The Forest Service has posted its 2013 aerial fire retardant statistics. Over 12 million gallons dropped, a 50% increase over last decade’s average annual amount (page 220 of the Forest Service’s aerial retardant FEIS summarizes use for the 2000-2010 decade).
As usual, Region 5 (California) led the nation, accounting for over 7 million gallons. And the Stanislaus NF led Region 5 with over 2 million gallons dumped. Ahh, the good old Rim Fire, of course.
So what did retardant accomplish at the Rim Fire?
Obviously, retardant didn’t achieve the initial attack objective of keeping the fire below 300 acres in size. But not for lack of effort. As one informed commentator pointed out over at wildfiretoday.com “over 32,000 gallons of retardant were applied between detection (approx 1540) and dark on the first day, 65,000+ the second day and (largely due to visibility issues) 23,000 the third day.” Within 20 minutes of first detection the incident commander had decided that the steep, dry, remote canyon was too dangerous to insert boots on the ground (“CALFIRE helitack pilots refused to insert crews at the origin for lack of safety zones”), without which retardant is largely ineffective. With that sensible decision to put firefighter safety first, it’s a head scratcher why the retardant air attack continued.
But, continue it did. Not just during the next three days, but as “the fire grew, literally, exponentially for 6 days. That’s doubling in size every day. 55,000 acre runs.” Did retardant use slow that doubling, stop those runs? Of course not. The prevailing winds blew the fire across the Stanislaus, into Yosemite, until the fire ran out of fuel on barren granite hard surface of the Sierra mountains.
Question for readers. How would the Rim Fire’s outcome been different had retardant not been used?