The Southern Wildfire Risk Assessment
by Zoë Hoyle
The South consistently has the highest number of wildfires per year. Population growth is pushing housing developments further into natural and forested areas where most of these wildfires occur. —Fire in the South 2
The South is one of the fastest growing regions in the Nation, with an estimated population growth of 1.5 million people per year. With more than 88 million acres classified as wildland-urban interface, the South consistently has the highest number of wildfires per year. Across the region, more than 5 million acres are at high risk for fire, and 118,083 communities at risk of wildfire damage. Of these, more than 50,000 communities are at high to very high risk. It doesn’t help that the South has a year-round fire season, unlike other areas such as the West where wildfires are mostly seasonal.
The above are a few of the key findings reported in Fire in the South 2, published in December 2008 by the Southern Group of State Foresters (SGSF), a nonprofit organization consisting of State Foresters from each of the 13 Southern states.
Authored by Annie Hermansen- Báez, technology transfer coordinator for the SRS Integrating Human and Natural Systems unit and Anne Andreu, former University of Florida research associate, the publication reports the main findings of the Southern Wildfire Risk Assessment (SWRA), a comprehensive and uniform wildfire risk assessment for the Southern states sponsored by SGSF in collaboration with the Forest Service and four other Federal agencies. When it was started in 2003, the main objectives of the SWRA were to identify areas most likely to have wildfires and those most susceptible to wildfire damage, prioritize fuel reduction treatment efforts, and help agencies work together to improve emergency response.
The SWRA team set out by analyzing key components of wildfire risk in the South, and in 2005 published Fire in the South 1, a comprehensive review describing cultural uses of fire in the region, landscape characteristics, and the impacts of fire on the forest economy. The report established a baseline for the larger SWRA project. The 2008 Fire in the South 2 explains the objectives of the risk assessment, presents key findings, and demonstrates through case studies its practical applications.
A Powerful New Tool
The SWRA is the first comprehensive regionwide fire risk assessment of its kind in the Nation. The Southern states and Federal agencies including the Forest Service pooled their resources in a huge data collection effort that, for the first time, mapped surface fuels consistently for each of the 13 Southern states. SGSF contracted with Sanborn, a company which offers Geographic Information Systems (GIS) mapping services, to develop a software framework for viewing, modeling, and creating wildfire risk assessment maps.
The SWRA consists of a series of GIS layers that can be used separately or in combination to produce graphic images of wildfire risk and occurrence. Data layers include fuels, wildfire history, and initial fire dispatch locations, as well as weather, topography, soils, land ownership, land use, and transportation infrastructure. The SWRA also enables managers to identify areas where fuels may need to be reduced through thinning, mowing, herbicide, or prescribed burning.
“Unlike other risk assessments that simply combine GIS layers, the risk assessment applies published fire science along with GIS modeling techniques and assigns numerical values to data inputs,” says David Frederick, SGSF fire representative. “Because outputs are based on numerical calculations, users can change inputs and rerun calculations to determine their impact on overall wildfire risk.”
Fuel models can be changed, for example, to look at how planned fuel treatments will affect wildfire risk in a specific area. Structures such as new developments can be added to maps, as well as additional firefighting resources. The risk assessment can then be run again to show the effect such changes will have on overall wildfire risk.
Planners and managers at various levels—state, Federal, and local—are using the SWRA to support both planning and protection efforts. The system gives fire prevention specialists access to maps that show communities at risk, historical fire occurrence, and fire potential, allowing them to target at-risk communities with mitigation strategies. When a fire actually breaks out, incident commanders can generate maps to help decide where to deploy firefighting resources first, the best way to reach the location of a fire, and the optimal locations to deploy ground- and air-based equipment.
The assessment can also be used to raise public awareness about fire and fire management issues in the South, to increase support for wildfire protection planning, and to help prioritize areas in need of community wildfire protection plans, which help communities to identify strategic sites and methods to reduce risk for wildfire damage, and get funding for fuel treatments from the National Fire Plan.
“Wildfire risk is not simply the risk of an area burning, but also includes potential damage to roads, homes, and other assets of value,” says Hermansen-Báez. “Because the risk assessment process considered so many factors—from historical weather data to the current location of fire response dispatches—it can be readily used for planning wildfire protection.”
For more information:
Annie Hermansen-Báez at 352–376– 3271 or firstname.lastname@example.org
David Frederick at 334–590–6711 or email@example.com
The Southern Wildfire Risk Assessment project was funded by the National Fire Plan. Major Federal partners include the Forest Service, U.S. Fish and Wildlife Service, National Park Service, Bureau of Indian Affairs, and Department of Defense. Southern Group of State Foresters: www.southernforests.org
Andreu, A.; Hermansen-Báez, L.A. 2008. Fire in the South 2: the southern wildfire risk assessment. Atlanta: Southern Group of State Foresters. 32 p. Available online at: www.southernwildfirerisk.com/ reports/FireInTheSouth.html.
Frederick, D. 2008. High-tech risk assessment assists fire managers in the South. The Southern Perspective. November 12: 1–5. Available online at: www. southernforests.org/publications.htm.