel model is similar in most respects to FBFM 8 and takes the form of oak- dominated woodlands and mixed species stands along drainages. Due primarily to the overall lower fuel loading, fires run through the surface litter slower than FBFM 8 and have shorter flame length. Fall fires in hardwoods are predictable, but high winds will actually cause higher rates of spread than predicted because of spotting caused by rolling and blowing leaves. Concentrations of dead-down woody material will contribute to possible torching out of trees, spotting (via ember production), and crowning. As with FBFM 8 the physical relationship that exists between the fuel types’ locations and those of any adjacent sensitive resources, is of great importance. Figure 12 is an example of surface and ladder fuels conditions typical of FBFM 9. Key specifications for the FBMF 9 fuel model are summarized in Table
9. Camarillo Wildfire Hazard Assessment
23 Figure 12. Surface and Ladder Fuels Conditions Example for the FBFM 9 Fuel Model
Table 9. Specifications for FBFM 9 Fuel Model
Fire Behavior Fuel Model 10 (FBFM 10)
The fires burn in the surface and ground fuels with greater fire intensity than the other timber litter models. Dead-down fuels include greater quantities of 3-inch or larger limb wood resulting from over- maturity or natural events that create a large load of dead material on the forest floor. Crowning out, spotting, and torching of individual trees are more frequent in this fuel situation, leading to potential fire control difficulties. Any forest type may be considered if heavy down material is present; examples are FBFM 9
Attribute Value
Total fuel load, < 3-inch dead and live 3.5 tons/acre
Dead fuel load, 1/4-inch 2.0 tons/acre
Live fuel load, foliage 0.0 tons/acre
Fuel bed depth 0.2 feet
Camarillo Wildfire Hazard Assessment
24 insect- or disease-ridden stands, windthrown stands, overmature situations with deadfall, and aged light thinning or partial-cut slash. Table 10 summarizes key specifications for the FBMF 10 fuel model.
Table 10. Specifications for FBFM 10 Fuel Model
FBFM 10
Attribute Value
Total fuel load, < 3-inch dead and live 12.0 tons/acre
Dead fuel load, 4-inch 3.0 tons/acre
Live fuel load, foliage 2.0 tons/acre
Fuel bed depth 1.0 feet
Land Use Related Fuel Models
Fire Behavior Fuel Model NB 1
The lands within this fuel model category are those covered by dense urban and suburban development.
To be considered as displaying NB 1 characteristics the area must not support wildland fire ignition or spread. In some cases, areas mapped as NB 1 may experience structural fire losses during a wildland fire incident; however, structure ignition in those cases is either house-to-house or by embers, neither of which has been a focus of current wildfire modeling efforts.
Fire Behavior Fuel Model NB 3
Fuel model NB 3 is agricultural land maintained in a non-burnable condition; examples include irrigated annual crops, mowed or tilled orchards, and so forth. However, there are two agricultural uses, orchards and vineyards, that cannot be strictly considered as being non-burnable due to the nature of their vegetation cover attributes. From a purely structural standpoint orchard and vineyard formations can mimic woodland and shrub/brush fire behaviors, respectively.
Fire Behavior Fuel Model NB 8
These are areas of the surface occupied by open bodies of water such as lakes, rivers and oceans.
Fire Behavior Fuel Model NB 9
These are areas of the surface occupied by lands devoid of enough fuel to support wildland fire ignition and spread. Such areas may include gravel pits, arid deserts with little vegetation, sand dunes, rock outcroppings, and beaches.
Distribution of Fuel Models Within the Camarillo FPAA
The LANDFIRE results for fuel model distribution is shown in Figure 13. The comprehensive set of LANDFIRE results are presented on Addendum III to this report. Analysis of the standard fuel models contained within the IFTDSS showed that within the perimeter of the FPAA there were six SFMs that were related to vegetation type present and four that were defined by the physical surface characteristics.
Camarillo Wildfire Hazard Assessment
25 Figure 13. Distribution of Fuel Models Within the Camarillo FPAA
A summary of surface occupation by fuel model is presented in Table 11 where the vegetation-related models are shaded in green and the land use models in yellow.
Table 11. Portions of the Camarillo FPAA Occupied by the Mapped Fuel Models Fuel
Model
Surface
Occupied (ac.)
Surface
Percentage
Fuel Model Type
Contribution
FBFM 2 3,790 10.80%
50.9%
FBFM 5 11,866 33.83%
FBFM 6 12 <0.1%
FBFM 8 1,489 4.24%
FBFM 9 638 1.82%
FBFM 10 33 <0.1%
NB 1 13,124 37.41%
49.1%
NB 3 3,944 11.24%
NB 8 49 0.14%
NB 9 133 0.38%
Total Acres 35,079
Camarillo Wildfire Hazard Assessment
26 The acreage summary presented in Table 11 show several notable results:
• Slightly less than 50% (49.1%) of the FPAA is occupied by surface conditions with low potential for wildfire ignition and movement where;
o 37.41% is in dense urban and suburban development with fire behavior more related to structural conditions, and;
o 11.24% is in agricultural uses, with some of the lands occupied by orchards and vineyards that can exhibit wildfire behavior similar to natural woodland and shrub/brush alliances.
• Fuel models with floristic qualities of natural shrub/brush alliances dominate (44.6% of the total FPAA) the surface coverage;
• A fairly significant percentage (4.24% of the total FPAA) is occupied by a natural vegetation alliance complex dominated by shrub/brush but also containing “jackpot” stands of woodland (usually located along drainages in the elevated terrain surrounding the central basin); • The fuel model with the heaviest fuel loading, FBFM 10, occupies less than 0.1% of the total FPAA.
Environmental Influences
This category of influences that affect wildfire behavior is comprised of two phenomena: Prevailing and extraordinary winds. Both of these environmental phenomena are considered to be dynamic influencers when it comes to determining wildfire behavior and its associated hazard levels. Rather than attempt to handle the very large amounts of micro-temporal wind data that is available in official weather station records, experience has shown that, when assessing wildfire situations, the focus must be elevated to knowledge of the wind behavior patterns over time. For example, Figure 14 shows wind speeds on a monthly basis and how they form an annual pattern23.
Figure 14. Monthly Wind Speed Data for Camarillo, CA
Details regarding these two categories of wind, their prevalence and nature of their influences are discussed in subsections below. It must also be noted that wind, which has significant influence as an individual mechanistic influencer, also acts in concert with other setting conditions that can either exacerbate or minimize its influence. This cumulative effect phenomenon will be discussed in following sections of this report.
23 Weather Spark. April. 4, 2023.
Camarillo Wildfire Hazard Assessment
27 Prevailing Winds
Knowledge of prevailing wind directions and speed is very important when determining 1) the pathways wildfire will take when crossing a landscape, 2) its rate of advance and, 3) the physical mechanisms involved in its advance. Data regarding prevailing winds were recorded at three weather stations that were within a reasonable sphere of impact with respect to exerting influence on wildfire behavior within the FPAA. The three stations were:
• Miller Ranch RAWS [MLXC1: California DCP]
24;
• South Mountain West [SMNC1: California DCP]25, and;
• Thousand Oaks Civic Center [TOCC1: California DCP]26.
The locations of these weather stations, relative to the FPAA, are shown in Figure 15 and pertinent information for each station presented in Table 12. The information shown in the table has been separated into three categories, 1) location data and annual summaries of wind information (non-shaded cells), 2) a six-month summary of wind information for a period identified as the “non-fire season” (October to March and green-shaded cells), and 3) a second six-month summary for the period identified as the “fire season” (April to September and orange-shaded cells). The prevailing wind directions are presented graphically in Figure 1627 and shows the percentage of hours in which the mean wind direction is from each of the four cardinal directions. Excluded are hours spent in null conditions (wind speeds less than 1.0 miles per hour. The more lightly tinted areas at the boundaries of each cardinal direction show the percentage of time spent in the intermediary directions (northeast, southeast, southwest, and northwest).
24 ISU-Mesonet, 10 September, 2022.
25 Ibid
26 Ibid, 11 September 2022a
27 Weather Spark. April 4, 2023
Camarillo Wildfire Hazard Assessment
28 Figure 15. Locations of Weather Stations Providing Data for Use in the Assessment
Table 12. Wind-Related Information Provided by Local Three Weather Stations Attributes Meteorological Station
SMNC1 MLXC1 TOCC1
Metadata
Network CA-DPT CA-DPT CA-DPT
Distance (mi.) 5.7 5.0 10.9
Bearing to Station 138° 350° 287°
Collection Period 7/10 – 10/22 1/20 – 9/22 10/19 – 9/22 Wind Data
– Annual
Summary
Bearing L1 WDB: 150°-230° WDB: 260°-310° WDB: 90°- 140° Bearing L2 WDB: 30°-50° WDB: 60°-80° WDB: 230° - 290°
Speed-(mph) 3.7 6.8 3.0
Calm Conditions 20.2% 20.3% 27.5%
Wind Data
– Non-Fire
Season
Bearing L1 WDB: 170°-240° WDB: 60°-80° WDB: 100°-140°
Bearing L2 WDB: 20°-100° WDB: 250°-310° WDB: 240°-290°
Wind Speed 3.8 6.8 3.4
Calm Conditions 19.9% 16.8% 21.9%
Wind Data
–
Fire
Season
Bearing L1 WDB: 160°-230° WDB: 250°-30° WDB: 90°-130°
Bearing L2 n/a n/a WDB: 230°- 300°
Wind Speed 3.7 5.4 2.6
Calm Conditions 19.9% 23.7% 34.8%
Camarillo Wildfire Hazard Assessment
29 Figure 16. Graphical Presentation of Prevailing Wind Directions for Camarillo, CA.28
In Figures 17 and 18 the wind information recorded at each station is indicated by colored arrows, bright blue for the NFS and red for the FS. The data recorded at all of the stations typically showed two “wind direction bundles” (WDB) of wind bearings; one bundle showing clearly dominating characteristics (indicated by the solid-lined blue arrows in Figure 17 solid red lines n Figure 18) and a second with less domination (indicated by the hashed cyan arrows in Figure 17 and the hashed yellow arrows in Figure 18).
