The eruption of Mount St. Helens at 8:32 on May 18, 1980 was a major geological event that continues to have many effects on the 150 square miles surrounding the volcano. This eruption is classified as the worst volcanic disaster in United States history. In this explosion, the mountain lost its conical tip and 1,300 feet in elevation. Fifty-seven people and hundreds of animals lost their lives.
Native Americans living in the area before the first Europeans crossed the United States to the area presently known as Washington State recognized the fiery potential of the mountain. However, a period of dormancy from 1857 until the 1980 eruption had led people to lay aside any fears of the mountain. The homes they had built at the base of the volcano were destroyed when the volcano erupted. In addition, the eruption caused serious economic hardship for many in the area.
The eruption began with an earthquake that also started an avalanche. In just minutes, rock and debris traveled into Spirit Lake and 14 miles down the Toutle River. A plume of ash shot hundreds of feet into the air. While locals reported not hearing any noise with the eruption, its sound was heard in Montana and California. Ash from the volcano filled the air for weeks following the eruption, affecting all of Washington as well as surrounding states.