The catastrophic 8.9 earthquake in Japan is a wake up call for residents of the Cascadia Subduction Zone. Author Betsy Mason, in This Day in Tech reports that an earthquake, with a magnitude of 9.0, took place in 1700 in the Pacific Northwest Subduction Zone. The quake triggered a wave of Tsunami all the way to Japan.
Mason warns:
"The Cascadia Subduction Zone is still active and will generate more major earthquakes in the future. Scientists have found that at least seven earthquakes around magnitude 9 have occurred over the last 3,500 years, an average of one every 500 years. But recent research has shown that many magnitude 8 quakes have shaken the area in the intervening years, bringing the average time between quakes down to 270 years.
Because there hasn’t been a major earthquake in the Cascadia subduction zone for 300 years, many people who live in the area are unaware of the danger or unprepared for a quake. And many buildings in cities on and near the coast, such as Portland, have not been retrofitted to survive a major jolt."Another danger for communities located along inland waters is an earthquake triggered landslide that creates a Tsunami in a lake or bay. For example, an earthquake generated landslide created a 1,700 foot wave in Lituya Bay on July 9, 1958.
Below, is a diagram from Department of Ecology reporting slope stability around Bellingham Bay. (This diagram can be accessed on page 19 (Appendix 6, Section 6.2) of the Whatcom County Hazard Identification document link posted below the diagram.
Link to 2010 Whatcom Ready Documents: Whatcom County Hazard Information and Vulnerability Analysis which describes potential levels of damage from earthquakes and other natural disasters, (Seiches &Tsunamis), right here in Whatcom County. Risk critical to limited.
* Note for Dave Onkels - please review Table 1 on page 7, for potential hazardous chemical releases. Our risk is critical.
Note for Latte Republic readers: over ten billion pounds of hazardous materials are shipped, stored, processed, or manufactured in, or through, Whatcom County each year. A catastrophic event, such as an earthquake could result in major risk from hazardous chemicals to Whatcom residents. (Pg. 15 of WCHIVA).
Extra credit question: How many of the chemical manufacturing facilities are located adjacent to coastal waterways? Shipping? Storage? Now you're catching on.
The moral of the story. No one can predict when or where the big one will hit. But we can take steps, through careful land use planning and emergency preparation to minimize injuries, deaths and property damage.
The lives we save may be our own...
Additional articles and research
The Smithsonian
The Pacific Northwest Seismic Network
Link to 2005 DNR Bellingham Bay Tsunamis Map (does not account for possible wave created by slope failures).
Link to conversion chart meters to feet (5 meters equals 16.40 feet)
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