28 Weatherspark. April 4, 2023
Camarillo Wildfire Hazard Assessment
30 Figure 17. Non-Fire Season Wind Directions Associated with the Three Weather Stations
Figure 18. Fire Season Wind Directions Associated with the Three Weather Stations
Camarillo Wildfire Hazard Assessment
31 Extraordinary Winds
Analyzing the prevailing wind parameters recorded at the three weather stations did not reveal a significant potential for a wildfire to be pushed toward Camarillo from a high risk position. This observation is further supported by the pattern of historic wildfire shown in Figures 6 and 7. It is clear that wildfires have been historically present, and numerous, in the immediate area of the FPAA but no significant incursions have been made into Camarillo.
However, unique to southern California are extraordinary winds, known as Santa Ana winds, that blow from interior locations to the east toward the Pacific Coast to the west in response to extraordinary pressure and temperature differentials. Figure 19 shows a potential pattern of fire-front advance under the sustained east-to-west winds typical of Santa Ana conditions. There are avenues characterized by ground conditions associated with more dangerous wildfire behaviors (i.e. multi-layered vegetation structures with high fuel loads and high fuel-bed continuities, and more steeply sloped terrain) that align with the east-to-west axes of the Santa Ana winds. Furthermore, referring to Figure 18, it can be seen that there is some directional alignment with prevailing winds recorded at the Miller Ranch (MLXC1) and Thousand Oaks Civic Center (TOCC1) weather stations in the NFS; the period in which Santa Ana conditions are most likely to occur. These winds tend to be relatively hot and dry and can have greater than normal wind speeds
29. The multi-influence effects resulting from this combination of prevailing winds, Santa Ana winds, more extreme terrain conditions and the fuels characteristics could exacerbate wildfire behavior in the fall season.
Figure 19. Possible Movement Patterns of Winds Under Santa Ana Conditions
29 Fovell, Robert. 2014.
Camarillo Wildfire Hazard Assessment
32 SPECIAL RESOURCE SITUATIONS
This assessment was designed to support updates to Elements in the Camarillo General Plan30 (“GPE”) as they relate to current wildfire hazard levels. To provide a sufficiently broad base of information supporting the GPE update decision process several special resource situations (features and conditions) were also addressed along with providing the regional WHL results. This project was scoped to allow identification of the features and conditions, locate them within the wildfire behavior-related setting, and to some degree, describe how they could be affected should they be involved in an uncontrolled wildfire event. This assessment was not scoped to do an in-depth study of the nature and intensity of these potential effects nor develop detailed protective mitigation management plans.
Roads with Elevated Loss of Function Vulnerability
Road conditions and functioning are one critical component to any disaster preparedness/response plan.
For a defined set of named roads in the FPAA this assessment completed an analysis that integrates considerations of both hazard and risk levels, 1) an assessment of the level of hazard that the subject roads would be involved in a wildfire event as a result of the wildfire-related setting characteristics, and 2) risk that a subject road, or road segment, would lose its ability to function if involved in a wildfire event. In this context loss of function (“LOF”) means that the subject road, or individual segment thereof, loses its ability provide, 1) access for emergency wildfire response actions, and/or, 2) use for the purposes of evacuation.
The identification of the roads addressed in this assessment was guided by the hierarchal framework set out in Caltrans’ Functional Classification System (“FCS”) 31 with the specific roads shown on six FCS
maps covering the FPAA32. Twenty-six roads, in three Caltrans’ classifications, were identified within the FPAA. A general view of the roads addressed, color-coded by FCS classification, is presented in Figure 20.
The assessment addressed a total of 26 named roads that involved 55 distinctly different segments. For each distinctly identifiable segment the following actions occurred: 1) One of the three possible WHL levels was assigned based on an evaluation of the wildfire risk posed by adjacent fuel model(s), 2) the length of each uniquely identifiable segment was determined using the “Add Path” function available as part of the Google Earth Pro platform, and 3) a .kmz file was stored for the segment.
The assignment of WHL level was determined when the following vegetation, or land-use, types bordered one, or both, sides of a subject road segment:
Low – High density urban or suburban development, commercial or industrial enterprises, native grasslands, water surfaces, bare ground, or cereal or row-crop agricultural enterprises;
30 City of Camarillo. 2004.
31 Caltrans, 2022.
32 Caltrans CRS Grid Maps (6), 2022.
Camarillo Wildfire Hazard Assessment
33 Medium – Low density suburban developments with high percentages of natural, or landscaping-related, vegetation, natural low-stature shrub/brush types, or orchard/vineyard enterprises;
High – Native higher-stature shrub/brush type, savanna types, dense hardwood woodlands, or forests.
Below, in Figure 21 are the roads and color-coded risk levels for the 55 different segments. Segments coded with light green showed the lowest vulnerability; the orange indicates a moderate level; and red the highest vulnerability.
Figure 20. Named Roads Addressed in the Wildfire Hazard/Risk Assessment
Camarillo Wildfire Hazard Assessment
34 Figure 21. Road Segments Addressed in the Vulnerability Assessment
Table 13 presents the findings of the risk interpretation broken down into comparative distances (in feet and miles) for each risk level represent by named road. A presentation of the complete results, broken down by individual road addressed in this study is contain in Addendum III to this report.
Interpreting the summary results presented in Table 13 shows a very clear dominance (89.1%) by road segments in the “Low” WHL level class in both the CPSA and EPA portions of the FPAA. Where segments occurred that were designated as having a “Medium” WHL level it was in the presence of orchard/vineyards on one, or both sides of the road and low stature natural grassland or shrub/brush lands, and wooded drainages. The “High” occurrences were all along the Ventura freeway where it passes through hilly terrain with moderate-to-high slope percentages (20%- 50%) and occupied by moderate-to-high stature shrub/brush lands and pockets of mixed woodlands.
Table 13. Results of the Road Vulnerability Assessment
Attributes
CPSA EPA Totals
Low Medium High Low Medium High
Total Feet 264,267 14,756 6,609 72,251 18,192 1,555 377,630 Total Miles 50.05 2.79 1.25 13.68 3.45 0.29 71.52
Percentages 69.98% 3.91% 1.75% 19.13% 4.82% 0.41%
Camarillo Wildfire Hazard Assessment
35 Communities Vulnerable to Elevated Levels of Impacts from Wildfire Some communities, due to their location and nature of their makeup, can be more vulnerable to adverse impacts should they be involved in a wildfire incident. Knowledge of their existence and characteristics is an important part of proper planning addressing 1) wildfire issues (pre-incident preparation, emergency response, and subsequent rehabilitation), and 2) access issues (both access for emergency response and evacuation). Principal characteristics that distinguish these more vulnerable communities from others are:
• Direct, or at least, reasonable contact with wildland conditions – In this analysis wildland conditions are defined as being only those directly related by way of their influence on wildfire behavior. More precisely, the focus is on those conditions that could reasonably result in generating dangerous wildfire behaviors;
• Possessing a single point of road access – As a wildfire event is evolving the most critical operational elements are 1) getting to the location in order to gain control over the wildfire, and 2) moving any involved citizens out of harms ways via evacuation, and; • What is the nature of the wildfire behavior-related conditions that are within, or directly adjacent to, the community boundaries. It is important to understand what type of wildfire fuels are present, how they are distributed within the community boundaries, how critical infrastructure could be adversely impacted, are there any “shelter-in-place” opportunities available.
Using the three Interpretation Criteria (“IC”) criteria described above, a study was completed for the FPAA in order to identify and map the subject communities. The initial step involved conducting a thorough interpretation of the Google Earth Satellite Imagery (GESI) for the FPAA. The objective was to identify isolated suburban or rural-residential developments that meet the three ICs. Where the criteria-based decision process identified a suitable candidate community its boundary was defined and put into proper geographic position on the GESI. This process identified seven separate locations that met the criteria requirements. The results of this analysis are presented in Figure 22.
Figure 22 shows, over current GESI images, the geographic distribution of the locations that met the selection criteria. This figure shows the set of six magenta-shaded polygons representing the extent of each identified community, and another area warranting consideration (thick cyan boundary line) in relation to 1) the CPAA (thin yellow-lined boundary) and 2) the boundary of the FPAA (medium-thick cyan line). Figure 23 is an enlargement of one of the areas selected, showing the extent of the polygon (medium-weight magenta line), the roads system serving the community, the patterning distribution of the structures, and the matrix of the natural, and landscaping-related, vegetation types, characterizing the feature.
