Identifying and Managing Wildfire Risk in California

by Lisa Davison, Environmental Planner at M-Group

Home surrounded by wildland that survived a fire due to good defensible space. Source: 2010 Strategic Fire Plan for California, April 2016

California experienced one of the most devastating wildfire seasons in 2017, with a total of 7,117 fires burning 505,956 acres. The fires in Sonoma and Napa counties burned 146,647 acres and destroyed nearly 8,000 structures in October, accounting for approximately 30 percent of the acreage burned in 2017. The fires in Ventura, Santa Barbara, and Los Angeles counties burned 303,561 acres and destroyed 1,120 structures in December, and accounted for approximately 60 percent of the acreage burned in 2017.

California is at great risk from wildfires because of its particular combination of weather, topography, and native vegetation. Southern California has the added risk of the Santa Ana winds that appear in the spring and late fall. Fire risks have increased with drought conditions, population growth, and increased development within the wildland-urban interface.

This article describes the various entities that are responsible for identifying and managing wildfire risk in California in order to minimize the loss of life and property from wildland fires in the future.

State-level Responsibilities

The California Department of Forestry and Fire Protection (CAL FIRE), State Board of Forestry and Fire Protection, and the California Building Code serve as the building blocks for identifying and managing wildfire risk at the state level.

CAL FIRE Mapping

CAL FIRE is required by law to map areas of significant fire hazards based on fuels, terrain, weather, and other relevant factors. CAL FIRE’s Statewide and County maps (adopted November 2007) depict Fire Hazard Severity Zones (FHSZs)[1] that are within the State Responsibility Area (SRA). The SRA identifies where the State of California is financially responsible for the prevention and suppression of wildfires. The SRA does not include lands within city boundaries or in federal ownership. The FHSZs in the SRA are further classified as being Moderate, High, or Very High.

[1] The FHSZs identify fire hazard, not fire risk. “Hazard” is based on the physical conditions that give a likelihood that an area will burn over a 30 to 50-year period without considering modifications such as fuel reduction efforts. “Risk” is the potential damage a fire can do to the area under existing conditions, including any modifications such as defensible space, irrigation and sprinklers, and ignition resistant building construction which can reduce fire risk.

In addition, CAL FIRE has prepared recommendations for Very High FHSZs in those areas where local governments have financial responsibility for wildland fire protection, known as Local Responsibility Areas (LRA). Only lands zoned as Very High FHSZ are identified within the LRA. In 2008, CAL FIRE transmitted those recommendations to all local agencies with identified Very High FHSZs. However, this process has its limitations. First, because CAL FIRE only transmits the areas identified as Very High FHSZs to the local agencies, there could be some Moderate or High FHSZs within the LRA that are not being identified. Second, the CAL FIRE zoning designations do not go into effect until they are adopted by ordinance by local agencies. Last, the maps were created in 2008 and reflect outdated information. CAL FIRE is currently in the process of updating the FHSZ maps (Feb 2018).

Currently, CAL FIRE is investigating methods for estimating the likelihood of fire occurrence across the State in the coming decades. As part of this effort, CAL FIRE has created a map of annual fire probability for the period 2026-2050. This map is intended for use in the quantification of GHG benefits of fuel reduction activities funded under the 2016-17 Greenhouse Gas Reduction Fund Forest Health Program. 

Strategic Fire Plan for California

The 2010 Strategic Fire Plan for California (revised April 2016) was developed by the State Board of Forestry and Fire Protection and CAL FIRE. The plan’s vision is to support a natural environment that is more resilient and ensure that man-made assets are more resistant to the occurrence and effects of wildland fire. The plan identifies goals and objectives that are critical to reducing and preventing the impacts of fire, which revolve around both suppression and fire prevention efforts.

The first goal of the plan relates to the identification and evaluation of wildland fire hazards and recognizing the life, property and natural resource assets at risk. One of the objectives under this goal is to provide regular updates to the Very High FHSZ maps. Another objective under this goal is to update existing data for values and assets at risk utilizing GIS data layers and other mapping solutions.

California Building Code

To help manage wildfire risk at the state level, the California Building Code (CBC) contains standards for building materials, systems, and or assemblies used in the exterior design and construction of new buildings. For example, the 2016 CBC establishes minimum standards for the protection of life and property by increasing the ability of a building located in any FHSZ within SRA or any Wildland-Urban Interface Fire Area to resist the intrusion of flames or burning embers projected by a vegetation fire. (A Wildland-Urban Interface Fire Area is a geographical area identified by the state as a FHSZ, or other areas designated by the local agency to be at a significant risk from wildfires.)

