New hope for wildfire prevention

Almost by accident, two Stanford University engineers have discovered a new way to prevent wildfires — a kind of prophylactic gel that could potentially last all season.

Announced Sept. 30 at the National Academy of Sciences Proceedings, the technique uses an environmentally safe, gel-like fluid which helps fire retardants sprayed on vegetation last a lot longer.

According to a Stanford news release, the new technology would not only prevent a “significant percentage” of wildfires, it would also “drastically reduce” the cost of fighting them — both throughout peak fire season.

“This has the potential to make wildland firefighting much more proactive, rather than reactive,” said Eric Appel, the study’s senior author and an assistant professor at the Stanford School of Engineering who developed the gel with Ph.D student Anthony Yu.

Wildfires are a natural and critical part of ecosystems such as ours, but that doesn’t include the human-caused variety. Hotter, drier weather has also intensified the destructive power of wildfires and lengthened fire season in the Inland Northwest. While we got relatively lucky in the 2019 season, in recent years the West has endured record-breaking fires. Across the country, federal firefighting costs in 2018 came to more than $3 billion — the highest ever. And that doesn’t include the many billions of dollars in damage done by fires each year.

In addition to active forest management, including treating and removing unhealthy trees, and clearing and burning potential fuels to help prevent them, wildfire management has generally been focused on fire suppressants and retardants (with suppressants often used as short-term retardants). When fighting active fires, crews use suppressants such as gels that carry water and superabsorbent polymers, like those in diapers.

These gels are frequently used as short-term retardants on buildings in the path of encroaching fires. The problem is they lose effectiveness once the water entrapped in them evaporates — often less than an hour during normal wildland fire conditions.

The Stanford-developed technology, a cellulose-based, gel-like fluid, stays on target vegetation through wind, rain and other environmental exposure.

Appel’s previous work was focused on human disease, developing gels which carry medicines in the body. According to Wired.com, Appel’s brother-in-law, a former fire prevention forester, inspired the idea of using similar gels to carry fire retardants. Developing a new kind of gel, the Stanford team worked with the California Department of Forestry and Fire Protection (CalFire) to test it on the types of vegetation where fire frequently starts.

What resulted was complete fire protection, even after half an inch of rainfall. The researchers are now working with the California Department of Transportation and CalFire to test the material on high-risk roadside areas that are the origin of dozens of wildfires in that state each year.

The researchers say the new gel could be applied with standard agricultural spraying equipment or from aircraft. While it washes away slowly and can last months, it does eventually degrade.

For more information see Woods.Standford.edu.

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Sholeh Patrick is a columnist for the Hagadone News Network. Contact her at [email protected].