Camarillo Wildfire Hazard Assessment
36 Figure 22. Seven Locations Identified as Communities With Elevated Vulnerability
Figure 23. Enlargement of One Community With an Elevated Vulnerability to Wildfire
Camarillo Wildfire Hazard Assessment
37 Table 14 presents, for the six identified communities, each location’s metadata: Development name, surface area occupied, and the geographic coordinates of the surface road access point. The deliverables resulting from this task area will include:
• Map, delivered as the hard-copy (Figure 22), and;
• Digital files of the polygons representing each community, in agreed-to formats, to support their GIS use in subsequent studies.
Table 14. Key Data for Communities at Elevated Risk
High Tension Electrical Lines
High tension electrical line (“HTEL”) systems are considered a sensitive feature because they can be both very vulnerable to loss of function should they be involved in a wildfire event but also a potential source of wildfire ignition. Figure 24 shows the location, which is contained entirely within the EPAA portion of the FPAA, of an Electric Transmission Line (red line) and a Electric Distribution Line (orange) system.
Development Surface
Area (ac.)
Access Point
Latitude(˚) Longitude
(˚)
Alosta Dr. 53.4 34.243356° -119.028134°
Grandview Dr. 56.2 34.247529° -119.039872°
Oceanview Dr. 26.7 34.247776° -119.031080°
Ridge View St./Adhor Ln. (2 access
points)
161.0 34.206035°
34.205849°
-119.998983°
-119.982893°
San Clemente Way 25.5 34.246847° -119.044761°
Santa Cruz Way/W. Highlands Dr. (2
access points)
98.8 34.245310°
34.246135°
-119.049139°
-119.047321°
Total 422.5
Suburban/wooded, NW portion of FPAA 723.0
Camarillo Wildfire Hazard Assessment
38 Figure 24. Location of High Tension Electrical Line System Within the FPAA
An enlargement of a section of the HTEL shows a very typical crossing of “ridge-to-drainage bottom” terrain. In this biological region made up of flat areas, mid-slope locations, and ridgetops, the landscape is typically occupied by low-growing herbaceous and shrub/scrub associations; mid-height-to-tall woodland formations are typically located in the drainages. In regard to possible LOF, in the event of a wildfire, the critical aspect is how high above the surface the lines been placed. Low-hanging lines can be damaged if they pass over fuel models that generate comparatively longer flame lengths, higher thermal intensities, and longer residence times, whereas higher placed lines minimize these risks.
Without direct field observation it was not possible to evaluate the actual ground-to-line separation distance (also referred to as deflection) but the process of interpreting the GESI indicated that, generally, deflections are adequate to provide minimal levels of LOF risk. Given the background environmental setting elements (ambient temperatures, relative humidity, wind direction and speed, fuel model characteristics) HTEL-sourced fire ignitions are generally associated with equipment failure and prediction of their occurrence is beyond the scope of this study. Should vegetation present at the ignition location combust then the fire’s potential for subsequent movement would be influenced by the setting elements addressed herein. Figure 25 is an enlarged aerial view of an HTEL within the FPAA.
Camarillo Wildfire Hazard Assessment
39 Figure 25. Enlarged View of a Portion of the High Tension Electrical Line
Vegetated Drainages
Drainage features have the potential to be a setting element with significant influence on wildfire behavior. A key condition is that the microclimates in these locations are typically cooler and have comparatively higher soil moisture availability, both in terms of amount and duration. These microclimatic conditions enable the occupation of the site by vegetation that is dense, continuous, integrated vertically, and dominated by tree and shrub species. The “cross-walked” fuel models are shrub and woodland types and are characterized by, 1) continuous fire-front advance, 2) moderate advance rates, 3) longer flame lengths, 4) longer duration at one location, 5) higher thermodynamic intensities, and 6) the potential for generating significant amounts of airborne embers. In addition to the mechanistic fuel-related issues described above, these vegetated drainage features have other characteristics, especially when sited in urban settings, that warrant consideration when generating policy guidance and practices:
• Due to the potential availability of water, cover, and fairly stable temperature regimes these sites can be attractive to the “house-less” segment of the population; typically bringing with them the use of open-pit fires for warming and food preparation. This use is an acknowledged source of wildfire ignitions;
• The lands within these features are typically under the ownership of a government agency or special district whose set of management practices are not influenced by wildfire issues, and;
Camarillo Wildfire Hazard Assessment
40 • Should a wildfire event occur in these features contained within the urban setting the responding units may not be equipped, trained for, or experienced in, wildland fire; potentially requiring an expansion of the call-out to other units.
The previously described GESI interpretation process was applied and a total of 643 acres of surface within the FPAA was occupied by this feature. For the FPAA as a whole, 160 acres (25%) were located within the CPAA and the remainder, 482 acres (75%) occurred within the EPAA. With such a significant split between lands occupied by this feature within the Camarillo city limits and those in the surrounding un-incorporated area, collaboration would be a key activity in developing policy and practice regarding this wildfire issue. Below, in Figure 26, is presented the distribution of these vegetated drainage features throughout the FPAA and their relation to the two project study areas; within the CPAA and in the EPAA.
Figure 26. Distribution of Vegetated Drainages Within the FPAA
Figure 27 shows an enlarged view of an example of a vegetated drainage feature. Notable is the linear form and how the feature abuts several different land use classifications. Should wildfire occur in the feature, and be in combination with a trailing wind the feature can act as a functional pathway for both direct fire front advance and “far-forward” ignition by airborne embers.
Camarillo Wildfire Hazard Assessment
41 Figure 27. Enlarged View of a Vegetated Drainage
WILDFIRE HAZARD LEVEL DESIGNATIONS
This assessment of, and subsequent conclusions drawn regarding, regional wildfire associated hazard levels was completed in two parts:
• Considering how the individual environment setting elements contributed to WHL, and then, • How the mechanistic influences of the individual setting elements could potentially acted in concert with those of other individual influences (i.e. cumulative effects).
Through a number of discussions at project team meetings the number of comparable WHL levels that were to be mapped within the FPAA was set at three: “Low”, “Moderate”, and “High”. The discussions also acknowledged that a finer breakdown in WHL levels, and more site-specific determinations, would require subsequent analyses that were not within the scope of work for this Study; most likely requiring these subsequent analyses employing a multi-stage approach.
Assessment of Individual Setting Components
As previously stated, the first step in linking the ground conditions to one of the three levels of wildfire hazard, was to establish the relative intensity of effect each individual category had on wildfire behavior.
Camarillo Wildfire Hazard Assessment
42 For example, the terrain slope class was broken down into three subclasses based on approximate steepness: 0% - 11%, 12% - 45%, and >45%. Where slopes for a defined area were less than 11% it was assigned an influence factor (“IF”) equal to 1 (a comparatively low level of influence), whereas, locations where slopes exceeded 45% were assigned an IF of 3 (indicating an influence three time greater than the lowest slope subclass). How each of the general classes for each setting element were broken down into reasonable subclasses, and their associated IFs, were used in the prediction model is explained in the following sections.
Terrain Slope
As a result of applying a professional judgement process to assigning WHL levels on the basis of terrain slope it was concluded that the three subclasses of slope, shown in Table 3, formed a reasonable set of decision criteria. The primary considerations in making these assignments included 1) the nature and intensity of the fire behavior that could result if a fire event occurred on lands in each category, 2) the resistance to gaining control over the wildfire, and 3) mitigation management implementation constraints. For each slope subclass the discussions below describes 1) the general location of the subclass’s occurrence within the FPAA, and 2) more detail supporting the assignment:
• Low – This class occurs primarily in the central basin of the FPAA, and is almost completely occupied by degrees of urban development;
• Moderate – Lands in this category are located where slopes classes begin to constrain urban, high-density suburban, and agricultural land uses. Also found on lands in this category is a high proportion of the “communities vulnerable to elevated levels of impacts from wildfire”, and;
• High – This class is entirely associated with the mid-slope and ridgelines of the elevated terrain ringing the central basin. The terrain associated with this slope class is highly dissected forming a complex matrix of occurrences representing the full value range of slopes (45%-90%).
After identifying the subclasses’ influencing factors (IF), a single WHL level assignment for the terrain slope class was developed by using a system of three linear equations; where there are two input variables and the result is a comparable ranking figure. The first input variable is the subclasses’ IF, and the second is the acreage percentage of the subclasses’ FPAA surface occupation. Using the simplest weighting factors of, Low = 1, Moderate = 2, and High = 3. The three equations would be:
Low (< 11%): 1 x 62.1 = 62.1 Contribution to Total = 41.7% Moderate (12%-45% : 2 x 27.0 = 54.0 Contribution to Total = 36.3% High (>45%): 3 x 10.9 = 32.7 Contribution to Total = 22.0%
Total Score for Slope Class = 148.8
The individual equations produced ranked contributions, and then when summed, a total value unique to the relationship of slope’s influence on WHL. It is the pattern of the contribution percentage of each slope subclass that provides the indication of the influence of slope over the entire FPAA. Only 22% of the total area is occupied by slope conditions that carried an IF of 3 and would be considered to have the most adverse effect on fire behavior. Furthermore, a majority of these lands are in the EPAA (i.e. not having an effect on resources within the City’s limits). The clear predominance of lands ranging from
Camarillo Wildfire Hazard Assessment
43 flat to moderately-sloped indicates a regional rating of Low-to-Moderate for the entire FPAA. Thus, it was concluded that, when considering the influence of terrain slope alone, this setting element would have a comparatively minor effect on WHL level for the Camarillo FPAA.
