For approximately 300 years, residents of the New Orleans area have been struggling to keep their heads above water. The city’s landscape, on average, falls six feet below sea level. Levees, man-made constructions of clay, silt or sand, are built to protect residents from the surrounding bodies of water — Lake Pontchartrain, the Gulf of Mexico and the Mississippi River.
In 1726, these levees ranged from four to six feet tall. By 1858, there were more than 1,000 miles of levees, up to 38 feet high, surrounding New Orleans. In 1926, the Army Corps of Engineers declared that future floods were preventable. Yet flood waters continue to cause damage. Hurricane Katrina is one of five debilitating hurricanes in the past 60 years to challenge human resilience in the city nicknamed “The Big Easy.”
“Based on what I’ve seen on television news, I think that my home is missing a roof,” said Susan Jackson, a spokesperson for the Army Corps of Engineers in New Orleans.
Constructed to endure Category 3 hurricanes, the levees, with steel-enforced concrete floodwalls on top of them, were outmatched when Hurricane Katrina hit Louisiana with Category 4 winds of 140 mph. Jackson stated that each parish has a levee board. Federal, state and local funds support levee construction and maintenance.
“We were given enough money for Category 3 prevention,” Jackson said.
According to the Army Corps of Engineers, the levees didn’t fail. Instead, an overtopping of water landed with enough mass force on the dry side of the levees to cause a loosening of earthen support which then undermined the floodwalls. The results were a 300-foot breach on London Street’s floodwall, a 450-foot breach on 17th street and a 500-foot breach on Industrial Canal. In the case of 17th street, the dislocated portion of the floodwall moved laterally about 20 feet before it fell and disappeared under the water.
In a press release, the Corps of Engineers stated that levees in New Orleans are inspected annually and that district officials have won awards for their expertise.
The amount of time required to drain the water out of New Orleans is unknown. The Corps is ordering five 42-inch pumps, which will pump 100 cubic feet per second. Corps employees are repairing the breaches in the levees and floodwalls before pumping begins.
“It’s miraculous that things have held up so well,” Jackson said.