Del Mar, Calif., is known for its beautiful beaches and appealing downtown, yet inland are dry stretches of scenic canyons dotted with multimillion dollar hillside homes. The canyons are as picturesque as are the homes; the problem is that the canyons are a fire hazard headache for the Del Mar Fire Department.
The department determined that if a forest fire fueled by a hot, dry Santa Ana wind struck the Del Mar canyons, it could torch certain areas in a matter of minutes, especially since the canyons have narrow roads that can hamper firefighters in reaching fires quickly. And with homes interspersed throughout the hills, evacuation from a severe forest fire would be difficult and dangerous.
That's why the Del Mar Fire Department turned to urban foresters to beef up its firefighting repertoire. Urban foresters use software and fieldwork to identify high-risk areas with overgrown vegetation or narrow buffer zones, and develop plans for reducing these fire hazards, giving firefighters additional time and buffer zones to combat fires.
Understanding All Components
One of the significant fire hazard areas identified by the Del Mar Fire Department was the Crest Canyon area. The department determined that more than 60 homes could burn in less than 15 minutes if a large fire swept through the area -- quicker than it would take firefighters to reach the houses along the narrow dirt roads.
"In Crest Canyon, with houses intermixed with heavy vegetation, there is a really significant fire hazard, especially because there are very narrow roads so it causes more issues for firefighters," said David Ott, Del Mar and Solana Beach fire chief. "There is the possibility for a fire to want to continue to burn through the entire area."
To mitigate the high risk of a disastrous fire, Ott looked for help from Dudek, an engineering and environmental consulting corporation that helps solve regulatory issues for municipal agencies and major landowners. With a $140,000 grant from the Federal Emergency Management Agency, Ott hired Dudek's urban foresters to help reduce fire hazard in the Del Mar canyons.
Like standard foresters, urban foresters work for government and private industries to manage and protect forests in urban environments ranging from cities to the rural landscapes often just a couple miles from suburbia. Part arborist, forest planner and fire prevention expert, urban foresters have to understand all components of an urban forest, including knowledge of plants and their ecosystems, soil, water and wildlife, as well as knowing the dynamics of forest fires and fire prevention.
Dudek's urban foresters set out to the hills of Del Mar with GIS and recorded the types of vegetation, the density, weight and volumes of dried brush -- or "fire fuel" -- the topography of the areas including the direction of landscapes in relation to the sun, temperatures and weather.
All the information was compiled into field assessments and fire behavior modeling maps with BehavePlus and FlamMap software. Using complex algorithms and logarithms, the software created fire-modeling maps that predict fire behavior characteristics in the event of a wildfire, including the rate a fire would spread and flame height. The programs factor in potential conditions such as the moisture in fire fuel and wind speeds.
The result is a vegetation management plan for Del Mar that targets specific areas for brush removal to mitigate fire exposure. Unlike Del Mar's previous broad prevention efforts, the new vegetation management plan used the field assessment maps to identify precisely where the fire department needed to reduce hazardous fuel volume to limit fire continuity, lower potential threats to property and provide buffer zones so firefighters can more effectively control the spread of fire.
"We developed a plan of interlacing the landscape with islands of fire fuel and learned