http://www.nrtoday.com/article/2010100229995The devastation following the earthquake in Haiti on Jan. 12 shocked many in Douglas County, but right here at home a similarly damaging earthquake is just waiting to happen.Lurking under the sea 50 miles off the Southern Oregon coast is a dangerous threat. Two pieces of the Earth's crust pushing against each other at an offshore fault will eventually cause an earthquake reaching a magnitude of 9.0 or higher that will rock Douglas County, according to experts, as well as the rest of the state.
The resulting shaking, which could last anywhere between four and 10 minutes, would result in tsunamis, flooding and landslides that would likely cause widespread devastation. Buildings, roads, highways and bridges throughout Douglas County would be damaged. Power, water and other utilities would be cut off. Communication with land lines, as well as cell phones, would be impossible.And this type of devastating earthquake could be due to strike Oregon. Geologists predict that such an earthquake happens about every 250 to 800 years. The last time such a huge earthquake hit Oregon was 310 years ago.“It's one of those things that geologists are fond of saying, ‘It's not a matter of if. It's a matter of when,' ” said Umpqua Community College geology instructor Jason Aase.
The chance of Oregon being hit by a major quake in the next 50 years, he said, is about 14 percent.“If you go to California, earthquakes happen all the time,” said Aase. “Here they don't happen so people aren't prepared for them. Certainly not a magnitude 8 or 9. That's huge.”The Haitian earthquake was a magnitude 7.0 and lasted about 40 seconds. At a magnitude of 9, the earthquake lurking in Oregon's future would be much more violent, said Aase. It would release roughly 900 times the amount of energy as the Haiti quake and last for minutes instead of seconds, he said. Government agencies were ill-equipped to handle the Haitian quake devastation. Many buildings would never have met the strict seismic standards required in the U.S.In Douglas County, those who would be called upon to help during a devastating earthquake say they have a disaster plan.
Measures include ensuring the availability of shelters for quake victims, running disaster drills and setting up special modes of communication so government agencies and other disaster responders can connect even if phone lines are down. The Cascadia Subduction ZoneEach day, more pressure builds up along the 700-mile-long Cascadia Subduction Zone, where the Juan de Fuca Plate meets the North American Plate underneath the Pacific Ocean.
Along the subduction zone, which stretches off the coast of southern British Colombia down to upper northern California, the two plates constantly push up against each other, causing the Juan de Fuca Plate to subduct, or sink, underneath the North American Plate. “It's trying to force its way underneath the North American Plate,” said Aase of the Juan de Fuca plate. Aase likens the process to compressing a yard stick on both sides. At first, it will just keep bending and bending, but at some point, the pressure will be too great and the stick will snap.“Eventually, the two plates are going to come together and it's going to release all this energy,” he said. Devastation
The resulting earthquake would have catastrophic, far-reaching effects, said James Roddey, earth sciences information officer for the Oregon Department of Geology and Mineral Industries. Roddey, who said he is often referred to as the “Prophet of Doom,” travels the state preaching to the public about the impending disaster, including a speech he gave at Roseburg High School last spring.“There would be substantial damage in Southern Oregon,” he said, adding that this part of Oregon is even more susceptible to damage because the Cascadia fault is about 25 miles closer to the coast than in the rest of Oregon.Douglas County's coastal communities would be the most vulnerable, he said. Towns such as Reedsport and Winchester Bay would be flooded by tsunami waves stretching more than 100 miles long and 30 to 70 feet tall, crashing into the coast repeatedly.
But areas farther inland, such as those along the Interstate 5 corridor, wouldn't be spared despite experiencing a lower magnitude of about 7.0, Roddey said.In Roseburg, for instance, older historic buildings in areas such as downtown, especially those built out of brick, would be destroyed. Homes and businesses near the South Umpqua River and on steep hills could be swept away by landslides. Bridges crossing the South Umpqua River, such as the Washington and Oak Street spans, would be in danger of collapsing. “A huge magnitude 9 earthquake is not going to shake violently. It's going to shake for a long time and that's how it does the damage,” said Roddey.Meanwhile, throughout Douglas County transportation would be extremely limited, causing family members to easily become isolated from each other.“The I-5 corridor would cease to exist,” said Roddey. Since the highway passes over so many waterways with bridges that aren't likely to withstand being shaken for so long, it would be basically impassable, he said.
