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Katrina recovery aid: Welfare waste or uncompensated harm?

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Who should pay for recovering from Katrina?

I have found the view of many to be that help from the US federal government should not go too far in subsidising private choices to live below the height of the sea.

My own view is that the federal government is responsible for the enormous damage the New Orleans area has had to absorb. Specifically, the Army Corps of Engineers was grossly negligent in designing levees it claimed would largely protect New Orleans from a storm just like Katrina.[1] As a result of that negligence, several hundred thousand people suffered very substantial harm.[2] (Disclosure: This is my 12th year in New Orleans. While our property is not in the flood plain, it was flooded. Fortunately, being raised, our home was not.)

Unfortunately, the Federal government is unlikely to ever compensate residents of New Orleans for anything but a small fraction of the costs caused by the resultant levee breaches.[3]

For decades, over half a million people[4] have invested their lives and livelihoods in the New Orleans area. They did so in no small part based on the assurance provided by the levee system mandated by Congress and designed, built and overseen by the Army Corps of Engineers.[5]

The levees of New Orleans were breached[6] by waters the Congressional standard, and the Army Corps of Engineers’ own standards, should have contained. In the case of the 17th Street and London Street canals, Katrina generated a storm surge well within their design specifications.[7] However, both these canals suffered catastrophic breaks, flooding the bulk of the “crescent” of the Orleans Parish (the land between its western boundary and the Industrial Canal)[8] and a large swathe of neighboring Metairie (flood map from the Times-Picayune, 9 December 2005). The breaches were not caused by water over-topping the levees, but rather by egregious design flaws.[9] The foundation soils of the levees were not properly accounted for,[10] a conclusion supported by a study from the Army Corps of Engineers.[11]

The Industrial canal failed in three places. Two of these breaches and a large number of other levee breaks along the Intracoastal Waterway, which feeds into the Industrial Canal, and the Mississippi River Gulf Outlet (MR-GO), more on which see below, essentially wiped out East New Orleans, the Lower 9th Ward, and St Bernard Parish. The third breach in the Industrial Canal caused flooding on its west side.

The storm surges along the Industrial Canal and the Intracoastal Waterways were substantially higher than their levees were designed to contain. But this too was a design flaw. It has been well-known that these levees would be over-topped or breached by the storm surge from a level two or fast moving level three storm. This is because these levees were built without properly accounting for the effects of MR-GO. MR-GO is an Army Corps of Engineers’ 1962 white elephant and environmental disaster that also funnels the gulf into the Intracoastal Waterway and Industrial Canal when a hurricane follows a course like that of Katrina.[12]

In short, the flooding of New Orleans was an Army Corps of Engineering disaster. The crescent region of New Orleans was flooded because canals breached under pressure from storm surge well within their design tolerance. These breaches probably represent the most expensive engineering mistake in US history. East New Orleans and the lower 9th ward were flooded because levees were built to withstand a much weaker storm surge than was forecast to occur for the hurricane types these levees were supposed to provide protection against.


[1] “The levees were designed by congressional mandate to fend off floodwater heights — up to about 11 or 13 feet, depending on location — that Category 1 or 2, and some Category 3 storms would kick up.” (John McQuaid, Bob Marshall and Mark Schleifstein, Evidence points to man-made disaster, Human mistakes led to N.O. levee breaches, Times-Picayune, Thursday, December 08, 2005). The levees on the 17th St and London were designed, by the Army Corps of Engineers’ own rules, to hold a surge of 14 feet. Bob Marshall, Overtopping claim won’t hold water, experts say Floodwall standards set in corps manual, Monday, February 06, 2006

[2] Katrina was a relatively small storm when it hit New Orleans with maximum wind gusts of 100 mph (see the bottom of this NOAA summary), or at most a low-end Category Two hurricane on the Simpson-Saffir scale (which requires sustained winds over 96 mph). There was, of course, wind damage in the broad area, but this was relatively minor and would not have prevented the vast bulk of the population from returning within a few days of the hurricane passing.

[3] The extent of damage due to the flooding of Orleans Parish and Metairie is extraordinary. Nearly four months after the initial flooding, about one third of the pre-levee breach population have returned to Orleans, 15 per cent of its schools are open[13], and only one emergency ward (a second, Tulane Hospital, is scheduled to open on February 15th). Brookings also estimates 750,000 households remain displaced over the entire gulf coast.

