Corps analysis shows Canal's weaknesses

Katrina made it clear that floodwalls on the 17th Street Canal were in no shape to defend against a major hurricane. Ostensibly built to tolerate storm surge almost 14 feet above sea level, one section of floodwall and levee adjacent to Lakeview failed against water estimated at no more than 10 feet.

Now, a geotechnical analysis of the canal, perhaps the most exhaustive ever performed, indicates that the Lakeview breach was hardly the canal's only weak spot. In fact, almost none of the floodwall sections between Lake Pontchartrain and Pump Station No. 6 can handle the design capacity of 13.9 feet of water, according to the study.

The yearlong study, conducted by the Army Corps of Engineers primarily to determine the canal's "safe water level" for the 2007 hurricane season, divided the 4.8 miles of walls and levee into 36 sections to analyze just how much storm surge each can withstand.

It found that only two sections, those closest to Pump Station No. 6 and on the high ground of Metairie Ridge, can hold more than 13 feet of water. Many other sections of walls and levees can't be counted on to contain more than 7 feet of water.
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