Aspect
For the purposes of assigning a FPAA-wide WHL level, aspect, as shown in the LANDFIRE model results, would be analyzed in a manner similar to terrain slope. However, in this case the subclass IF would be assigned based on 1) the microclimate characterizing each aspect subclass and 2) the characteristics of the vegetation formations occupying each aspect subclass that relate to fuels conditions. Table 15 shows the assigned factor for each aspect category and color coding for group aspects that have a similar influence on WHL level (Cyan represents the aspect most closely related to the “Low” WHL level; yellow indicating the group of aspect most closely related to the “Medium” WHL level, and orange the “High” level.
Table 15. Categories of Aspect Derived From the Digital Database Category
Descriptions Occupation of FPA Surface Area (ac. & %)
General IF Acres Percentage Group Percentage
Flat 1 17,618 50.2% 50.2%
NW 2 2,493 7.1%
22.6% N 2 2,612 7.5%
NE 2 1,579 4.5%
E 2 1,228 3.5%
SE 3 2,026 5.8%
27.3% S 3 3,226 9.2%
SW 3 2,197 6.3%
W 3 2,100 6.0%
Total Acreage 35,079
Once again there are three WHL IFs and an associated magnitude factor: 1, 2, and 3. For each magnitude factor brief descriptions of the differentiating characteristics of each group are:
• Magnitude Factor 1: “Flat” areas lacking directional orientation. Insolation is unaltered by topographic variations, temperatures follow ambient fluctuations, and predominant land uses, include urban and high-density suburban development and agricultural endeavors.
• Magnitude Factor 2: Northwest, North, Northeast, and East oriented categories. These aspects are characterized climatologically by low sun-angles and elevated degrees of shading, cooler temperatures, and elevated levels of humidity. Typical vegetation associations are more mesic in nature including relatively robust woodlands and scrub/brush associations.
Camarillo Wildfire Hazard Assessment
44 • Magnitude Factor 3: West, Southwest, South, and Southeast oriented categories. These aspects are characterized climatologically by higher sun-angles and very little shading, warmer temperatures, and lower levels of humidity. Typical vegetation associations are more xeric in nature including open woodlands, scrub formations, chaparral formation, and grass/forb formations.
Once again, deriving a FPAA-wide determination of the WHL level sourced from the aspect class involved three equations with the same input variables (IF and surface occupation percentage). These equations were as follows:
Low (IF 1): 1 x 50.0 = 50.0 Contribution to Total = 28.2% Moderate (IF 2) 2: 2 x 22.6 = 45.2 Contribution to Total = 25.5% High (IF 3) 3: 3 x 27.3 = 81.9 Contribution to Total = 46.3%
Total Score = 177.1
The individual equations produced ranked contributions, and then when summed, a total value unique to the relationship of the aspect classes’ influence on WHL. Even with a clear dominance of the surface area within the FPAA of lands without distinct aspect influences (basically flat or very gently sloped) the factored analysis produced a relatively unremarkable contribution (28.2%) to the overall score. The analysis for the more mesic aspect classes showed a similar result; a 25.5% contribution. The more arid grouping did show a significant difference with a 46.2% contribution. Further consideration of this result came to two general conclusions, 1) the increase in contribution was due primarily to the assignment of a Magnitude Factor of 3; not a dominance of lands occupied, and 2) the influence of aspect would be better rolled into the analysis of the influence exerted by the fuel models present on these lands.
It was concluded that the aspect setting element would play a very minor role in determining WHL level and further consideration in this analysis would not be warranted.
Presence of Standard Fuel Models
Professional experience supports the conclusion that the fuel models present have the most significant influence on WHL levels. Examination of the Calveg types, and non-vegetation surface characteristics, contained within the digital database for the FPAA showed that they “cross-walked” to nine distinctly different fuel models (as previously presented in Table 11).
Below are discussions, broken down into general influence Magnitude Factors (1 through 4), that describe the SFMs characterizing the Factor in terms of, 1) the surface area occupied within the FPAA, 2) the occupation percentage, and 3) descriptions of the surface conditions.
Magnitude Factor 1: Basically, surfaces that will not support the advancement of fire occupying 8,894 acres (11.4%) of the FPAA. The acreage figure for the agriculture category (AGR:NB3) does not consider that there is a difference, with respect to fire behavior, between the arborescent types (orchards, vineyards, woody shrubs) and row, cereal, and feedstock types. This category, assigned the lowest magnitude factor, Includes Scott/Burgan fuel models, NB1, NB3, NB8, and NB9.
Camarillo Wildfire Hazard Assessment
45 Magnitude Factor 2: A mix of vegetation formations comprised of grass/forb swards and sparse brush within grass/forb swards that occupies 6,915 acres (8.7%) of the FPAA. This category is comprised of a sole fuel model, Anderson’s fuel:
• FBM2 – Fire Behavior Fuel Model 2: Fire spread is through the fine herbaceous fuels and are typically surface fires only with low intensities and flame lengths. • FBM5 - Fire Behavior Fuel Model 5: Fire spread is through a complex of fine herbaceous fuels and low growing herbaceous and shrub species. The fires are typically surface fires only with low intensities and low-to-moderate flame lengths.
Magnitude Factor 3: A spectrum of hardwood and brush/scrub formations comprised of three principal types: Open hardwood formations with grass/forb, medium density mixed hardwood formations, and scrub/brush lands occupying 21,201 acres (26.8%) of the FPAA. This category includes the following Anderson fuel models:
• FBFM4 – Fire Behavior Fuel Model 4: Fires are intense with fast spread involving the foliage and live and dead fine woody material in the crowns. Fuel bed is primarily stands of mature California mixed Chaparral.
• FBFM6 – Fire Behavior Fuel Model 6: Fire is generally carried in the surface fuels of shrubs.
Fire has generally low-to moderate intensities and with low-to-moderate flame lengths due to the moderate stature of the vegetation involved.
Magnitude Factor 4: Taller, dense, and multi-layered formations dominated by conifer species and a hardwood/conifer mix occupying 42,095 (53.2%) of the FPAA This category includes the following Anderson fuel models:
• FBFM9 – Fire Behavior fuel Model 9: Fire runs through the surface litter faster than model 8.
Formation is characterized by a mix of conifer and hardwood species and stands that are multi- storied in structure. This fuel model will carry both surface and full structure involvement and can be a significant source of embers.
• FBFM10 – Fire Behavior Fuel Model 10: Fire burns with greater intensity as dead and downed fuels are in higher proportions than other types. Formation is characterized by a mix of conifer and hardwood species and stands that are multi-storied in structure. This fuel model will carry both surface and full structure involvement and can be a significant source of embers It was determined, that for deriving a FPAA-wide determination of WHL level, four separate equations were warranted, that they used the same input variables (magnitude factor and surface occupation percentage), and also the same percentage value contribution to the accumulating total for the FPAA.
These equations were as follows:
Magnitude Factor 1: 1 x 11.4 = 11.4 Contribution to Total = 3.54% Magnitude Factor 2: 2 x 8.7 = 17.4 Contribution to Total = 5.40%
Camarillo Wildfire Hazard Assessment
46 Magnitude Factor 3: 3 x 26.8 = 80.4 Contribution to Total = 24.97% Magnitude Factor 4: 4 x 53.2 = 212.8 Contribution to Total = 66.09%
When considering assigning an overall WHL level to the Camarillo FPAA it was clearly evident that a significant majority of the surface area (80.0%) was occupied by fuel models that could reasonably generate moderately high-to-dangerous wildfire behavior if involved in an incident. This preponderance of influence dictated the finding that, for the FPAA, overall WHL level would be in the “High” category due to the fuel models present.
Prevailing Winds
When considering whether there are prevailing winds that could cross through the FPAA the only record of a reasonable potential was contained in the data recorded at the South Mountain (SMNC1) weather station, the location of which can be seen in Figure 15. These winds occurred during the fire season (April through September) and exhibited moderate velocities (averaging 3.7 MPH).
Not only would the presence of well-defined prevailing winds be considered, at most, to be at a low level of likelihood but the attributes show similar impact potential. The highest average annual wind speed was 6.8 MPH at the Miller Ranch station. This is in a Beaufort 33 Classification 2 and considered
to be a “light breeze”34. Lastly, from data recorded at all three weather stations the average annual percentage of “calm” conditions was 22.7%.
It was reasonably concluded that the mere presence of prevailing winds did not contribute significantly to a rise in WHL level. However, the cumulative effects, i.e. when those wind currents did interact with various features and/or conditions situated in the landscape, could reasonably be a principal contributor to elevated WHL levels.
