Marin County Community Wildfire Protection Plan 2016
FIRESafe MARIN is pleased to announce the publication of the 2016 Marin County Community Wildfire Protection Plan. This document represents more than a year of work by a diverse group of community stakeholders, fire officials, and wildfire science experts to produce an updated CWPP which broadly addresses wildfire risk and hazard in Marin County and provides a framework for future mitigation efforts.
CWPp Maps and Data
Disclaimer: The data displayed on the CWPP online map is for informational use only. FIRESafe MARIN asks that viewers be cautious when interpreting the results - non fire professionals should seek advice from wildfire experts before drawing conclusions or interpreting data. For example, in many views, green is used to indicate lower flame lengths and rate of spread. This does not indicate a safety zone or area free from fire risk. Wildfire science is complex, and the modeled flame lengths, rate of spread, and composite mapping are not necessarily indicators of risk to infrastructure or populations. Contact local fire jurisdiction for additional assistance and interpretation.
For additional information see the CWPP document
To improve upon the currently available state-level fire hazard assessment information, an independent hazard, asset, risk assessment was performed to help identify and prioritize areas within the county that are potentially at a high threat from wildfire based on more recent fuels data, advanced modeling techniques, and local input. The assessment was performed by modeling potential fire behavior and the probability or likelihood that an area will burn given an ignition.
Next, the fire modeling output was combined with areas of concern and assets at risk. Composite maps were generated indicating relative potential fire hazards throughout the county.
Additionally, fire behavior modeling was conducted under two fire weather scenarios. Two fire weather scenarios were chosen to represent annual wildfire conditions for an average fire season and a fire season under extreme fire conditions. The average fire season scenario was created by summarizing the weather and fuel moisture parameters from April through October (a typical fire season), and was used to represent the fire weather conditions during a typical summer day in Marin County. The extreme fire conditions scenario was created using the 97th percentile weather data from July through October, and represents the hottest and driest time periods during the summer months when fire behavior would be the most intense and difficult to control.
The information below describes each map layer within this application and explains how it’s used in the risk assessment process.
Marin Fuel Model 5m.tif: As part of the development of the CWPP, an updated, high-resolution (5 x 5 meter) gridded vegetation map was developed using a combination of vegetation data provided by local land management agencies and recently obtained LiDAR measurements (see Section 2.2 and Appendix A for the CWPP). The 5 x 5 meter data were used as input to FlamMap for modeling potential fire behavior.
2010 Census Block Population (people / square mile): Population density data for Marin County were acquired from the U.S. Census Bureau. The data were mapped and used in the hazard, value, risk assessment to identify populated areas, which represent areas with high structure density. These data were used as a surrogate for representing areas of high asset value that are important from a fire protection perspective.
Average Fire Season – Flame Length (feet) / Extreme Fire Conditions - Flame Length (feet): The FlamMap fire behavior model was used to model flame length under each fire weather scenario. Flame length is commonly used as a gauge of fire potential because it provides an indicator of possible fire behavior from a suppression perspective. Section 4.2.5 of the CWPP provides additional information on the flame length.
Average Fire Season - Rate of Spread (feet/minute) / Extreme Fire Conditions - Rate of Spread (feet/minute): Rate of spread is an indicator of how rapidly a fire might spread, and is defined as the rate of forward spread of the fire head expressed in feet per minute. FlamMap runs were performed for the two weather scenarios using the custom fuel model data developed for Marin County and topographical data (slope, aspect, and elevation).
Average Fire Season- Composite Map / Extreme Fire Conditions - Composite Map: The composite maps from the hazard, value, risk assessment were composed using a suitability modeling approach. Suitability modeling is a GIS-based method used for identifying areas based on specific criteria. For this work, suitability modeling was used to identify areas of high fire hazard (or concern) based on fire behavior potentials, population density, and proximity to areas of concern. The Environmental Systems Research Institute (ESRI) ArcGIS software, Spatial Analyst, was used for this analysis. Spatial Analyst is a raster- or grid-based software package that provides a platform for developing and manipulating gridded data. Spatial Analyst can be used to develop suitability models that produce maps highlighting “suitable” geographic areas based on defined model criteria and weighting schemes.
