Mount St. Helens


May 18, 1980 was a day that people living in southern Washington state will never forget -the day that Mount St. Helens literally blew its top. Here's the story.


IN 1774, Spanish captain Juan Josef Perez Hernandez sailed the harbors along the coast of what is now Washington state and British Columbia. Apparently, he didn't see such of interest and never bothered to stop. Four years later, English captain James Cook dropped anchor in one of those harbors, now known as Nootka Sound. Cook landed to stock up on fresh water and to trade with the natives. He took a few sea otter pelts back to the Old World, and soon otter pelts were being sold in Europe for $4,000 each, worth more than their weight in gold. Thus began the Otter Rush.

The Spanish claimed that since they had been the first to sail through the sound, the Nootka area belonged to them. The English said that since they had been the first to set foot on the land, they owned the territory. The English built a fort; the Spaniards seized an English ship in retaliation. War seemed certain until England sent Ambassador Alleyne Fitzherbert, Baron St. Helens, to Spain to negotiate a treaty. In 1790, the Nootka Convention was crafted to give both countries access to the area. Several years later, when Captain George Vancouver was exploring the Northwest, he saw a majestic mountain in the distance and named it after St. Helens. The native name was Loo-wit-lat-kla, meaning "keeper of the fire." It was an appropriate name for a volcano.

On May 18, 1980, it exploded.


Scientists knew an explosion was imminent in April of 1980, when a bulge 320 feet appeared on the side of the mountain, indicating that magma was pressing outward. The bulge was moving up at the sustained rate of 5 feet per day. Finally, the movement triggered an avalanche, which shook off the top of the bulge, exposing the white-hot interior to the air.

Under normal conditions, water can't be heated beyond the boiling point because then it turns to steam. But when it's kept under pressure (as in a pressure cooker) it can be heated beyond the boiling point and still remain liquid. When the pressure is removed, the super-hot water flashed into steam. Because steam takes up a lot more room than water, an explosion occurs. It's like carbon dioxide in soda: shake the bottle or can, and the gas wants to escape. Pop the top, and the release of pressure results in a mini-volcano of soda. That's what happened to Mount St. Helens.


The blast was heard all the way to Canada, The main eruption continued for ten minutes, followed by nine hours of explosive ash fall. The energy released was equal to 27,000 Hiroshima-sizes bombs dropped at the rate of  one per second, for nine hours. The volcano hurled 1.3 billion cubic yards of ash and rock into the air, enough to cover a piece of land a mile long, a mile wide, and as high as three Empire State Buildings.

The volcanic ash mixed with the water of surrounding rivers and lakes to form mud the consistency of wet concrete; it flowed downstream, wrecking everything in its path. An area stretching eight miles out from the volcano and fanning to a width of 15 miles was flattened. But the damage extended much farther than that. Eleven hundred miles of Washington roads were impassable, stranding 10,000 people. Police cars were stalled, train service halted, shipping channels clogged, and the power lines knocked out.


Two hundred square miles of wildlife habitat were destroyed. A million and a half animals and birds lay dead, as well as half a million fish. A hundred miles of streams were wiped out entirely, and another 3,000 miles of streams were contaminated by ash. Twenty-six lakes were removed from the map. One hundred twenty-three riverside homes were washed away, and 75 cabins were wrecked. More than 1,000 people were left homeless. In all, $2.7 billion in damage was caused in a single day.

Fifty-seven people died; the only survivor in the blast area was a dog who had been on a camping trip with his family. One man who died instantly when the blast hit was found in the front seat of his car with his camera still held in front of his face. Two young lovers in a tent were blown into a mass of fallen trees hundreds of feet away. They were found with their arms still around each other. Two people were killed in their car as they tried to outrace the ash cloud. Most of those who died in the explosion were killed by inhaling hot, toxic volcanic gases and ash. And most had violated orders to stay away from the area.


(Image credit: Rocky Kolberg)

Nearly half the state of Washington received visible ash fall. As much as 800,000 tons of it fell on the city of Yakima alone, 85 miles east of the volcano. In fact, so much ash was flushed into the Yakima sewer system that the treatment plant was shut down for fear of permanent damage. All over the region, water reservoirs were drained by communities trying to clean city streets and water rationing had to be imposed.

In Pasco, Washington, paper envelopes full of ash (mailed from residents to friends and relatives around the country) kept breaking open during processing, ruining the machinery. Someone in Seattle suggested drooping the "W" from the state's name and calling it Ashington. The ash cloud from the blast took 17 days to go completely around the globe. One disc jockey joked, "If you were planning on visiting Washington this year, don't bother. Washington is coming to visit you!"


(Image credit: Flickr user penjelly)

Today, bluebirds are plentiful as they nest in the abundant cavities found in the mountain's snags. Pocket gophers dig holes in the ash. Elk, which returned to the area only a few weeks after the blast, leave droppings, which fertilize the ash. Fireweed, with roots that reach the fertile soil beneath the ash, turn entire hillsides pink with flowers. Mosses, grasses, shrubs, and trees all took root again soon after the blast. The trees now stand over twenty feet tall in some areas. Nature recovers, and the mountain is heading back to normal. Except for one thing: the majestic vista that inspired Vancouver is not quite as majestic now. Mount St. Helens is 1,200 feet lower than it was before the eruption.





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Newest 5 Comments

"Two hundred square miles of wildlife habitat were destroyed."

Unbelievable! Outrageous! Call the EPA! Notify the Sierra Club! Calling all lefty dillweeds!

Sue! Sue! Lawyers! More lawyers!

I blame Bush!
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