‘You could hear boulders moving’: Visitors describe Grand Canyon flash flood

Mike Sumaruk, from Tulsa, Oklahoma, spent months preparing for his first Rim-to-Rim hike in Grand Canyon National Park, a coveted feat for the rare visitor interested in dipping below the canyon’s surface. The trek is a rigorous one — including 5,000 feet of elevation gain over more than 20 miles — and while many hikers attempt the push in a single day, Sumaruk and a friend instead decided to break the journey up over a long weekend. 

Read more Preliminary magnitude 3.5 quake hits near elite Santa Rosa country club

They began with a 7-mile hike down to Cottonwood Campground on Saturday, Aug. 29, unaware that a once-in-a-century storm was brewing.

Their day started well before dawn, and Sumaruk told SFGATE that even at that early hour, the skies were dark and occasionally stormy. By late afternoon, however, the storm clouds had built up even further, culminating in an afternoon monsoon that dumped more than an inch of rain into the canyon in just half an hour. 

The ensuing flash flood swept through a narrow portion of the canyon known as the Box, sending walls of water up to 15 feet high careening down Bright Angel Creek and Phantom Creek toward Phantom Ranch.

Flash floods are a common occurrence across the southwest, particularly during the summer monsoon season. Yet their power can only truly be understood by those who have experienced them. The stories emerging from the canyon’s depths are harrowing, speaking to the power of the landscape and the speed at which the danger arrived. Visitors describe having just moments to scramble to higher ground. 

“You could see trees, branches, all kinds of stuff being tossed around inside, and if someone had fallen in, it seems unlikely they’d have been able to climb out,” Sumaruk said. “I’d never seen a flood like that before, and I was really blown away by the sheer power of it.”

The flood, which arrived at the popular backcountry outpost around 2:30 in the afternoon, led to two deaths and major damage to the canyon’s inner infrastructure. A third man still remains unaccounted for. 

A day to remember

Sumaruk and his friend arrived at the park’s Cottonwood Campground shortly after lunchtime and were preparing for a leisurely afternoon when the day’s biggest storm rolled in. The rain and wind picked up within moments, and Sumaruk dove into his tent to keep it from blowing away. “Most of the storms before had only lasted maybe five to 10 minutes, but this one continued and had a lot of intensity,” he said.

As he lay inside, Sumaruk heard what he thought was thunder, except that it continued to grow louder. “At that point, I realized what it really was, which was the flood coming down the canyon. You could hear boulders moving,” he told SFGATE. “I unzipped my tent and saw this huge wall of water, and you could already see manmade things along with all the debris. It wasn’t a choice. We just left everything.”

Sumaruk used a phone in an unattended ranger cabin in the campground to get in touch with staff on the rim. He let them know that a dozen people were sheltering on higher ground, trapped by flooding both above and below the camp. Later that night, a ranger arrived on foot and was able to coordinate helicopter rescues the next day.

Dave Gregory, a sales and marketing professional from Dallas, Texas, similarly arrived at Phantom Ranch just an hour or so before the rain started. He was traveling with a friend and the man’s two teenage sons, and had visited the canyon many times before in all seasons and conditions.

“I really enjoy getting outside, and the Grand Canyon has always been one of my favorite places to go,” Gregory told SFGATE. “It seems like every trip is unique, including this one for sure.”

The group set out on a short hike up the Clear Creek Trail before dinner when they noticed dark clouds moving towards them. They made the decision to turn around, but the storm moved so quickly that it overtook them before they made it back to Phantom Ranch. “We got drenched pretty good,” Gregory said.

Read more Tech layoffs climb as Uber sacks thousands of employees

Even as the storm grew in intensity, the word from rangers initially was that visitors may need to evacuate for a short time before being allowed back. Gregory was gathering his belongings in one of the ranch’s cabins when a park ranger arrived a short time later with a very different message: Everyone needed to evacuate to higher ground immediately. 

Gregory moved to the mule pens, where he watched another group of people flee, screaming, from a nearby maintenance shed, splashing through the rising water to join him. The ranger then directed visitors over a nearby footbridge to higher ground. Just 10 minutes later, the bridge was swept away, stranding about 50 people on the far side of the river. 

“It wasn’t immediately clear that some people had lost everything,” he said, adding that it was only when the helicopters arrived that people knew they weren’t going back. Some were left without their phones, wallets, or extra clothing, but in the end, Gregory told SFGATE he still counts their group as being lucky.

“When I heard about the fatalities, it was definitely more sobering,” he said. “It made me reflect, and maybe we were a little luckier than I thought.”

After being lifted out by helicopter, the evacuees were dropped on the South Rim of the canyon, where park buses took them to the park’s Maswik Lodge. There Gregory and Sumaruk say they were able to get needed supplies and that the park provided medical personnel, priests and mental health specialists. Park officials helped return people to their vehicles, and ultimately, Gregory returned home as scheduled.

“It was all very well done,” he said. “You could tell there was a plan in place, and the plan was carried out. I’m very thankful for all that the park staff did for us.”

Tallying the damage

Park officials are now working to assess the full extent of the damage, and it appears widespread. While much of Phantom Ranch remains intact, several campgrounds were inundated, and nearly all of the bridges have been destroyed. Images from the scene show snags of debris piled around trees, bridge pilings jutting from the mud, and large construction equipment jumbled among boulders. The entirety of the North Kaibab Trail, parts of the South Kaibab and Bright Angel Trails, the Cottonwood and Bright Angel campgrounds, Phantom Ranch, and the Silver and Black bridges are closed until further notice, with no estimated date for reopening.

A crucial pipeline that provides water to the South Rim was also damaged, with early estimates suggesting as much as 40% of the line may have been destroyed. The 12.5-mile Transcanyon Waterline pumps water from the Roaring Springs source on the North Rim across to the South Rim, and was nearing the end of a $208 million dollar replacement project when the flood struck. Without it, the park’s reserves hold about three weeks of water, and park officials recently closed all overnight lodging to conserve the little water they do have. Campfires have since been banned, as the water supplies not just restaurants and campgrounds but firefighting efforts as well.

The park’s hiking season may be coming to an early close, even as the country prepares to celebrate Labor Day on Sept. 7. In the past, the holiday weekend has been among the busiest times in the park, matching peak summer numbers with tens of thousands of visitors each day. But given the scale of the devastation, it will likely be months before hikers can once again venture to the canyon’s bottom.

“Obviously the canyons change, it’s what they do, but it is odd to think you might be the last to see things the way so many people remember them,” Sumaruk said. “I’ll be back though, to finish what I started.”