Extraordinary Winds
For the purposes of this discussion two specific types of extraordinary winds were considered:
• “Fire-Storm” types that typically occur when unusually high concentrations of fuels are encountered by a wildfire with its advance being augmented by more extreme slopes or trailing winds. Similar to diurnal winds the level of predictability of occurrence of this type of event is, 1) not reflected in weather station data, and 2) its evolution depends on a combination of very localized conditions that are not present in the Camarillo project area, and;
• Santa Ana winds.
Fire-Storm Generated Winds
The results of this setting analysis indicate that the conditions for a fire-storm occurrence do not exist within the FPAA. The primary constraint is a lack of larger areas where there is accumulations of heavy fuels in muti-level formations (jackpot fuels) that can produce the very high intensity fire that pulls
33 Royal Meteorological Society. April 18, 2023.
34 NOAA/NWS. January 2023.
Camarillo Wildfire Hazard Assessment
47 toward a central location (i.e. generating its own wind pattern). A second constraint involves the terrain slope element. On all edges of the central basin the only direction of wildfire travel that would be augmented by terrain slope would be away from the resources in the CPAA. Lastly, the likelihood of prevailing wind assistance increasing fire-front advance rates (basically combining with slope tendencies) is not supported by the weather station data.
Santa Ana Winds
During the typical Santa Ana wind period (September to May 35) the FPAA can be impacted by the
easterly winds that exit the Mojave desert region via the pass at Escondido Summit and funnel down Soledad Canyon into the Newhall area. Continued westward movement follows topographic configurations including the Santa Clara River, Simi, and Thousand Oaks valleys. Examination of the weather station data for the NFS (the season in which Santa Ana conditions typically occur) show primary bearings that compare with the pathways followed by the Santa Ana winds.
When evaluating the risk to resources in the CPSA posed by the occurrence of Santa Ana winds several conditions were considered:
• The “ring” of elevated terrain could actually shelter the CPSA by deflecting and/or diffusing the force of the winds;
• Should the winds crest the ridges comprising the elevated terrain “ring” they would ultimately be blowing downhill; directions that would be adverse to the upslope augmentation of fire-front movement, and;
• The intensity of a cresting wind-driven wildfire could generate a significant number of burning embers that could be pushed toward the CPSA. Given that 1) studies have shown that live embers can travel up to 20 miles
36, 2) that the measures of distance between the ridge crest and the resources in the CPSA range from 0.45 to 2.51 miles, and 3) the ember generation would come from the finer fuels comprising the herbaceous, scrub/brush, and open woodlands that characterize the covering vegetation in these locations, it is reasonable to conclude that the numbers of “live” embers reaching the CPSA would pose a significant threat to resources in the CPSA.
The overall conclusion is that the Santa Ana type of extraordinary winds alone can exert a significant influence on WHL within a regional context and further consideration in this analysis is warranted.
Multiple Setting Components – Cumulative Effects
In wildfire situations the influence of individual setting components (prevailing winds, terrain slope, and aspect) often do not result in observably significant changes in WHL levels; an exception being, as described in the previous section, the presence of fuel models. Detectible changes in WHL level are
35 Fovell, Robert. May, 2014.
36 The Brush Fire Foundation. April 14, 2023.
Camarillo Wildfire Hazard Assessment
48 usually definable only when two, or more, components act in combination; a process often referred to as “cumulative effects” (“CE”). An example of this combining process would involve a prevailing wind of notable velocity blowing directly up a 40% south-facing slope through dense woodlands or forests.
Specifically identifying what combinations of setting components result in undesirable WHL conditions and the locations where they are within an area for which wildfire planning is needed is of primary importance.
Unfortunately, identifying the locations of the full range of possible setting component combinations for an area as large as the Camarillo FPAA requires a significant level of effort and was out of the scope of the current project. Not only would the analysis have to address the presence and conditions of the various setting components but it would most likely also include consideration of specific features, or resources, that would be vulnerable to adverse impacts from wildfire. These types of multi-variant and geographically descriptive analyses are typically accomplished using standard geographic information systems analysis procedures and would be recommended as logical follow-on projects using the information generated by the current effort.
Distribution of Wildfire Hazard Levels within the FPAA
Employing a convergence of evidence approach, a TSS team member37, experienced in both wildfire behavior analysis and satellite image interpretation, identified, and mapped on the GESI, surface areas whose setting elements indicated the appropriate WHL level classification. The TSS analyst considered 1) the effects of having the individual setting elements addressed in the analysis present terrain conditions (slope and aspect), fuel model, and wind influences, 2) if present, how significant would each individual setting element’s influence be, and 3) if multiple setting elements were present would they interact, through a process of cumulative effects, to produce a more significant influence than any of them individually.
After an appropriate process of considering the results of the mechanistic process defining WHL, the TSS analyst then needed to produce distinct mapping units (or polygons) that aligned with the constraints put on the process by the minimum mapping area specifications. Adherence to the minimum mapping area requirements resulted in mapping units with higher internal attribute heterogeneity which is a typical characteristics of mapping project areas that are regional in scope. These heterogeneous-by- necessity maps units will be discussed, along with solution opportunities in the concluding section of this report.
The evaluation proceeded in the following manner. Applying a very basic assumption that the vegetation type/land use-based fuel model present exerts the greatest influence on wildfire behavior, the TSS analyst first determined what were the SFMs present in the subject area. This process was based on TSS’ analyst’s experience in satellite imagery and incorporation of the information contained in the CalVeg database and the LANDFIRE products. The next step was to determine, for the area initially defined by the presence of the VTR fuel model, the slope percentage, and aspect, categories represented. Again, this second step involved TSS’ capability and reference to the slope and aspect databases used as inputs in
Camarillo Wildfire Hazard Assessment
49 the LANDFIRE fire behavior modelling. Lastly, the wind influence potential (for all three types) was identified. Once the influencing factors were identified for a subject area then the most likely cumulative effects scenario was considered, the subject area was mapped on the GESI, and one of the three possible WHLs was assigned. A map of the distribution of the three WHLs within the FPAA is shown in Figure 28, with a summary of the WHL levels involved in Table 16.
Figure 28. Distribution of Wildfire Hazard Levels Within the FPAA
Camarillo Wildfire Hazard Assessment
50 Table 16. Wildfire Hazard Risk Levels Acreage Data
WHL Surface Areas of WHL Levels Map Shade Acres Proportion Low (1) 21,187 60.4% Yellow
Medium (2) 4,045 11.5% Orange
High (3) 9,847 28.1% Red
Total Acres 35,079
The ground conditions included in each of the three final mapped categories are:
WHL – Low
• Surface occupied almost exclusively by dense urban commercial enterprises, urban and suburban residential developments, and field and row-crop agricultural enterprises; • Located in a broad basin;
• Slope less than 10%;
• No aspect differentiation
• Sheltered to a degree from Santa Ana winds by ring of elevated terrain, and; • Very low percentages of surface occupation by vegetation other than agricultural enterprises.
WHL – Medium
• Surface occupation a mix of wildland conditions and uses and significant areas of orchard and vineyard enterprises;
• Located on lower mid-slope topographic positions;
• Slopes in the 10% - 30% range;
• Less pronounced aspect differentiation;
• Less potential for involvement in Santa Ana wind-driven wildfire events, and; • Mixed occupation of the surface by natural vegetation associations, arborescent agricultural enterprises, and suburban developments with a relatively high occupation by native and landscaped vegetation.
WHL – High
• Surface occupation completed dominated by wildland conditions and land uses; • Elevated, highly dissected terrain;
• Slopes in the 30% - 50% range;
• Significant proportions of southerly oriented terrain; • Potentially involved in Santa Ana wind-driven wildfire events, and; • Occupied by shrub and brush alliances and fragment hardwood woodlands.
Interpretation of Results and Recommendations
These closing sections will address:
• The factual information generated regarding the nature, and distribution, of WHLs within the FPAA;
Camarillo Wildfire Hazard Assessment
51 • The various components of the assessment process, itself, that led to the results; • Implications of Special Resources situations, and;
• Recommendations.
Individual Setting Elements’ Influence on Wildfire Hazard Risk Levels This assessment evaluated a select number of setting elements that could have a direct, observable, and mechanistically understandable, effect on wildfire behavior and its various hazard levels. This evaluation indicated that there were three classes of setting elements that met these basic criteria:
• Terrain conditions:
o slope, and,
o aspect;
• Fuel models, and;
• Winds:
o prevailing winds, and
o extraordinary winds.
In terms of producing high WHLs within the FPAA it was observed that the fuel model type present at a subject location had the most apparently correlative relationship. This relationship was clear enough to use the presence of certain fuel model types (forest- and woodland-related) as an initial indicator of higher risk situations. The presence of terrain characteristics such as slope (due to the “up-hill” augmentation of spread rate) and aspect (due to influence over the type and condition of occupying vegetation) was considered as a second priority influence. Wind factors were considered to have relatively the lowest level of influence as 1) the weather station information did not show typical wind directions that would add higher level of risk when acting in concert with the other setting elements, and 2) the other two categories of winds, diurnal and “fire storm-related”, showed a low predictability of occurrence that would increase the uncertainty of wildfire event predictability Mapping Wildfire Hazard Levels for the FPAA
The FPAA map showed that:
• Approximately 95% of the CPAA has been designated as having a “Low” WHL • Within the CPAA the high two WHL designations are associated with the vegetated drainages and small areas that are portions of the elevated terrain • The 22,471-acre EPAA has a fairly equal distribution of the three WHLs • In the EPAA the “Medium” and “High” WHLs are associated with the elevated terrain.
