FEMA Warns of Increased Chance of "Big One"

Thursday, April 9, 2015
The areas pictured in red indicate locations where there is at least a two percent chance of a major quake in the next 50 years.(USGS image)

Portions of Southeast Missouri and Northeast Arkansas were rattled by a 3.6 magnitude earthquake last Wednesday, April 1. The quake was centered near Steele, Mo., in the Bootheel, and occurred around 10:51 p.m. Damage was minimal, although the trembler did prompt many discussions among those living along the New Madrid Fault Zone--thought by many experts to be one of the most active earthquake zones in the United States.

Those living in the quake prone area also received some sobering news recently, as the US Geological Survey's National Seismic Hazards Map was updated. The latest information from the USGS indicates the chances of the New Madrid "big one" are much greater than previously thought.

The updates reflect the USGS's best and most recent understanding of when and where earthquakes are likely to occur and how intense they might be. The map was previously released in 2008 and shows earthquake potential across a 50-year period.

But, according to the updated USGS report, "the New Madrid Seismic Zone has been identified to have a larger range of potential earthquake magnitudes than previously identified."

How that would impact residents of Northeast Arkansas is a continuing discussion, and according to Clay County OEM Director Alan Vaughn, it paints a grim picture of life if a monster quake does occur.

"If we have a cataclysmic event in the New Madrid Fault, Clay County will be severely affected," said Vaughn. "Much of Clay County is part of the liquefaction zone and we know the destruction there will be extreme. However, destruction in the area west of the Black River will be significant as well."

Figures compiled by FEMA for a report in 1985 estimated earthquake damage in the millions, and noted the number of deaths would depend greatly on the time of day. "FEMA estimated deaths would be fairly minimal if the quake struck at night," Vaughn explained. "But, if it occurs during the day when school is in session that number would rise dramatically. And, areas closer to the fault will suffer even more damage and deaths."

The estimates for damage to infrastructure within Clay County have been set at 30 to 60 percent, including roads, bridges and railways.

"If this event occurs, lives in Northeast Arkansas and Southeast Missouri as we know it will change probably for a generation. We are talking about massive destruction of infrastructure if we experience a quake of 7.5 to 8 on the Richter scale," Vaughn added.

Officials estimate such a quake could claim between two-tenths and two percent of the population in such areas as Mississippi, New Madrid and Pemiscot counties in Missouri and from one to 10 percent may be seriously injured according to FEMA.

Areas such as Clay and Greene Counties, along with Dunklin, Stoddard and Scott counties in Missouri, could expect to have between two-tenths and two percent of their population killed by such a quake and from one to 10 percent seriously injured.

"There are FEMA plans in place to respond to a very large event. If we have the big event the I-55 corridor is to some extent going to be destroyed so transportation is a big deal," Vaughn added. "SEMA has plans to respond to the region by way of multiple routes to get here and has the capability to build temporary bridges in the event bridges are destroyed or heavily damaged."

While no one can predict the time, date or place of a potential mega-quake, the personnel at Clay County Office of Emergency Management notes such an event is always on the minds of the area's emergency planners.

"At a local level are constantly encouraging the public to prepare for the possible event," Vaughn added. "We need to be prepared. The ability to provide public water, electricity -- those things will be damaged in a way that they can't be recovered in a matter of days."

The new map and other information on seismic events can be found at www.earthquake.usgs.gov and the website www.ready.gov provides an extensive guide on what to do before during and after and earthquake.

According to officials, the New Madrid Seismic Zone, located in southeastern Missouri, northeastern Arkansas, western Tennessee, western Kentucky and southern Illinois, is the nation's most active seismic zone east of the Rocky Mountains.

The zone cuts across the Mississippi River in three places and the Ohio River in two places. More than 200 small earthquakes occur in the region each year. In fact, there have been over a dozen smaller quakes since April 1, including a 1.8 magnitude event early Tuesday morning north of Dyersburg, Tenn.

A log of all quakes occurring in the past six months may be found on the website of the University of Memphis Center for Earthquake Research and Information at www.memphis.edu/ceri Those wanting additional information on local preparedness may call the Clay County OEM office at 870 598-5365 or visit them in the Piggott courthouse.

The month of February has been set aside as Earthquake Awareness Month, coinciding with the anniversary of the 1812 earthquake of Feb. 7, of that year. The 7.7 magnitude quake which occurred at that time is considered to be the largest recorded in post-settlement time in the United States.

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