Flash floods kill at least nineteen campers in Arkansas

Monday, June 14, 2010

Map of Ouachita River river system. The rescue effort centres around the Little Missouri (highlighted) and Caddo rivers.

Search and rescue workers in Arkansas continue to search the Little Missouri and Caddo Rivers for survivors of Friday's flash flood. At least nineteen people were killed when the flood swept through the Albert Pike Recreation Area campground in the Ouachita National Forest in the southwestern portion of the state.

Initially, Arkansas governor Mike Beebe said twenty people were killed when the flash flood reached its peak at about 5:30 a.m. local time on Friday morning, but as of Monday the death toll stands at nineteen. Amongst the dead are at least six children under seven who died when what has been described as a "wall of water" swept away campers while they slept.

With no record of who and how many people were at the camp site, rescue workers initially thought up to 40 people were missing, estimating numbers from vehicles and camping equipment remaining. Temporary cell phone towers have been erected in the area, in the hope that survivors would be able to call for help.

Speaking to CNN on Saturday, Bill Sadler, an Arkansas State Police spokesman, said: "We believe there are still individuals trapped in the area." He added that "The primary mission of the Arkansas state police working with the local authorities right now is to get the living out of that area and locate the dead." Most of those who had thought to be missing have now been accounted for.

Survivors describe having to cling to trees to avoid being swept away. Others escaped by climbing into higher ground. Rescuers hope that those missing can still be found alive on these higher grounds. The flood swept away everything from automobiles to RVs and, though it pales in comparison to floods like to much bigger flash floods like the Big Thompson Canyon flood in Colorado of 1976 that killed 144, many people at the site of the disaster said they "had never heard of anything like this."

This was such a huge, huge fast-moving event.

—John Nichols, U.S Forest Service geologist

Surrounded by mountains, the camp site "filled up like a bowl", according to Chad Stover, a spokesman for the Arkansas Department of Emergency Management. The area where the flooding happened is known as a "flash flood alley". This is due to the hilly topography, which creates a bowl like effect that drains rainfall into smaller streams. That means if there's a lot of rainfall, it will all go into the streams that can flood very easily.

The remains of the camp ground following the floods.
Image: NOAA.

Before the actual torrent of water came, the waters of the Little Missouri river increased at a very rapid rate. At 2:00 a.m Friday, the waters of the Little Missouri river were just 3.8 feet, according to US Geological Survey river gauge logs. However, it surged to 10 feet over the next hour and peaked at 23.4 feet, which is almost 20 feet above the river's norm. It also exceeded the river's previous record by 10 feet. After the peak, the river dropped back to 8 feet by noon.

Raymond Slade, a Texas-based U.S Geological Survey hydrologist and an expert on floods, said that the amount of rainfall could have exceeded seven inches in an hour, a phenomenon so rare that scientists call that a "100-year rainfall". Slade says that "This was much greater than a 100-year rainfall. That flood that occurred was much bigger than a 100-year flood, where those people were camped."


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