Assessing the impacts of federal forest planning on wildfire risk-mitigation in the Pacific Northwest, USA

We analyzed the impact of amenity and biodiversity protection as mandated in national forest plans on the implementation of hazardous fuel reduction treatments aimed at protecting the wildland urban interface (WUI) and restoring fire resilient forests. We used simulation modeling to delineate areas on national forests that can potentially transmit fires to adjacent WUI. We then intersected these areas with national forest planning maps to determine where mechanical treatments are allowed for restoration and fire protection, versus areas where they are prohibited. We found that a large proportion of the national forest lands (79%) can spawn fires that burn adjacent WUIs. The bulk of the predicted WUI exposure originated from simulated fires ignited outside of conservation and preservation reserves and in dry forests, rather than moist mixed conifer forests. Thus the notion that fuel buildup in reserves on national forests contributes to wildfire risk in the urban interface was only partially supported by the data for the region studied. Most of the national forest lands that contribute wildfires to the WUI are not within the boundaries of community wildfire protection plans, which may undermine the effectiveness of these planning efforts. We used the spatial data themes developed in the study to map conflicts and opportunities for restoration and mitigation of WUI wildfire risk. The analysis disentangles the spatial complexity of managing landscapes for multiple socio-ecological objectives as part of ongoing restoration programs, collaborative planning, and national forest plan revisions on national forests in the US.