USA — Fighting fire from the air is one of the most expensive costs fire agencies accrue when battling a wildfire.
The aerial attacks in the Rim Fire alone cost taxpayers nearly $11 million, $8 million for the aircraft and another $3 million for the retardant.
The U.S. Forest Service is now trying to determine actually how effective is dropping water and retardant from the air.
“When the planes come over it’s just like you won the Super Bowl or something. It’s exciting to see those huge DC-10’s, I believe, coming so low and dumping all that retardant,” said Groveland resident Chris Loh.
Nobody can convince Loh that the air attack on the Rim Fire didn’t save his family’s property, his business and his town.
Loh and his family own Spinning Wheel Guest Ranch, surrounded by trees blackened from the Rim Fire, which roared through in the late summer of 2013.
“In a way, we kinda knew it would happen. Of course, when you first get word it’s the most devastating thing you can think of,” Loh said.
Loh’s family is trying to replant and rebuild, but he is forever grateful for the price paid to to save his part of the world.
“I know that we have a great fire service out here. The firefighters who came and worked on this fire were stellar. They are number one,” Loh said.
But the aerial attack was one of the most expensive aspects of the $95 million effort to put out the blaze.
“It’s a huge cost. It can go up as high as you want and keep on sending aircraft,” said Bill Stewart, a former Cal Fire firefighter who now researches fire management at UC Berkeley.
Stewart questions whether air drops are used more than they should be used.
“When the fires are really hot, sometimes they are not effective. The flames are going up so the (water and retardant) never gets on the fires,” Stewart said.
Stewart said the air attacks are often referred to within the ranks as “CNN drops,” because they look good on TV, and the general public expects them.
“It helps some, and if you didn’t do it, people would say, ‘Why didn’t you call it in?” Stewart said.
Stewart says sometimes the money would be better spent on hand crews and bulldozers.
“I always asked, ‘What’s the cost-effectiveness of these drops?’ and they said, no one has ever tried to look at it,” Stewart said.
The forest service has tested the chemicals that make up the retardant at the agency’s laboratories in Missoula, Montana.
Researchers there check whether the mix of pink fluid slows down a bed of shredded aspen. They also test to see how corrosive new mixtures are and whether aircraft are able to coat the ground, according to the forest service’s standards.
USFS scientist Shirley Zylstra showed how materials coated in the retardant burn slower putting off more smoke than a similar bed without any retardant.
“Even in this short of distance, you can see how it decreased the intensity and the fire was moving much slower through this bed than through our untreated bed,” Zylstra said.
But Zylstra says testing retardant in a controlled setting isn’t the same as dropping it on trees or in the mountains.
“If you ask any firefighter, they are going to tell you there are times when you know it did what they expected it to do and what they needed it to do. You can ask that same firefighter, have you ever used retardant when it didn’t work, and they will say, absolutely. It just depends on so many things,” Zylstra said.
Ryan Baker is a forest service researcher in Southern California looking specifically at how aerial attacks work in real fires.
“There certainly have been cases where aerial firefighting has not been as effective as desired,” Baker said. “Those situations, those cases, are good case studies for understanding what needs to be improved in the system.
Baker and a team of firefighters are collecting data to look at when water and retardant drops worked and when they didn’t.
Baker said no two situations are the same, which means there’s not always a right answer.
“The type of fuels we have and the conditions, the heat and humidity that affect the way fires burn in different areas of the country,” Baker said.
Aerial firefighting is inherently dangerous. One study looking at air attacks found more than half of all wildland firefighters killed in the line of duty between 2000 and 2012 were in air accidents.
Just last year, a 62 year-old pilot for Cal Fire was killed in Yosemite.
“They are undertaking a risky mission and so we have to balance the people in the aircraft with the benefit that we are trying to do,” said Chris Schow, fire chief for the Stanislaus National Forest. He was one of several commanders overseeing the Rim Fire.
“That tactical use of our aircraft and how they do support our firefighters is well thought out and well planned and we don’t, we don’t take it lightly,” Schow said.
Baker is hoping with new computer models eventually a fire chief could plug in a fire’s location and the conditions and a computer could accurately help assist them in their decisions whether to send in planes or ground crews, and where to put them to get a fire under control.
Baker said he guesses firefighters have 95 percent of that information already.
“The research that’s going on now, ideally, could get us to 99 percent,” he said. “But we’re talking nature, and nature is always unpredictable.”
Baker said it will take several years of data before that research is expected to be complete.
The research is one thing, but from Loh’s perspective the aerial attack was essential.
“We would have lost a lot more. We would have lost a lot more structures, we would have lost a lot more houses and possibly we would have lost the whole community,” Loh said.