Chaparral fires burned seventy-nine thousand hectares of land in six Southern California counties, killed several people, and damaged eleven hundred homes and other buildings, most of them in Malibu.
Fires began at the Southern California urban-wildland interface on October 26, 1993, and burned for nearly two weeks across an area that stretched from the Mexican border to the northern fringes of Los Angeles. By the end of October, fourteen major conflagrations had destroyed 731 homes and razed 66,800 hectares in Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura counties. By mid-November, losses had exceeded $1 billion.
The nine major Southern California fires that broke out in early November, 1993, killed 3 people and injured 111, displaced more than 30,000 residents, and destroyed 1,084 homes. The worst conflagration was in Malibu, where the deaths and many of the injuries occurred, 350 homes were destroyed, and damages were valued at $375 million. The Malibu disaster
Malibu was founded as a ranch in 1804 and developed after 1938 as a center of surfing and home to wealthy people connected with the entertainment industry. The city of Malibu merges with a corridor of Los Angeles suburbs in which the number of inhabitants tripled over the three decades before the 1993 disaster. During that period, no major fires were recorded in the area, although they remained an ever-present risk.
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The progress of the fire was hastened, and its path was made very irregular, by Santa Ana winds gusting erratically at more than 55 miles per hour. A high-pressure cell had developed north of Malibu, and a low-pressure cell had developed to the city’s south. These conditions generated strong air flows that warmed up as they descended down the mountains to the coast. Consequently, on arrival at Malibu the winds were hot, dry, and strong, and so they remained until the weather system began to migrate away late on November 3. Ambient temperatures during the period of the fire were 9 to 12 degrees Celsius at night and 26 to 31 degrees Celsius during the day.
Schools and factories, including the Hughes Aircraft Corporation laboratories in Malibu Canyon, were evacuated during the afternoon of November 2. House-to-house evacuation continued after nightfall, and in the early evening some luxury homes burned, after which the flames turned toward the campus of Pepperdine University. The university was eventually spared by a change in wind direction. Traffic on Pacific Coast Highway was at a standstill, and attempts by the police to move the traffic and cordon off the area were thwarted by residents who were anxious about the fire threat to their homes. In fact, more than one-half of the firefighters in the Emerald Bay area were used not to combat the flames but to rescue home owners who had refused to leave.
The authorities had received advance warning about extreme fire conditions, but they could do little to halt the progress of the conflagration. About seven thousand firefighters were deployed, some of whom came from as far away as Nevada and Oregon. Their strategy involved bulldozing firebreaks through the chaparral scrub and using Bell-412 helicopters, which could carry 370 gallons of water, and C-130 airplanes, which could haul 2,900 gallons of fire retardants. Overflights ceased at dusk, but helicopters were able to resume flying before dawn, and the aircraft took off again at first light. Fire-retarding foam was also sprayed at the base of the canyon slopes to inhibit the spread of the flames.
The fire lines were drawn at Tuna Canyon on the northern boundary of Malibu, the Pacific Coast Highway on its ocean side, and Topanga Canyon Boulevard to the south. The intensity and speed with which the blaze moved sent firefighters into retreat, and late on November 2 the first command post, located on Pacific Coast Highway, had to be abandoned and a new one organized further west at Pepperdine University. Many of the 250 fire engines at work in the area, as well as bulldozers and their crews, were assembled at the junction of Pacific Coast Highway and Topanga Canyon Boulevard, but they all had to retreat east as the fire spread relentlessly toward them. Meanwhile, in Tuna Canyon some ground crews were nearly overrun by the advancing flames. The Topanga Canyon Boulevard and Pacific Coast Highway lines were held for most of November 3, but sea breezes late in the day blew the fire across the line of fire trucks on the canyon road. Firefighters fought back, and the front was gradually contained, but not until the majority of buildings in Las Flores Canyon Creek had been destroyed.
Eventually, the Malibu fire killed three people, injured more than one hundred (seven of them seriously), burned 13,500 hectares, and damaged or destroyed 350 homes. The injured suffered variously from large-scale burns, smoke inhalation, and damage to the lungs caused by inhaling superheated air.
Ten days later, more than four centimeters of rain fell in only twenty-four hours, causing heavy erosion of the area damaged by the fires. In Malibu, mud flowed across Pacific Coast Highway, blocking three lanes during the morning rush hour. Mudflows also damaged homes that had escaped the flames.
