Coastal Areas Prepare For The Other 'Big One'

California has just completed a landmark effort to assess the state's worst-case tsunami danger. Now emergency response officials, and even some planners, are considering how to keep the state's coastal populations safe.

1 minute read

March 13, 2010, 7:00 AM PST

By Josh Stephens @jrstephens310


"Approximating maximum inundation for a worst-case scenario tsunami, the line washes over all of Newport Bay and Marina del Rey, wipes out parts of downtown Santa Cruz, and makes half of Seal Beach disappear. Some of the state's most fabled real estate from La Jolla to Malibu to Montecito would wash out with the tide. It would yet again pummel Crescent City, itself the victim of the nation's most destructive and deadly recorded tsunami, a 20-foot wave that struck on Good Friday, 1964."

"The maps assign to the tsunami threat a visual element that is absent from the prediction of earthquakes. Contrary to this discomfiting picture, however, researchers and state officials alike caution that the maps' projections in no way mean that the state's coastal communities and nearly 1 million coastal residents should permanently decamp for higher ground."

"Memories of the 2004 south Asian tsunami -- and of the statewide warnings that were sounded after the February 25 Chilean earthquake -- make clear the destructive threat of tsunamis. The maps were prompted by recommendations in a 2005 risk assessment report published by the state Seismic Safety Commission. That report, which was prompted by the south Asian event, noted that roughly 80 tsunamis have struck California over the past 150 years and that two of them were destructive."

Thanks to Josh Stephens

Wednesday, March 10, 2010 in California Planning & Development Report

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