Special Resource Situations
In addition to the determination of regional WHLs, and their distribution within the FPAA, this assessment also addressed the vulnerability to involvement in, and/or undesirable impacts from, a wildfire incident for four special resource/feature situations:
Camarillo Wildfire Hazard Assessment
52 • Roads;
• Communities Vulnerable to Elevated Levels of Impacts from Wildfire; • High tension electrical lines, and;
• Vegetated drainages.
Roads with Elevated Loss of Function Vulnerability
As previously stated, where wildfire is an issue, loss of a road’s ability to provide access for emergency response and/or public evacuation, needs to be addressed via the making, or adjustment, of pertinent policy, statutes, regulatory codes, and practices. With respect to assessing the potential for loss of a road’s ability to function (“LOF”), due to involvement in a wildfire event, 24 roads, with a lineal measurement of 71.52 miles, were surveyed for conditions that could lead to such a loss (see Figures 23 and 24 and Table 13). The survey employed identification criteria based primarily on proximity to fuels models that could produce more destructive wildfire behaviors and each individual road segment was designated as having a High, Medium, or Low LOF risk. Each mapped segment was attributed with both a risk designation but also with whether it was in the CPAA or EPAA.
The primary purpose of this activity was to identify specific locations were a LOF could be critical to the success of a response or evacuation effort and enable planning for, and implementing, mitigating actions.
Of the 24 roads addressed only one showed one, or more, segments in the “High” LOF risk level:
Ventura Freeway with 1.2 miles within the CPSA and 0.29 mile in the EPAA. The identified segments were located in the stretch of road running through the mountains between Camarillo and the Thousand Oaks area. Should mitigation be considered it will, in all likelihood, require collaborative planning with Caltrans regarding its right-of-way, and the owners (public and private) of the surrounding lands.
Six of the 24 roads (E. Los Angeles Ave., Earl Joseph Dr., Mission Oaks Rd., Santa Rosa Rd., Upland Rd., and Ventura Freeway) showed LOF risks in the “Medium” category. These segments covered 2.79 miles in the CPSA and 3.44 miles in the EPAA. For this particular category implementing mitigation actions will be based on questions of criticality of the LOF if a wildfire should occur.
Communities Vulnerable to Elevated Levels of Impacts from Wildfire Communities typically addressed in this sensitivity category are those 1) in direct contact with setting elements associated with adverse wildfire behavior, and 2) access restrictions that can adversely affect both access for emergency response and evacuation. Six residential developments, encompassing a total of 422.5 acres, were identified whose boundaries were well-defined. A seventh example was a sprawling 723-acre, less well-defined community in the northwestern portion of the FPAA (See Figure 24).
Although a more in-depth analysis of the nature and intensity of wildfire hazard was not within the scope for this project, these communities (and those subsequently identified) were identified as potentially warranting further, and more site and purpose-specific, evaluation. All but one of these communities were located outside of the CPSA; the exception being the Ridge View Rd./Adhor Ln. development.
Camarillo Wildfire Hazard Assessment
53 None of these developments are in close proximity to lands identified as “High” WHL, again with the exception of the Ridge View/Adhor development. Further evaluation of the developments outside of the CPSA, should it be deemed warranted, would require collaboration with the County of Ventura and Ventura County Fire Department.
High Tension Electrical Lines
This feature (a two-line set estimated at 230 kV and a feeder line) runs approximately 10 miles through the southeast corner of the FPAA. As mentioned previously, this is a critical infrastructure feature that is vulnerable to damage if there is a wildfire event and can be a source of ignition as well. The line’s position is to the east of the ridgeline of the mountains encircling the CPAA so an ignition within the corridor could have an up-hill run to the crest area and ultimately jeopardize the CPAA. Figure 29 shows an enlarged map showing the location of the HTEL and feeder line corridors (wider red and cyan lines, respectively) over the LANDFIRE results for predicted flame lengths. A significant majority of the corridor passes through fuel models that are expected to generate flame lengths up to 11 feet, which if the lines follow industry standards for ground separation, would not, reasonably, pose a risk to the lines.
However, there are locations where the lines pass over drainages where fuel models (those associated with tree species-dominated gallery formations) that can generate flame lengths up to twenty-five feet which could pose problems if the separation distance is not adequate. In order to determine if the combination of the characteristics of the fuel models under the lines and the hanging distance above the surface poses a significant risk further study would be required.
Figure 29. High Tension Electrical Transmission Line Corridors Within the FPAA
Camarillo Wildfire Hazard Assessment
54 Vegetated Drainages
As previously discussed, these features can be both a pathway for a wildfire to move across an urban landscape and can provide locations where human activity can result in wildfire ignitions. Management of these features for wildfire risk reduction can be complicated due to social, legal, and administrative implications. Historically, from the standpoint of wildfire protections, these features have not been the focus of policy or development of “best management practices” because many of them are under public agency, or special district, control and may have strict conservation mandates that don’t allow the vegetation management needed for wildfire risk reduction.
The mapping effort identified 640 acres of surface occupied by these features; 160.5 acres in the CPAA and 482.5 in the EPAA. The features had linear measures that ranged between 1.5 miles and 9.5 miles and had insignificant contact with the roads addressed in the LOF effort. Additional study would be warranted at the few points of contact with critical roads to determine if wildfire risk reduction mitigation could be warranted.
CONCLUSIONS and RECOMMENDATIONS
Conclusions and Recommendations
Summarized below are the conclusions and recommendations from this wildfire hazard risk assessment.
Regional Wildfire Hazard Risk Levels
Regional Wildfire Hazard Risk Levels – Conclusions
The results generated from this assessment of WHL are typical of a regionally oriented effort where there is 1) a relatively large area involved, 2) the necessity to use a relatively large minimum mapping area, 3) data collected is primarily through the use of remotely sensed databases, and 4) comprehensive ground verification is not possible. The results typically generated by this type of assessment are most effectively used in policy formulation, large-area planning efforts, identification of administrative approaches, and Conduct more in-depth analyses of wildfire fuel model-related roles of agricultural uses employing woody species (orchards, vineyards, bush crops, etc.). Suggested follow-on studies would address wildfire behavior modeling aspects, the associated level of significance attached to hazard and risk issues, assessing the adequacy of the current body of policy/practice to address planning and operational needs, and, coordination between land management entities.
In consideration of:
• The City of Camarillo’s topographic setting;
• Within the CPAA, a very low percentage of surface occupation by wildfire-related fuel models capable of generating dangerous fire behavior;
• Relative absence of predictable prevailing winds that could exacerbate wildfire behavior; • The possibility of wind-driven wildfires approaching the CPAA under Santa Ana conditions, and;
Camarillo Wildfire Hazard Assessment
55 • Location within the FPAA, but outside of the CPAA, of fuel models that can generate more dangerous fire behaviors;
it is reasonable to conclude that overall hazard levels to resources in the CPSA would be in a Low-to- Low Medium category.
Regional Wildfire Hazard Risk Levels – Recommendations
Recommendation: RWHR 01 – Multiphase Analysis
The preparation of a regional database, generally characterized as a Phase1 activity, has associated advantages but also limitations. The principal advantage is that the generated products and information is applicable over large surface areas and is suitable for use in long range planning, creation of policy and regulatory codes, and generating strategic-level programs. The principal limitation is the information generated lacks the detail to guide operational policies and practices; a vital element in addressing wildfire issues. In order to bridge this gap another type of analysis can be implemented once Phase 1 products are in hand. Using the Phase 1 products as a guide additional study can be focused on smaller, less complex, areas. Having to address more limited areas can require lesser amounts of resources to complete and can be focused on generating the information that can support operational needs.
In this assessment the product generated at the initial stage is a geo-referenced database covering 35,079 acres, whose primary attribute breakdown was into areas of homogeneous WHL. A reasonable second phase study could focus on the 9,847 acres that were determined to have a “High” hazard rating, that occupies 28.1% of the FPAA. Narrowing the focus on this WHL, which 1) exerted the most significant influence on fire behavior region-wide, 2) addressed an area where numerous wildfires have occurred historically, and 3) provides a key pathway for wildfires driven by Santa Ana winds to approach the CPAA. Additional benefits would be that 1) the second-phase area is now small enough to support a minimum mapping area that can provide more detail for the ground conditions, and 2) will enable planners and practitioners to establish links to appropriate mitigating actions. Based on the results of the current assessment it is recommended that the following subject areas be considered for second phase efforts:
• The specific setting element mechanics that model the Santa Ana wind situation and how they relate to developing mitigation measures;
• The lands determined to have a “High” level of wildfire hazard; • The operational relationships between the elements of the emergency response apparatus and lands determined to have “Moderate” and/or “High” WHLs;
• The setting elements around road segments that have been lands determined to have “Moderate” and/or “High” LOF risks;
• The setting elements around the mapped wooded drainages; • The communities having elevated vulnerability to wildfire effects; • The setting elements around, and within, the HTEL, and;
Camarillo Wildfire Hazard Assessment
56 Recommendation: RWHR 02 – Assessment of the Multipliers Used Conduct an analysis of the various multiplier factors used in the WHL determination procedures to assess how well they are modeling the Camarillo situation. This process would solicit the input from a spectrum of potential users of both the Phase 1 and 2 products
Recommendation: RWHR 02 – Assess the Process for Evaluating Special Agricultural Situations Conduct more in-depth analyses of wildfire fuel model-related roles of agricultural uses employing woody species (orchards, vineyards, bush crops, etc.). Studies would address wildfire behavior modeling aspects, the associated level of significance attached to hazard and risk issues, and as assessing the adequacy of the current body of policy/practice to address planning and operational needs.
