Saturday, January 28, 2006
TV Show gives Mount Rainier's full potential!
The 30-minute show on Comcast Channel 78, called “It Could Happen Tomorrow,” depicts what would happen to the town of Orting and surrounding communities if a huge chunk of Mount Rainier suddenly collapsed, sending a slurry of mud, rock, snow and ice racing through the Puyallup Valley.
“Entire communities will disappear from the earth,” the narrator pronounces in his solemn yet dramatic voice.The fact of the matter is: The narrator is right. Eruptions and earthquakes at the Cascade Mountain range’s aging, iconic volcano have triggered these types of mud flows, known as lahars, before. What is now Orting, population 4,400, was built atop a 30-foot-deep piece of Mount Rainier that flowed down the river valley 300 years ago.In fact, the latest assessment by the U.S. Geological Survey places the risk of a catastrophic lahar from Mount Rainier at 0.1 percent to 0.2 percent per year, noted Tom Pierson, a USGS geologist stationed at the Cascades Volcano Observatory in Vancouver, Wash. Pierson appears on camera in the show.
The Weather Channel narrator takes that data and extrapolates it to say that someone who lives his entire life in Orting has a 1 in 7 chance of experiencing a lethal lahar.“That’s not an unreasonable number,” Pierson said Thursday. Incidentally, Pierson hasn’t seen an advance copy of the show, and he doesn’t get the Weather Channel. I offered to lend him my advance screening copy, if he can’t get his hands on one.
Giving the chance for a lahar a number is a little dicey in the first place, Pierson said, because scientists are working on a pretty small set of data.The show makes two very accurate and relevant points when examining the risk posed by Mount Rainier.First of all, as Pierson points out in his Weather Channel interview, Mount Rainier is covered by 1 cubic mile of snow and ice, more than all of the other Cascade peaks combined. That’s a lot of material available to bury a river valley.
Secondly, despite Mount Rainier’s beauty, it is 628,000 years old. Mount St. Helens, the relative newcomer on the block, is 40,000 to 50,000 years old. With age comes decay, and with decay comes a greater chance of a sector collapse of the volcano, even without the aid of an earthquake or eruption.Incidentally, the Weather Channel show relies on a lot of footage from the 1980 Mount St. Helens eruption to illustrate the dangers of Mount Rainier. OK, fair enough.
And in the case of Mount Rainier, as many as 100,000 people are living and working directly on top of mud flows which, if they happened today, would bury them if they didn’t scurry out of harm’s way.Folks in Orting would have about 40 minutes to bolt for higher ground, once the mud flow sensors mounted on the flanks of Mount Rainier triggered sirens in town.To reach higher ground, residents would have to cross a bridge — either one across the Carbon River or one over the Puyallup River.
Good luck getting everybody out of town.I have a confession to make. I didn’t learn much from the show.I’ve written about most of the information presented on the geologic hazards of Mount Rainier several times before in The Olympian.But the simulated footage of a lahar plowing through Orting was new to me.The show is informative, visually drawing in the viewer.
And, if you’re a newcomer to Puget Sound, there’s a lot to learn from it. Just ask Barb Digman, an Olympia-based clinical psychologist who moved here about 18 months ago and watched the advance screening with me to provide a fresh perspective.
After viewing this nightmare waiting to happen, she was amazed by how much snow and ice sits on Mount Rainier and how this seeming fortress of a volcano actually is crumbly and vulnerable to collapse.“My curiosity is piqued,” she said. “I want to learn more about Mount Rainier.”By the way, she also ruled out Orting as a place to live.“Why put yourself in an area that’s had these kinds of disasters before?” she asked.