The 1980 Eruption of Mt. St. Helens

At 3:47 PM, March 20, 1980 a 4.1 magnitude earthquake as measured by the Richter scale signaled the awakening of 9,677 foot Mt. St. Helens from a 123 year slumber. It raised no particular red flags as it was just another minor earthquake in the vicinity of St. Helens, a volcano in the Southern Cascades of Washington State. St. Helens last series of eruptions occurred over a 15 year period from 1842 to 1857 but had remained quiescent for the last 123 years.
Avalanche warnings began to be posted around the mountain as the quakes continued; by Sunday, March 23rd the quakes became even more numerous with the number of quakes increasing to about 40 per hour by Monday afternoon. At this point geologists began to think seriously about the possibility of an eruption occurring. It soon became more than a possibility. At 12:36 PM, March 27 as an explosion sent steam and ash 17,000 feet into the air and blasted a 200 x 250 foot vent just north of the summit. As the mountain continued to spew rock, ash and steam, by April 6th, the vent became a 1,200 by 1,700 foot crater. 
On April 8, U. S. Geologic Survey spokesman Don Mullineaux would point out that the volcano’s actions so far, “are very minor compared to what the volcano has done in the past. It is in a stable mode of eruption. It is still a minor eruption”.
As the mountain seemed to take a breather, seismic activity slowed and some restrictions around the mountain were lifted. By April 30th geologists began to take serious note of the growing bulge on the north side of the volcano. May 7, the bulge continues to expand but with another eruption of steam and ash and seismic activity reaching 5.0 on the Richter scale prompts the governor to order a closure and evacuation of areas around the mountain. May 12, another 5.0 earthquake plus the ominous growing bulge prompts landslide warnings to be issued to scientific teams on the mountain.
Sunday, May 18, 1980, 8:32 AM, it started as a landslide of epic proportions, then the pent up energy exploded across the valleys and lower ridges in a raging cloud of ash, rock and trees that were either uprooted or snapped like matchsticks. In a lateral blast the energy wave leveled trees up to twelve miles away. Thirteen hundred feet of the mountains summit was blown away; the energy released in the blast was 1,600 times more powerful than the bomb dropped on Nagasaki.
The glaciers on the mountains flanks and the waters of Spirit Lake mixed with this concoction and hurtled down the Toutle River as a huge wall of mud, ice and debris. It swept down the river taking everything in its path, 200 homes, 47 bridges, 15 miles of rail road, 185 miles of highways destroyed. A suffocating black cloud of ash enveloped campgrounds in the area stranding campers in the maelstrom. 57 people would lose their lives that day. 
The huge debris flow down the Toutle River caused the closure of interstate 90 at Castle Rock, Washington. The debris would hamper shipping on the Columbia River and force dredging operations as the channels became loaded with silt, sand and rock.
After the initial blast the volcano sent an ash plume 63,000 feet into upper air currents that took the ash in a northeasterly direction turning day into night as far away as Missoula, Montana. Interstate 90 would be closed due to poor visibility from the Cascade crest to Spokane, Washington. Poor visibility would force spotty road closures as far as western Montana.
Short after 8:30 that morning I was puttering around outside and noticed this wicked looking thunderstorm forming over the Cascades. Growing faster than any I had ever seen, lightning in its crown. I then realized the cloud was racing towards me. I hurriedly tried to take some photos when what we first thought were rain drops but turned out to be ash began to fall. It was then we realized that St. Helens had erupted.
The ash fall would come in bands at first, light and then heavy but as the day bore on the ash falls got heavier; as the ash fall got heavier the day became darker. At about 12:30 street lights began to come on as a very heavy band came across our neighborhood. They went off about an hour and a half later.
Sometime in the afternoon I began to hear small creaks and groans as the roof began to be strained by the weight of the ash. I quickly grabbed the push broom and began to push the ash into the flower beds. It saved the roof but ruined the flower beds for the year. The air that day smelled faintly of sulphur, it would get dim then light again leaving an eerie feeling.

The roof of the water company’s sistern was in danger of collapsing; volunteers donated time to shovel the roof clear. Volunteers helped elderly people shovel off roofs and car ports, washed cars, cleared sidewalks and piled the ash in the street per city instructions.
Volcanic ash works its way into anything and everything that moves. Air breathing engines suffered from ingesting the gritty stuff. We looked upon it as a scourge that summer as the dust would hang in the air for a long time when roiled. We had some soft showers in mid-June and the Lord blessed us with a cool and windless summer. As time wears on the scourge has become a God send in disguise. It enriched the soil with trace minerals and neutralized toxins that had built up in the soil as a result of fertilizer and weed killer applications.

I toured the blast zone two years after the eruption, the devastation was unimaginable. Old growth timber lying flat, all pointing away from the blast. As I got to the east side of the mountain the landscape was littered with pumice stones the size of tennis balls with little to no ash. Life had begun to return though as fireweed began to reclaim the landscape. Elk and deer began to find their way back into the area as vegetation slowly reclaims the land. It is truly miraculous to witness such devastation and yet see the natural world begin the job of reclamation.
I’m a crusty old codger with an old time religion inside me. To look at Mt. St. Helens as it was before, and to see it today I see God’s handiwork and feel rejuvenated by the sight. Amen

Walter Mow

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