It would not be hard to demonstrate that the total expenditure of the federal government on Katrina recovery can only amount to a fraction of the costs that the residents of the Orleans, St Bernard, and flooded sections of the Jefferson, Parishes have and continue to bear.

[4] Pre-Katrina the population of Orleans Parish was just under 500,000. Immediately to the west, Metairie, of Jefferson Parish had a population of about 146,000. While Metairie has largely grown over its history, the population of the city of New Orleans reached the half a million mark in the early 1940s and peaked at around 700,000 in the mid-1960s.

[5] The Army Corps of Engineering have essentially had this responsibility since 1937, and was authorized by Congress to build the current levee system in 1965 (for a clear and concise history see The Subcommittee on Water Resources and Environment, Hearing on Expert Views On Hurricane And Flood Protection And Water Resources Planning For A Rebuilt Gulf Coast), but “[t]he levee system’s design dates to the 1950s.” (John McQuaid, Bob Marshall and Mark Schleifstein, Evidence points to man-made disaster, Human mistakes led to N.O. levee breaches, Times-Picayune, Thursday, December 08, 2005). For some sense of the bloody-minded bureaucratic squabbles and politics of levee design and maintenance since the early 1980s see Stephen Braun and Ralph Vartabedian, The politics of flood control: Levees Weakened as New Orleans Board, Federal Engineers Feuded, available in the archives of the Los Angeles Times, December 25, 2005. For a longer history see Bob Marshall, John McQuaid and Mark Schleifstein, For centuries canals kept New Orleans dry. Most people never dreamed they would become Mother Nature’s instrument of destruction, Times-Picayune, Sunday, January 29, 2006

[6] Hurricane Katrina resulted in 58 catastrophic levee failures in the area around New Orleans. One was on the 17th Street Canal, two were on the London Street Canal, and three on the Industrial Canal. The rest occurred largely on levees that lie south and east of the Industrial Canal, notably on the Mississippi River Gulf Outlet (MR-GO) Mark Schleifstein, LSU expert defends piling tests, Corps’ findings no absolution, he says, Times-Picayune, Thursday, December 15, 2005.

[7] “Observational data and computer modeling indicate that storm surge entering the canals from the lake reached heights ranging from 9 to 11 feet in the 17th Street Canal and 11 to 12 feet in the London Avenue Canal. The walls were 13.5 feet high or higher along much of the two canals and were designed to withstand water rising to 11.5 feet.” John McQuaid, Bob Marshall and Mark Schleifstein, Evidence points to man-made disaster, Human mistakes led to N.O. levee breaches, Times-Picayune, Thursday, December 08, 2005. As is standard engineering practice and the Army Corps of Engineers’ own manual (see [1]), all levees or dams built with walls of a given height must be capable of supporting water that fills to that height.

[8] Westward breaches of the Industrial Canal significantly contributed to flooding in the lower southeast segment of the city between Esplanade Street and the Industrial Canal. East New Orleans and the lower 9th Ward lie on the east side of the canal and were flooded by even more disastrous collapses of the east side of the Industrial Canal, and numerous other levee breaches in that region. The breaches in the Industrial Canal were also due to design failures as discussed later in the main body of this piece.

[9] On the 17th Street canal: “”Our geotechnical engineers, when they did their safety calculations, used both sheet pilings to minus 10 and minus 17, and in both cases they indicated that the sheet piles would have failed as the water level in the canal approached 11 feet above sea level, which is exactly what happened in Katrina,” van Heerden [a leader of a state team investigating New Orleans area levee failures] said.” Mark Schleifstein, LSU expert defends piling tests, Corps’ findings no absolution, he says, Times-Picayune, Thursday, December 15, 2005

“The floodwall on the 17th Street Canal levee was destined to fail long before it reached its maximum design load of 14 feet of water because the Army Corps of Engineers underestimated the weak soil layers 10 to 25 feet below the levee, the state’s forensic levee investigation team concluded in a report to be released this week.” Bob Marshall, 17th Street Canal levee was doomed, Report blames corps: Soil could never hold, Times-Picayune, Wednesday, November 30, 2005

“After a 1980 flood caused a stretch of the city’s London Avenue canal levee to collapse, the Army Corps of Engineers proposed replacing it with a fortified design called a T-wall, with sheet pile foundations driven 26 feet deep. And in 1981, a study by Metairie design firm Modjeski & Masters found that proposed higher levees along New Orleans’ 17th Street Canal likely would fail in high water because they were built on ‘very soft clays with minimal cohesion.’