Reccomendation: RWHR 03 – Assess the Process for Evaluating Urban Land Uses Conduct a study of the wildfire behavior implication of land uses not addressed in standard wildland fuel modelling systems. For example, lands occupied by suburban residential, higher-density urban residential and commercial uses, typically have a mix of fuels that could support wildfire ignition and travel across the surface. Theses fuels are typically the results of landscaping private properties and/or imbedded public parks and reserves and involve expanses of grass, scrub, brush, woodland, and forest formations. These land uses which have surfaces that are occupied by a mix of truly non-flammable (pavements, bare ground, appropriately roofed structures, etc.) and flammable surface conditions have not been adequately studied and would be a reasonable Phase 2 study using the database information produced by this regional Phase 1 effort.
Special Feature/Resource Conditions Situations
Wildfire Hazard and Risks Associated with Santa Ana Conditions Wildfire Hazard and Risks Associated with Santa Ana Conditions - Conclusions Research, and the collection of empirical data that was part of this project analysis, showed that the City of Camarillo could be imperiled by wind driven fires under Santa Ana conditions. The east-to-west winds characterizing these conditions align with the system of mountainous ridges that form a framework around the City increasing the possibility of wildfire impacts. Furthermore, these mountainous areas are where the fuel models that can generate more extreme wildfire behaviors are located so there is a fuel model-related mechanism in-place for wildfire to move towards the Camarillo area.
Wildfire Hazard and Risks Associated with Santa Ana Conditions - Recommendations Recommendation: SA 01 – Early Warning System
It is recommended that more in-depth consideration be given to developing an “early warning system”, in collaboration with appropriate stakeholders, that can be deployed as Santa Ana conditions begin to develop. A key to such an effort would lie with developing relationships with wildfire/structure emergency fire services who employ wind information in their planning and operational procedures. It is suggested such an effort start with such entities in the Valencia/Castaic Junction and include all those in the Highway 126 and Highway 118 corridors to the east of the FPAA.
Camarillo Wildfire Hazard Assessment
57 Recommendation: SA 02 – Detailed Wildfire Movement Analysis for Elevated Terrain Zones It is recommended that consideration be given to preparing a wildfire movement assessment and mitigation plan for the system of mountain ridges flanking the Santa Rosa Valley from the Simi Valley area west to the crest of the mountains surrounding the CPSA. The analysis would focus on 1) a detailed mapping of fuel models (their nature and continuity) in order to predict likely wildfire movement patterns under easterly winds, 2) the property ownerships present, 3) potential movement control mitigation activities and 4) emergency wildfire response entities (location, institutional capacity, and contact information).
Wildfire Hazard Risks Associated with Agricultural Operations Wildfire Hazard and Risks Associated with Agricultural Operations - Conclusions As it can be discerned from Figure 27 certain agricultural uses (scrub/brush producers, vineyard, and orchards) are associated with the Medium WHL. At the time of completion of this wildfire assessment it was apparent the current body of policy and practices did not accurately reflect the role of these types of agricultural uses when addressing wildfire issues. When completing the cross-walk from vegetation associations to fuel models it became apparent that orchards and vineyards acted more like natural shrub/brush or woodland associations than what is expected from their classification as a non-burnable agricultural land use.
Wildfire Hazard and Risks Associated with Agricultural Operations – Recommendations Recommendation: AO 01
It is recommended that the wildfire behavior characteristics of these special agricultural uses be given greater consideration when developing wildfire mitigation policy, guiding legislation, regulatory code, and in-field emergency response planning and practice. This would be supported by designing and completing a detailed study of wildfire behavior that would come from fuel model characteristics exhibited by these agricultural formations
Road Vulnerability to Wildfire-Caused Loss of Function
Road Vulnerability to Wildfire-Caused Loss of Function – Conclusions It was determined that within the CPSA road vulnerability to wildfire-caused loss of function did not rise to a level of significance. All instances of these conditions were located outside of the CPSA but within the FPAA and could pose both significant levels of hazard and risk to resources in the CPSA in the event that a wildfire transits the FPAA and enters to CPSA.
Road Vulnerability to Wildfire-Caused Loss of Function – Recommendations Recommendation: LOF 01 – Conduct a Focused Assessment for Vulnerable Roads Conduct a more detailed study of the fuel model conditions where the risk of LOF is at a Medium or High level. Determine the ignition mechanisms, potential approach pathways to the more vulnerable road sections, land ownerships involved, and identify mitigating action opportunities
Camarillo Wildfire Hazard Assessment
58 At Risk Communities – Those With Elevated Vulnerability to Wildfire Communities with Elevated Vulnerability to Wildfire – Conclusions Although the surface area of At Risk Communities (“ARC”) is relatively small at 1,145 acres (3.3% of the FPAA) the values involved, including human lives and livelihoods, community resources, social and political condition, cannot be undervalued. The location of the identified communities does place them in more isolated and vulnerable, positions with respect to both topographic and prevailing wind influences, and further study would be beneficial.
Communities with Elevated Vulnerability to Wildfire - Recommendations Recommendation: ARC 01 – Conduct a Focused Assessment for Vulnerable Roads Conduct a more detailed study that addresses 1) the fuel model configuration, 2) emergency response access conditions, and 3) potential effect of extraordinary easterly winds. Determine the ignition mechanisms, potential approach pathways to the more vulnerable road sections, potential movement within the community boundaries, land ownerships involved, status of community-level disaster response, and potential mitigating action opportunities.
Vegetated Drainages
Vegetated Drainages – Conclusions
It was determined that a total of 643 acres of surface within the FPAA (1.8%) was occupied by this feature. Approximately 160 acres were located within the CPSA and the remainder, 482 acres occurred within the FPAA. Once again, this feature occupies a small surface area but can have the potential for significant influences over the levels of both wildfire hazard and risk. It is highly likely that management of the vegetation in these areas is guided by the 1) the specific goals and objectives of the entity with jurisdictional responsibility, and 2) the presence of special status plant communities, and wildfire mitigation actions have not been given significant attention.
Within the project study area the primary example of these conditions are those associated with Calleguas Creek. A brief case study of this creek was conducted relative to wildfire hazard, risk, and management implications and the results are summarized in the bullets below:
• The gallery riparian formations located along watercourses exhibit the characteristics of multi-storied, woodland fuel models with moderate-to-heavy fuel loadings, and could produce more extreme fire behaviors characterized by fire front advances that would be moderately resistant to control, flame lengths in a range of 10 - 20 feet, moderate-to-high residence times and intensities, ability to crown, and moderate production of embers; • Multiple land management entities were involved in vegetation management including the Ventura County Flood Control District
38 and the Channel Islands Regional Park (California
State University39. The Channel Islands Park did experience a significant wildfire event in 2013 and, just prior in 2012, formulated a Park Master Planning Committee (PMPC) with its purpose being to provide a forum for PMPC members to discuss and make recommendations
38 Ventura County, Flood Control District.
39 CSU, Channel Islands Regional Park.
Camarillo Wildfire Hazard Assessment
59 for a master plan that reflects the University's strategic plan, particularly as it relates to environmental sustainability and to develop curricular and co-curricular programs for the University and community use and recreation. No publicly available information was found that indicated the current status of the park master plan development, but this is the type of planning opportunity that needs to be identified with regard to the inclusion of wildfire issues in the planning process, and;
• Although wildfire and fuels management were addressed in the Safety Element of the City of Camarillo’s General Plan40 no specific operational wildfire hazard mitigation standards have been addressed in policy or regulatory materials by either the City or Ventura County.
Vegetated Drainages - Recommendations
Recommendation: WD 01 – Conduct a More Detailed Fuel Model Assessment Within the 643 acres occupied by these conditions conduct a more detailed study that addresses 1) the floristic characteristics of the involved vegetation formations, 2) the corresponding fuel model configurations, 3) emergency response access conditions, and 4) proximal resources at risk.
Recommendation: WD 02 – Initiate Collaborative Efforts with Regard to Mitigation Prepare a list of entities with jurisdiction over vegetation management and initiate contact regarding possible planning-level collaboration to address wildfire concerns.
40 City of Camarillo. 2004.
Camarillo Wildfire Hazard Assessment
60 References
Anderson, Hal E. Aids to Determining Fuel Models for Estimating Fire Behavior. United States Department of Agriculture Forest Service Intermountain Forest and Range Experiment Station, Ogden, UT. General Technical Report INT-122. April 1982. [https://www.fs.usda.gov/rm/pubs_int/int_gtr122.pdf]
California Fire Code. California Code of Regulations, Title 24, Part 9, §§ 901. – 917.1.
