Kaldor Fire last year and the community he’s been hit hard by, Grizzly Flats, have been in the news recently. The most recent is an article that aired on CBS’ 60 Minutes yesterday (see video below) About the fire southwest of Lake Tahoe, California. On August 16, Radio Cap wrote about a fuel processing program the US Forest Service planned to run across the city, but it has just barely begun. Then on September 26 and 27, NPR published articles about the failed project and the difficulties in setting up scheduled fires.
The 13-minute-at-60-minute segment focused on the initial attack of the fire, which was first reported around 7 p.m. on August 14. One of the first challenges was access, complicated by a cliff road and another unreachable one. maintained. According to the dispatch log, the incident commander ordered everyone to put out the fire at 1:42 a.m., about seven hours after it broke out. The reason cited in the record was “accountability”. 60 Minutes said the Forest Service told them it was for the safety of the firefighters. Later in the second day, according to 60 Minutes, “the agency rejected six CAL FIRE engines and crews, letting most go before their replacements arrived.”
As you can see on the map below, about 29 hours after the fire started, 781 acres were identified. After another 44 hours, it burned into the Grizzly Flats, growing to more than 55,000 acres.
I strongly believe in an aggressive initial attack “using overwhelming force using both ground and air resources, arriving within the first 10-30 minutes when possible”. But it’s hard to criticize the accident commander’s decision, especially a year later, to take everyone out of the fire due to safety concerns. Obviously, the burning conditions were in favor of the fire that first night, not the firefighters. In 44 hours it grew from 781 to 53,465 acres while spotting more than a mile according to map data from infrared planes.
If the Forest Service has completed the massive fuel processing project they promised around Grizzly Flats, that doesn’t automatically mean that no building in the community will be destroyed. Would the cure have been a mile away, reducing the number of burning embers landing in the city? Mostly not. It only takes one person – to land in a leafy gutter, on a roof, on wooden steps, in a vent, or on dead wood or grass near a structure and the house can be destroyed. When one house ignites, it becomes another anthrax generator, flooding the rest of the community with sources of ignition, causing the fire to grow exponentially.
In September of 2021, Jack Cohen and Dave Strohmayer wrote about main ignition area On Wildfire Today:
“Surprisingly, research has shown that ignition in the home during severe wildfires is caused by local conditions in the home. The ignition weaknesses of the home in relation to nearby burning materials within 100 feet essentially determine the home ignition. This area of the home and its immediate surroundings is called the ignition zone. (HIZ).Typically, high burning embers start igniting within the HIZ—directly to homes and nearby flammable items that lead into homes.Although severe wildfires can raise a fire more than half a mile to start a fire, local conditions The tiny embers where smoldering embers land and build up determines the ignition. Importantly, most home destruction during severe wildfires occurs hours after intense bushfires stop near the community; residential fuels—homes, other structures, and plants—continue to spread the fire within the community” .