In an election that took place on the day of the Malibu fire, Californians approved Proposition 172, which maintained the 0.5 percent sales tax used to finance public-safety measures. Two days later, Governor Pete Wilson hastily reversed his decision not to allow $1.8 million to be spent on two Canadian-built CL-215 “Super Scooper” aircraft capable of loading more than 1,500 gallons of water in twelve seconds. In the wake of the fires, the U.S. secretary of the interior, Bruce Babbitt, suggested that Californians should think seriously about whether it is wise to extend urbanization into dry chaparral lands.
A wildfire that is burning out of control endangers people, settlements, or resources. Such a fire is considered to be “confined” if it is limited to a predetermined area using natural or constructed barriers, “contained” if it is surrounded with a control line in order to stop its spreading, and “controlled” if the line around it is completed. If valuable resources must be protected, vigorous direct control is preferable, although policy should be reviewed daily in relation to weather conditions. The Malibu fire was first contained and then controlled as firefighters gradually succeeded in their work.
When the leaves and branches of trees burn, the result is a crown fire, which may depend on the flames at the surface or may run ahead as flames propagate through the vegetation canopy. Most chaparral conflagrations are dependent crown fires or surface fires, and they may give rise to ground fires if leaf litter is deep enough to burn thoroughly and if backburns consume areas that have already been warmed by fire. If winds are high or great drafts are caused by atmospheric heating, then spot fires may break out when burning brands are lobbed into dry material ahead of the main front. The Malibu blaze was predominantly a fast surface fire, with elements of the running crown fire, peripheral spot fires, and periods of backburn. Chaparral fires of this kind tend to be very hot, with maximum temperatures of 540 to 1,100 degrees Celsius, as the fuel consists of highly flammable woody grasses and dry, oleose shrubs. Convection and radiation may stimulate the fire to burn uphill, but chaparral fires are often conditioned by overall wind direction and speed, although irregularities of topography and fuel load tend to cause their spreading fronts to become uneven.
A few large conflagrations are responsible for much of the land burned in California. Thus, in the northern part of the state, 1 percent of fires burn 96 percent of area affected. There, where forests predominate, population densities are low and many of fires are caused by lightning. In contrast, most of the three thousand fires each year in Southern California are started by human activity, and many of them are larger than natural fires would be. Although one fire in 1993 was caused when the fierce Santa Ana winds made power lines arc, the Malibu blaze and most others were believed to have been set deliberately. Arson is usually a compulsive trait, and those who indulge in it often have deep-rooted but concealed psychological ailments. In the United States, less than 20 percent of arsonists are ever caught.
Fire risk is greatest at the urban-wildland interface, which is where more than seven million Californians live and where some of the highest rates of population increase are evident in the state. In Berkeley in 1923, fire destroyed 584 homes; in Santa Barbara, fire destroyed 234 houses in 1977 and 641 in 1990. The tunnel fire of October, 1991, in the hills above Oakland and Berkeley killed 25 people and destroyed 2,810 homes in one of the fiercest conflagrations that suburban California has known. Hot, dry Santa Ana winds spread the flames over 728 hectares in only ten hours. Such events are exceptionally expensive; hence, damage by California brushfires amounts to more than $100 million per year and firefighting costs average $50 million per year.
The October, 1993, fires had particularly severe impacts on rare birds and their habitats. Fires depleted the U.S. population of gnatcatchers by 330 pairs (15 percent), and about 460 pairs of cactus wrens, or 15 to 20 percent of the U.S. population, died. Interior Secretary Bruce Babbitt had proposed that the Endangered Species Act be used to induce developers to create scientifically defined nature preserves, and in Orange County the largest private landowner, the Irvine Company, had earmarked land to conserve, but 1,500 hectares of it were burned in 1993. Earlier in the year, Stanford wildlife biologist Dennis Murphy had argued that no more than 5 percent of Southern California coastal sage scrub could be developed without permanently hurting the chances of recovery of endangered species. Instead, the fires burned such large areas and left such fragmentary habitat that the survival of the remaining birds was called into question.