California Fire Code, Chapter 49, §§ 4901 – 4908.9.1
California Department of Forestry and Fire Protection (CAL FIRE). 2017 Incident Archive. Accessed April 16, 2023. [
https://www.fire.ca.gov/incidents/2017]
California Department of Forestry and Fire Protection (CAL FIRE). Top 20 Largest California Wildfires. October 24, 2022. [
https://34c031f8-c9fd-4018-8c5a-4159cdff6b0d-cdn-endpoint.azureedge.net/- /media/calfire-website/our-impact/fire-statistics/featureditems/top20_acres.pdf] California Department of Transportation. California Road System-Functional Classification. Map Grid Nos. 8H52, 8H53, 8J12, and 8J13. January 28, 2022.
[
https://caltrans.maps.arcgis.com/apps/webappviewer/index.html?id=026e830c914c495797c969a3e5668538]
California Department of Justice, Office of the Attorney General. Rob Bonta – Newsletter. [https://oag.ca.gov/environment/impact]
California Environmental Quality Act (CEQA) Guidelines. Public Resources Code (PRC), Division 13, Sections 21000-21177.
California Environmental Quality Act (CEQA). Guidelines for Implementation of the California Environmental Quality Act. California Code of Regulations, Title 14, Division 6, Chapter 3, Sections 15000-15387 and Appendices A-K.
California State University-Channel Islands. CSU Channel Islands University Park 2016 Vision Plan. https://www.csuci.edu/cipark/documents/17-03-15-vision-plan.pdf
Calleguas Municipal Water District
CalVeg
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=153398&inline
City of Camarillo, Department of Community Development. 2021 General Plan – Annual Progress Report. April 1, 2022.
https://cms7files.revize.com/camarilloca/DEPArtments/Community%20Development/General%20Plan/2021%20GPA%20R eport%20w_attachments.pdf
City of Camarillo, Department of Community Development. General Plan. https://www.ci.camarillo.ca.us/dEPArtments/community_development/general_plan.php
City of Camarillo, Department of Community Development. Request for Proposals – Update to the City of Camarillo Safety Element. September 20, 2021.
Camarillo Wildfire Hazard Assessment
61 Dettinger, Michael, Holly Alpert, John Battles, Jonathan Kusel, Hugh Saford, Dorian Fougeres, Clarke Knight, Lauren Miller, Sarah Sawyer. 2018. Sierra Nevada Summary Report. California’s Fourth Climate Change Assessment. Publication number: SUM-CCCA4-2018-004. [https://www.energy.ca.gov/sites/default/files/2019-11/Reg_Report-SUM-CCCA4-2018-004_SierraNevada_ADA.pdf]
Fovell, Robert. Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles. The Sant Ana Winds. FAQ. May 2014.
[
http://people.atmos.ucla.edu/fovell/ASother/mm5/SantaAna/santa_ana_faq.html]
Google Earth. Google Earth Pro, Version 7.3.6.9345. December 29, 2022.
Interagency Fuel Treatment Decision Support System. Report: Landscape Fire Behavior - Camarillo Area of Concern. March 4, 2023.
Interagency Fuel Treatment Decision Support System. Report: Landscape Summary – Camarillo Area of Concern. March 32, 2023.
Interagency Fuel Treatment Decision Support System. LANDFIRE Version LF 2020. Accessed March 23, 2023.
Iowa State University, Iowa Environmental Mesonet. Wind Roses. Accessed 5/15/23. https://mesonet.agron.iastate.edu
- Miller Ranch RAWS [MLXC1]
https://mesonet.agron.iastate.edu/sites/windrose.phtml?station=MLXC1&network=CA_DCP - South Mountain West [SMNC1]
https://mesonet.agron.iastate.edu/sites/windrose.phtml?station=SMNC1&network=CA_DCP - Thousand Oaks Civic Center [TOCC1]
https://mesonet.agron.iastate.edu/sites/windrose.phtml?station=TOCC1&network=CA_DCP
Magney, David. Flora of Ventura County - Ventura County Biogeography. March 14, 2023. [https://www.venturaflora.com/files/vcbiogeography.htm]
Peel, M. C.; Finlayson, B. L.; McMahon, T. A. Updated World Map of the Koppen-Geigen Climate Classification. March 1, 2007.
Pleasant Valley Mutual Water Company. PVMWC System Improvement Projects. 2020-2024. https://www.pvmwc.com/_files/ugd/a4b91e_13781370a71e4e30b5b81d489d75d008.pdf
Royal Meterological Society. Met Matters: The Beufort Wind Scale. Undated. Access April 18, 2023. https://www.rmets.org/metmatters/beaufort-wind-
scale#:~:text=The%20Beaufort%20Scale%20is%20an,hour%20and%20kilometres%20per%20hour.
Scott. Joe H. and R.E. Burgan. Standard Fire Behavior Fuel Models: A Comprehensive
Camarillo Wildfire Hazard Assessment
62 Set for Use with Rothermel’s Surface Fire Spread Model. United States Department of Agriculture, Forest Service, Rocky Mountain Research Station. General Technical Report RMRS-GTR-153. June 2005. https://gacc.nifc.gov/oncc/docs/40Standard%20Fire%20Behavior%20Fuel%20Models.pdf
Scott. Joe H. and E.D Reinhardt. Assessing Crown Fire Potential by Linking Models of Surface and Crown Fire Behavior. United States Department of Agriculture Forest Service, Rocky Mountain Research Station. Research Paper RMRS-RP-29. September 2001.
State of California, Legislative Analyst’s Office. Climate Change Impacts Across California – Crosscutting Issues. April 5, 2022.
https://lao.ca.gov/Publications/Report/4575
State of California, Office of the State Fire Marshal (OSFM). Fire Hazard Severity Zones (FHSZ):
Explore Fire Hazard Severity Zones. Accessed: January 15, 2023. [
https://osfm.fire.ca.gov/divisions/community-wildfire-prEPAredness-and-mitigation/wildfire-prEPAredness/fire-hazard- severity-zones/]
United States Department of Transportation, Federal Highway Administration, Office of Planning, Environment, and Realty. Planning Process - Highway Functional Classification Concepts, Criteria and Procedures. September, 2013.
[
https://www.fhwa.dot.gov/planning/processes/statewide/related/highway_functional_classifications/section00.cfm]
United States Department of Agriculture, Forest Service, Pacific Southwest Region (#5). CalVeg Crosswalk to CWHL. Accessed 10/24/2022.
[
https://www.fs.usda.gov/detail/r5/landmanagement/resourcemanagement/?cid=fsbdev3_046735]
United States Department of Agriculture, Forest Service, Pacific Southwest Region (#5). CalVeg System: Table 37. Vegetation Cover Types. Accessed 10/24/2022. [https://www.fs.usda.gov/detail/r5/landmanagement/resourcemanagement/?cid=fsbdev3_048020]
United States Department of Agriculture, Forest Service, Pacific Southwest Region (#5). CALVEG Mapping Zones. Accessed: December 17, 2022.
https://www.fs.usda.gov/detail/r5/landmanagement/resourcemanagement/?cid=stelprdb5347192
USDI/Interagency Fuel Treatment Decision Support System (IFTDSS). LANDFIRE Model https://www.landfire.gov/about.php
USDI/Interagency Fuel Treatment Decision Support System (IFTDSS). Camarilla Area of Concern- Landscape Report. March 13, 2023.
United States Department of the Interior, National Park Service. Wildland Fire-Incident Command System Levels. February 13, 2017.
https://www.nps.gov/articles/wildland-fire-incident-command-system-levels.htm
United State Geological Service-National Park Service, USGS-NPS Vegetation Mapping Program.
Santa Monica Mountains National Recreation Area – Photo Interpretation Report. May 23, 2007. https://docs.vcrma.org/images/pdf/planning/bio/SM_Mountains_Photo_Interp_Rpt.pdf
Camarillo Wildfire Hazard Assessment
63 Ventura County Flood Control District. Comprehensive Plan for Flood Control – List of Channels Within the Comprehensive Plan of the Ventura County Flood Control District as of October 4, 1994.
Table II, Zone 3.
https://www.vcpublicworks.org/wp-content/uploads/2018/12/VCFCD-Channels-List.pdf
Ventura County, Public Works Department. Ventura County Floodplain Management Ordinance, Ordinance No. 4521(1
st and 2nd halves), March 27, 2018.
https://www.vcpublicworks.org/wp-content/uploads/2018/12/1st-half-Flood-Plain-Management-Ordinance-4521.pdf and
https://www.vcpublicworks.org/wp-content/uploads/2018/12/2nd-half-Flood-Plain-Management-Ordinance-4521.pdf
Ventura County, Public Works Department. Weathering the Storm – Disaster Preparedness. Accessed:
April 15, 2023.
https://www.vcpublicworks.org/wp/policiesandordinances/
Weather Spark. Climate and Average Weather Year Round in Camarillo. Accessed: April 4, 2023. [https://weatherspark.com/y/1426/Average-Weather-in-Camarillo-California-United-States-Year-Round]
The Brush Fire Foundation, Inc. Fire Behavior. Accessed: April 10, 2023. https://www.thebushfirefoundation.org/how-fire-behaves/