Mount Rainier: The sleeping giant

06:11 PM PDT on Tuesday, May 17, 2005

By ELLEN LIANG / KING5.com and GLENN FARLEY / KING 5 News

The USGS recently concluded as part of its survey on volcano hazards, that Rainier is the third most dangerous volcano in the United States. One reason is that it's so close to so many people.

“We would be concerned on Mount Rainier, even with the heating-up process, because even the little kind of deformation we're seeing at the dome crater floor could be enough to break off a chunk of mountain and then, combined with water, could produce lahar debris flow that would threaten downstream communities," said Dr. Bill Steele, University of Washington seismologist.

Scientists say there is more ice and snow on the top of Mt. Rainier than on all the other Cascade volcanos combined. It would not take an explosive 1980-style St. Helens eruption to create a disaster for people downstream of Mount Rainier, even if just part of the huge ice cap were to melt.

Pierce County Emergency Management is constantly challenging its readiness for a mass evacuation with 14 lahar warning sirens telling residents to head for higher ground.

“There are certain kinds of these biblical disasters where the only thing you can do is get out of harm's way, there's no other alternative,” said Steve Bailey of Pierce County Emergency Management.

When it does melt, scientists say the flood of mud and water, or lahar, that will come down from Rainier will be even thicker than what came down from St. Helens.

But it's in the path of the Puyallup Glacier, where homes are being built and sold. It’s an opportunity for people to buy an affordable house in an otherwise expensive Puget Sound housing market.

And communities, including Orting, are expanding even though the volcano threat is clearly posted on evacuation signs. The lahar warning siren in the middle of town.

“There's an old saying, ‘Never be afraid to leave your luggage,’” said John Carmichael, a Sumner resident. “Get yourself out, leave the rest of it. Come back and dig it out. If it's not, you start over. But get your family out. That's the key.”

John and Shirley Carmichael live in nearby Sumner. They're accutely aware that there is a risk and have hosted a neighborhood emergency preparedness meeting in their home.

“It may not happen for 100 years, we don't know that,” said Shirley Carmichael. “But if we're prepared, we'll feel a lot safer about it.”

So what are the chances? A major lahar on Mt. Rainier happens about once every 500 to 1000 years. And it's been about 550 years since the last one. That means the window is open. It could be hundreds of years before it happens again. Or it could be tomorrow.

“Because of Mt. St. Helens, Mt. Rainier is regarded much more as a volcano, capable of producing erruptions and very serious hazards,” said Willie Scott of the USGS.

Three years ago Mount Rainier experienced a glacial outburst, a major release of debris that triggered the emergency response system. Water and boulders came rushing down the Nisqually River.

Now, every three months, emergency management officials and representatives from cities and school districts meet at Mt. Rainier National Park to work on their evacuation plans and consider the latest science. But they still don’t have all the answers.

“We have tried to marry the public safety policy and the scientific information as best we can to say the Puyallup is our issue, our big public safety issue,” said Bailey.

But how far do these mud flows travel? According to the USGS, over the last 5,000 years, there's evidence through Ashford, Elbe, Orting, Puyallup, Auburn, Commencement Bay, Kent and even Renton.

“It's much more likely that that kind of event will follow some sort of warning,” Scott said.

The Puyallup valley has the most people, but would also get the most warning from lahar monitors on the mountain. It would probably take 40 minutes in Orting for people to follow evacuation signs and get to higher ground.

Many schools in Orting are situated right along the river and with only one road going in an out of town, students are the ones who will need another place to go. One idea is to build a bridge along the Puyallup and Carbon rivers.

Still, Mount Rainier isn't scaring anyone out of town. Roughly 30,000 Puyallup River Valley residents are in direct danger in a volcanic eruption, along with more than 100,000 people living in Mount Rainier's six other valleys. The towns at risk would be Orting, Sumner, Ashford, Elbe, Packwood, Randle, Greenwater and parts of Puyallup. The flow could also affect parts of Tacoma, Buckley and Enumclaw.

In Ashford last year, an anonomous donor supplied NOAA weather radios that will warn residents of an impending lahar.

Many other volcanoes have little or no regular monitoring and need to be watched for potential eruptions, a recent report from the U.S. Geological Survey warned. These include nine volcanoes in the Cascade Range -- Rainier, Hood, Shasta, South Sister, Lassen, Crater Lake, Baker, Glacier Peak and Newberry.

Although earthquakes at Mount Rainier are monitored by the University of Washington and the USGS, and their shapes are measured regularly by staff of the USGS's Cascades Volcano Observatory in Vancouver, Wash., it's not enough, said John Ewert of the USGS.

"For the potential threat it represents, Rainier is undermonitored," said Ewert said. "When we consider, for instance, that Rainier is very large and very high so you need a helicopter to put additional instrumentation there and some areas are inaccessible in winter...With volcanoes that we believe pose a high level of threat, we don't want to be in a position to know something is going on and putting (monitoring) people at risk."

Volcanic eruptions also pose a hazard to aviation because any plane flying through volcanic ash can experience engine failure.

In the Cascades, the volcanoes that pose the most risk are those with the most snow and ice -- Baker, Glacier Peak, Rainier, Shasta and Hood.

"They rate very highly in our scheme, they all have a history of eruptions and lahars that have traveled some distance," Ewert said. "With snow and ice-clad volcanoes, lahars can travel 50 miles or more. In the Cascades we have large river valleys whose head waters are by the volcanoes and lahars can travel long distances at high speeds.

"We want to provide the best early warning we can, and to do that we need to have in place apppropriate monitoring for those kinds of volcanoes."