Land use planning and wildfire: development policies influence future probability of housing loss, Syphard et al. 2013

Wildfire is a challenge that threatens human settlement at an increasing scale, but planning and development does not always address this threat. In fact, policy around land use is in large part responsible for the destruction of homes and property and the threat to human life that occurs in wildland-urban interfaces (WUIs). While there is much literature on how to suppress fires, mitigate their damage, or manage for less destructive fire seasons, a more far-reaching strategy would be to stop building in fire prone areas. Land use decisions can be improved to lessen the risk of infrastructure loss and foster healthy ecosystem function.

Land use planning is an alternative that represents a further shift in thinking, beyond the preparation of communities to withstand an inevitable fire, to preventing new residential structures from being exposed to fire in the first place. The reason homes are vulnerable to fires at the wildland-urban interface is a function of its very definition: “where homes meet or intermingle with wildland vegetation”. In other words, the location and pattern of homes influence their fire risk, and past land-use decision-making has allowed homes to be constructed in highly flammable areas. [Syphard 2013: 1-2]

In many areas, including in California, we have come to expect fire, but have not necessarily learned to live with it. The authors of this study analyzed what types of human development carried out in the next several years might contribute to or avert the risk of fire damage. They examined the South Coast Ecoregion of San Diego County, which they describe as:

topographically diverse with high levels of biodiversity, and urban development has been the primary cause of natural habitat loss and species extinction. Owing to the Mediterranean climate, with mild, wet winters and long summer droughts, the native shrublands dominating the landscape are extremely fire-prone [Syphard et al. 2013: 2].

This study acknowledges the responsibility humans have in shaping the landscape and its biodiversity, and in contributing to fire activity by building into wild areas and expanding WUI. They sought to understand how patterns of development and housing density might influence future fire spread and intensity. They found that

structures in areas with low- to intermediate- housing density were most likely to burn, potentially due to intermingling with wildland vegetation or difficulty of firefighter access. Fire frequency also tends to be highest at low to intermediate housing density, at least in regions where humans are the primary cause of ignitions [Syphard 2013: 2].

Though it is impossible to reverse the effects of policies that have shaped the fire landscape we have today, understanding the way human behavior contributes to our own risk of harm from wildfire can help us plan intelligently going forward. The authors conclude that

With projections of substantial global change in climate and human development, we recommend that land use planning should be considered as an important component to fire risk management, potentially to become as successful as the prevention of building on flood plains. History has shown us that preventing fires is impossible in areas where large wildfires are a natural ecological process. As Roger Kennedy put it, “the problem isn’t fires; the problem is people in the wrong places [Syphard 2013: 10-11].