About the Anniversary of Mt. St. Helens Eruption

DESCRIPTION:

On May 18, 1980, Mount St. Helens, a volcano in the Cascade Mountain range of the northwestern region of the United States, erupted, unleashing 24 megatons of thermal energy, removing the north side and shrinking the mountain's height by about 1,300 feet (400 m). It left a crater one by two-mile (1.6 X 3.2 km) gash in its wake.

The blast cloud enveloped the 17 miles north of the volcano. The landslide traveled about 14 miles west down to the North Fork of the Toutle River, where debris eventually wiped out the bridge on Interstate 5, the main north-south highway between Mexico and Canada in the United States.

Prevailing winds blew 520 million tons of ash east across the United States and caused complete darkness in Spokane, Washington, 250 miles from the volcano. Fifty-seven people died due to the eruption, in addition to over 7000 large game animals and around 12 million salmon.

The plinian eruption was in the same category as the infamous Mount Vesuvius eruption of 79 AD and ranked five on the Volcanic Explosivity Index. That index measures volcanos on a scale of 1-7. Seven would match the volcanic eruption 600,000 years ago that created the Yellowstone Caldera when over 100 cubed kilometers of earth were extracted by its force. By contrast, Mount Saint Helens blew out 2.79 cubed kilometers.

Experiencing the eruption

My family had just moved to Portland, Oregon, from Silicon Valley in January 1980 when rumblings began registering on the mountain in February and March. We traded earthquakes for volcanos, it seemed. On May 18, the mountain completely exploded. I don't recall hearing it or seeing anything, but you could see the cloud from Seattle, Washington, and Portland, Oregon.

That first significant explosion blew east rather than west where we lived. In the weeks following, one could follow the ash cloud spread in a large funnel shape from its origin, over the Rockies and into the Dakotas. The cloud was so large and dense in ash visible from outer space.

I remember my father loading us in the FIAT and taking us to the top of Skyline Drive, which runs along the hills separating where we lived from the city of Portland and the Willamette River. It seemed to go on and on, as high as the eye could see. The mountain seemed to cough up billow after billow of gas and hot ash. We'd never seen anything like it and would later discover that the blast removed the mountaintop.

Over the next several months, the mountain continued to erupt, with the wind not always in our favor. One particular Saturday, my parents held a garage sale. When we walked outside, it looked like it was snowing. It wasn't. It was ash, falling from the sky and covering it in several inches of grey, flaky dusk.

That dust got into everything, turning into a thick paste when it rained. We had to walk around for days with monkey masks (my word at the time for the masks so standard now after COVID-19), which as a young teen, I detested. But the air was too thick to breathe. One of the aspects I remember fondly was when my father allowed me to help him take apart the engine of the FIAT and clean it. Every part of the car was caked in ash dust. Thank heaven Rosey's engine wasn't as complicated as today's. She had a manual choke, manual clutch, and no radio. It was a great learning experience and a tremendous father-daughter project. Little did I know that car would be mine in a few years.

For those of us who witnessed Mount Saint Helens and her eruption, it is something we'll never forget. For us, far away, it was curiosity. For those close, fifty-seven people died, most from inhaling scalding ash.

Round about the 25th anniversary, I found myself in Oregon again. Now in my thirties, I drove my car up to the mountain, which had reopened. The forest was beginning to come back. Animals had returned, and for a moment, it was nearly impossible to believe the event had ever happened. Then I glanced skyward toward the crater where a rounded dome once stood, and the reality returned.

Oh yes, now, I remember. I remember it well.