National Volcanic Monument - The Climatic Eruption of May 18, 1980
After 123 years of silence, Mount St. Helens resumed volcanic activity in March 1980. On March 27, seven days after the first earthquakes rumbled under the southwest Washington mountain, a steam and ash vent opened at the summit.
At 8:32 a.m. on May 18, 1980, a magnitude 5.1 earthquake triggered the largest landslide in recorded history. Reaching velocities up to 150 mph in only 10 minutes, the avalanche raced 15 miles and covered 25 square miles of the North Fork Toutle River Valley in debrits that measured an averange depth of 150 feet. Within minutes a lateral blast, equal to an explosion of 10 million tons of TNT, ripped through this sliding avalanche of debrits. The blast accelerated to 670 mph and to temperatures of 570 degrees F. (298.8 degrees C.) impacting 230 square miles. Ash clouds rose to 70 000 feet and on the first day of the exsplosion almost 50% of Washington State was covered in ash.
Mount St. Helens’ summit was left 1314 feet lower and today reaches 8363 feet above sea level. The damage to Washington State included $970 million in econimic losses, a great loss of wildlife and 36 known human deaths. Twenty-one people remain missing. Following the eruption mud flows and associated flooding caused additional, extensive damage to public and private proparty downstream on the Toutle and Cowlitz Rivers.
Weyerhaeuser Company, wich has owned and managed the St. Helens Tree Farm since 1900, was the largest private landowner impacted by the eruption. Nearly 68 000 acres, about 14% of the Tree Farm, were devestated. A total of 18.4 million trees were hand planted one by one in the Tree Farm a time after Mount St. Helens was secured. Areas in the blast zone was ready for thinning in the year 2000 with some final harvesting beginning in 2025. And the forest cycle will begin again.
Native People Living in the Shadow of an Active Volcano
The Story of Mount St. Helens is not only recorded in the rock layers and landscape that surround the volcano; it is also captured in the legends, oral histories, and written accounts of the people who through the ages have made Mount St. Helens their home.
Archeological evidence suggests that people have been living in the shadow of Mount St. Helens for at least 7 000 years. Excavations at places such as Lower Falls on the Lewis River help shed light on these prehistoric cultures and how they responded to the volcano’s periodic eruptions. For example, many archeological sites indicate that camps near the mountain were abondoned about 3 900- 3 500 years ago during the Smith Creek eruptive period. Native people did not return to live here again for another 1 500 years.
Of the Native American tribal groups that were located in Southwest Washington, the Klickitat and Cowlitz were most closely associated with Mount St. Helens. The Klickitat inhabited the areas between Mount St. Helens and Mt. Adams. They fished for salmon, hunted deer and elk, and gathered huckleberries, camas and other roots. The Cowlitz inhabited the Cowlitz and Toutle River drainageswhere they also followed a seasonal cycle of harvest. Both the Klickitat and the Upper Cowlitz called the vulcano LAW-WE-LAT-KLAH, or ”Smoker,” and both told stories of her beauty, youthfulness, and fiery temperament as is demonstrated by this Cowlitz tale:
Coyote went far up in the country. Making a snow mountain, He said: “This shall be called TAHOMA (Mt. Rainier)!”
Heading south, until TAHOMA was no longer visible, He said: “I will make another mountain, round at the top. This shall be called LAW-WE LAT-KLAH (Mount St. Helens)!”
Seeing it was too far away from the first, he made another mountain halfway between. He said: “This one should be called PATU (Mt. Adams)! This shall be the husband of the two others.”
They said that LAW-WE-LAT-KLAH got jealous of TAHOMA, and threw fire at her. She burnt TAHOMA’s head off, burnt her backbone and shoulders, too.
People still live in the shadow of Mount St. Helens. They are drawn by the volcano’s beauty, recreation and abundant plant and animal life. All that visit the volcano feel the awe of the area’s original inhabitants.