ISO: Most Calif. Brushfire Destruction Occurred in Areas Deemed High-Risk by Satellite Mapping

October 5, 2004

With wildfires becoming a growing threat to homeowners and businesses in the western United States, insurers reportedly are increasingly relying on space age technology to help them identify these exposures as part of their underwriting and risk-management methodology.

ISO’s analytical study of Southern California wildfires reportedly shows a very high correlation between territorial risk factors identified by geographic information systems (GIS) and the devastation caused by the conflagrations that swept through dry woodlands last fall.

The ISO study analyzed property destroyed in the Cedar, Paradise and San Bernardino fires in late October and early November, which destroyed 3,300 buildings, burned down more than 425,000 acres of woodland and caused more than $2 billion in insured property losses.

By overlaying maps of its FireLine geographic information system on territories that were ravaged by California’s most severe brushfire, ISO experts were able to confirm that most of the destruction occurred in areas designated to be the greatest brushfire risk.

The FireLine maps, color-coded to indicate density of brushfire-causing fuel, when overlaid on satellite photos of the perimeters of the three fires, confirmed FireLine fuel classifications correlated accurately with the severity of property destruction.

The ISO study showed more than 96 percent of the areas burned by the wildfires were classified as containing significant brushfire fuel (dry grass, trees or dense brush). The study also showed more than 63 percent of the burned areas where thousands of homes were destroyed or damaged were classified as containing heavy fuel, presenting the greatest risk of wildfire.

The study further showed more than 95 percent of the homes and commercial properties destroyed by the fires were located in territories with high wildfire risk. Almost 40 percent of the dwellings destroyed were located in zones rated as the highest danger by FireLine.

“It is an unfortunate fact of life that some of the most desirable places to live, such as Southern California’s woodlands, also happen to be most prone to disasters, such as wildfires,” said Bill Raichle, assistant vice president, ISO Risk Decision Information. “But the availability of reliable GIS tools and other technology can accurately predict the degree of risk such woodlands pose. Information about high-risk wildfire zones helps consumers make informed decisions about where they choose to live and gives insurers a reliable tool to underwrite and price coverages for those homes.”

ISO’s FireLine is an automated solution for identifying potential wildfire hazards for any California address. By combining information on topography (slope of terrain), fuel types and road access for community firefighters, FireLine reportedly provides insurers a complete assessment of the locational risk of an individual property.

Insurers overlay FireLine satellite images of fuel, slope and access information on county and street maps to pinpoint wildfire hazards. Insurers may access FireLine components independently to develop their own hazard assessments.

FireLine is available on CD-ROM or via LOCATION, ISO’s new risk-assessment tool that provides risk-specific information representing every address in the United States in a simple database format. LOCATION provides ISO’s Public Protection Classification information on fire-mitigation capabilities of communities, along with information on crime, hurricanes, thunderstorms, earthquakes and California brushfires.

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