Discretion advised: This is a developing story involving missing persons.
More than 20 people are missing or unaccounted for after a significant flash flood tore through a remote section of Grand Canyon National Park on Saturday, August 29, destroying infrastructure throughout Bright Angel Canyon and prompting an urgent air evacuation effort, according to the National Park Service.
How the Flood Happened
Strong thunderstorms dropped roughly two-thirds of an inch to more than an inch of rain within 15 minutes to an hour, falling atop recently burned terrain in the area around 2:30 p.m. local time Saturday. The rainfall sent a slurry of mud and debris rushing through the canyon, with floodwaters rising more than 5 feet in just 10 minutes. The flood struck the Bright Angel Canyon and Phantom Ranch area, both popular destinations for hikers exploring the canyon floor.
Widespread Infrastructure Damage
The flooding destroyed nearly all the footbridges spanning Bright Angel Creek, eliminating hiker access across the creek and forcing the closure of one of the park's most difficult trails, the North Kaibab Trail. Metal debris and structural remnants entering the Colorado River led officials to shut down river traffic entirely due to the risk posed by floating wreckage. "The flash flood resulted in significant impacts to infrastructure throughout Bright Angel Canyon," the National Park Service said in a statement. "Grand Canyon National Park staff are continuing to assess damage to trails, bridges, utilities, facilities and other infrastructure."
Evacuations Underway
By Sunday morning, 62 people had been evacuated by air from Phantom Ranch and the lower North Kaibab Trail, carried out by the Arizona Department of Public Safety working alongside the National Park Service. Additional evacuations from Phantom Ranch and the Cottonwood Campground were planned for the following days. As of the latest reports, no injuries have been confirmed.
The Search for Missing Hikers and Campers
The National Park Service said Sunday it is working to account for anyone who may have been in the affected area at the time of the flood, with figures on those unaccounted for ranging from 15 to more than 20 across different official updates as the situation continues to develop. In a statement, the agency said: "Grand Canyon National Park staff, in coordination with the Arizona Department of Public Safety, are continuing evacuation and response efforts and working to account for individuals who may have been in the affected area."
Officials are specifically asking the public for information about anyone who may have been hiking or backpacking along Bright Angel Creek on August 29, as well as anyone with a campground reservation at Phantom Ranch or the Bright Angel Campground during that period. Anyone with relevant information is asked to contact the National Park Service Investigative Services Branch (ISB).
About Phantom Ranch
Phantom Ranch, near the bottom of the canyon, has been a coveted Grand Canyon destination since it opened in 1922, and is accessible only by hiking, raft, or mule transport — meaning anyone caught in the flood zone would have had limited options for a quick escape given the area's remoteness and difficult terrain.
Ongoing Flood Risk
A flash flood watch remained in effect for the Grand Canyon through Monday, as forecasters warned of continued dangerous downpours across Arizona and Utah. The National Weather Service described the flash flood risk as minor to moderate for Sunday and Monday around Grand Canyon National Park, and officials warned the area could face additional thunderstorms and heavy rainfall that could trigger further flash flooding, debris flow, and rockfall. Two helicopters from the Park Service and Arizona's Department of Public Safety searched the North Kaibab Trail corridor and the Colorado River from the mouth of Bright Angel Creek to the Deer Creek Narrows on Sunday morning as part of ongoing search efforts.
Why This Happened Now
The flood's severity was likely intensified by the fact that the rainfall fell atop recently burned areas, which tend to shed water and debris far more rapidly than intact vegetation and soil, dramatically increasing flash flood risk during heavy rain events — a well-documented pattern following wildfires in canyon and mountain terrain across the American Southwest.
What's Next
With search and evacuation operations ongoing and additional storms possible through Monday, officials say the number of people confirmed accounted for is likely to continue shifting as response efforts proceed in the challenging, remote canyon terrain. For continuing live updates, see the NBC News report.