Air-Fouling Smoke Continues across California; 2009 Report Warned of Potential Fire Disaster

Smoke from the catastrophic Camp Fire continues to plague much of central and northern California, bringing dangerously high levels of fine particulate pollution (PM_2.5, particles less than 2.5 microns or 0.0001 inch in diameter). Hourly levels of PM_2.5 were in the red “Unhealthy” range at more than 30 official EPA monitors across the region Thursday morning, with seven stations reporting purple “Very Unhealthy” conditions.

Two stations near the Camp Fire recorded PM_2.5 levels on Thursday morning well into the maroon “hazardous” range—the highest level of danger on EPA’s Air Quality Index (AQI) scale. At this level, EPA warns that “this would trigger a health warnings of emergency conditions." Chico had PM_2.5 levels at a suffocating 333 μg/m³ for several hours on Thursday morning, which is nearly ten times higher than the 24-hour PM_2.5 standard of 35 μg/m³. The Woolsey fire near Los Angeles was mostly blowing out to sea, and thus air quality in Southern California was generally acceptable.

Light winds are expected over most of California’s smoke-affected areas through Saturday, keeping the air pollution levels dangerously high. On Sunday, a developing upper-level low pressure system will drive more of an onshore flow of air from the ocean, which may cause a modest reduction in the smoke. True relief from the smoke, however, will likely not occur until Wednesday or Thursday next week, when a major Pacific storm system is expected to move into California, potentially bringing the state its first significant rain of November.

Figure 1. The Air Quality Index (AQI) from wildfire smoke for fine particulate pollution (PM2.5) was in the red “Unhealthy” range (AQI above 150) over much of California on Thursday morning. Seven stations near Sacramento reported purple “Very Unhealthy” (AQI above 200) conditions, and two stations near the Camp Fire reported maroon “Hazardous” conditions. Smoke from the fires extended northwards into western Oregon, where orange “Unhealthy for Sensitive Groups” conditions prevailed. Image credit: EPA.

A 2009 grand jury report highlighted the risk of fire catastrophe in the Paradise area

Even after improvements over the last decade, the warning and evacuation process in Paradise was outraced by the deadly Camp Fire. As of Thursday morning, the Camp Fire fire was 40 percent contained after having burned across 140,000 acres (219 square miles). The Camp Fire is the deadliest and most destructive fire in California history, with at least 56 fatalities and over 9000 structures destroyed. Update (9:30 pm EST Thursday): Cal Fire announced on Thursday evening that the Camp Fire has taken at least 63 lives and destroyed at least 11,862 structures. There are now 631 people unaccounted for, a major leap from previous numbers.

One of the biggest problems in evacuating the Paradise region is sheer geography. As NPR reporter Paige St. John put it, “The problem in Paradise is that you can't get out….Once they needed to move and you had an entire town that needed to get out all at once, the roads quickly turned into parking lots.”
 
Much of Paradise was built during a growth spurt in the 1960s and 1970s, when the city’s population tripled from about 8,000 to around 24,000. The most populous part of Butte County’s higher terrain includes Paradise (population around 26,000 as of 2008) and a set of smaller communities just to the north (total population about 18,000 as of 2008) that are known collectively as the Upper Ridge. A route called the Skyway connects the Upper Ridge to Paradise, then continues toward the Central Valley as a broad, four-lane divided highway. Many people used the Skyway as an escape route from the Camp Fire.

The multi-pronged wildfire risks of Paradise and surrounding areas were studied in 2009 by one of the grand juries that are routinely impaneled each year to investigate civil and criminal matters for Butte County. In 2008-09, the county’s grand jury looked into wildfire and safety considerations in response to devastating fires in June 2008 across the Sierra foothills that make up the northeast half of the county.
 
The 2008 blazes, including the Humboldt Fire, burned more than 93 square miles (59,500 acres) in Butte County and destroyed at least 74 homes in the Paradise area. The only fire-related fatality was a woman who died of a heart attack while trying to flee, although her home was not in an evacuation zone, according to SFGate.com.
 
In contrast to the Camp Fire, which moved into Paradise from the northeast, the Humboldt Fire approached town from the southwest.
 
“By some miracle, the Humboldt Fire Incident did not cross the West Branch of the Feather River,” the jury noted in its report. “Had this occurred, property damage could have been huge and thousands of lives could have been threatened in Paradise and the Upper Ridge.”

