Firefighters have learned to depend on stands of fire-resistant scrub oak and sumac in low-lying areas to naturally slow brush fires that rage out of control in San Diego County canyons and backcountry.
Last winter, though, much of the sumac and scrub oak in East County was killed by hard freezes. Those plants are now dry and brittle--brown tinder, more flammable than the manzanita and buckwheat that normally fuel the fires.
A combination of these elements, area fire officials say, may produce one of the worst summers on record for brush fires.
This year, when a brush fire tears over a ridge and hits a ravine filled with sumac and scrub oak, instead of slowing the fire, the freeze-dried vegetation is apt to explode, showering the air with flaming leaves that can cause the fire to leapfrog ahead.
"Comparatively, we're similar to 1985, which was the worst year we've had for loss of property," said Tom Kelly, the San Diego area division chief for the California Department of Forestry. "We're really in a drought cycle."
The conditions that can lead to runaway brush fires are actually worse this year than when excessive rainfall produces more vegetation that dies and provides fuel for summer fires, Kelly said.
What rainfall San Diego received this season fell before Jan. 1. But dormant brush doesn't "accept" rainfall until after Jan. 1. The brush grew only one inch rather than the normal five inches, Kelly said. It died quickly, immediately drying out.
"It's an earlier fire season," Kelly said. "The brush (already is burning) a lot sooner than we expect it to burn. It's going to be hot and flashy and explosive. Normally, you don't see those conditions until September or October. They're already here now."
Reacting to such conditions, the Forestry Department hired 95 additional seasonal firefighters and brought in an air tanker for fighting fires a month earlier than usual. "May 4 was the start of the fire season for us," Kelly said.
Conditions Similar to 1985
The conditions for canyon brush fires within the City of San Diego are precisely those that led to the devastating 1985 Normal Heights fire, city officials say. That arson-started blaze, San Diego's most destructive, destroyed 64 homes and damaged 20 others along the southern rim of Mission Valley. It raged for eight hours before 400 firefighters from as far away as Riverside County controlled the inferno. Miraculously, although thousands were forced to flee, no one was killed or seriously injured.
"You're never really prepared for something like Normal Heights," said city Fire Marshal Jim Sewell. "We're prepared for almost anything . . . almost any emergency that can come up." But no particular precautions have been taken by city fire crews in light of this year's high potential for brush fires, Sewell said. Fire engines "are within six minutes of almost every area in the city," he said. "That's our standard."
Fire prevention measures were taken after the Normal Heights fire, however. The Fire Department identified 18,000 canyon-rim parcels as high fire risk areas. Twelve thousand privately owned canyon-rim lots were inspected for brush control under a city program begun last year. The new regulations require that owners of canyon-rim homes remove all brush and trees within 30 feet of their homes and trim vegetation to a height of 18 inches for the next 70 feet.
About 9,000 houses were found to be in compliance upon first inspection. About 1,500 of the remainder were in compliance by the time they received the notice of violation. Those not in compliance may be taken to court for violating the city's fire hazard ordinance.
The city also has contracted for brush clearing on 620 acres of public "open space" in canyons.
Although money has been approved to remove the brush from 330 of those acres, it is uncertain whether the remaining 290 acres will be funded.
The two programs were not recommended for refunding this year, according to Deputy City Manager Jack McGrory.
"There is $19.3 million of unfunded needs that we could not put into the budget," he said. "They point out the overall financial problem we have this year."
A public hearing on the open space brush removal program is scheduled for 5:30 p.m. Monday at City Hall. The private canyon-rim lot inspection program will be discussed at a 6 p.m. public hearing Wednesday at City Hall.