Hiker Fatality along the Thunder River Trail in Grand Canyon National Park

On September 4 at approximately 7:30 p.m., the Grand Canyon Regional Communications Center received a report of a deceased backpacker along the Thunder River Trail, approximately one mile from the confluence of Tapeats Creek and the Colorado River.  

The backpacker, Delphine Martinez, 59, of Window Rock, Ariz., was on a multi-day backpacking trip. Hiking down the Thunder River Trail on September 4, she became disoriented and later unconscious. Trip members attempted resuscitation efforts without success. On September 4, high temperatures in the inner canyon were well over 100°F (38°C), with the high temperature at Phantom Ranch approximately 115°F (46°C).

Park rangers at Grand Canyon National Park urge visitors to Grand Canyon, especially inner canyon hikers and backpackers, to be prepared for excessively hot days in the coming weeks. In the summer, temperatures on exposed parts of the trail can reach over 120°F (49 °C) in the shade. Park rangers strongly advise not hiking in the inner canyon during the heat of the day between the hours of 10 a.m. and 4 p.m. Hiking in extreme heat can lead to serious health risks including heat exhaustion, heat stroke, hyponatremia, and death.

An investigation into the incident is being conducted by the NPS in coordination with the Coconino County Medical Examiner. No additional information is available at this time.

-NPS-

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