Title
Report Regarding an Ordinance to Adopt the Updated California Fire Hazard Severity Zone (FHSZ) Maps for the City of South San Francisco (Ian Hardage, Fire Marshal)
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RECOMMENDATION
Recommendation
Introduce by title and waive further reading of an ordinance adopting the updated California Fire Hazard Severity Zone (FHSZ) maps for Local Responsibility Areas (LRAs) within the City of South San Francisco, as required by the California Department of Forestry and Fire Protection (CAL FIRE) (Ian Hardage, Fire Marshal).
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BACKGROUND/DISCUSSION
The California Department of Forestry and Fire Protection (CAL FIRE) is statutorily responsible for identifying and mapping areas within the state based on their level of wildfire risk. Pursuant to Public Resources Code Sections 4201-4204, CAL FIRE develops and maintains Fire Hazard Severity Zone (FHSZ) maps for State Responsibility Areas (SRAs) and, in coordination with local agencies, for Local Responsibility Areas (LRAs).
FHSZ maps are land use planning documents that reflect a “hazard” classification with respect to wildfire including two key elements:
• Probability of an Area Burning
• Expected Fire Behavior under Extreme Fuel and Weather Conditions
Lands within the FHSZs are classified in one of four categories: Very High (Shown in Red), High (Shown in Orange), Moderate (Shown in Yellow), and No Hazard (Shown in White). From these categories, the maps can be used to:
• Designate where California's Defensible Space Standards and WUI Building Codes are Required
• Trigger Real Estate Disclosure Documentation
• Inform a Municipality's General Plan for Development
The original FHSZ mapping process began in the late 1980s, focusing on slope, fuel load, fire weather, and historical wildfire data. These maps help determine where Wildland-Urban Interface (WUI) building standards, defensible space regulations, and real estate disclosure requirements apply. Over the years, California has experienced increasingly destructive wildfires due to climate change, longer fire seasons, and growing development into the wildland-urban interface. As a result, CAL FIRE undertook a major update to the FHSZ maps beginning in 2022, applying modern fire science and advanced modeling to reassess statewide wildfire risk. The updated SRA maps were finalized in late 2023, and local jurisdictions are now required to review and adopt updated FHSZ maps for their respective LRAs.
The City of South San Francisco is designated as a Local Responsibility Area under CAL FIRE’s jurisdiction. CAL FIRE has provided updated LRA Fire Hazard Severity Zone maps that identify areas within the City as Moderate fire hazard severity zones. The updated maps reflect the improved predictive models used by the state and were provided to the City on February 24, 2025.
Prior to the 2023 map updates, directed by Assembly Bill 211, FHSZ maps within the LRA only displayed areas within the Very High category. This did not mean other categories did not exist, just that they were not reflected on the maps. With the current version, all categories of severity zones are displayed and require some level of action by the local jurisdiction, based on severity level. With the release of the 2023 maps, South San Francisco now has areas designated as FHSZs. The City’s exposure is limited to roughly 1000 structures spread between the Westborough, Sunshine Gardens, and Terrabay Neighborhoods, and are shown in Attachment 1. These structures were given a FHSZ category of Medium and require no additional action outside of the City formally adopting the entire FHSZ map for South San Francisco.
State law prohibits a jurisdiction from reducing a FHSZ classification. It does allow for both the expansion of a current classification or an increase in classification based on a significant finding of fact. Fire Department staff have reviewed the maps and do not recommend expansion or increase in classification for FHSZs within South San Francisco. Fire Department staff did adjust current FHSZ classifications to align with property boundaries. This was done to reduce future confusion as the State’s map accuracy excluded portions of some parcels. Any portion of a parcel that is included in the FHSZ classification determines the entire parcel’s FHSZ classification.
CAL FIRE requires the City to formally adopt the updated LRA FHSZ maps via ordinance after providing an opportunity for public comment. Staff has reviewed the proposed maps and coordinated with CAL FIRE and city staff to ensure procedural alignment and accuracy. The attached ordinance fulfills these requirements and initiates the process of local adoption. Upon final adoption, the maps will be transmitted to CAL FIRE for certification and public dissemination.
The adoption of the updated FHSZ maps represents a critical component of the City’s wildfire mitigation, community risk reduction, and resilience planning efforts. The ordinance before the Council tonight marks the first step in formalizing local adoption of CAL FIRE’s revised maps.
PUBLIC OUTREACH
Fire Department staff made the FHSZ maps publicly available on the City’s website on March 10, 2025, including an email address for public comment (fhsz.ssf@ssf.net). Property owners within affected areas were notified of proposed changes and provided opportunities to review the updated maps online. Properties within the affected areas were also notified via United States Mail of the maps and were invited to a public meeting reviewing the maps and their impacts.
FISCAL IMPACT
There is no direct fiscal impact to the City from adoption of the updated maps.
ENVIRONMENTAL DETERMINATION
The proposed action is exempt from the California Environmental Quality Act (CEQA) pursuant to CEQA Guidelines Section 15308, as it is an action taken by a regulatory agency to protect the environment.
CONCLUSION
Staff recommends that the City Council introduce by title and waive further reading of an ordinance adopting the updated California Fire Hazard Severity Zone (FHSZ) maps for Local Responsibility Areas (LRAs) within the City of South San Francisco, as required by the California Department of Forestry and Fire Protection (CAL FIRE).
ATTACHMENTS
• Ordinance - Adoption of Fire Hazard Severity Zone Maps for LRA
• CAL FIRE Final LRA Fire Hazard Severity Zone Map