New Madrid Worries Surface in Arkansas

We are preparing for a catastrophic earthquake. The potential, the amount of damage. You have a lot involved with a catastrophic earthquake.
—David Maxwell, director of Arkansas Department of Emergency Management

September 25, 2009
By Jeremy Peppas
The Times; North Little Rock, Ark.

The past is very much the present at the Arkansas Department of Emergency Management.

Image: This map compares the 1906 San Francisco earthquake and the 1811-1812 New Madrid shakers. Even with very similarly sized events such as these, New Madrid region quakes will cause wider damage over larger areas because of the geology's flat layers and lack of complexity. There is little here to stop seismic waves so they can travel much further and cause wider damage. Intensity reports from places shown as blue dots.

Namely what happened nearly 200 years ago, when what became northeast Arkansas, along with other states, were rocked when the New Madrid fault line saw multiple earthquakes that ranged from an estimated 7.2 to 8.1 on the Richter scale, according to the United States Geological Survey.

David Maxwell, the agency director, said last week that his agency, based at Camp Robinson, was making preparations for what he called a “national level exercise” in May 2011 for another major earthquake along the fault line.

Arkansas would be joined by seven other states that make up the Central United States Earthquake Consortium, along with federal agencies.

“We are preparing for a catastrophic earthquake,” Maxwell said. “The potential, the amount of damage. You have a lot involved with a catastrophic earthquake.”

The model that Arkansas is using is for an earthquake of 7.7 or what Maxwell called the “worst-case scenario.”

Sheila Annable is the preparedness division director for the agency and the model estimates that 13,977 Arkansans would be injured to the point of requiring medical attention if the New Madrid were to have another quake, while the same model says 574 would be killed.

Some 127,000 people would be displaced in what makes up the 34-county earthquake zone in Central and Northeast Arkansas.

Those numbers only reflect Arkansas and do not include the nearly one million people who live in Memphis and Shelby County in Tennessee nor any of the others who live in and around the fault line.

“The numbers are too big,” Annable said of the impact to the region. “We just looked at Arkansas.”

Among the concerns expressed by Maxwell and Annable would be disruption to the natural gas lines that supply much of the northeastern United States with fuel for winter heating. Also the national electric grid might be knocked off line that could cause a black out from coast to coast, along with the bridges that cross the Mississippi river that could cause national transportation problems.

Then you have liquefaction.

That’s where shaking associated with earthquakes spreads across the soil and causes the rich farmland of the Delta to become what Annable called “quicksand.”

The soil becomes more sandy and can’t be farmed.

With Arkansas as the No. 1 producer of rice, a New Madrid earthquake could disrupt the global food chain, Annable said.

Another pressing concern of liquefaction is that the land could no longer support the roadbeds making evacuation by vehicle nearly impossible.

While northeast Arkansas has heard earthquake concerns before, namely in 1990 when a major quake was predicted to the day that came and went, Maxwell said the goal wasn’t to “hype this” and “we are just saying it is going to happen one day.”

He added people need to have emergency kits prepared for all manner of events from tornadoes to ice storms and even earthquakes.