The fragile crust bordering Grand Prismatic Spring in Yellowstone National Park Troy Hendrickson

Yellowstone National Park remains a wild and sometimes fearsome landscape.

That's why four million people travel to the park every year to view untrammeled vistas, glimpse untamed bears and bison, and get close to hot gushing geysers and simmering thermal springs. But for unwary visitors, the extraordinary natural features that keep Yellowstone such an alluring place can also make it perilous. While backcountry hikers may be well aware that grizzlies and bison can be dangerous threats, Yellowstone visitors can get into serious trouble while wandering near the park's heavily visited geyser basins and other geothermal features.

Deaths and Injuries From Geysers and Geothermal Water

On June 7, 2016, Colin Nathaniel Scott, 23, of Portland, Ore., slipped and tragically fell to his death in a hot spring near Porkchop Geyser. He and his sister illegally left the boardwalk and walked more than 200 yards in the Norris Geyser Basin when the accident happened.

In June 2006, a six-year-old Utah boy suffered serious burns after he slipped on a wet boardwalk in the Old Faithful area. The boy fell into hot water that had erupted from nearby West Triplet Geyser. He survived, but more than 20 park visitors have died, the most recent in 2016, scalded by boiling Yellowstone waters as hot as 250 degrees Fahrenheit.

"Geothermal attractions are one of the most dangerous natural features in Yellowstone, but I don't sense that awareness in either visitors or employees," says Hank Heasler, the park's principal geologist.

The National Park Service publishes warnings, posts signs and maintains boardwalks where people can walk to get close to popular geyser fields. Yet every year, rangers rescue one or two visitors, frequently small children, who fall from boardwalks or wander off designated paths and punch their feet through thin earthen crust into boiling water.

Sign warning of dangerous ground conditions at Norris Geyser Basin in Yellowstone. Gloria Wadzinski

Yellowstone protects 10,000 or so geysers, mudpots, steamvents, and hot springs. People who got too close have been suffering burns since the first explorations of the region. During the 1870 Washburn Expedition exploring the region, Truman Everts was separated from the main party for 37 days and burned his hip seeking warmth from hot springs at Heart Lake. The first fatality, most likely, was a seven-year-old Livingston, Mont., boy whose family reported he died after falling into a hot spring in 1890.

Writing his 1995 book Death in Yellowstone, park historical archivist Lee H. Whittlesey sifted through National Park Service records to identify 19 human fatalities from falling into thermal features. The victims include seven young children who slipped away from parents, teenagers who fell through thin surface crust, fishermen who inadvertently stepped into hot springs near Yellowstone Lake and park concession employees who illegally took "hot pot" swims in thermal pools.

Following his parents along a boardwalk in the Old Faithful area in 1970, nine-year-old Andy Hecht from Williamsville, New York, tripped or slipped into the scalding waters of Crested Pool. He swam a couple of strokes, then sank in front of his horrified family. In 1981, David Allen Kirwin, a 24-year-old Californian, died from third-degree burns over his entire body. He dove head-first into Celestine Pool's 202-degree water, attempting to rescue a friend's dog.

Danger sign at Yellowstone Lake's West Thumb to warn those who may be tempted to veer off the boardwalk iStock

Another thermal fatality occurred in 2000. One moonless August night, 20-year-old Sara Hulphers, a park concession employee from Oroville, Wash., went swimming with friends in the Firehole River. Accompanied by two co-workers for Old Faithful businesses, Hulphers returned by hiking through Lower Geyser Basin. They carried no flashlights, and the three thought they were jumping a small stream when they fell into Cavern Spring's ten-foot-deep boiling waters. Hulphers went completely underwater and died several hours later from third-degree burns that covered her entire body. Her companions survived, but the two men spent months in a Salt Lake City hospital recovering from severe burns over most of their bodies.

Other Dangers: Drowning, Falling, Crashes

Of course, any national park can be hazardous, especially for visitors who don't pay enough respectful attention to the risks that come with entering any wilderness. As in other parks, some Yellowstone visitors die just about any year from drowning, falling off cliffs, and crashing vehicles.

Injury Incidents are Probably Higher Than Reported

Yellowstone is known throughout the world for its geysers and other geothermal features. Entrance station rangers hand out park newspapers that print warnings about the danger, but National Park Service safety managers say some visitors can't resist testing how hot the water is by sticking in fingers or toes.

"Most people who get thermal burns feel a little sheepish about it," Heasler says, and may not report the injuries to park rangers.

More serious third-degree burns are suffered by visitors who leave boardwalks and marked trails. They break through the thin surface crust up to their knees and their boots fill with scalding water. Some thermal waters are tepid, but most water temperatures are well above safe levels. People can sit comfortably in hot tub waters heated to between 102 to 105 degrees Fahrenheit, "but above about 120 degrees, you have an increasing chance of getting burned if you go in," says Steve Sarles, the Yellowstone ranger division's emergency medical services director. Most hand and foot burns can be treated at local hospitals, but Sarles says one or two people a year suffer more extensive third-degree burns over their bodies after falling into thermal waters with temperatures of 180 degrees or higher.

During the 1990s, 16 park visitors were burned extensively and deeply enough by geysers or hot springs that they were immediately flown to Salt Lake City for treatment at the University of Utah Hospital regional burn center. On average, they spent 20 days at the center being treated for their burns, and many go through skin grafts to replace damaged tissue. The most severely injured stayed 100 or so days, and some survivors are left with permanent disfiguring scars, says Brad Wiggins, the burn center's clinical nursing coordinator.

Some victims have faulted the park service for not erecting barriers and cautioning visitors more sternly about how dangerous thermal areas can be.

Shadows of visitors at Crested Pool in Yellowstone's Upper Geyser Basin NPS/Neal Herbert, Public Domain

In the early 1970s, the parents of Andy Hecht, the nine-year-old who died in Crested Pool, mounted a nationwide campaign to improve national park safety. They eventually settled a wrongful death lawsuit against the National Park Service. A Wyoming judge threw out a lawsuit by Lance Buchi, one of Sara Hulpher's friends, who was severely burned. Buchi contended that park officials failed to give adequate warning about thermal feature dangers.

"We try to educate people starting when they come through the gate," Brandon Gauthier, the park's chief safety officer says. Park managers have installed guard rails near some features, but they walk a fine line between giving visitors a chance to get close to popular attractions and ruining the natural landscapes that national parks were created to preserve. Rangers stress that it's important for parents to keep a close eye on curious and rambunctious children when they visit thermal areas.

"There are a lot more people around geothermal areas than in the backcountry," Gauthier says, and the unwary can get hurt badly if they stray off established paths.

People Will Do What They Want to Do Regardless of Danger

"There are many risks in Yellowstone," Gauthier adds. "It's something you've got to respect and pay attention to."

Sometimes, despite the park service's warnings, "people will do what they want to do," says Wiggins. When Wiggins took his own young children to the park's geyser basins, "I held onto them very tightly, and we didn't go off the trail. Yellowstone's a beautiful place, but it's also a very dangerous place."

Especially to those who behave carelessly or recklessly. Anyone who pays attention to warnings and stays on the boardwalks should be just fine.

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