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Thin line between mayhem and safety

The Mississippi River rushes through a break in Indian Grave Drainage District levee north of Quincy, Ill., and south of Meyer, Ill., on June 18.

Story: Well before record floods overwhelmed at least two dozen levees in the Mississippi River watershed, government officials at all levels have raised concern about the ability of such structures to protect property and lives. For millions of Americans living in flood-prone places, all that stands between the waters of mayhem and safety is a pile of dirt. Earthen berms, dikes and levees, identical to those overtopped and breached in dozens of places along swollen rivers in the Midwest during the past few weeks, make up the vast majority of flood protection efforts across the United States. A growing list of levees around the country are being found wanting as tougher scrutiny from the U.S. Army Corps of Engineers, state regulators and private engineering firms reveals defects in design and maintenance. Even where levees are well-maintained, as those in the flood zone have been in most instances, officials note that the likelihood of flood levels rising higher than the tops of the berms seems to be increasing, because of a combination of more intense storms and changes in land use. Most of the levees that have been overtopped were built lower because they defend mostly farmland rather than cities. But places like Cedar Rapids, Iowa, and Iowa City saw rivers crest more than 10 feet higher than levels reached in the then record-setting flood of 1993 — making it impossible to pile sand bags high enough or fast enough on their levees to keep the water out. No one at any level of government knows where all the levees are, much less the condition of thousands of the structures. By some estimates, there may be 20,000 to 30,000 levees scattered across the country, but no one is sure. Maintenance of levees, even those operated by the Corps itself, is years and billions of dollars behind schedule. "The levees are already bad and they are going to get worse. This is not a joke. We know this is going to happen."
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