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In ENR online - an article suggesting that the original designs and/or the original construction of levees in New Orleans were perhaps incorrect....
ENR Article
ENR Article
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New Orleans "malfeasance"? 1
- Thread starter JAE
- Start date
electricpete
Electrical
That's just a tease. Mention of allegations but you can't see the details unless you pay $4.95?
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A lead engineer-investigator studying why New Orleans levees and floodwalls failed during Hurricane Katrina says his team has heard suggestions that there was "malfeasance" in the flood protection system's design or construction, including allegations that some elements were not built to specifications.
New Orleans interior canal levees and flood walls failed with explosive force in some locations.
(Photo by Tom Sawyer)
Raymond B Seed, a professor of civil and environmental engineering at the University of California at Berkeley, told a Senate Homeland Security and Governmental Affairs Committee hearing on Nov. 2 that sheet piles may not have been driven to the depths called for in design drawings.
A preliminary report released at the hearing on causes of the flood-protection failures produced by several teams of engineering investigators said that while overtopping of levees was the prime reason for most of the failures, some of the critical canal breaches seem to have resulted from foundation soil and levee embankment failures. The teams included groups from the American Society of Civil Engineers, Louisiana State University's Hurricane Research Center and a National Science Foundation-supported team led by Cal-Berkeley.
Ivor van Heerden, deputy director of the LSU hurricane center, testified that preliminary findings show that breaches of the 17th Street, London Avenue and Industrial Canal levees constituted "a geotechnical engineering failure." He said the 17th Street and London Avenue breaches were "due to a design that did not account for the very weak nature of the soils."
"Most of the flooding was due to man's follies," van Heerden added.
Peter Nicholson, an associate professor of civil and environmental engineering at the University of Hawaii, said investigators "found literally dozens of breaches throughout the many miles of levee system" and added that "many of the levee problems involved significant soil-related issues." Nicholson, testifying for ASCE, said the team found "no evidence of overtopping" at the 17th Street Canal breach and north breach at the London Avenue Canal.
Committee Chairman Susan Collins (R-Maine) said the witnesses' testimony "demonstrates that many of the widespread failures throughout the levee system were not solely the result of Mother Nature."
Senior Corps of Engineers officers and policy makers were not among the witnesses appearing before the committee. Paul Mlakar, a senior resource scientist at the Army's Engineer Research and Development Center, did testify, and cautioned against arriving at conclusions about the levee failures "before appropriate analysis is accomplished." He said an interagency task force will be doing such a study, which is scheduled to be completed July 1.
Related Link:
# Go to to see testimony and data from the hearing.
The Corps has been doing levee repairs and has said it is aiming to restore the New Orleans levees to their pre-Katrina protection level--to withstand a Category 3 hurricane-- by June 1, the start of the 2006 hurricane season. Mlakar said the interagency task force would provide relevant information from its review to the Corps earlier than July to aid its rebuilding plan.
Nicholson also said ASCE recommends that Congress establish a national levee inspection program similar to the current National Dam Safety Program.
In addition, LSU's van Heerden advocated wetlands restoration and creation of barrier islands as a outer line of storm protection. Coastal Louisiana has lost substantial amounts of wetlands over the past decades. If the area's wetlands were as extensive as they were 100 years ago, van Heerden said, "The surge [from Katrina] would have been dramatically less."
After the hearing, Seed told reporters that his team had heard reports from "engineers, contractors, and in some cases widows thereof" regarding possible design or construction problems including using "sheet pile lengths that were less than were perhaps called for" Seed said that at part of the 17th Street Canal, his team has "design information which would show the piles being 14, 16, 17 or 27 feet [long] and now we have stories that suggest they may have been 20" [feet.]
Seed also said another report dealt with wet fill materials being brought in instead of the specified dry, compactable materials. "We're talking about a dozen sources or so right now and many of them are giving us information specific to a site, in some cases a few sites." He declined to be more specific about the reports or the sources.
