A kayaker pushed off the jagged rocks of the Virginia shoreline below Great Falls on Friday afternoon, and the swirling, churning water immediately pulled his boat into the swift current of the Potomac. He thrust his paddle into the water to regain control and battled his way upriver toward the falls, the little orange kayak bouncing through cold waves in a course both grueling and graceful.

A helicopter hovered just overhead, a reminder of just how dangerous the river can be. Police were still searching for the body of an expert kayaker who got into trouble last Tuesday afternoon in rapids called Grace Under Pressure and disappeared in the falls just below.

Authorities say Todd Andrew most likely was forced underwater by the powerful river and pinned into a submerged hole or a cave there. He was the second kayaker to die on the Potomac this month.

Although the river flows at a placid pace downstream from Washington, the falls just 15 miles northwest of the city is renowned for its raging whitewater. For many in the kayaking community, the recent deaths raise questions about risk and responsibility in an area that has become a great lure.

On some summer evenings, recreational kayakers slip into the Potomac by the hundreds. Members of the U.S. whitewater slalom team train here. A neighborhood in Bethesda is full of athletes drawn to the easy access to the river; bright boats lean against garages in Brookmont, and neighbors meet after work for evening paddles.

To ride the rapids in a kayak, people learn to read the river, charting a course to dance between rocks and hydraulics, currents that can spin the water with relentless, pounding force. But even the most experienced boater can't always recover after going under.

Todd Andrew came to the Potomac to ride Great Falls. A 35-year-old from Spearfish, S.D., he had traveled to rivers across the country. He came with a friend from Virginia who knows the falls as well as anyone, local paddlers said, and they ran it several times Tuesday before the accident.

Andrew came out of his boat after Grace Under Pressure and the current forced him into a narrow chute over the last drop of the falls. "I know the spot where he disappeared," said Davey Hearn, an Olympian and now a coach who lives in Brookmont. It's a labyrinth of rocks, Hearn said, some as big as a conference table or a Volkswagen, with water surging through and around.

That was the last time Andrew was seen, as he went under.

Last year, Andrew was boating with another expert kayaker on Montana's Clarks Fork River when his friend drowned in the rapids.

Andrew told a local newspaper, "He died doing what he truly loved."

A Growing Sport

Thirty-five years ago, no one thought kayakers could survive Great Falls, the steepest fall-line rapids of any river in the east, a series of cascades, hydraulics and rocks.

But there weren't that many people out there paddling then. "Used to be you'd drive down the road, see a boat on someone's car, and you'd know who it was," Hearn said. "You'd wave."

A few hard-core paddlers rode Great Falls in the mid-1970s, keeping it secret to avoid getting banished from that stretch of the river. Over the years, kayakers worked out an informal agreement with authorities, and running the falls became so common that now there's an annual race there.

Kayaking took off in earnest in the 1990s. Equipment improved, making it easier, and the popularity of extreme sports pushed athletes to take on harder runs.

Old-timers say that means that there are young paddlers out there who take on tough rapids but have not had years of experience with techniques such as rolling themselves upright when the kayak flips.

"They gain a lot of confidence very quickly" now, said Jesse Reynolds, the supervisory ranger at Great Falls Park, "and I tend to think they assume themselves [safe in] situations where they aren't truly safe."

Still, most of the Potomac's paddlers love the serenity of the river's smooth, flat stretches and would never risk going over Great Falls.

The river narrows before Great Falls, speeding up the current, and then it drops through a series of cascades. Kayakers on one route usually regroup in calmer water just before taking the final plunge, a roughly 22-foot drop, that took the lives of Andrew and another paddler six years ago.

In 1998, Scott Bristow went over Great Falls and disappeared. Many paddlers believe that he was caught in the pressure from spinning water, pushed into a spot known as Charlie's Hole. His body was never found.

Steve Goudy, who was carrying his kayak on his shoulder up the steep path from the river Friday afternoon, said the falls are too dangerous for him. With his helmet still on and water dripping off his life vest onto the trail, he said, "I know people who have run it hundreds of times, but for me, it's not worth it."

Respect for the River

Even with every precaution, the river has unknowns.

Many hard-core paddlers are cautious, knowing the strength of the river and how much is hidden below the surface.

Jeff Jarriel, a 40-year-old kayaker from Gambrills remembers when the water level dropped enough to see the riverbed. "It was extremely scary-looking," he said. Near the falls, "there's a huge cavernous room underwater. I remember paddling by thinking, 'Oh my God.' You don't even realize it's there when the water's up."

Hydraulics form when water comes over a drop, such as a dam or rock, creating a wave that curls back and heads upstream. They come in different shapes and sizes, and kayakers sometimes play in the biggest ones they can find. Other holes are more dangerous, pushing a boater toward rocks or not letting go, with relentless pressure from the water.

"You look at the falls and you think, 'My God, why would anyone want to run this?' " said Charlie Walbridge of American Whitewater, which is headquartered in Silver Spring. "But most boating accidents are caused by much more boring things."

About 20 people died nationally last year kayaking whitewater, Walbridge said. The number of deaths increased from an average of seven or so after the mid-1990s as the sport grew but has held fairly steady recently.

After the death in 1998, a group of paddlers, police and rangers developed a set of distress signals so that people in the water could communicate with rescuers.

Expert kayakers scout rapids, map their route, read the waves, plan what they'd do at each spot if they got in trouble, and go with a friend in case of the unknown, said Mac Thornton, a longtime paddler who helped found the Potomac Conservancy.

This year, five people drowned along the stretch of river near Great Falls; Andrew was the only kayaker. The other kayaking fatality this year occurred farther down the river, on a quiet stretch well south of the city. Michael Schoenfeld, a 62-year-old administrative law judge from D.C., drowned this month, his life jacket on.

Those who paddle in the whitewater have to respect the power of the river, Preston Hartman said. "We're in the river," he said, "so we understand the hydrology. The Potomac's a big river. It's very powerful. That's one thing that's so great about the sport -- just being in all that power."

Paddling toward the falls is like rising to the top of a roller coaster, the moment before the drop, said Joel Meadows, a kayaker from Virginia. The sound of the falls is thunderous, huge rocks jut out of the water, and the horizon suddenly appears through a cloud of mist.

It's too strong to fight. So a paddler takes a leap of faith: The kayak shoots off the edge and drops to the water of the Potomac underneath.

Jarriel said it's like standing next to a railroad track when a freight train rushes by. "You get that sense of raw power when it goes by you. Great Falls is like that, this amazing, big and powerful thing."

Staff researcher Bobbye Pratt contributed to this report.

A man in a kayak paddles near Great Falls, where another kayaker disappeared last week. Five people have drowned near there this year.