There was a clear relationship between the Malibu fire and increased rates of erosion. Elimination of chaparral vegetation can increase the rate of dry particle-by-particle gravitational sliding, or dry ravel. When it rains copiously, denuded watersheds can generate networks of rills and gullies or mudflows. Although studies have shown that fire in chaparral is ten times more frequent than debris flows, burning at temperatures of 175 to 200 degrees Celsius may distill organic chemicals until hydrophobic residues make the soil impermeable, allowing even more runoff, gullies, and mudflows to develop.
Devastating fires in 1970 and 1977 led to the formation of California Firescope,
Surveys conducted in 1976 in Southern California revealed that 74 percent of respondents thought that naturally ignited forest fires should not be allowed to burn, even in the absence of a threat to life or property (although more than one-half agreed that the occasional forest fire could refresh the land). By the 1980’s, 80 percent of respondents supported prescribed burning. Surveys of Southern California residents in 1983 revealed growth of awareness of forest-fire hazard; many residents, however, had done nothing to minimize potential fire losses.
Nevertheless, particular events have stimulated improved preparedness. Inadequate hoses caused the water supply to fail during the 1991 Berkeley fire, and narrow, winding roads hampered the evacuation of residents and the arrival of emergency services. Inadequate communications and poor liaison led the Oakland emergency services to miss a Forest Service red alert; after the disaster Oakland purchased a mobile infrared sensor. The city cleared the vegetation on some hillsides, widened some of its roads, and updated the local building codes. When some sixteen thousand properties were inspected two years later, however, one-fourth lacked the mandatory spark arrestors on chimneys or were surrounded by flammable vegetation.
The 1991 Oakland fires did, however, generate enough public awareness to induce the state of California to legislate in favor of fire-resistant roofing standards and the clearance of flammable material from home lots. In the three years before that legislation came into effect, the level of mitigation varied considerably from place to place. In 1992, a fire damaged or destroyed 636 structures in Shasta County, but residents were allowed to rebuild on the same heavily forested land. Other areas responded to fires by tightening their building requirements. For housing, this often involved fire-safe roofs, enclosed eaves, double-glazed windows, spark-arresting chimneys, and fire-resistant exterior cladding. For subdivisions, firebreaks, widened and straightened access roads, and more hydrants were required. The effects were clearly illustrated by the results of a fire in the Chino Hills, where twelve precode buildings were destroyed and two hundred postcode homes came through relatively unscathed. Rebuilding sometimes takes place so quickly, however, that legislation and the upgrading of municipal capabilities cannot keep pace with it.
The answer to steeply rising disaster losses appears to be insurance. Increasing numbers of California properties are being covered under the California Fair Plan, by which the industry reinsures itself and thus shares the burden of high risk. The insurance industry, however, offers few incentives to reduce the risk of fire damage, and some federal agencies are even less concerned. Researchers have concluded that generous disaster loans and reimbursements in effect subsidize and even reward home owners who rebuild without mitigating the risk of fire damage.
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Barker, Rocky. Scorched Earth: How the Fires of Yellowstone Changed America. Washington, D.C.: Island Press, 2005. An environmental reporter discusses the history of fire management policy in general, with a focus on Yellowstone National Park. Includes map, bibliography, and index. -
Barro, S. C., and S. G. Conrad. “Fire Effects on California Chaparral Systems: An Overview.” Environment International 17 (1991): 135-149. Provides a thorough and comprehensive survey of the ecological effects of chaparral fires. -
Cortner, Hanna J., Philip D. Gardner, and Jonathan G. Taylor. “Fire Hazard at the Urban-Wildland Interface: What the Public Expects.” Environmental Management 14 (1990): 57-62. Presents the results of surveys of how the public perceives the wildfire hazard. -
McPhee, John A. The Control of Nature. New York: Farrar, Straus and Giroux, 1988. Provides a readable introduction to a range of natural hazards and human vulnerabilities in the Los Angeles basin. Addresses wildfire and its consequences in terms of mudflows and erosion. -
Pyne, Steven J., Patricia L. Andrews, and Richard D. Laven. Introduction to Wildland Fire. 2d ed. New York: John Wiley & Sons, 1996. Definitive work on fire processes, firefighting techniques, and environmental fire management in the United States. Includes maps, bibliographic references, and index. -
Wakimoto, Ronald H. “National Fire Management Policy.” Journal of Forestry 88 (October, 1990): 22-26. Discusses policies, issues, and approaches to firefighting in the wake of the 1988 Yellowstone forest fires.
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