Population density, flame length, and rate of spread maps (Described above) were merged and processed to identify areas that have very high population density, flame lengths, and rate of spread. These data layers show the composite maps for each fire weather scenario; red and orange show areas of very high to high population density, flame length, and rate of spread. These are areas of high asset value where fire behavior is likely to be extreme.
Fire Service Area: Boundary file for each Marin County fire service area. This data layer was included to allow users to click on and zoom to a desired fire service area.
What is a Community Wildfire Protection Plan (CWPP)?
In 2015, CAL FIRE awarded FIRESafe MARIN a $123,200 grant from the SRA Fire Prevention Fee Fund to update the 2005 Marin County Community Wildfire Protection Plan, and integrate it with the Marin County Fire Department Unit Strategic Fire Plan.
A science-based hazard, asset, risk assessment was performed using up-to-date, high resolution topography and fuels information combined with local fuel moisture and weather data. The assessment was focused on identifying areas of concern throughout the county and beginning to prioritize areas where wildfire threat is greatest. Hazard mitigation efforts can then be focused to address specific issues in the areas of greatest concern (see Sections 4 and 5).
Marin County will reduce wildland fire hazard using a collaborative and integrated approach that includes the following strategies (see Section 8):
- Pre-fire planning.
- Public education and outreach to promote and implement fire adapted community practices.
- Vegetation management and fuel reduction at the county and community levels.
- Reducing structure ignitability by promoting and enforcing building codes, ordinances, and statutes.
This document provides a framework for future collaboration that can be used to identify, prioritize, implement, and monitor hazard reduction activities throughout the county. It is intended to be a living document that will be updated periodically by FIRESafe MARIN and the Marin County Fire Department (MCFD) in collaboration with a broader group of county stakeholders.
This document is also intended to support the California Fire Plan and CAL FIRE’s Unit Strategic Fire Plan. While this CWPP broadly covers the entire county, this plan supports and encourages more focused plans for wildfire protection at the city, community, and neighborhood scales.
The Marin County Community Wildfire Protection Plan was developed through a collaborative process during a year-long process with input from public and governmental stakeholders.
Sonoma Technology, Inc (STI)
Development of the Marin County Community Wildfire Protection Plan
Clients: FIRESafe MARIN, Marin County Fire Department
With California experiencing one of the most severe droughts in decades and dealing with a massive accumulation of fuel (vegetation available to burn), STI worked with FIRESafe MARIN and the Marin County Fire Department (MCFD) to develop the Marin County Community Wildfire Protection Plan (CWPP). The CWPP provides a framework to help mitigate wildfire hazard in Marin County, California. The CWPP provides a scientifically based assessment of wildfire risks in the county’s wildland-urban interface (WUI), and includes an action plan with goals and recommendations.Marin County is home to 23 communities listed on CAL FIRE’s
Marin County is home to 23 communities listed on CAL FIRE’s Communities at Risk list, and approximately 80% of the land area in the county is designated as having moderate to very high fire hazard severity ratings. Structures located in the WUI—where homes are intermixed with open space and wildland vegetation—are at the highest risk from wildfires due to the density of vegetation and limited access for firefighters. A recent assessment by the MCFD revealed there are approximately 69,000 living units valued at $59 billion within Marin County’s WUI. Proper planning and collaboration across the County’s fire districts is essential to protect these residents and their property.During the CWPP development process, STI and FireSAFE MARIN sought input from the county’s 20 fire agencies and associations and held a series of public meetings to make sure the concerns of County residents were integrated into the CWPP. STI’s team of wildfire science experts used fire behavior modeling to develop a hazard, asset, and risk assessment using high-resolution fuels information to identify areas of
During the CWPP development process, STI and FireSAFE MARIN sought input from the county’s 20 fire agencies and associations and held a series of public meetings to make sure the concerns of County residents were integrated into the CWPP. STI’s team of wildfire science experts used fire behavior modeling to develop a hazard, asset, and risk assessment using high-resolution fuels information to identify areas of significant fire hazard. FireSAFE MARIN and its stakeholders then created an action plan with key goals and action items for continued fire protection planning efforts throughout the county.