New Cal Fire map shrinks Berkeley’s ‘fire hazard’ zone. But what does that mean?

Cal Fire’s new hazard severity maps include new designations for local jurisdictions, moderate hazard (yellow) and high hazard (orange). The agency previously only listed very high hazard areas (red) for areas under local control. Credit: Cal Fire

State fire officials issued new fire hazard severity maps for the Bay Area Monday, and the section of Berkeley listed as “very high hazard” is less than half what it was when the map was first issued in 2011 — 454 acres, down from 1,269 — although much of that difference is made up for by new “high hazard” and “moderate hazard” zones.

Cal Fire previously mapped only “very high hazard” zones in areas under local fire jurisdiction. In Berkeley, there are now 202 acres rated as “high hazard” and 393 as “moderate hazard.” The new maps are still in draft form. 

While Berkeley and neighboring Oakland saw their overall hazard acreage significantly reduced — Oakland by nearly 35% — five other cities in Alameda County that previously had no hazard zones at all now show thousands of acres apiece at varying levels of peril, according to Cal Fire. Fremont alone, for example, had no very high hazard area under the 2011 map, and now has 9,121 acres at moderate hazard, 3,162 high hazard and 106 very high hazard.

Cal Fire previously projected much more of Berkeley as a “very high fire hazard” area. Credit: Cal Fire

California has heightened fire safety requirements for construction in high hazard and very high hazard zones, including what roofing and other materials builders can use. Berkeley is looking to go even further than the state, encouraging fire-safe upgrades on existing homes and other buildings in the city’s wildland-urban interface.

Cal Fire calculates fire hazards on a number of factors that change over time — fire history, existing and potential vegetative fuel, predicted flame length, how far embers can blow, terrain and weather, according to the agency. 

But what the state does not include, and which may account for Berkeley’s shrinking hazard area, are “a host of local conditions including structure type, age and structure separation distance, how much (if any) home hardening has occurred, nor the ability of the transportation infrastructure to support a rapid evacuation,” Berkeley Fire Department Chief David Sprague wrote in an email.

“As we have done for decades, staff is working to propose local amendments to the CAL FIRE maps that will expand the recommended hazard areas,” Sprague wrote. “This proposed expansion will take into account local conditions that Cal Fire does not consider.”

Berkeley maintains its own map of fire danger. Zone 1 (yellow), in the flats, has the lowest level. Zone 2 (orange), comprising most of the Berkeley Hills, is at higher danger on account of building density, proximity to wildland and other factors. Zone 3 (red), around Panoramic Way, has unique challenges related to access and evacuation. Credit: City of Berkeley

Berkeley has its own separate map of fire zones, more fine-tuned to account for building in the hills and other local factors. And while Cal Fire’s zones lay out where state law mandates homeowners must take certain safety precautions — creating a five-foot ember-resistant area around structures for instance — Berkeley’s own map lays out areas where the city has imposed its own fire-safe constraints on new construction, and includes more of the city’s eastern side.

The state is supposed to take local agencies’ recommendations into account and update the zone map. “I don’t believe the state ever integrated the local amendment into the state map in 2007,” Sprague said. “It’s caused confusion ever since.”

The Uplands and lower Claremont Hills, previously marked very high hazard, are no longer even listed as moderate hazard on the state maps. That neighborhood is a stone’s throw from the ignition site of the 1991 firestorm that killed 25 and obliterated entire sections of Oakland and Berkeley. It was that firestorm that prompted California to begin mapping fire hazards in local jurisdictions, where before it had only mapped hazards in areas under state control.

While home insurers take wildfire risk into account when determining whether or how to insure properties, they don’t generally use Cal Fire’s maps specifically, so “a change in designation on the maps for a single homeowner is unlikely to affect their insurance,” according to a Department of Insurance FAQ sheet on the new maps.

Cal Fire emphasizes its maps only project “hazard” and not “risk” — that is to say, the likelihood of a fire happening rather than the extent of the damage it might cause.

Homeowners and builders can look up city-specific parcel information on the city’s website, and information on state requirements is available through Cal Fire.

The Bay Area, coastal Northern California and some interior valley counties were part of the second phase of Cal Fire’s new fire zone rollout. The northeastern section of the state was the first phase; the central coast as far south as Ventura County and roughly the bottom half of the Central Valley will be the third phase, and southeastern California, along with Mono and Inyo counties, will be the fourth and final phase.