The Volcano That Could Bury an American Town in 40 Minutes - Mount Rainier

The Volcano That Could Bury an American Town in 40 Minutes - Mount Rainier On a quiet weekday morning in Orting, Washington, the sirens start to wail. Classroom doors open, and thousands of children walk toward high ground almost two miles away. This is not a fire drill. They are practicing how to outrun a mountain. Orting is built on top of the Electron Mudflow, a lahar that roared down from Mount Rainier about 500 years ago. The U.S. Geological Survey ranks Mount Rainier among the highest-threat volcanoes in the United States, not because of lava, but because of lahars: volcanic mudflows that move like flowing wet concrete and can bury a valley in minutes. For Orting, a large lahar could arrive in as little as 40 to 50 minutes. In this documentary, we look at the Armero tragedy of 1985 in Colombia, where about 23,000 people died even though there were more than two hours of warning; the Osceola and Electron mudflows hidden beneath the towns of the Puget Sound region; the lahar warning system in the Puyallup and Carbon River valleys; the largest lahar evacuation drill in the world; and the 90,000+ people who now live in Mount Rainier's lahar hazard zones. CHAPTERS 0:00 The sirens of Orting 1:55 The most beautiful mountain in America 4:38 What is a lahar? The lesson of Armero 1985 8:29 A town built on an ancient mudflow 11:55 Forty minutes 15:52 90,000 people below the mountain 18:34 Not if, but when SOURCES & ARCHIVE FOOTAGE Footage, photos and maps courtesy of public-domain archives: U.S. Geological Survey (Cascades Volcano Observatory, video "Mount Rainier Lahars: Hazards for the Puyallup and Nisqually River Valleys"), National Park Service (Mount Rainier National Park), NASA, Washington State Archives and Wikimedia Commons (public domain). Debris-flow footage from Gyirong is used for illustration only. Further reading: USGS Mount Rainier: usgs.gov/volcanoes/mount-rainier USGS: Preparing for volcano hazards where the world's largest lahar evacuation drill is held USGS Fact Sheet 2008-3062: Mount Rainier - Living Safely With a Volcano in Your Backyard USGS: Holocene (post-glacial) eruptions and lahars of Mount Rainier Pierce County Emergency Management: lahar hazard maps and evacuation routes MUSIC "Darkling" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Ossuary 6 - Air" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Static Motion" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Scissors" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ "Lightless Dawn" Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 4.0 License http:/creativecommons.org/licenses/by/4.0/ Subscribe for more true stories about the hidden forces that shape America. This video is a documentary based on USGS and NPS research, historical records and scientific estimates. The lahar scenario is a scientific projection, not a prediction of a specific date. Some scenes use simulations or representative footage. #MountRainier #Lahar #Volcano