Scientists at the time were in a dispute when it came to volcanos. The old school guys believed volcanoes just woke up from time to time, spewed a little lava and ash then went dormant for a few hundred years, there were exceptions but they were rare. The younger guys were a different breed, they were pushing new, wild ideas that volcanic eruptions could be sudden and violent and cause mass destruction. The old guys didn’t accept this but the younger guys kept pushing.
The young guys said, look at Yellowstone, the whole park is a caldera where a super volcano erupted one day and blew out everything in a sudden, violent eruption about 200,000 years ago. The old crowd said their time line was correct but the things we see today are simply the result of wind, rain and time erosion. Period.
And so their arguments went. Then in March 1980 a previously active volcano in southern Washington began rumbling. It had been quiet for over a hundred years but was waking up. There were quakes, a few small eruptions, some lava flow and steam venting but nothing to write home about, so the old boys said.
The quakes became more frequent and stronger, the venting and lava flows more often and stronger. At the end of the first week in May a mile long crack opened across the top of the mountain and it began venting steam, lava and ash. The second week in May saw a lava dome develop that was growing over nine feet every day. The young volcanologists said this mountain is going to erupt soon and it is going to be a big one. Still the good ol boys said wait and see.
In conclusion, no one had a clue what to expect or what to do because so little was actually known about volcanos at that time.
Then on May 18, 1980 at about 8:30 in the morning a massive landslide let go and slid down on the north face of mountain and almost instantly afterward a massive explosion erupted sending an ash and smoke plume over 14 miles up in the clear Washington sky, Mt Saint Helens had come to life.
Old Harry Truman owned and operated Spirit Lake Lodge at the base of Mt Saint Helens and had been there for decades. The sheriff’s department had told Harry to evacuate but he said no. He didn’t think there was any danger, the mountain had never caused much damage, so Harry was staying with his dog by his side. Shortly after the eruption the landslide hit Spirit Lake and caused the water in the lake to slosh over 700 feet up the other side of the valley. The debris from the land slide left Ol’ Harry and his dog over 300’ below the new surface.
David Johnston was a USGS volcanologist, from the new school. He was camped in his camper on a heavily forested ridge about five miles almost directly north of Mount Saint Helens doing observations. Several of Johnston’s associates had told him it was time for him to evacuate. He said not yet, he thought he had several more days to observe the mountain safely. When the mountain erupted it blew every tree off the ridge where Johnston was camped, it blew off all the soil and left the ridge completely sand blasted and bare. It remains so today. No trace was ever found of Johnston but a few pieces of his camper were found several miles away in 1976. The ridge was named in honor of Johnston and is now called Johnston Ridge. He should have been awake and working the morning of the eruption, making his observations and taking notes. If so, he saw the huge blast from the mountain come directly at him at almost the speed of sound. So he had about 20 seconds to think about the conclusions he had made about how safe the mountain was and to ponder why the hell he wanted to become a volcanologist instead of selling shoes at JC Penny.
Within just a few seconds 1,300 feet had been blown off the top of Mount Saint Helens, 2/3 of a cubic mile of rock was gone out of and from the top of the mountain.
70% of the snow and glaciers were also gone, blown by the blast or melted by the 600 degree super heated winds that caused a massive mud flow. The mud flow carrying rocks, trees and anything else that got in its path traveled down the steep slopes of the mountain at almost 80 mph then slowed to 35-40 mph as it reached more level ground. The Toutle (toot-le) River is the river we all saw on television that carried all that mud flow with trees, trucks, houses and bridges. When the mud flow finally reached the Columbia River, 55 miles down stream it caused the depth of the river at that point to go from over 40’ to 14’. The mountain exploded north but the natural flow from the mountain was west and south.
57 people died that morning, thousands of animals in the area died. 234 square miles of mature forest was blown down. Not a single tree was found within the blast zone of about 6/10 of a mile. The heat-kill zone extended 15-18 miles. The blow down zone extended 6-15 miles. The super heated winds blew down tens of thousands of trees and stripped most of their branches and bark.
The landslide and eruption from Mt Saint Helens filled in 14 miles of the valley below the mountain. When the slide finally stopped, water oozed out for weeks as the debris settled, like squeezing a wet sponge from the bottom. Thousands of people were affected by the Mt Saint Helens eruption, people were displaced, businesses were gone, jobs were no more. Just think of how the logging and forest businesses were affected.
One of the strange things reported by several survivors was the explosion of Mt Saint Helens made no sound. The people that witnessed the eruption up close saw the explosion but heard nothing. Scientists said it wasn’t until the blast hit the stratosphere and bounced back to earth did people near the eruption hear it. Don’t understand that one except they may have been to frightened to remember hearing it..
43 years after the eruption issues are still being worked on. Today the Toutle River drops many times more debris into the Columbia than it did prior to the eruption. Dredging is required regularly where none was required before the eruption.The landscape is forever changed. But life is returning, ground plants and trees are slowly growing back. As more plants grow back the animals are returning.When things got organized after the eruption the decision was made to salvage as many of the blown down trees as possible, over 600 of the blown down trees were were taken off the mountain. Seven days a week, for months and months and months.
In the Mount Saint Helens Museum there is a wall about 10’ high and 40’ long. The background consists of severl aerial photos spliced together to make a single landscape photo that covers the entire wall. You don’t notice it at first because it is a black and white photo and there are historical information notices attached to the wall. Then you see a sign that says take a few steps back and take in the wall photo. When you do it is amazing. From wall to wall, floor to ceiling all you see is blown down trees, thousands upon thousands. Can’t even begin to comprehend the power it took to cause this amount of destruction.
And by the way, the old Volcanologists are retired, the new, young guns are running the show today and teaching the even newer generations what they have learned what to expect and what to do about volcanic eruptions, because it will happen again. Mt Saint Helens is still grumbling today and the younger guys say it is wanting to build itself back. There are three “hot” zones in the mountain even today. Guess she didn’t say everything she had to say back in 1980.
They’re doing great work. If you are ever in the area and find a clear day this site is a must see. There are now three observation locations that give vastly different views. Johnston Ridge Learning Center is the nearest and directly in front of the blown out mountain but it was closed the day we were there because a mud slide had covered the highway. About a dozen people had to be evacuated & their cars are still in the learning center parking lot. It will be closed into 2024. If you like to be awed, this is one good place to go.
Later.
-Tom