A helicopter rescued hikers clinging to tree branches and perched on boulders as a flash flood tore through a normally quiet creek in Arizona, where unpredictable summer storms can rapidly wash churning torrents into canyons and trap those looking to take advantage of cooler weather after the rain.
Seventeen hikers were stranded Sunday in a scenic canyon on the outskirts of Tucson, just over a week after floodwaters killed 10 members of an extended family more than 140 miles to the north.
In southern Arizona, the final two hikers were lifted to safety Monday from Tanque Verde Falls after they spent the night stuck on the side of a cliff in a rocky, narrow canyon, authorities said.
There was no immediate indication that any of the hikers were seriously injured.
Though "everyone is accounted for and everyone is alive," the rescues were a reminder of the dangers of flash flooding during the monsoon, when bursts of heavy rain can overwhelm usually calm waterways, said Deputy Cody Gress, a Pima County sheriff's spokesman.
When rains ease triple-digit summer temperatures, people often go hiking when the danger of flash flooding has skyrocketed, the agency said. On July 15, a large family celebrating a birthday at a swimming hole in central Arizona was swept away by a wall of water that cascaded down a canyon without warning after a storm.
On Sunday, a police helicopter lowered a rescuer to eight hikers, including a 4-year-old boy, fastening them to a hoist that hauled them one by one to waiting rescuers on the side of the mountain creek.
Four were plucked from the creek as they clung to tree branches with water up to their waists, said Shelley Littin of the Southern Arizona Rescue Association who helped with the rescues. Others scrambled to safety on rock ledges, climbing as high as they could.
"They were standing on top of what was now a raging rapid," she said.
The creek normally has just a trickle of water, allowing people to play in shallow pools, but Littin said the water level jumped about tenfold in five minutes and was at least 6 to 8 feet deep.
"We were extremely lucky not to lose anyone," she said.
Rescuers helped seven hikers in a less dangerous area walk to safety by Sunday night. Crews dropped food, water and blankets to the two remaining hikers stuck on a ledge before they could be rescued Monday morning.
Littin and another volunteer rescuer spent the night on the side of the canyon opposite the pair to ensure they were safe.
The hikers were in several groups and spread out in the canyon when the flash flood hit, authorities said.
Multiple state hiking sites warn that Tanque Verde Falls is one of southern Arizona's most dangerous hiking locations. A flash flood that swept through the area in July 1981 claimed eight lives.
Tanque Verde Falls is a series of multiple waterfalls, none taller than 100 feet. Visitors often swim and picnic after a short hike to the lower falls, but the trail to the main falls is longer and more strenuous. The narrow canyon, about 350 feet deep, is littered with sharp rocks and cactuses.
The National Weather Service had issued a flash flood watch for a wide swath of southern Arizona on Sunday, and Tanque Verde Falls was within that area, said Gary Zell, a meteorologist in Tucson.
People going into mountains or other flood-prone spots should know the conditions before heading off, he said.
"They're not good places to be when there's a risk of thunder, lightning and heavy rain," Zell said.
The sheriff's department said people often decide to go hiking once it stops raining, not realizing that the water they see in the creek is from much earlier rainfall, not the storm that just ended.
"What's coming is a lot more fierce," said Gress, the deputy.