In wake of fast waters, Corps assess fast response

The Cairo, Ill., floodwall stands at 64 feet above sea level.

On a 64-foot-high concrete floodwall in Cairo, Ill., thick black lines denote when the Ohio River got too high:

“1937. 59.5 [feet].”

“1973. 55.7.”

“1975. 56.5.”

Nobody’s marked 2011 yet.

If snow hadn’t broken records, and rain hadn’t broken forecasts, the Missouri, Mississippi and Ohio rivers wouldn’t have swelled like they did this year.  Cairo, Ill., gateway to the South, including New Orleans, wouldn’t have heard its banks slosh invasively.

But the water came, and the U.S. Corps of Engineers had to deal with not its rising height, but rather its two-million cubic-feet-per-second pressure pushing beneath the Birds Point levee.

Volcano-like structures called sand boils erupted fast because of the pressure.  Although the Corps placed sandbags on these mounds to offset the pressure, the boils erupted too fast, indicating the river was getting out of control.  The Corps was playing whack-a-mole against a river.

“You don’t deal with two-million cubic feet of water easily,” Corps Major Jon Korneliussen said. “You let it go where it wants to go.”

The Corps is assessing this fall whether or not opening the levee to relieve the pressure was appropriate.

Five months after the Birds Point levee breach, the Cairo, Ill., floodwall stands deserted. In an empty parking lot in the far background, dozens of punctured sandbags lie in a pile.

— By Sarah Alban, Edited by Joe Pecoraro

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One response to “In wake of fast waters, Corps assess fast response

  1. I better clarify: you want to give the water a place to flow safely, rather than risk it going where you don’t want it.

    Please note the elevation of the floodwall is 64 feet on the Cairo gage, an arbitrary low water reference point on the river. This is referred to as “gage zero”, and is equivalent to an elevation of 270.5 feet above sea level.

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