However, the 2016 CBC standards have limitations. The standards only apply if: 1) the building site is located on land designated as a FHSZ or as a Wildland Interface Fire Area; and 2) the application for the building permit was submitted on or after July 1, 2008. Therefore, these standards do not apply to structures located outside of these designated areas. Additionally, these standards do not apply to structures for which building permit applications were submitted prior to July 1, 2008, regardless of their designation.

Local-level Responsibilities

Local agencies are responsible for identifying and managing wildfire risk within their jurisdictions. Cities and counties have multiple tools at their disposal to reduce wildfire risk, such as the General Plan, zoning ordinance, California Government Code, local fire departments, and Hazard Mitigation Plans. With new levels of concern regarding wildfires, local jurisdictions can evaluate their General Plans and zoning ordinances to locate weaknesses and bolster mitigation strategies related to wildfire hazards. Local jurisdictions can also create overlay zoning or overlay districts for areas prone to wildfires that mandate heightened development regulations and landscape wildfire mitigation compliance measures.

Local jurisdictions may rely on the support of regional agencies, such as the Association of Bay Area Governments (ABAG), which runs the Resilience Program to support local governments in planning for wildfires and other natural hazards. ABAG’s Mitigation and Adaptation Plans project supports the ongoing development of hazard mitigation and climate adaptation plans at the local level.

In addition, local government agencies receive guidance from State agencies, such as CAL FIRE and the State Board of Forestry and Fire Protection. The local government agencies can then implement recommendations through the enactment of ordinances. However, it is ultimately the responsibility of the local agencies to identify and manage wildfire risk within their jurisdictions.

Individual-level Responsibilities

In order to reduce risks associated with wildland fires at the individual level, California Government Code Section 51182 identifies specific strategies to be undertaken by a person who owns or leases an occupied dwelling or structures in, upon, or adjoining a mountainous area, forest-covered land, brush-covered land, or land within a Very High FHSZ. Strategies include maintaining defensible space around the structure, removing dead portions of trees near structures, and maintaining the roof clear of leaves, needles, or other vegetative materials. As stated in the California Government Code, local agencies having jurisdiction over the property can provide oversight to ensure that these mitigation strategies are implemented.

Conclusion

Wildland fire is a natural part of California’s landscape. The responsibility for identifying and managing wildfire risk in California is shared by the State, local jurisdictions, and individual property owners.

As a starting point, areas of significant fire hazards must be accurately mapped, routinely updated and property owners informed of risks. Local jurisdiction must impose restrictions through their land use regulations and long-range planning efforts to ensure that high risk areas are protected. Individual property owners must maintain defensible space, remove dead portions of trees, and keep roofs clear of vegetative materials.

Moving forward, dialogues will continue to take place within communities to identify wildfire-related risks and propose actions to reduce these threats. These discussions will propel local communities towards their own solutions to prepare for and reduce wildfire-related risks.

References

2016 California Building Code, Part 2, Volume 1, Chapter 7A – Materials and Construction Methods for Exterior Wildfire Exposure, https://codes.iccsafe.org/public/chapter/content/9997/, Accessed October 24, 2017.

CAL FIRE, California Fire Hazard Severity Zones Maps, http://calfire.ca.gov/fire_prevention/fire_prevention_wildland_zones_maps, Accessed October 23, 2017.

CAL FIRE, FRAP Projects, Fire Probability for Carbon Accounting, http://frap.fire.ca.gov/projects/fireprobability, Accessed February 9, 2018.

CAL FIRE, Incident Information, Large Fires 2017, http://www.fire.ca.gov/index, Accessed February 9, 2018.

CAL FIRE, Incident Information, Number of Fires and Acres, http://cdfdata.fire.ca.gov/incidents/incidents_stats?year=2017, Accessed February 9, 2018.

CAL FIRE, Wildland Hazard/Building Codes, http://calfire.ca.gov/fire_protection/fire_protection_wildland, Accessed October 24, 2017.

California Department of Forestry and Fire Protection, California’s Fire Hazard Severity Zones, http://osfm.fire.ca.gov/codedevelopment/pdf/Wildfire%20Protection/FHSZ%202007%20fact%20sheet.pdf, Accessed October 24, 2017.

Headwaters Economics, Land Use Planning to Reduce Wildfire Risk: Lessons from Five Western Cities, January 2016, https://headwaterseconomics.org/wildfire/solutions/lessons-five-cities/, Accessed November 13, 2017.

State Board of Forestry and Fire Protection, 2010 Strategic Fire Plan for California, Revised April 2016, http://bofdata.fire.ca.gov/hot_topics_resources/fireplanrevison_final_04_06_16.pdf, Accessed October 24, 2017.