Community zones for assessing wildfire exposure in the United States

This community zones geodatabase delineates U.S. Census populated places in the Unites States (contiguous U.S., Alaska, Hawaii and Puerto Rico) and their associated wildland urban interface (WUI) as part of assessments to quantify wildfire transmission to communities. Research has shown that less than 20% of buildings in non-WUI areas are exposed to wildfire yet there are no community-level datasets that include the most vulnerable areas to wildfire, those areas where homes and structures are built among wildland vegetation. Local and regional risk planning processes, including engagement with communities, can use these boundaries to better define and map the scale of wildfire risk from large fire events and incorporate wildfire network and connectivity concepts into risk assessments.Community zones were created for the United States to pair U.S. Census populated places with wildland urban interface data (WUI) where homes and structures are built among wildland vegetation. This allows the assessment of community scale exposure while incorporating areas and buildings within them that are at the greatest exposure from wildfires and the source of many wildland ignitions. Research has shown that between only 10% and 20% of buildings in non-WUI areas are exposed to wildfire (Ager et al. 2021; Kramer et al. 2019), those areas typically defined by more “urban” community boundaries. And yet there are no community-level datasets that define the boundary of the community to include the areas where the majority of exposure and loss from wildfire are experienced. Current community wildfire protection planning (CWPP) guidelines are based on perimeters typically defined by administrative boundaries. The lack of a spatial planning framework for the CWPP process has led to a wide range of planning scales (e.g., neighborhoods, towns, multiple towns, entire counties) and associated boundary delineations that are potentially unrelated to the spatial extent of fire transmission to communities (Ager et al. 2018).