Washington state is home to 5 threatening volcanoes. Here’s what to know about them
Washington state is home to five volcanoes: Mount Rainier, Mount St. Helens, Mount Baker, Glacier Peak, and Mount Adams. According to the U.S. Geological Survey, all five of these volcanoes are listed as having high or very high threat potential.
The Washington State Department of Natural Resources collects information on the volcanoes’ threats, how to prepare for evacuation in case of eruptions, and more information to educate citizens on the specific volcanoes. The U.S. Geological Survey Cascades Volcano Observatory monitors the volcanoes and provides information on their status.
Mount Rainier
The last reported eruption of Mount Rainier was in 1894 by pioneers, but never confirmed. The volcano still releases gases and steam from its opening, as well as causing some day-to-day earthquakes. The DNR reports that 5,600 years ago the Osceola Mudflow, a debris avalanche that came down from Mount Rainier, filled valleys with about 400 feet of sediment at speeds up to 50 miles per hour. The latest major mudflow was in 1502, called the Electron Mudflow, and it’s estimated that Mount Rainier has caused about 60 of these large mudflow avalanches in the last 10,000 years. Mount Rainier is being monitored at highest priority and remains a potential threat even today.
Mount St. Helens
Mount St. Helens is known for the 1980 eruption that killed 57 people. The chain of events and eruptions caused debris to move at speeds of about 60 miles per hour, the largest avalanche in recorded history. The lateral blast from the explosion was recorded at about 650 miles per hour. Then between 2004 and 2008, minor explosions caused lava to build up in the volcano’s crater, growing a lava dome of 1,500 feet. Mount St. Helens is being monitored at highest priority and remains a potential threat.
Mount Baker
Mount Baker is one of the most recently newly active volcanoes in the Cascade mountain range, and erupts very infrequently compared to the others. The last time the volcano had a major eruption was about 6,600 years ago, but in 1975, surface activity and a collapsed crater concerned scientists but there was no eruption, according to the USGS. Steam and gas can still be seen coming out of parts of the volcano, but it is best known for its heavy snow in the winter, levels that even broke the world record for most snowfall in a season in 1999 with 95 feet. Mount Baker is currently being monitored as a highest priority threat volcano.
Glacier Peak
According the DNR, Glacier Peak is one of the more dangerous volcanoes in Washington state as the volcano frequently erupts and causes dangerous lava and mudflow. Glacier peak has had no signs of erupting for the past few decades but has a potential threat to severely damage Skagit and Stillaguamish River valleys. The last recorded eruption was about 300 years ago, but Glacier Peak is still being monitored for potential threats at the highest priority level .
Mount Adams
Mount Adams it the only volcano in Washington state that is only being monitored as a high priority threat, not highest priority. Mount Adams is the largest volcano by volume in the Pacific Northwest, but has not had as many eruptions in total compared to the others. The latest eruption was recorded to be about 1,000 years ago, and the volcano caused some avalanches and mud flows between about 300 and 600 years ago.
This story was originally published March 21, 2022 at 12:00 PM with the headline "Washington state is home to 5 threatening volcanoes. Here’s what to know about them."
CORRECTION: Mount Baker last erupted in 1843, according to the U.S. Geological Survey. The story was corrected March 22, 2022.
