Grand Canyon River Alert System—Implementing an emergency alert system for wilderness recreation

Joseph E Thomas; Thomas M. Gushue; Erica Byerley; Paul E. Grams

doi:10.3133/ofr20251027

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Grand Canyon River Alert System—Implementing an emergency alert system for wilderness recreation

Joseph E Thomas·Thomas M. Gushue·Erica Byerley·Paul E. Grams

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Abstract

The Grand Canyon River Alert System (GCRAS) provides government-issued emergency alerts to wilderness recreationalists in the Grand Canyon, who are often outside the bounds of cellular signal reception. GCRAS is a collaboration between the U.S. Geological Survey (Grand Canyon Monitoring and Research Center), National Weather Service, Coconino County Emergency Management, and National Park Service. Technological advances in satellite communications have improved satellite signal availability in remote areas and increased the reliability of satellite communications using personal devices such as commercially available satellite messaging devices. These advancements have presented an opportunity to create a novel emergency alert system designed primarily for backcountry visitors to provide improved communications for periods of increased risk and potentially dangerous situations in the backcountry. GCRAS is designed specifically for the distinctive needs of satellite messaging devices and features reduced character count messages, short-code signup capability, and the ability to unsubscribe at any time. After a positive test of the system in March 2024, the system went live to the public and has been used more than two dozen times in 2024 to inform boaters and hikers of hazards (such as debris flows and flash floods) in the Grand Canyon. Satellite signal availability and device response time varies based on location and service provider, but initial testing showed messages arriving within 2–10 minutes. Although GCRAS was developed specifically for the Grand Canyon, the GCRAS framework could be applied to other wilderness areas. It can be used by emergency management authorities, land-management agencies, search and rescue units, and those concerned with public safety to help increase communication with people visiting or living in areas that are outside the signal of more traditional emergency-notification methods, such as cellular, wireless emergency alerts, and sirens.

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Source-reported bounding extent: 35.58732870070932° to 36.823773492081415° latitude; -114.05083740896649° to -111.53233878502289° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Joseph E Thomas, Thomas M. Gushue, Erica Byerley, Paul E. Grams. 2025-06-25. Grand Canyon River Alert System—Implementing an emergency alert system for wilderness recreation. https://doi.org/10.3133/ofr20251027

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