This is the second in a series of blog posts about smoke and wildfire.

As discussed in the first part of this series, wildfire smoke has serious harmful effects, and individuals and communities should aim to prevent exposure to smoke to the greatest extent possible. The most straightforward way to reduce potential exposure to wildfire smoke is to prevent wildfires from occurring and to suppress wildfires once they become dangerous. For that reason, wildland firefighting is an essential element of our response to the wildfire crisis, and the wildfire workforce should be supported. However, responding to fires through suppression alone isn’t enough to stop catastrophic wildfire; proactive stewardship is needed to adequately address the underlying problem by promoting forest health and resiliency. In this post, the second part of our series on wildfire smoke, we’ll go on to discuss the origins of the wildfire crisis and potential policy responses to reduce the harm caused by catastrophic wildfire.

How should we manage forests to reduce the risk of catastrophic wildfire?

In much of California and the West, an excessive focus on fire suppression has actually made the current wildfire problem more severe. Policies that aimed to prevent or suppress all wildland fires, including low-intensity natural fires and Native American cultural burning, caused many ecosystems which had evolved along with fire to be deprived of it for decades. This led to the unchecked growth and buildup of flammable vegetation in forested areas, which, along with hotter, drier weather, has contributed to an exponential increase in the intensity of wildfires.

To address these conditions, a new approach to forest management is needed. Rather than focusing overwhelmingly on fire suppression—a strategy which not only contributed to the current crisis but, as recent fires demonstrate, isn’t ultimately capable of preventing catastrophic fire—our approach to wildfire should focus on reducing the amount of hazardous flammable material in forested areas and promoting overall forest health. This approach would use a variety of landscape-level stewardship interventions, including prescribed fire and cultural burning (collectively referred to as “beneficial fire”) where safe and feasible.

While it may seem strange to call for the use of fire as a way to mitigate wildfire, forest science and the events of the last several decades show that regular intervals of low-intensity fire are ultimately better for forest health and public safety than a policy of attempted complete suppression which leads to catastrophic wildfire. However, even beneficial fire comes with costs and risks to nearby communities, including the risk of smoke exposure. Going forward, our approach to fire should aim to promote forest health and resiliency, maximize the benefits of beneficial fire, suppress catastrophic wildfire, and limit the public’s exposure to smoke.

How should the government regulate wildfire smoke?

Because wildfire itself can’t and shouldn’t be completely suppressed, smoke from wildfire can’t be completely eliminated. However, because wildfire smoke includes pollutants like PM_2.5, which are dangerous in any amount, limiting exposure to smoke to the greatest extent possible is critical for public health. Recognizing both of these realities—first, that human exposure to smoke should be limited as much as possible, and second, that a certain amount of fire is not only unavoidable but beneficial—is necessary to address the wildfire crisis. The government’s current approach to smoke has room to improve on both of these issues.

First, although PM_2.5 is designated as a pollutant under the Clean Air Act (CAA), the standards the Environmental Protection Agency (EPA) has currently set for atmospheric levels of PM_2.5 are not strict enough to reflect the adverse health effects of PM_2.5 exposure, especially when it comes to vulnerable populations and communities facing intersecting climate and pollution threats.¹ To that end, environmental health and justice advocates have called for a stricter standard that requires lower atmospheric PM_2.5 levels.

Second, although forestry and land management agencies have increasingly recognized the necessity of fire and the beneficial effects of low-intensity fires such as prescribed fire and cultural burning, the legal framework for these intentional fires is extremely restrictive. Land managers seeking to use prescribed fire and Native Americans seeking to conduct cultural burns must obtain a variety of permits and approvals, including air quality permits. The expense and administrative burden created by this process limits these groups’ ability to use beneficial fire.² Although permitting is an important tool to protect air quality, placing such a high burden on tribes and land managers threatens to make the system counterproductive: by preventing low-intensity beneficial fires, it increases the intensity of catastrophic wildfires, which emit far more pollution.

The EPA has the opportunity to address both of these issues through its ongoing rulemaking process to update its PM_2.5 standards. As CEPP argued in a comment authored by two students in our practicum, the EPA should protect public health by tightening PM_2.5 standards, but do so in a way that keeps a pathway open for the use of prescribed fires and cultural burns. As the modeling in the comment shows, if the PM_2.5 standard is tightened, California would not be able to meet its targets for the expanded use of beneficial fire while complying with the CAA, because the smoke released by beneficial fire would risk causing downwind areas across much of the state to exceed the standard. This outcome would make it not just burdensome but impossible to obtain permits for beneficial fire, threatening the viability of forest health projects.

The EPA has attempted to address this concern by endorsing an interpretation of the CAA which would allow the EPA to make a determination after the fact that—as long as it complied with other requirements—a beneficial fire didn’t legally contribute to a violation of CAA air quality standards, even if it caused downwind PM_2.5 levels to exceed the standard. However, because potentially violating the CAA without an up-front approval is risky for land managers responsible for fire, and because it has been possible so far to conduct prescribed fire without exceeding the standard, this interpretation has not been applied in practice.

Whatever approach the EPA takes going forward, it should tighten PM_2.5 standards in order to protect public health and vulnerable populations. In coordination with that goal, it should create a more dependable path to compliance for beneficial fire practitioners, in order to promote forest health and ultimately reduce the PM_2.5 pollution emitted by catastrophic wildfire.

Eric Macomber joined the Climate and Energy Policy Program and Stanford Law School as a Wildfire Legal Fellow in September 2022. His work focuses on law and policy issues relating to wildfire and the wildland-urban interface.

This post was originally shared on the Climate and Energy Policy Program‘s Substack.