In 2017, the western U.S. experienced more than 50,000 wildfires, with extensive damage in Montana, Oregon, Utah, and Washington state and record-setting destruction in California in particular. Fire burned more than 1.3 million acres across the Golden State, resulting in unprecedented loss of life and damage to more than 10,000 structures.

The Natural Approach: Bioengineered Wildfire Mitigation

The Federal Emergency Management Agency (FEMA) has long focused on working with communities to reduce wildfire risk. Through our Hazard Mitigation Technical Assistance Project (HMTAP), we are developing educational material to assist both the general public and technical staff in identifying bioengineered wildfire mitigation measures to reduce the impact of these devastating events. The two-page fact sheet and in-depth supplemental guide address both pre-wildfire and post-wildfire options, including post-wildfire flood mitigation.

The documents inform readers that bioengineered wildfire mitigation involves using aspects of the natural environment to mitigate the risk of wildfire to the built environment. The application of these techniques varies according to geography, climate, elevation, and the building density and types of design within communities.

Mitigating the Risk of Wildfires

Pre-wildfire mitigation measures focus on the maintenance of defensible space and fire-focused landscaping, including:

  • Thinning of trees, vegetation, and brush, and removal of highly flammable vegetation
  • Disposal of debris, such as pine needles, leaves, and dead limbs
  • Maintenance of firewood and compost piles at least 30 feet from structures
  • Elimination of "fuel ladders," including shrubs near tree branches
  • Design of defensible spaces with fire breaks, such as driveways, walkways, patios, and fences
  • Integration of natural barriers such as rock outcroppings, wetlands, streams, ponds, and deciduous trees
  • Landscape plans that prioritize plants with high-moisture content
  • Avoidance of barks and wood mulches

Post-wildfire recovery and mitigation measures focus on landscape stabilization and forest regeneration and include:

  • Landscape stabilization for erosion control, soil stabilization, and flood control
  • Techniques to address soil moisture and break up charred (compacted) surface soil
  • Control of invasive pioneer plant and insect species
  • Planting of perennials suited for recovery
  • Large-scale seeding

These techniques offer a number of technical, economic, ecological, and social benefits. They can increase accessibility for emergency personnel and first responders; reduce landscaping, maintenance, and insurance costs; promote a diverse ecosystem and preserve healthy wildlife habitats; and promote community safety and resilience.

"We Made It Through One Disaster, Let's Prevent Another"

Another initiative sponsored by FEMA through our Customer Communications Contract with HWC, Inc., is the Flood-After-Fire Campaign, an outreach program focused on providing information to stakeholders in at-risk geographies. The campaign includes educational materials to raise awareness of the heightened risk of flooding after a fire.

The campaign targeted areas affected by the devastating wildfires in the western U.S. during the summer and fall of 2017. We conducted a multidimensional analysis to identify the key geographic areas for outreach - examining watershed characteristics and topography, and population center demographics such as income and languages.

Materials developed include a toolkit containing public service announcements, social media posts, infographics, and how-to guidance for engaging audiences. A webinar was held to announce and share the products with local officials, emergency responders, local non-profits, and other potential toolkit users.

Themes for the campaign included "We made it through one disaster, let's prevent another," "avoid the one-two punch of flood-after-fire," and "floods can move as fast as fires." The educational materials reviewed the increased risk of flooding after wildfires, explaining that because soils are less able to absorb water after a high-intensity fire, communities that have been impacted may be at greater risk for riverine and surface flooding, especially during rain and snowmelt seasons.

The Flood-After-Fire campaign followed an ambitious timeline, with materials timed for release to the regions during their active flood season. The rapid-response campaign was launched on the West Coast in December 2017 and continued this spring in the mountain states of Wyoming and Montana. A detailed evaluation and report on the campaign's effectiveness will be released in late 2018.