By State › Arkansas

Arkansas: Risks & Trends

Download all of Arkansas as PDF Print

Same standard as every other page on this site: every figure below is independently sourced, and figures that vary across sources, or measure genuinely different things, are flagged as such rather than collapsed into one number that looks more precise than the underlying data actually supports.

The 2014 Mayflower-Vilonia tornado

MetricFigure
Date April 27, 2014
Rating EF4
Peak winds 190 mph
Path length 41.10 mi
Maximum path width 1,320 yards
Duration 56 minutes
Deaths 16, including one inside an above-ground storm shelter
Injuries 193
Damage $223.45 million (2014 USD)
Communities hit Paron, Mayflower, Lake Conway, Vilonia, El Paso

The above-ground shelter fatality

One of the 16 deaths occurred inside an above-ground storm shelter, believed to be the first documented fatality of its kind in a tornado. It doesn’t mean above-ground shelters are unsafe as a category; it means a shelter’s protection depends on its specific construction, anchoring, and placement relative to the tornado’s actual path and debris field, not on the fact that it is labeled a shelter.

The Guy-Greenbrier earthquake swarm: induced, not natural

MetricFigure
Active period July 2010 - October 2011
Earthquakes detected 14,604 (magnitude -1.5 to 2.9 for the vast majority)
Largest recorded event Magnitude 4.7, night of February 27, 2011
Suspected cause Wastewater disposal wells associated with Fayetteville Shale natural gas drilling, injecting near the Guy-Greenbrier fault
Disposal wells in the area, 2009-2011 6
Regulatory response Arkansas Oil and Gas Commission moratorium on new disposal wells in the area, adopted unanimously July 27, 2011
Outcome after wells shut down Seismicity dropped off within about three months

A hazard that can be turned off

Every other seismic risk on this site, including the New Madrid Seismic Zone covered on Illinois, Missouri, and Tennessee’s pages, is naturally occurring and cannot be switched off by a regulatory order. The Guy-Greenbrier swarm is the exception: once the disposal wells linked to it stopped operating, the earthquakes largely stopped within months. That doesn’t make the risk zero for residents near other active injection sites, but it does mean tracking well permits and Commission actions is a genuinely actionable step in a way that tracking natural fault stress is not.

Sources