May 18 - Thar' She Blows Day

Posted on May 18, 2020

Mount Saint Helens, in Washington, "before" pic

The signs were clear:

On March 20, 1980, Mount Saint Helens in Washington state (U.S.) experienced a pretty big earthquake. 

On March 27, 1980, the volcano started venting steam and ash.

On March 29, 1980, a new crater could be seen - and the mountain was topped by a blue flame in both craters!

On March 30, 1980, instruments on Mount Saint Helens measured 93 separate tremors (small earthquakes).

The experts agreed: the volcano was active, and it would soon erupt. Scientists told governmental officials and other policy makers, and the governor of Washington declared a state of emergency on April 3, 1980. He created a "red zone" around the volcano, and anyone caught inside the zone without a pass would receive a fine or a 6-month jail sentence (!). Outside the red zone was a blue zone where workers in mines and lumber were allowed - again, only with special passes.

Some curious people ignored the rules and moved highway barricades so they could get close enough to glimpse the volcano and get a taste of danger. Some people who had cabins in the red zone were bummed that they weren't allowed to go to their own property. 

At the end of April and early May, a bulge grew on northern part the mountain, and the area behind the new bulge started to sink. Even more looky-loos came to watch.

Thank goodness, on May 16, the visible eruptions stopped. So a lot fewer curious types came. Still, the public put so much pressure on officials, asking to go to their cabins and get their stuff out, that on May 17, officials bowed to pressure and allowed 50 cars and trucks of property owners into the red zone. They grabbed whatever property they could carry out.

Another property-owners trip was scheduled for 10 a.m. the next day...

But at 8:32 a.m., on May 18, a 5.1 earthquake hit the volcano, and a huge landslide (the largest in recorded history) began, moving across a lake and through a river valley. The landslide caused a giant wave of displaced lake water - about 600 feet (180 m) high - which in turn caused a 295-foot (90 m) avalanche of debris.

A few seconds after the landslide started, gases and partially molten rock exploded sideways, releasing ash and pumice, overtaking the landslide and fanning out into a 23-mile by 19-mile devastation zone. The blast had the force of an atomic bomb; actually, I read that it was the equivalent of 1,500 atomic bombs!

This was the most deadly and economically destructive volcanic eruption in the history of the contiguous United States (the 48 states excluding Alaska and Hawaii). Around 57 people were killed directly by the eruption. 

Only three of the people killed were in the red zone: a scientist, a photojournalist, and a man who refused to leave his home. The first two were dedicated professionals who were on the job.

David A. Johnson
 The scientist, David A. Johnston, is credited with saving a lot of lives, as he had publicly insisted that the eruption would be very dangerous. The last anyone heard from Johnston was his radio report - the FIRST report anyone heard of the eruption - "Vancouver! Vancouver! This is it!" Even though he was six miles from Mt. St. Helens, in what he hoped was a safe place, the side-blow of the volcano rather than the expected "blowing its top" almost instantly killed Johnston.

The third man who died in the red zone, the man who refused to leave his home despite warnings and urgings from officials, was quite old, and he wanted to live and die on the mountain. So he got his wish.

Three of the 57 people who died in the eruption were miners carrying permits to work in the "blue zone." Luckily the volcano's big eruption was on a Sunday, because around 300 lumberjacks were NOT working in the blue zone.

The rest of the 51 people who died in the eruption were all in areas deemed safe. But the thing is, scientists and experts know a lot, but there are so many unknowns in the universe, especially when it comes to volcanoes; who could have guessed that the volcano would start to bulge in one direction and then "blow its side" instead of its top? And who can know exactly where landslides and avalanches and streams of lava and other pyroclastic flows (hot gas and other volcanic material) are going to go? And who can guess at just how big an eruption is going to be?

I read about a family of four who took a drive hoping to see an eruption, and about a couple who went camping on a bluff. All of these people stayed in what had been thought to be a safe area. A relative of one person who died said that the state owed her and other loved ones an apology.

And yet: When experts and officials are telling you that a volcano is going to erupt soon, you maybe want to stay WAAAYYY farther away than just 4 miles into the "safe" zone. You maybe don't want to go to that particular mountain region for camping or hiking or picnicking or fishing, or "just a drive," even if it takes months for the expected eruption to occur or for scientists to give the "all clear" signal.

Although volcanic ash from the Mount Saint Helens eruption ended
up traveling around the world (It took two weeks), the amount
of ash in nearby towns was very unhealthy!

Mount Saint Helens, in Washington, "after" pic

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