IT'S NEARLY NOON, AND THE MORNING'S HIKERS scramble out of the baking inner canyon, wheezing and dripping. In a room a few hundred yards from the South Rim, supervising ranger Marc Yeston touches a green pen to a wall map and traces a long, wriggling path. Then he makes a triangle.
Here, he says, is the spot where they found Margaret Bradley, a 24-year-old University of Chicago medical student and marathoner.
Just three months before, the 115-pound Bradley had finished the Boston Marathon in a few ticks over three hours, a solid performance in temperatures well over 80.
"I focused on keeping myself hydrated," she told the magazine Chicago Athlete afterward, "and not letting the adrenaline from the crowd make me do something stupid."
But last month, when she and a companion decided to try a 27-mile trail run in a single day, that caution was missing. A cascading series of miscalculations, say rangers, turned this scholar-athlete into the Grand Canyon's first dehydration fatality in four years.
Telling her story, rangers look to their feet, grope for words, trail off in midsentence. She was younger than most of them, and probably fitter. And now all that was left was an excruciating lesson in miscommunication and biochemistry.
In a single hour, a hiker in desert heat can easily lose a liter of moisture through sweat -- maybe, some experts say, as many as three liters (a liter is slightly more than a quart).
Without water, write authors Michael P. Ghiglieri and Thomas M. Myers in their book "Over the Edge: Death in Grand Canyon," dehydration, hyperthermia and exertion in the canyon can "turn people, inch by inch, into heat zombies.... Kids and young adults seem to run at full function in the heat, sweating appropriately and seemingly going strong, but abruptly, when dehydration kicks in, they crash quickly and often unexpectedly. And die."
Those threats are compounded by the shape of the land: Mountains rebuff the unfit and unprepared in short order, but the canyon -- "the upside-down mountain," locals say -- begins as a pushover, all downhill trail and mild temperatures at 7,000 feet. For decades, with signs, brochures and newsletters, rangers have struggled to make hikers understand the challenges that wait below.
These challenges are serious enough that the park created a special Preventative Search and Rescue unit seven years ago after a flurry of dehydration and heatstroke cases in the canyon. Most summer days, rangers station themselves a mile or two or three down the busiest trails, chatting up hikers as they pass, checking to see if fitness and water supplies match their itineraries.
But it's a tricky job, because rangers can't watch every trail and a ranger can't order a hiker off the trail for seeming unprepared. And at least once a day, says supervisor Bonnie Taylor, somebody defies her warnings and heads on down.
"Our job is not to harass them," Taylor says. "Our job is to understand that they understand the situation here."
Before she headed to college in Chicago, Bradley was raised in Falmouth, Mass. She hadn't spent much time in the desert. But she wasn't easily daunted.
At the University of Chicago, she had earned a double degree in biology and Earth sciences, then went on to med school. She played violin in the university symphony and worked summers at the Marine Biological Laboratory in Woods Hole, Mass. And as a runner, putting in up to 90 miles a week, she'd competed in Division III national championships and earned all-American status.
To prepare for the canyon, she ran in the hills around Flagstaff for a few days. She also found a running partner, a Flagstaff man in his late 20s or 30s with whom she shared a Chicago connection. On July 8, they agreed to take on the canyon.
Rangers interviewed this man. They say they are not accusing him of wrongdoing and have refused repeated requests to identify him, citing his privacy and saying Bradley's family asked them to omit his name from public accounts. (A Freedom of Information Act request by The Times is pending.) Bradley's parents declined to comment for this article.
At least part of the tale, however, can be gleaned from rangers who were there. By Park Service accounts, the runners began their day about 9 a.m. at Grandview Point, the highest spot along the canyon's South Rim, where the trail head is 7,400 feet above sea level, nearly 5,000 feet above the river.
Here is where the two runners made their first mistakes. They set off nearly four hours after sunrise, several hours later than rangers advise distance hikers to begin on summer days, and they were traveling dangerously light. Bradley's companion had four liters of water. She carried fruit, three protein bars and just two bottles of water (about 1.5 liters). They carried no maps, and Bradley apparently had no flashlight or headlamp.
From Grandview Point, the two headed down an unmaintained, waterless path built by a prospector about 100 years ago, descending 2,600 vertical feet in just three miles. From there they planned to descend farther, then follow the Tonto Trail across the notoriously hot and shadeless Tonto Plateau, about 1,000 feet above the river. Then they'd climb back out on the busier South Kaibab Trail, which tops off at 7,000 feet.
