Welcome to Big Sky (Earthquake) Country: Drop, Cover, and Hold On!

Wednesday morning, an estimated 150-thousand Montanans will dive under their desks, for the Great Montana ShakeOut, the state’s annual earthquake drill. The fact that Montana has earthquake drills at all probably comes as a surprise to some, according to Michael Stickney, director of the state’s Earthquake Studies Office at Montana Tech in Butte.

“When I give the occasional lecture and talk about studying earthquakes in Montana, the reaction from many people is ‘I thought only in California had earthquakes…'" Stickney says.

“We do see on average 4 to 5 minor earthquakes each day somewhere around the state. Only sensitive seismographs pick them up. People wouldn’t notice them.”

If most Montanans don’t worry about earthquakes today, it’s probably because the last big one was over fifty years ago, but quakes have hit Montana hard, especially during the twentieth century.

The best known of these, a swarm of earthquakes in October 1935, nearly destroyed the capital city. A newsreel from that era recounts the damage: “Helena Montana smashed by earthquakes...one of the year’s worst disasters! Over a thousand shocks in three months! Hundreds left homeless, many dead! The plucky city emerges undaunted from the ruins!”

Pam Attardo, Helena’s Heritage Preservation Officer, says collapsing brick buildings lead to multiple deaths.

“In the last earthquake four people were killed,” she said. “Two of them because they were hit by falling debris and two gentlemen were actually trying to take down bricks off a stack of the Kessler brewery. They came down in a shower of bricks and mortar and were basically buried”

An eyewitness to the largest of the 1935 quakes was Helen Piper, principal of a Helena boarding school, who described the temblor in a letter

“...there came a crash and with the crash the weaving of the building. ...Truly, the walls went in and out in a most indescribable way. ...Plastering fell and the lights went off. The walls went out on the fifth floor. ...Radiators came down. ... I know you will all be quite proud of our school management when I tell you that in six minutes time in a dark house the children were all taken out and not one child cried.”

The people who survived the 1935 quakes carried the memory with them for the rest of their lives. Pam Attardo says many of Helena’s buildings still carry the scars of those quakes, as well.

“The top of the Securities building used to be a beautiful little bell shaped dome. That came down. The clock tower on the courthouse came down. The jail had a crenellated tower and additional roof and decoration and those are gone, so Helena used to be a lot more vertical than it is now, is I guess a good way to put it.” Attardo said.

As damaging as the 1935 Helena earthquakes were, Michael Stickney says, they weren’t even the largest to hit the state:

“The granddaddy of them all was the 1959 Hebgen Lake earthquake” Stickney said. “(It was) a magnitude 7.3, killed 29 people, did extensive damage to roads and the Hebgen Dam in an area with that has a very low permanent population.”

Stickney says there’s no telling whether Montana is overdue for another damaging quake.

“We do not have enough historical perspective to know if back then was unusually active or the other alternative is that we’re in an earthquake drought now.”

The Great Montana Shake Out aims to get the state ready for the next big one, whenever it happens. At precisely 10:21 Wednesday morning, in schools and colleges, offices and homes across the state, Montanans will practice what to do when an earthquake hits. The basic instruction is, “drop, cover, and hold on” underneath a sturdy desk or table for at least sixty seconds. And while you’re holding on, look around - do a quick inventory of all the things that could cause damage or injury in an earthquake.