“Yet when levee designs were finalized, the London Avenue Canal wall ended up with a significantly weaker design and the 17th Street walls with shallower foundations. Both canals breached when foundation soil slipped from underneath them as Hurricane Katrina’s storm surge rose on Aug. 29, flooding much of central New Orleans…

“‘There does appear to be a systemic failure along the drainage canals because the failure occurred at two places simultaneously,’ said David Rogers, a geotechnical engineer at the University of Missouri-Rolla who is on a National Science Foundation team studying the breaches. ‘There’s got to be something big that’s causing that. . . . This is a very bad failure mark. It’s telling you they missed the mark by a country mile on the design.'” John McQuaid, Breaches lay bare flaws in design process. Stability concerns date back decades, Times-Picayune, Sunday, December 18, 2005

The same article provides evidence that the Army Corps of Engineers knew of weaknesses in the London St. Canal, and that the implemented levee design was inadequate.

See also [11].

[10] Bob Marshall, Clerical error may have doomed levee. Map maker confuses soil descriptions, Times-Picayune, Saturday, February 04, 2006.

[11] “An internal review by the Army Corps of Engineers supports most of the criticisms leveled against the New Orleans area levee system by an independent team of engineers, including questions about soil strength, levee maintenance and whether the system was built as designed…

“The [Army Corps of Engineers’] task force concurred with the independent engineers from the American Society of Civil Engineers and the National Science Foundation that the failure of levee walls at the 17th Street and London Avenue canals were likely caused by failures in the foundation soils beneath them. The engineers also have noted that sheet piling beneath the walls was too short to properly support the walls.”Mark Schleifstein, Corps’ own study backs critics of levee engineering, Report calls for rebuilding system to do what it was supposed to do, Times-Picayune, Saturday, December 10, 2005

A range of other factors, including inappropriate dredging may have contributed to the levee breaches (Bob Marshall and Sheila Grissett, Dredging led to deep trouble, experts say Levee ‘blowout’ was a concern before project began in 1980s, Times-Picayune, Friday, December 09, 2005). In the case of the 17th Street Canal, the Army Corps of Engineers currently believes that at the breach, the canal was built to its (grossly under-engineered) specifications, that is, the breach was not due due to fraudulent construction practice Mark Schleifstein and Bob Marshall, Corps finds pilings at designed depth. Probe shifts to original plans, Times-Picayune, Wednesday, December 14, 2005. However, there is some evidence of contractor fraud elsewhere Mark Schleifstein, LSU expert defends piling tests. Corps’ findings no absolution, he says, Times-Picayune, Thursday, December 15, 2005.

[12] The problems of MR-GO were known even before it was started in 1962. Hurricane Betsy demonstrated the funneling effect in 1965. ( Matthew Brown, MR-GO goes from hero to villain, Some want channel to stay open, still, Times-Picayune, Sunday, January 08, 2006).

“Three months before Katrina, Hassan Mashriqui, a storm surge expert at Louisiana State University’s Hurricane Center, called MR-GO a ‘critical and fundamental flaw’ in the Corps’ hurricane defenses, a ‘Trojan Horse’ that could amplify storm surges 20 to 40 percent. Following the storm, an engineering investigation and computer modelling showed that the outlet intensified the initial surge by 20 percent, raised the height of the wall of water about three feet, and increased the velocity of the surge from 3 feet per second to 8 feet per second in the funnel. Mashriqui believes this contributed to the scouring that undermined the levees and floodwalls along the outlet and Industrial Canal. ‘Without MRGO, the flooding would have been much less,’ he said. ‘The levees might have overtopped, but they wouldn’t have been washed away.’ ” Mississippi River-Gulf Outlet Canal, Wikipedia. For an alternative source see the New Scientist.

[13] The Brookings Institute provides statistics on post-levee breach developments in New Orleans.

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Written by Admin

February 13, 2006 at 3:19 pm

Posted in Uncategorized

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