Whitewater kayakers know what they do is dangerous. Shannon Christy did, too.

The 23-year-old grew up around the water, in swimming pools, North Carolina rivers and the Atlantic Ocean, and she spent some summers teaching others how to navigate rivers safely. Then she discovered kayaking, and after college she started working for a kayak and canoe manufacturer while traveling the country seeking the next exhilarating whitewater run.

On Thursday, Christy was on the Potomac, having traveled up from Greenville, S.C., to participate in the annual Potomac River Festival and its Great Falls Race for expert kayakers. Her final Facebook post was a photo of her entry form for the race, which one longtime Potomac paddler said features the steepest kayak run in the world — a drop of 60 feet in 60 seconds.

Christy and another experienced kayaker hit the water about 3:45 p.m., with Christy going first and Will Seeber behind her. But something apparently happened when Christy went through the center lines of the Great Falls, and when Seeber spotted her again, she was swimming out of her boat in full paddling gear, according to a statement released by Active Nature, the sponsor of the event.

Seeber “attempted to come to her aid, but could not reach her in time before the fast-moving currents pulled Shannon into ‘Subway,’ ” one of the five “Fingers” flowing through the center of the falls and the most dangerous one. She became pinned underwater and drowned, authorities said. She became the third kayaker to drown in the area since 1998, according to Paul Schelp, a longtime kayaker and member of the Potomac Paddlers Volunteer Corps, which promotes safety on the river.

The Great Falls Race was canceled. Instead, the kayakers gathered at Overlook 3 in Great Falls Park on Saturday morning to remember her, then took to the river to spread flowers and spend some quiet time at the base of the Class V+ rapids, which are strictly for expert kayakers.

They mourned her death but had no second thoughts about the risks they take.

“For what we receive for playing on the waters and dancing with an element that is so much more powerful than us,” said veteran kayaker Pat Keller as he stood above the Potomac River on Saturday, “it’s worth going out again and again and again.”

Christy was a beloved member of the kayaking community.

“Every time she met people, in any circumstance, she was positive, happy and literally a ray of light,” said Jason Beakes of Poolesville, a longtime local kayaker and the founder of Active Nature. “Her personality, and what Shannon believed, represented us very well.”

Her family and friends said her deep faith in God gave her a particular confidence and focus in the moment.

“I really believe that her faith in her future, really diminished any fear that she had in any area of her life,” said her mother, Kim Christy. “She didn’t fear the future; she didn’t fear the river.”

Christy and her two brothers grew up first in Fort Myers, Fla., where their father built swimming pools, then along a river in central Florida and then to western North Carolina, where Christy worked as a river rafting guide, her mother said. “They grew up on the water,” her father, Lee Christy, said.

While working as a rafting guide, she noticed other guides spending their spare time in kayaks and took up the sport. At Western Carolina University, she began taking clinics to improve her technique.

“She would take any kind of instructional event where she could hone her skills,” her father said.

After graduating with a degree in mass marketing and communications, she took a job in 2011 in Greenville at Confluence Watersports, which makes kayaks, canoes and other paddling equipment. It combined Christy’s college degree with a sport she loved.

But her family said she wasn’t devoted to kayak racing. “She was competitive, but it wasn’t a competition,” Lee Christy said. “This race would probably have been her second or third race. She loved the challenge, but she mainly loved the people.”

For a time, she maintained a blog, ShannonChristy.com, subtitled “Feeling the rush,” where she detailed her outdoor adventures and described herself as an “all American girl that loves Jesus, ice cream, and whitewater.”

In a post about one whitewater run in a two-person kayak, she wrote: “Burton and I had no trouble until the very end of the run. We flipped and tried to both roll, then ended up swimming because we were unable to get upright. Looking back at the situation we both laugh and say we had too much confidence going into it. Next time!”

When Christy went first down the Great Falls on Thursday afternoon, “it suggests a high level of confidence,” said Schelp, who has been kayaking the river for many years and formerly organized and has won the Great Falls Race. The rapids are “just a wild ride,” but Christy had arrived in town a couple of days earlier and had already run it successfully. “Nobody will ever know what happened,” Schelp said.

Geoff Calhoun of Bethesda said he’d been watching people kayak Great Falls since he was 10, and “there’s a lot of caution that goes into paddling this.” He said being a local helps with the experience to navigate the rocks and differing depths. He knew Christy and said, “This is tragic. I’ll never get over it.”

Brent O’Neill, the site manager of Great Falls Park, said the kayaking community around the Potomac is smart and safe, but “the situation that happened to her can happen to anyone” if the circumstances are wrong.

Christy’s parents spent Saturday driving up from Andrews, N.C., to meet her friends in the kayaking world.

“We feel very blessed that we were allowed to share in 23 years of her life here,” her father said.

“Definitely,” her mother added. “It was easy.”