American Alpine Jounrna and Accidents in North American Climbing

Dehydration, Heat Exhaustion, California, Yosemite Valley

  • Accident Reports
  • Accident Year:
  • Publication Year: 1984


California, Yosemite Valley

On October 11, 1983, John DeVries, a New Zealand climber, required rescue from El Capitan as a result of heat exhaustion. (Source: John Dill, SAR Ranger, Yosemite National Park)


Paul Aubrey, DeVries’ climbing partner, had climbed several El Capitan routes previously. This was DeVries’ first; however, he had several years of climbing experience, including direct aid. Aubrey had always taken one liter of water per person per day on El Capitan climbs, and DeVries had done so on long mountaineering routes. Neither of them had experienced problems with this amount, so they relied on the same ration on this climb. The climbing went well. DeVries had no problem adjusting to El Capitan or to big wall techniques, and one quart of water seemed sufficient. Three or four days into the climb, they experienced one hot day with no difficulty. The next morning was another hot one. DeVries became exhausted while leading the first pitch. He was so affected that the team was able to complete only one more pitch that day, stopping at Island-in-the-Sky. Although they were one day from the top (at normal climbing speed) and had some water left, DeVries had drunk two or three times his ration that day and felt he could not go on. They called for help the next morning. (Source: John Dill, SAR Ranger, Yosemite National Park)

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