Simulating effects of land use policies on extent of the wildland urban interface and wildfire risk in Flathead County, Montana

This study used a wildfire loss simulation model to evaluate how different land use policies are likely to influence wildfire risk in the wildland urban interface (WUI) for Flathead County, Montana. The model accounts for the complex socio-ecological interactions among climate change, economic growth, land use change and policy, homeowner mitigations, and forest treatments in Flathead County's WUI over the five 10-year subperiods comprising the future evaluation period (i.e., 2010–2059). Wildfire risk, defined as expected residential losses from wildfire [E(RLW)], depends on the number of residential properties on parcels, the probability that parcels burn, the probability of wildfire losses to residential structures on properties given the parcels on which those properties are located burn, the average percentage of wildfire-related losses in aesthetic values of residential properties, and the total value (structures plus land) of residential properties. E(RLW) for the five subperiods is simulated for 2010 (referred to as the current), moderately restrictive, and highly restrictive land use policy scenarios, a moderate economic growth scenario and the A2 greenhouse gas emissions scenario. Results demonstrate that increasingly restrictive land use policy for Flathead County significantly reduces the amount and footprint of future residential development in the WUI. In addition, shifting from the current to a moderately restrictive land use policy for Flathead County significantly reduces wildfire risk for the WUI, but shifting from the current to a highly restrictive land use policy does not significantly reduce wildfire risk in the WUI. Both the methods and results of the study can help land and wildfire managers to better manage future wildfire risk and identify residential areas having potentially high wildfire risk.