PHOENIX (CN) — Firefighters in two Arizona counties continue to battle three major wildfires raging across the state Monday.
The Contreras Fire burning in southern Arizona’s Pima County has expanded to over 20,360 acres. The blaze, 53 miles southwest of Tucson, started June 11 on a remote ridge of the Baboquivari Mountain range on the Tohono O'odham Nation Reservation.
The current conditions prompted officials with the Pima County Sheriff's Office to warn residents of Hayhook Ranch Estates and the Indigenous community of Pan Tak to prepare to flee if it becomes necessary..
“Residents should consider voluntarily relocating outside the affected area with family [or] friends,” the sheriff's office said in a statement. “Grab your emergency go kit. Keep in mind unique needs for your family or special equipment for pets and livestock.”
Kitt Peak National Observatory, home to one of the largest collections of astronomical telescopes in the Northern Hemisphere, lost four buildings this past week because of the fire.
According to the Eastern Area Incident Management Team, a residential building, a dormitory and two outbuildings were destroyed. The team also confirmed damage to scientific buildings appears to be nonexistent.
“Observatory staff will be doing [an] in-depth assessment of each of the structures,” said Mary Woods, a public information officer with the EAIMT. “They do not anticipate that the heat from the fire [was] hot enough to do any kind of damage.”
Fire crews took active defensive steps Monday to protect the observatory. The fire is only 40% contained.
In northern Arizona near Flagstaff, officials have fought to contain two fires.
The Pipeline Fire, 15 miles north of downtown Flagstaff has blackened 26,528 acres. Containment stands at 50%.
According to the U.S. Forest Service, the fire started June 12 and is approaching a semblance of stability. The agency's current plan of action is to assess the effects of the precipitation received over the weekend.
Nearly a quarter inch of rain fell Saturday on some affected areas. Additional rain in the forecast should bring some relief to the region.
Luke McGuire, a geomorphology professor at the University of Arizona, told Courthouse News that the risks of runoff and flooding are high after wildfires.
"Fire reduces the ability of soil to infiltrate water and removes plant litter from the soil surface that would normally help to store water during rainstorms,” McGuire said. “The net result is that more rainfall turns into runoff in recently burned areas, which can lead to flooding in areas downstream of the burn scar."
McGuire also warned of debris flows in the event of heavy runoff.
"Fires like the Pipeline Fire that burn over steep terrain can also increase the potential for debris flows,” he said. “Debris flows are slurries of water, mud and boulders that form when runoff rapidly erodes soil as it moves down steep slopes."
East of the Pipeline Fire, the Haywood Fire has so far charred 5,575 acres of land since it sparked June 13. Containment stands at 40%.
The fire is now burning well within the Kachina Peaks Wilderness, an area within the Coconino National Forest that contains Arizona's tallest mountain, Humphreys Peak. The wilderness has a minimal recorded fire history. According to the U.S. Forest Service, years of persistent drought have left much of northern Arizona with dry pine, grass and brush, all primed to fuel a fire.
The priority for fire crews is to limit the perimeter expansion. According to Coconino County officials, Saturday's rainfall had minimal to somewhat significant effect depending on the area.
But Michael A. Crimmins, a climatologist at the University of Arizona, is optimistic the fires will subside soon.
“The monsoon moisture is working its way up and into the Southwest a bit ahead of schedule,” Crimmins said. “I think this is a turning point for the fire season in Arizona this year. The long-term drought, dry winter, recent heat and wind have all contributed to the rapid spread of the Pipeline and Tunnel fires. The increasing humidity and rainfall should help [firefighters] gain the upper hand on these fires. More fires with lightning starts will still be a threat for the next couple of weeks, until we can really soak the whole region. Still looking good for monsoon precipitation to continue across Arizona over this period though.”
Saturday marked the 20th anniversary of the Rodeo-Chediski wildfire, which burned 460,182 acres of northern Arizona and caused catastrophic damage. The human-caused blaze cost the state $43 million to put out and destroyed 491 structures.
The fire was the worst in Arizona history until 2011’s Wallow Fire, which burned 538,049 acres.
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