Mount St. Helens Erupts: 57 Dead, Billions in Damage

A magnitude 5.1 earthquake shook Mount St. Helens at 8:32 AM on May 18, 1980, and the entire north face of the mountain slid away in the largest landslide in recorded history. The collapse released a lateral blast of superheated gas and rock that traveled at 670 miles per hour, flattening 230 square miles of forest in minutes. Trees four feet in diameter were snapped like matchsticks and laid out in parallel rows pointing away from the crater. Fifty-seven people died, most of them outside the official danger zone that geologists had established. The mountain had been rumbling since March, when a series of earthquakes and small eruptions signaled that magma was rising inside the volcano. A massive bulge grew on the north face, expanding outward at five feet per day. Scientists warned that a major eruption was likely, and Governor Dixy Lee Ray established a restricted zone around the mountain. But the zone was not large enough, and several residents and loggers refused to leave. The lateral blast was followed by a vertical eruption column that rose 80,000 feet into the atmosphere, depositing ash across eleven states and several Canadian provinces. Mudflows of volcanic debris and melted snow roared down river valleys at sixty miles per hour, destroying bridges, highways, and homes. Spirit Lake, at the mountain's base, was completely buried under hundreds of feet of debris. The eruption reduced the mountain's elevation by 1,313 feet. The economic damage exceeded $1 billion in 1980 dollars. The timber industry lost an estimated four billion board feet of lumber. Agricultural damage from ash fall was extensive across eastern Washington. But the eruption also provided an unprecedented scientific laboratory. Researchers have studied the mountain's recovery for over four decades, documenting how ecosystems regenerate after catastrophic volcanic events. Life returned to the blast zone faster than anyone predicted, with lupines and gophers leading the recolonization.