It's unclear why they thought they could do this route in a day, or where they expected to get water. "Not recommended during summer," says the Park Service's free trail guide. "No water."
"This would be a two- or three-day backpack trip with a lot of planning," says Yeston, who served as incident commander. "And the optimum time to do it would be fall," adds Ken Phillips, the park's search and rescue coordinator.
The dicey distance, the scant supplies: Is this the kind of hubris that could afflict any gonzo hiker or runner? In runners' chat rooms, speculation has been divided between those who see this as rare bad judgment and those who see it as an all-too-common mistake that happened to wind up more dramatically than most.
"It doesn't make sense ... but people do it all the time," one runner wrote.
In the first seven months of this year, park personnel have carried nearly 200 hikers out of the canyon by helicopter, most of them suffering from "environmental causes" -- exhaustion, dehydration, sometimes water intoxication, which happens when hikers drink plenty but fail to take in salt to help keep their electrolytes balanced.
Among runners, there's always a temptation to carry as little water as you can get away with, because it's heavy. A single liter weighs more than two pounds. If they followed the canyon rangers' recommendations of one to two liters for each hour on the trail, every runner and hiker on a four-hour excursion would set off with eight to 16 pounds of water on board.
But if your starting point is the Grandview Point trail head, it doesn't take long to realize the rangers have a point. For every 1,000 feet in descent, canyon veterans say, the temperature is likely to rise 3 to 6 degrees. At the river's edge that day, the high would be 105.
By 3 p.m. they were in trouble. Bradley's companion couldn't run anymore. He stopped, overheated and exhausted, and curled up in the shade of a bush to rest. In six hours they'd covered about 12 miles, with 15 still to go. Now the temperature was over 100, and their water was gone.
As a hiker heats up, says Yeston, "the body is going to start to divert blood to the parts of the brain that are more basic. The parts of the brain that you might have used to make nuanced decisions about your situation -- they're compromised. Long before a person seems drunk or delirious, they're already going to have a subtle loss of fine motor coordination and critical thinking ... and even difficulty referencing past experiences."
The two made a fallback plan, rangers say the companion told them later: He would stay put, and Bradley, the stronger athlete, would go on.
This, rangers and others say, was another big mistake. Hikers almost always fare better by sticking together. But in a short life, Bradley had learned to outrace common expectations.
"She was incredibly tough mentally," says Paul Peters, owner of the Universal Sole running-shoe store in Chicago. "Really intense but always smiling."
Bradley, who lived near the store, joined its running team last fall as part of her training for the Boston Marathon. She'd join in for burgers and beer after Monday-night fun runs of eight or 10 miles, and she'd hang out at the store during her rare idle hours, always angling to learn some new training techniques from the other serious runners who worked there. She'd run hard in a 5K in New York on a Saturday, then do an 8K in Chicago the next day.
"No matter what the conditions, no matter what was going on, she would go out and try to win every race she ran," Peters says. When he heard about what happened in the canyon, he adds, "I could definitely see her pushing herself beyond what anybody else would have done, in terms of not stopping until her body just gave out."
Now, instead of following the Tonto Trail to the South Kaibab Trail, then heading up and out as the two had planned, Bradley would look for help and water. She would follow the Tonto to the South Kaibab, but turn downhill toward Phantom Ranch at the bottom of the canyon. That meant 11 more miles.
Without a partner, she did what she was exceptionally good at: She persisted.
In the early hours of the next day, Bradley's companion woke alone and parched on the Tonto Plateau. But it was cooler now, and he felt well enough to make his way toward the South Kaibab Trail. He believed he saw the tracks of Bradley's Reeboks, according to rangers.
Near the intersection of the Tonto and Kaibab trails, he was saved: A U.S. Geological Service employee, who was carrying a satellite phone, spotted him. The USGS employee came to his side, found him suffering from exhaustion and dehydration, and used the phone to get a ranger's directions to an emergency supply of water cached nearby.
This was about 7 a.m. Friday, about 22 hours after the trail run began, and it could have marked the beginning of a campaign to find Bradley. But "nowhere in that conversation did we get information that he was a runner, that he'd crossed the Tonto, or that there were two of them," says Yeston. (The USGS employee declined to be interviewed for this article.)
