May 18, 1980: Mount Saint Helens Erupts


Mount St. Helens is an active volcano located in Skamania County, Washington. In 1980, the volcano began to explode, starting with a series of volcanic explosions and pyroclastic flows on March 27. The explosions escalated on May 18, 190, with a major eruption, with a Volcanic Explosivity Index of 5, the most significant to occur in the U.S.

The eruption was the most disastrous volcanic eruption in history. It was preceded by 2 months of earthquakes and steam-venting, which began to prepare the volcano for explosion, but an earthquake on May 18 caused the entire weakened north face to slide away, and in addition to the eruption, lead to the largest landslide ever recorded.

The explosion itself rose to 80,000 feet (15 MILES) into the atmosphere, and ash was found in 11 different states and 2 Canadian provinces. Smaller explosions continued into the next day, followed by other larger ones later in the year, which were not as destructive.

Ultimately, at least 57 people died as a direct result of the eruption, including an innkeeper, photographers, and a geologist. It caused over $1 billion in damage and killed thousands of animals.


The last time Mount St. Helens was active was in the 1850s, and since then, the volcano had remained dormant with little of note. But on March 15, 1980, small, but frequent, earthquakes indicated that magma may have begun moving below the volcano. On March 20th, the volcano was considered active after 123 years of inactivity.

Much of the pre-explosion information is kind of difficult to understand, so I'll try to dumb it down, mostly for myself. Basically, a bunch of earthquakes began to occur in the area, to the point where there was about 5 4+ magnitude earthquakes a day. Avalanches were reported from aerial observations, but ultimately, there wasn't an immediate panic that eruption was imminent.

On March 27, there were "phreatic eruptions", or explosions of steam caused by magma suddenly heating groundwater, wreaking some havoc, as well as continued earthquakes. Some of the steam explosions sent ash up to 150 miles away. But still, it did not seem like the volcano was at risk of erupting.

It wasn't until April 1 when harmonic tremors, or the underground movement of magma, were detected that geologists were alarmed. The day before, 93 separate earthquakes were reported. Things were getting concerning, and a state of emergency was declared on April 3. A "red zone" was created around the volcano, and a $500 fine would be issued, or jail time was threatened, if anyone unauthorized was caught in the zone.

On April 30th, geologists announced the biggest immediate danger was a sliding bulge of the volcano's north face, and that movement could trigger a landslide, and subsequently, an eruption. Things continued as normal on May 7, and before the earthquake on May 18, about 10,000 earthquakes were recorded.

But on May 16, visible eruptions stopped. People weren't as interested in watching a volcano do nothing, and spectators decreased. Because America, after months of 10,000+ earthquakes and activity, there was one day without and area property owners demanded to get to their cabins to gather their things. On May 17, 50 carloads of property owners entered the danger zone. Another trip was scheduled for 10 AM on May 18.

On the morning of May 18, things looked about the same as every other day. The bulge hadn't moved in any concerning way, the sulfur dioxide emission was as suspected, and the ground temperature readings essentially said it was business as usual, and an eruption was not expected. No unusual activity was detected.

But all of that changed at 8:32 AM, when a magnitude 5.1 earthquake hit, triggering part of the volcano to slide. What happened next became the largest landslide in recorded history, moving at up to 155 miles per hour. It covered an area of nearly 24 square miles.

Scientists quickly were able to reconstruct the motion of the landslide due to a series of images from photographer Gary Rosenquist, who was staying 11 miles away from the blast. Had he been 1 mile closer, he likely would have died.

The landslide exposed the magma in Mount St. Helen to a much lower pressure, causing the explosion. The blast consisted of very hot volcanic gas, ash and pumice, moving at 220 miles per hour initially, accelerating to 670 mph, potentially bypassing the speed of sound. 230 square miles of forrest was knocked down. The lateral blast itself lasted no longer than about 30 seconds... but the effects would be felt long after.


A direct quote from the Wikipedia page: "The May 18, 1980 event was the most deadly and economically destructive volcanic eruption in the history of the contiguous United States". The blast took with it 57 lives, 200 houses, 47 bridges, 15 miles of railway, 185 miles of highway, and thousands of animals. Indirect deaths occurred, too, including accidents due to lack of visibility and heart attacks from shoveling ash.

The volcano itself was reduced by about 1,280 feet, and left a crater about 1-2 miles wide and 2,100 feet deep.