Figure 2. With the Camp Fire sweeping in from the northeast, residents of Paradise and the Upper Ridge area needed to evacuate toward the south and southwest (downhill toward the Central Valley). North of Paradise, the route known as the Skyway was the only major escape route. The Skyway becomes a divided four-lane highway south of Paradise. Three other roads lead south from Paradise, but all are more problematic for fire evacuations, as noted in the article. Image credit: Google Maps (background).

Highway evacuation options are limited in the Paradise region

Although hundreds of people successfully escaped the 2018 Camp Fire via the Skyway, some did not make it. Three other paved routes extend south from Paradise—Neal Road, Clark Road, and Pentz Road—but they are far less suited for escaping a wildfire. The 2008-09 jury noted that all three of these two-lane routes had narrow or absent shoulders, moderate to sharp curves, and fire hazards adjacent to the roadway (steep slopes and dense fire fuel). In the Upper Ridge area, Skyway is the only major evacuation route leading south from the foothills. The jury noted that current building requirements specify at least two exit roads from any developed area.
 
During the 2008 Humboldt Fire, the Skyway, Neal Road, and Clark Road had to be closed in that order, so all of the traffic evacuating through Paradise was forced onto Pentz Road, whose posted speed limit was 40 mph. “It took three hours for vehicles to travel from the intersection of Pentz Road and Skyway to Highway 70, a distance of about eleven miles,” the jury observed. “This is an effective speed of approximately 4 mph.” During the Camp Fire, the Pentz Road area was part of the first zone to be evacuated, at 8:03 am, about 90 minutes after the fire was first spotted.
 
Among the jury’s recommendations in 2009 were that the county work on creating emergency evacuation plans for all of its high-risk fire areas. Paradise did develop just such a plan, and the city tested it in June 2016. “We even took one of our peak morning hours and made the road a contraflow…so we could show our citizens how it was going to work,” Paradise mayor Jody Jones told NPR.

“What happened, though, is typically you are evacuating a zone or two or three zones. You're not evacuating an entire town all at the same time.”

Communications limited as fire swept toward Paradise

As the Camp Fire grew rapidly and spread toward Paradise and the Upper Ridge on Thursday morning, evacuation messages were reportedly sent to both land-line phones and cell phones through the county’s CODE RED mass notification system. However, it appears that officials sending the CODE RED messages and going door to door were hard pressed to keep up with the fire’s pace. Moreover, residents with cell phones had to have signed up in advance in order to receive the phone alerts. A state law passed in September will allow counties to automatically sign up residents whose cell-phone numbers are associated with utility bills.
 
“I wish we had opportunity to get more alerts out, more warning out,” said Sheriff Kory Honea in a community meeting on Monday night, as reported by the Bay Area News Group. “We try to use as many systems as we can… But in the heat of this, it was moving so fast, it was difficult to get that information out.”
 
The overarching Wireless Emergency Alert system (WEA) for cellphones was not employed in Butte County during the Camp Fire, reported the San Jose Mercury News. The WEA sends certain emergency messages such as tornado and flash flood warnings to newer cellphones as long as the phone owners have not opted out of the service. Some California counties have hesitated to use the WEA for fire evacuation out of concern it would serve as a blunt instrument, alerting too many citizens outside precise evacuation zones and causing traffic tie-ups. Sonoma County officials chose not to use the WEA during the catastrophic fires that struck in October 2017, including the Tubbs Fire—the state’s most destructive blaze on record prior to the Camp Fire. An August article in the Sacramento Bee explored some of the challenges around using the WEA for fires and other disasters.

Radar-derived rendering of #CampFire plume from ignition through devastation of #Paradise. Radar proving invaluable in understanding plume dynamics and fire progression. Maybe for issuing warning too? #CAfire #CAwx pic.twitter.com/cbjiCK9L67

— Neil Lareau (@nplareau) November 15, 2018

Another option not employed in the Camp Fire is a “fire weather warning," a seldom-used product that can be disseminated by the National Weather Service at the request of local officials. “Such a warning must be requested by someone outside of the National Weather Service, such as an emergency manager, rather than being initiated by Weather Service staff themselves,” Andrew Freedman noted in Axios. “That's the rule even if forecasters can see on Doppler radar or by looking out the window that a fire is headed for a populated area.”
 
The upshot is that many residents of Paradise apparently saw and heard little to nothing about the fires until the last minute. “We didn’t get a robo call, announcement or any notice from Cal Fire or city," one resident told the Mercury News. "We had to find out about it second-hand.”

Jeff Masters wrote the air-quality section of this post.