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| 2014 Update To The USGS Seismic Risk Map |
Note: September is National Preparedness Month . Follow this year’s campaign on Twitter by searching for the #NatlPrep hash tag.
This month, I’ll be rerunning some edited and updated older preparedness essays, along with some new ones.
#13,528
Although Americans have been battered by Category 5 Hurricanes, 1000-year floods, devastating wildfires, crushing droughts, and super outbreaks of tornadoes over the past 3 decades, we've actually enjoyed a prolonged lull in major earthquake activity.
Major being quakes of 7.0 of greater magnitude, particularly in populated regions like Southern California and the Pacific Northwest.The result being that there is no one left alive today who remembers the great San Francisco Earthquake of 1906, and the far less damaging California quakes of the 70's, 80's and 90's are distant memories.
But as an article in The Conversation earlier this year by
Professor of Geophysics (Colorado State University) warns: California’s other drought: A major earthquake is overdue.
After near disasters with Hurricanes Camille and Betsy in the 1960s, `The Big One' is what emergency planners in New Orleans dubbed their inevitable encounter with a catastrophic storm for the next 3 decades - which finally arrived with Katrina in 2005.We've heard this for years, of course. `The Big One' has become a somewhat of a cliche. A plot device for Hollywood movies. But that doesn't make it any less real.
Droughts always end. Even good ones.The Continental United States' 11- year drought in major (CAT 3+) land-falling hurricanes ended just over a year ago when CAT 4 Hurricane Harvey slammed into Texas in August of 2017. Followed, in quick succession by Irma, and Maria.
Our drought in major U.S. earthquakes will end some day as well. And when it does, depending upon where it happens, it could produce the biggest natural disaster in American history.In 2015, the USGS unveiled their UCERF3: A New Earthquake Forecast for California’s Complex Fault System, which raises the risk of seeing a M7.0+ quake in California to 93% between now and 2045. From the summary:
Overall the results confirm previous findings, but with some significant changes because of model improvements. For example, compared to the previous forecast (UCERF2), the likelihood of moderate-sized earthquakes (magnitude 6.5 to 7.5) is lower, whereas that of larger events is higher. This is because of the inclusion of multifault ruptures, where earthquakes are no longer confined to separate, individual faults, but can occasionally rupture multiple faults simultaneously.Three years ago, in USGS: Nearly Half Of U.S. Population Exposed to Potentially Damaging Earthquakes, we looked at the results of a new study – published in the journal Earthquake Spectra, that nearly doubled – to 143 million - the number of Americans who live or work in areas susceptible to potentially damaging seismic ground shaking.
Of particular note, this study didn’t include earthquakes due to human activity – such as `fracking’ - nor did it take into consideration the amplification of ground shaking due to soil type, which could exacerbate the effects of some earthquakes.When you add in that the Gulf and Atlantic coastlines are susceptible to tsunamis generated from distant earthquakes (see East Coast Tsunami Threats), then there is better than a 50-50 chance that you live in an area that is at risk of some seismically induced disaster.
While the `big one' in California (see Dr. Lucy Jones: `Imagine America Without Los Angeles’) is perhaps the most anticipated major disaster of all time, there are other areas in the continental United States equally ripe for a big quake.
- FEMA and the U.S. government recently conducted a huge drill (see FEMA: Cascadia Rising 2016) involving 20,000 people from both the United States and Canada, in order to prepare for a catastrophic M9.0 quake & tsunami off the Pacific coast.
- And in 2011 – during the bicentennial of the four great New Madrid earthquakes of 1811-12 – FEMA and other federal agencies mounted the largest National Level Exercise (NLE) to that date, revolving around a catastrophic earthquake occurring in the New Madrid Seismic Zone (NMSZ) that would involve eight Central U.S. States.
Perhaps least appreciated is the seismic history of South Carolina, which in 1886 was struck by an (Est. 7.3-7.6 magnitude) quake that devastated much of Charleston, South Carolina. Shaking was felt as far north as Boston, south to Cuba, and west as far as New Orleans.An earthquake of that size today, in the same area, it is estimated would produce:
And while you might not live or work in the shake zone of one of the events, should a great quake strike any one of them, the economic and societal impacts could easily spread far beyond the damaged area.
- 45,000 injuries
- 9,000 hospitalizations
- 900 fatalities
- 200,000 displaced or homeless persons
- 20 billion dollars in Damage
Imagine an M8.0 New Madrid quake collapsing major bridges that cross the Mississippi river, buckling the Midwest's railroad tracks and interstate highways, and taking out the dozens of critical natural gas pipelines that snake through that region.A quake of that size could impact the transportation of food, the delivery of energy (power, gas, coal, etc.), the national power grid, and the nation's economy in ways we can only partially imagine.
While we can't prevent the next big quake from happening, we can prepare for it.Working to improve earthquake awareness, preparation, and safety is Shakeout.org, which promotes yearly earthquake drills and education around the country (see A Whole Lotta Shakeouts Going On).
October 18th is International Shakeout Day, when dozens of states and countries practice earthquake safety. If you live in or near one of these seismically active areas, I strongly would urge you, your family, and your employees take part in these yearly drills.
But after the shaking stops, you'll have to find ways to cope with the aftermath. And while the government will send help, you could find yourself pretty much on your own for several days and living in less than comfortable conditions for weeks.For starters - and as a bare minimum - every household should have a disaster plan, a good first aid kit (and the knowledge to use it), an emergency battery operated NWS weather radio, and emergency supplies to last a minimum of 72 hours during a disaster.
While 72 hours is an admirable start, I wouldn't feel comfortable with it. Here in the United States many agencies and organizations recommend that households work towards having a 10-to-14 day supply of food, water, and emergency supplies on hand.
In When 72 Hours Isn’t Enough, I highlighted a colorful, easy-to-follow, 100 page `survival guide’ released by Los Angeles County, that covers everything from earthquake and tsunami preparedness, to getting ready for a pandemic.
While admittedly California-threat specific, this useful guide may be downloaded here (6.5 Mbyte PDF).Despite the abundant seismic risk to the nation (not to mention hurricanes, floods, tornadoes, blizzards, power outages, etc.), according to FEMA: 60% Of Americans Not Practicing For Disasters. Which means there are probably 100 million Americans living in seismically active zones who are not prepared for an earthquake.
My best advice: Don’t be one of them.For more on earthquake preparedness, both here in the United States, and around the world, you may wish to revisit:
California Quakes : Concrete Concerns
Estimating The Economic Impact Of A San Andreas Quake
USGS/OGS Joint Statement On Increased Earthquake Threat To Oklahoma