New Orleans interior canal levees and flood walls failed with explosive force in some locations.
(Photo by Tom Sawyer)
Raymond B Seed, a professor of civil and environmental engineering at the University of California at Berkeley, told a Senate Homeland Security and Governmental Affairs Committee hearing on Nov. 2 that sheet piles may not have been driven to the depths called for in design drawings.
A preliminary report released at the hearing on causes of the flood-protection failures produced by several teams of engineering investigators said that while overtopping of levees was the prime reason for most of the failures, some of the critical canal breaches seem to have resulted from foundation soil and levee embankment failures. The teams included groups from the American Society of Civil Engineers, Louisiana State University's Hurricane Research Center and a National Science Foundation-supported team led by Cal-Berkeley.
Ivor van Heerden, deputy director of the LSU hurricane center, testified that preliminary findings show that breaches of the 17th Street, London Avenue and Industrial Canal levees constituted "a geotechnical engineering failure." He said the 17th Street and London Avenue breaches were "due to a design that did not account for the very weak nature of the soils."
"Most of the flooding was due to man's follies," van Heerden added.
Peter Nicholson, an associate professor of civil and environmental engineering at the University of Hawaii, said investigators "found literally dozens of breaches throughout the many miles of levee system" and added that "many of the levee problems involved significant soil-related issues." Nicholson, testifying for ASCE, said the team found "no evidence of overtopping" at the 17th Street Canal breach and north breach at the London Avenue Canal.
Committee Chairman Susan Collins (R-Maine) said the witnesses' testimony "demonstrates that many of the widespread failures throughout the levee system were not solely the result of Mother Nature."
Senior Corps of Engineers officers and policy makers were not among the witnesses appearing before the committee. Paul Mlakar, a senior resource scientist at the Army's Engineer Research and Development Center, did testify, and cautioned against arriving at conclusions about the levee failures "before appropriate analysis is accomplished." He said an interagency task force will be doing such a study, which is scheduled to be completed July 1.
Related Link:
# Go to to see testimony and data from the hearing.
The Corps has been doing levee repairs and has said it is aiming to restore the New Orleans levees to their pre-Katrina protection level--to withstand a Category 3 hurricane-- by June 1, the start of the 2006 hurricane season. Mlakar said the interagency task force would provide relevant information from its review to the Corps earlier than July to aid its rebuilding plan.
Nicholson also said ASCE recommends that Congress establish a national levee inspection program similar to the current National Dam Safety Program.
In addition, LSU's van Heerden advocated wetlands restoration and creation of barrier islands as a outer line of storm protection. Coastal Louisiana has lost substantial amounts of wetlands over the past decades. If the area's wetlands were as extensive as they were 100 years ago, van Heerden said, "The surge [from Katrina] would have been dramatically less."
After the hearing, Seed told reporters that his team had heard reports from "engineers, contractors, and in some cases widows thereof" regarding possible design or construction problems including using "sheet pile lengths that were less than were perhaps called for" Seed said that at part of the 17th Street Canal, his team has "design information which would show the piles being 14, 16, 17 or 27 feet [long] and now we have stories that suggest they may have been 20" [feet.]
Seed also said another report dealt with wet fill materials being brought in instead of the specified dry, compactable materials. "We're talking about a dozen sources or so right now and many of them are giving us information specific to a site, in some cases a few sites." He declined to be more specific about the reports or the sources.
All of this just reinforces the point that we should have (should have had) a levee safety program similar to the existing dam safety program in the US. Especially in situations like New Orleans where the levees closely resemble dams in the way the operate. If they had been classified as dams instead of levees, the design would have been for the probable maximum flood which no doubt would have been the Cat 5 storm with full storm surge. Emergency spillways, zoned embankments, posative cutoffs and good QA/QC during construction, as well as appropriate hydrology and freeboard requirements if incorporated into the design of the levees, would have resulted in much safer structures. The Corps does this as a matter of course in their dam designs and should have done it for their levees also.
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