An Oregon Department of Transportation report on the seismic vulnerability of Oregon state highway bridges, which came out last November, confirms Roddey's warning. “With the majority of state-owned bridges designed and built between 1950 and 1980, the state of Oregon would face a devastating post-earthquake situation if a major event occurred in the state,” the report states.According to the report, along with bridge collapses along Interstate 5, U.S. Highway 101 would be severely damaged. Additionally, all of the existing state highways connecting Highway 101 to I-5 would be impassible, which would effectively cut the coast off from the rest of Douglas County Emergency Response.
In anticipation of all these frightening scenarios, those who'd be called on to help with relief say they have plans in place to make disaster relief go as smoothly as possible.“The people in the field are going to do what they're trained to do,” said Wayne Stinson, who's in charge of the Emergency Management Division of the Douglas County Sheriff's Office. The difficult part will be coordinating relief efforts among various communities and agencies, he said.“The good thing is there's a lot of emergency services in most of the communities,” he said. “We've got back-up systems for a lot of critical components.”“But are we ready?” he added. “ No.”
The problem is it's near impossible to fully prepare for such a large earthquake, but he and others responsible for disaster response in Douglas County are doing their best to be ready for the worst, one step at a time, he said.“It definitely would be a collaboration of the community in the event of a disaster,” said Kathleen Nickel, a spokeswoman for Mercy Medical Center.
The hospital, like other agencies that would respond in a disaster, has created a disaster plan and participates in regular drills with other emergency responders to be prepared for the worst. Mercy, for, instance, has water stored and generators for power with fuel to last about a week, said Bob Dannenhoffer, vice president of clinical effectiveness and a member of the hospital safety committee. Stinson said the Emergency Management Division coordinates one or two disaster drills a year where a county emergency operation center is set up at the sheriff's office to coordinate disaster response.
Last year's exercise was a earthquake scenario, he said. One advantage of smaller, more rural communities of Douglas County, Stinson said, is a familiarity among emergency response agencies.“We all know each other,” he said. “Most of us know each other on a first name or occasional contact basis.”Along with anticipating working together with county emergency responders, the Douglas County Chapter of the American Red Cross has agreements with local churches, schools and community centers to create up to 75 disaster shelters throughout the county, said Red Cross volunteer George Roth, the local emergency services coordinator. To supply these shelters, they've stockpiled food, water, cots, blankets, clothes, toiletries and basic first aid supplies, he said.They've also set up plenty of ways to keep in touch with other shelters and agencies providing disaster relief, using radios that should work even when other modes of communication are down. These radios, he said, will also make it possible for families that have been separated to communicate with one another and send along a message that they're alive. The Red Cross can also set up a Web site, like the one created following Hurricane Katrina, to alert relatives living in other parts of the country that family members are all right. Roth is among about 40 or 50 people in the county that operate amateur radios that can also be used for communication following an earthquake.
The county has taken similar measures to ensure that disaster responders can communicate, said Stinson, but if those fail, communications may depend on amateur radio operators.
Among the greatest concerns is the threat of coastal Douglas County being cut off from the rest of the county, said Stinson. As a result, a special emergency management center would be set up at a Reedsport fire station to serve that part of the county, he said.
Personal responsibility -Ultimately, though, county disaster response experts say each person is responsible for their own safety and survival following a high-magnitude earthquake.
Stinson said he often preaches the importance of personal preparedness, because there's no way people will be able to rely on the government following such a large-scale disaster.Roth agrees.“If you have an event that renders a whole community in need of (emergency) services, you need to be prepared to take care of yourself,” he said.
Families should arrange a central meeting point if they are separated and stockpile enough food, water and other supplies to last for at least three days — two weeks in rural areas and along the coast, he said.“The important thing is for people to be aware that it can happen,” he said. “Make a kit and prepare as a family.”•
You can reach reporter Inka Bajandas at 541-957-4202 or by e-mail at
ibajandas@nrtoday.com.
This graphic shows the predicated path of the tsunami and the predicted wave heights. The areas in the red are estimated to be up to 100 cm in height, although the angle, local sea floor, and coastal terrain can affect how high the wave crests on the shore.
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