Modeling the Risk Reduction Benefit of Forest Management Using a Case Study in the Lake Tahoe Basin

Abstract

Across the United States, wildfire severity and frequency are increasing, placing many properties at risk of harm or destruction. We quantify and compare how different forest management strategies designed to increase forest resilience and health reduce the number of properties at risk from wildfire, focusing on the Lake Tahoe Basin of California and Nevada. We combine landscape change simulations (including climate change, wildfire, and management effects) with scenarios of current and plausible fuel treatment activities and parcel-scale fire risk analysis. Results suggest that more aggressive fuel treatment activities that treat more area on the landscape, whether through mechanical and hand thinning or prescribed fire, dramatically lower the fire probability in the region and lead to a corresponding lower risk of property loss. We estimate that relative to recent practices of focusing management in the wildland–urban interface, more active forest management can reduce property loss risk by 45%–76%, or approximately 2600–4900 properties. The majority of this risk reduction is for single family residences, which constitute most structures in the region. Further, we find that the highest risk reduction is obtained through strategies that treat a substantially greater area than is currently treated in the region and allows for selective wildfires to burn for resource objectives outside of the wildland–urban interface. These results highlight the importance of more active forest management as an effective tool in reducing the wildfire risk to capital assets in the region.