In this month’s blog, CWI’s research fellow Andrew Johnson explores the efficacy of wildfire fuel breaks, from the perspective of both a researcher and a practitioner with years of experience on fire crews in California. This blend of practical knowledge and measured academic assessment makes for a unique perspective, particularly as we work to amplify the conversations happening at the intersection of policy, practice and academia. 

There are tens of thousands of miles of fuel breaks in the western United States and plans to build many more. These linear fuel treatments are primarily constructed to reduce fire risk by mitigating fire behavior, and ultimately giving firefighters somewhere to stop a fire’s spread.

That is the idea, at least.

In practice, they are typically effective less than half of the time, which has been established in multiple scientific articles, and yet we continue to build them. Maybe our definition of effective is too narrow, or maybe we have some cultural attachment to these treatments that transcends common sense. Either way, the former deserves to be investigated.

Personal experience has shown me that fuel breaks can be effective in multiple ways. Having spent the better part of the last decade rotating between life as a student and working on some sort of fire crew, I’ve seen fire behavior and how fire acts when it hits a break. When working with fire, you use every opportunity to get the fire to do what you want. Usually this means slowing it down, getting it to stop burning so intensely or getting it to stay put. Typically, these opportunities present themselves with some sort of fuel type transition, or change in vegetation type/density, which is the result of natural features or manmade actions; think a streambed, wash, bald ridge, roads, rocks and powerline right-of-ways.

I’ve taken part in firing operations using these features, and I’ve watched aircraft increase retardant effectiveness along them as well. I’ve staged in them and I’ve watched a crew member take refuge in a spot fire’s footprint on a grassy ridge while a crown fire raged around him. This isn’t nearly an exhaustive list of the ways that I’ve seen fuel type transitions used to manipulate fire behavior —and how those manipulations can be used to increase the effectiveness of a variety of different management tactics—but they’re some of the notable ones.

The experiences of firefighters using natural and man-made fuel breaks and the propensity for agencies responsible for fire management to keep building them—agencies run by people whose fire experience vastly overshadows my own—may be evidence for some that these controversial control features are worth constructing. Unfortunately, the scientific review just isn’t there, at least not to the level it needs to be. This has been the foundational problem statement behind my research while pursuing a PhD at the University of California, Berkeley. I have been privileged to work on a project that was funded by the Joint Fire Science Program, where we surveyed fire managers about perceived fuel break effectiveness, juxtaposing that with the textbook definition of fuel break effectiveness. Beyond this juxtaposition, we investigated how fuel breaks have increased the effectiveness of a variety of fire management tactics, such as the implementation of firing operations, use as safety zones, and increasing time for evacuations. I am also examining how fuel break configurations decrease fire risk in fire modeling scenarios and how landscape level (non-linear) fuel treatments were used during suppression operations on the Caldor Fire.

In that light, work that looks at how management decisions impact risk to firefighters and increase the effectiveness of their operations is vital. It is up to managers to weigh the importance of such benefits against the potential ecological downsides. It is up to researchers to understand manager needs and the changing world in which they work so that they have the tools they need to make the best decisions.

I have to note that research like mine exists amongst an entire field examining the ecological implications of various fuel treatments. However, it is a concern that some may find this work to exist in opposition to, and not as a compliment to, such work. Especially in light of the understudied ecological effects of linear fuel breaks in brush ecosystems, where they can disrupt habitat continuity, introduce invasive species, and provide access to negligent recreators. All of these are valid concerns, but all we can do as researchers is provide managers with information to assess the tradeoffs inherent in deciding how to manage their (or our) land. In that light, work that looks at how management decisions impact risk to firefighters and increase the effectiveness of their operations is vital. It is up to managers to weigh the importance of such benefits against the potential ecological downsides. It is up to researchers to understand manager needs and the changing world in which they work so that they have the tools they need to make the best decisions. It is my hope that my work exists somewhere in the realm of the useful, giving managers another reference point when deciding which tool to use to manage their land, dependent on their goals.

Written By Andrew Johnson

Research Fellow, CWI; PhD Candidate, UC Berkeley

Andrew is a PhD candidate at the University of California, Berkeley in the department of Environmental Science, Policy, and Management where he is advised by Professors Brandon Collins and Scott Stephens. He has been working with wildfire in different capacities since 2014, often splitting years between firefighting and being a student. Andrew seeks to combine his wildland fire field experience with an interest in research to answer questions about how we manage wildfires. His time spent on the fireline showed him that an untapped source of information in the wildland fire environment was the expertise of his coworkers and supervisors.