Trees and forrest were damaged or destroyed en mass. Crops were destroyed. Up to 1,500 elk and 5,000 deer were killed, and an estimated 12 million salmon fingerlings died.

In all, the eruption released 24 megatons of thermal energy, which is about 1,600 times the size of the Hiroshima atomic bomb.

The death toll, most commonly quoted at 57, is disputed for a couple of reasons. There were 2 men reported missing, but in the aftermath, 2 men of the same names were located. However, since authorities were unable to determine who reported the 2 men missing, they couldn't confirm that they were the same men who were reported missing, so they are still listed as presumed dead. There are also 3 missing people who were not included as victims of the blast, who's families believe that they were killed in the blast. Because of these discrepancies, the death toll could range from 55-60.

Beyond the immediate effects of the blast, there were some major problems after. For instance, transportation, sewage disposal and water treatment systems had serious issues due to the ash, and visibility was greatly decreased, causing the closure of many highways and roads, some for weeks. Air travel also had to be interrupted because the ash continued to provide for poor visibility, leading to over 1,000 flight cancellations.

The ash also had to be removed, and there was an estimated 2,400,000 cubic yards, equalling about 900,000 tons that had to be removed. It took over 10 weeks and cost $2.2 million. The cost of the disaster in total was about $1.1 billion.

And there are still indirect costs of the eruption to account for. Unemployment skyrocketed, as well as stress and emotional problems. Mental health funding was requested to help with the sudden onslaught of mental health needs.

Tourism was also gravely effected, which is to be expected. But tourism didn't just slow near the eruption site, but elsewhere in Washington and Oregon that hadn't been affected by the eruption, with conventions and gatherings being cancelled due to fear.

The volcano has erupted again, a few times. There were 5 additional eruptions between May and October of 1980, and there were periods of activity through early 1990. The volcano is still active, and smaller eruptions have occurred into 2008, but with no loss of life or serious destruction.


While there isn't easily accessible information on all 57 victims, there is interesting information on a few of the people who died in the explosion.

Harry Randall Truman was seen as a "hero" in the weeks leading up to the explosion, because he refused to leave his home, despite desperate pleading and urging by officials. He said he would never leave his home in various colorful, expletive-ridden interviews with the press. His wife had died a few years earlier, and he lived alone in his lodge with 16 cats.

His home was hit by a mud and snow avalanche and completely covered, and his remains were never found. There is something to be said for refusing to leave your home, and also something to be said for doing something stupid that only puts you in danger and not others, but I can't help but believe he would be protesting wearing a mask to the grocery store if he were alive in 2020.

David A. Johnston was a volcanologist who was monitoring the site from an observation post that was thought to be relatively safe, but was ultimately destroyed in the explosion. His last known words were "Vancouver! Vancouver! This is it!" via radio transmission as the eruption happened, and then his signal blacked out. His remains were never found.

He saved many lives because he was outspoken about how dangerous the volcano could be before others shared the same concerns. He is credited with holding the death toll to "a few tens instead of hundreds or thousands", quoted the U.S. Geological Survey. An observatory built near where he was stationed was named after him. There is a very famous photo of Johnston sitting in a chair outside on the job, 13 hours before the explosion would kill him.

Reid Blackburn was a 27-year-old photojournalist who was documenting the lead-up to the eruption. He was camped out at a site about 8 miles away from the north side of the volcano when it erupted.

In what has to be one of the most terrifying deaths imaginable, Reid was able to get in his car to try to drive away before it was covered in superheated ash and gas.He was found in his car, buried. Film from his camera was not able to be developed.

The National Press Photographer's Foundation has created an annual $2,000 scholarship for young photographers in his name.

The volcano erupted 40 years ago today, and I can't help but mark the similarities between it and the current pandemic. Concerning, dangerous things had been happening for months, but as soon as things seemed to be even barely okay, people demanded restrictions be lifted. Scientists remained at the helm of the issue while some people refused to listen to their suggestions. And the people we needed during the time of crisis (volcanologists, scientists, photographers) risked, and gave, their lives for others. In times of chaos, you see some of the worst of humanity, but also, some of the very best.

And luckily, in this situation, the good people far outweighed the bad and they helped significantly lower a death toll that could have easily been tenfold.

Volcanoes are kind of terrifying to me, mostly because they're just a chaotic, eruptive disaster waiting to happen, and the last one happened 40 years ago today.




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