Apparently, the companion had come to believe that Bradley had reached Phantom Ranch. Somehow -- and the rescue rangers shake their heads at this -- the runner hiked out of the canyon (with the phone-bearing USGS employee as his guide), held conversations with a commercial guide and a trail crew worker, and got a ride back to Flagstaff, yet never transmitted the idea that his partner might need rescuing.
Through the trail crew worker, he did send a message to Phantom Ranch for Bradley, explaining that he'd abandoned the hike and would leave her car at the South Kaibab Trail head on the South Rim. But that information alone set off no alarms; rangers and Phantom Ranch staffers hear several times a day from separated hikers rearranging their plans.
Meanwhile, Bradley's family had planned to meet her on Friday afternoon in Flagstaff. When she didn't show, the family reported her missing to Flagstaff police and rangers between 1 and 4 a.m. Saturday, setting off a flurry of phone calls to local lodgings.
By now it was about 18 hours since Bradley's companion had encountered his USGS rescuer. But still, nobody in authority knew the whole story.
That moment of horror and recognition didn't come until about 6:30 a.m. Saturday, when Bradley's brother reached her trail companion by telephone. The companion then called the park's dispatcher at 6:50 a.m. -- "and now," says Yeston, standing by the map -- "all the dots connect."
Within 90 minutes, the Park Service had 20 people on the case. Within five hours, a Park Service helicopter crew had spotted a body at Cremation Creek, 200 to 300 feet below the Tonto Trail. Before he was rescued, her companion kept descending on the trail and must have passed within 500 vertical feet of Bradley. The pilot brought the chopper closer to see if the roar and rotor wash would rouse her. Nothing. Margaret Bradley was gone.
"She was in a sleeping position, using the pack as a pillow," Yeston says. "A fetal position."
A red visor lay near the body. An uneaten protein bar, not much good for hydration, was in her pack. The rescue team pronounced her dead at 2:25 p.m., says Jeremy Thompson, forensic examiner for Coconino County, and estimated time of death at 12 to 24 hours before that. The USGS employee with the satellite phone had run into her partner about 31 hours earlier.
After an autopsy, the medical examiner classified the cause of death as accidental "dehydration due to environmental heat exposure."
Given the way light and heat bounce around in the depths of the canyon, rangers say, the temperatures that Friday at Cremation Creek could easily have reached 120 degrees. Like many thirsty, desperate and often delirious hikers over the years, Bradley had apparently decided to leave the trail and blaze a more direct route to the water.
"When all that stuff comes over you, and you realize you're approaching what you've read about ... it's an almost overwhelming disorientation," says Michael Olson, a longtime triathlete and marathoner from Flagstaff. Olson, 39, says he has made the 23-mile rim-to-rim run half a dozen times, always in October, and would never touch a Grandview-Tonto-Kaibab itinerary in the summer.
Leaving the trail, Bradley had descended two dry waterfalls and then a 20-foot "pour-off" cliff without injury, only to find a 50-foot cliff waiting next, reports Tom Clausing, the park's emergency medical services coordinator, who was among the first to reach her body.
"She slid into a natural terrain trap, from which there was no climbing out," Clausing says. She wound up about 500 feet above the waters of the Colorado.
Clausing wonders whether it was day or night when Bradley made those decisions. The South Kaibab Trail, he says, is nearly visible from the area where she must have left the Tonto Trail. If she'd stayed on the Tonto for another mile, Clausing says, she'd have hit the South Kaibab Trail, where a Park Service telephone waits and foot traffic is thick.
"She'd have run into 100 people the next day," Clausing says.
Later, rangers retraced the hikers' paths, alert to possibilities of deliberate wrongdoing. They found "not even a hint of it, and we looked hard," Yeston says.
Bradley's death, with its long list of improbable contributing circumstances, resonates differently for many of those who worked to prevent it.
"This was a very tough one for us ... a preventable tragedy," says Phillips, the search and rescue coordinator. "Two athletes, and the one that's more fit is the one that ends up dying."
The next morning, 13 days after Bradley's death, ranger Bonnie Taylor is working a preventative rescue shift on the scorching Bright Angel Trail.
In the space of an hour, Taylor will gently, or bluntly if it seems necessary, urge several hiking parties to trim their ambitions or drink up on the spot. Young and old, men and women, kids and couples, fit and flabby: She approaches them all. She likes to start by asking where they're from, because it hardly matters how they answer.
"Nobody," she says, "is from anywhere that's this hot."