Seismic vulnerability leaves Southwest Portlanders quaking in their boots

by: CONNECTION PHOTO: VERN UYETAKE - Jim Nicks of the Portland Bureau of Development Services teaches a seismic strengthening class held at the Multnomah Arts Center March 21.In February 2010, a magnitude 8.8 earthquake struck Chile. In March 2011, a magnitude 9.0 earthquake rocked Japan. And evidence suggests that at some point in the future, a similar quake will rock Portland — in fact, it should have already.

Oregon sits on the Cascadia Subduction Zone, a giant fault where the ocean floor and the land come together come together, the ocean floor beneath the land. According to the Oregon Department of Geology and Mineral Industries, “Where frictional resistance on the fault is greater than the stress across the fault, the rocks are ‘locked’ together. Stored energy is eventually released in an earthquake when frictional resistance is overcome.”

by: CONNECTION PHOTO: VERN UYETAKE - Heather Rosenwinkel learns to retrofit her home at a seismic strengthening class at the Multnomah Arts Center March 21. The Cascadia subduction zone gives way at least every 238 years. The last subduction zone earthquake occurred Jan. 26, 1700 — which means that the next quake is long overdue.

Because the Cascadia subduction zone is nearly identical to the one that caused the devastating earthquake two years ago in Japan, scientists have believed for some time that Oregon’s next quake will be of equal magnitude,

Last month, the Oregon Seismic Safety Policy Advisory Commission reported to Oregon’s 77th Legislative Assembly the Oregon Resilience Plan, a landmark report endorsed by Gov. John Kitzhaber. The report confirms that Oregon is vulnerable to a magnitude 9.0 earthquake and notes that when that quake strikes, the damage to cities located in Oregon’s Valley impact zone, including Portland, will be moderate.

Long before the official word came down from Salem, the City of Portland has been operating under the notion that it is only a matter of time before such a quake strikes. Preparing for that earthquake has primarily been the task of the Portland Bureau of Emergency Management (PBEM), which was previously housed under Portland Fire & Rescue prior to becoming a stand-alone bureau about a decade ago.

“One of the things that we’re required to do is a natural hazard risk assessment, and since we know that earthquakes are our biggest natural hazard risk, we’ve really been working on this issue from day one,” said Portland Bureau of Emergency Management (PBEM) Director Carmen Merlo. “Even back when we were in the fire bureau, we’ve known that preparing for an earthquake is probably our biggest challenge and our most significant risk.”

Southwest Portland is no exception.

The Cascadia subduction zone wasn’t recognized as an active fault until the 1980s, and as a result, Portland homes built before the 1970s are vulnerable to structural failure.

“One of the things that we see ... after earthquakes is landslides, and we have a lot of homes in Southwest Portland that are built on very steep hills or that are on steep slopes,” Merlo said. “We’ll have some homes (built) on the top of the hill that will maybe be down at the bottom of the hill.”

Betsy Shand, chairwoman of the Southwest Neighborhoods, Inc. Public Safety Committee, agrees.

“The West Hills and areas built on loose soil … would be especially unstable,” she said, “and ”riverfront areas … will be subject to liquefaction.”

In addition to havoc wrought in Southwest neighborhoods such as Hillsdale, Homestead, the Southwest Hills Residential League and South Portland, destruction in other parts of the city could have have an indirect but equally detrimental impact on Southwest as well.

“If the earthquake happens during a business workday, we’ll have a lot of challenges because of the concentration of people that are downtown, so we’re going to be less likely to respond to the few homes way, way out in Southwest when we’ve got a heavy, dense population in need here in downtown,” Merlo said.

Even if emergency workers could be spared to go out and provide aid in neighborhoods on the edge of Southwest such as Arnold Creek and Far Southwest, they may encounter other roadblocks.

“There’s very difficult parts to reach in Southwest,” Merlo said. “There’s narrow roads, and ways to access parts of Southwest will be compromised.”

“The quake would cause significant damage to our infrastructure, homes, businesses and roads,” Shand said. “Our ability to communicate would be altered.”

With that in mind, the PBEM has been hard at work teaching Portlanders to help themselves in an emergency situation, through NETs, Neighborhood Emergency Teams, Portland residents trained by PBEM and Portland Fire & Rescue to provide emergency disaster assistance within their own neighborhoods.

Becoming a NET member entails filling out a registration form, completing online basic training and passing a quiz, signing up for and completing 21 hours of in-person basic NET training and completing a background check.

Each of the Southwest's 17 neighborhoods is served by NETs, but, Merlo said, “Some have more than others. South Burlingame probably has two NETs … but other neighborhoods like Multnomah, we’ve got 20, so it really varies depending on the neighborhood.”by: CONNECTION PHOTO: VERN UYETAKE - Jim Nicks of the Bureau of Development Services shows Southwest Portlanders an anchor screw, used to protect homes from earthquakes.

Citywide, “We’ve probably trained over 1,700 people,” Merlo said. “That doesn’t mean that all of them are active NETs. I could have taken the class just because I wanted to be better prepared for myself and my family.”

And even if all them were active, Merlo added, 1,700 people “is not nearly enough for a community the size of Portland. We’d like to see tens of thousands of people trained.”

While hoping to see an uptick in citizens interested in becoming NET-trained, the PBEM is aware that a magnitude 9.0 earthquake "will be a very disruptive event," Merlo said, impairing telecommunications and suspending wastewater control for weeks and even months thereafter. With that in mind, it has established 48 Basic Earthquake Emergency Communication Nodes (BEECNs), temporary radio communications sites staffed by at least one person after a major earthquake where citizens can report severe damage or injury or seek emergency assistance when phones are down.

There are 10 BEECN sites in the suburban Southwest area. However, the PBEM website notes, “It’s best if you can stay at home and remain self-sufficient until help arrives.”

All in all, Merlo said, “During an earthquake, our ability to respond everywhere is going to be severely limited, so the more people can do to prepare themselves and their family before an emergency happens, the better off they’ll be.”

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