Date of Event:  8/25/2013

Canyon involved:  Behunin

Region:  Zion National Park, Utah 

Country:  USA

Submitted by:  Dave Nally

Source:  “Deaths & Rescues in Zion National Park” by Dave Nally

Injury:  Hypothermia, Psychological

Cause:  Swiftwater, Flash Flood Weather

 

Description of Event:  On August 25, 2013, a group of four canyoneers barely made it down the final rappel in Behunin, just as the steady rain began to pour down like mad. After the fourth man got down off the rope, they all cheered (an online video was posted), thinking that they were “off the hook.” But then the pour-off 165 feet above them immediately began flashing so hard, that they could not pull their rope down in time. Not wanting to abandon their rope, the foursome took cover nearby, and were soon trapped under a boulder for quite some time, as immense waterfalls penned them in. They became hypothermic while huddling under the boulder for more than an hour, due to copious amounts of floodwater spurting through the boulder cracks, and squirting on them from all angles.

 

Author’s Analysis:  

-An understanding of weather is critical to safe canyoneering. Before entering a canyon, determine which weather service is most accurate for that region. Local residents may forecast the weather more accurately. Monitor the weather throughout the day. Consider escaping to high ground and waiting out a storm if needed. Becoming familiar with the effect of geographical features such as slickrock is important. 

-Always carry emergency gear to survive the night. This may include the ability to start a fire, dry clothes, survival blanket, extra food, and first aid supplies.

-Table: common signs and symptoms of hypothermia.

 

Stage Core body temperature Symptoms
Mild 90-95 °F

32-35 °C

 Shivering; poor judgment; amnesia and apathy; increased heart rate; increased breathing; cold or pale skin
Moderate 80-90 °F

27-32 °C

 Progressively decreasing levels of consciousness and stupor; shivering stops; decreased heart rate and breathing; decreased reflexes and no voluntary motion; paradoxical undressing
Severe < 80 °F

<27 °C

 Low blood pressure and bradycardia; no reflexes; loss of consciousness; coma; death

 

ICAD Analysis:

Regardless of weather forecasts, teams should be prepared to spend the night in the canyon and deal with worse-than expected, adverse, weather conditions or other injuries. Keep in mind that hypothermia can occur even in warmer temperatures (eg. due to heat loss via contact with rock or water, or surfaces colder than body temperature) and even warm water. Some environments are also prone to large temperature swings throughout the day or in the evening, and windchill can result in considerable heat loss as well. A team may not be cold when moving, but if it is forced to stop and shelter, minimizing evaporative cooling and environmental protection (particularly if the stop is going to be prolonged) is essential, as it is generally easier to shed heat than it is to gain it when it has been lost in a canyon.

 

Environmental protection and emergency equipment doesn’t necessarily need to be complicated or expensive, and can be life saving in an emergency. For instance, large garbage bags are lightweight, inexpensive, and can be used to insulate from the wind and water, or can be stuffed with leaves to make an improvised sleeping pad along with other equipment (eg. packs, ropes, and partially inflated drybags can keep you off the ground at night). Extra calories and food intake can increase body temperatures as the body metabolizes that food, and groups can huddle together to minimize wind exposure or protect more vulnerable/hypothermic team members.

 

Teams should also consider pre-trip planning and communication as a vital part of success; operating as a team, equipment can be distributed and checked beforehand, and discussions about contingencies and potential scenarios not only prepares teams for those contingencies, but also helps individual team members develop that mindset and experience.