Community Wildfire Threats

This chapter describes ways that naturally-occurring and human-set wildfires affect people and communities in forested and rangeland areas.

Associated Indicators


Acres of new projected Wildland-Urban Interface development, by proximate FHSZ class (high density housing adjacent to areas of intact wildland fuels)

Provides a measure of the risk to new dense Interface development (<1 house/2 acres) of wildfire penetration, based on its proximate Fire Hazard Severity Zone (FHSZ) class. In contrast to Intermix areas, Interface lands have more manicured, irrigated and highly modified vegetation, and it is often the structural fuels can contribute significantly to fire spread. Wildfires in this form of WUI fires are relatively rare, and typically only spread under very extreme fire weather conditions. But due the high density of assets such as homes, roads, and residential and commercial infrastructure, damage levels from burning can be very high even over small areas.

Acres of older high-risk WU Interface projected to be replaced by new more fire resilient WU Interface, by Fire Hazard Severity Zone class

Projected new, more fire-resilient development that would replace existing historically high risk WUI. Current WUI that has both high adjacent fire threats, and characteristics that create high susceptibility to fire damage (e.g. vegetation density and structure, ignition-prone building materials, poor design and lower fire protection capacity) can have its risk level reduced by replacing the adjacent wildland fuels with high density Interface. The new Interface would provide both a spatial buffer to wildland fire threats, and would also be less fire-prone, due to current design standards and improved community planning requirements associated with new development.

Acres of projected new Wildland-Urban Intermix development, by FHSZ class (low density housing embedded within intact wildland  fuels)

Acres of projected future Intermix by Fire Hazard Severity Zone (FHSZ) class. Intermix is defined as between 1 house/2 acres, and 1 house/20 acres (0.5 to 0.05 houses/acre). Landscapes with housing densities of less than 1 house per 2 acres ( 0.5 houses/acre) typically retain most of their natural vegetation fuels, and consequently are not as resilient to wildfires as denser urbanized areas. Although wildfires are fairly frequent in these types of environments, structural values (due to low housing density) are typically relatively low (as compared to urban areas).

Cost of structures exposed

In residential areas near or within forests and shrublands, structures may be destroyed or damaged by wildfires that naturally occur, or that are caused by human activity. Structures will vary in how resilient or resistant to fire they are (e.g., because of roof or siding material). The replacement or repair costs may be borne by homeowners or by insurers and represent a cost to society of having structures mixed in with vegetation where fires are likely to occur.

Cost of structures lost

Wildfires can cause damage or loss of structures near or within naturally-vegetated areas. The replacement or repair cost for these structures may be borne by the homeowner, or by insurers. It represents an actual cost to society of wildfire effects on structures built in areas where wildfire occur.

Cost of suppression

Most fires that occur where structures or people are present are actively suppressed. The cost for material and personnel to suppress fires is borne by responsible local, state, or federal entities.

Forest fuel conditions and trends related to wildfire risks

This indicator will provide information in both tabular and map form on forest fuel conditions and progress in managing forest fuel conditions. Both the public and policy makers want to know where and the how much of the state's forests are in a condition that is resilient to catastrophic wildfires and, over time, is the condition improving or worsening.

Number of Communities at Risk (CAR) that are also Firewise Communities

Shows where specific efforts are being taken by identified at-risk communities to reduce the chances for loss and damage from wildfire. Communities at Risk (CAR) participating in the Firewise Communities USA/Recognition Program develop an action plan to guide residential risk reduction activities, and encourage their neighbors to participate as well. Firewise communities must invest at least $2 per capita in local Firewise actions each year and conduct a “Firewise Day” community event. Communities on the CAR list which are recognized as Firewise Communities may be more prepared and/or resilient in the face of wildfires.

Number of Communities at Risk (CAR) with a Community Wildfire Protection Plan (CWPP)

This shows which designated Communities at Risk have made specific planning efforts to reduce their chances for loss and damage from wildfires. A list of communities at high risk of structure damage from wildfires was first created by the National Fire Plan, to identify priority projects designed to reduce the fire risks to communities. This Communities at Risk (CAR) list was initially limited to communities neighboring federal lands, but was since expanded to include all high-risk communities identified within the wildland-Urban Interface. A number of these communities have prepared a CWPP - a collaborative strategic plan, developed by the community or neighborhood together with relevant agencies, to reduce its risk of losses from vegetation fires by managing hazardous fuels and structure vulnerability. These communities are likely to be more prepared and/or resilient in the face of wildfires. In addition, communities with a CWPP will be given priority for funding of hazardous fuels reduction projects carried out under the auspices of the federal Healthy Forest Restoration Act.