Katrina, the Corps of Engineers and Politics

The history of the drainage ("outfall") canal system in New Orleans goes back more than a century. The 17th street outfall canal dates to before WWI (at least 1913). The political control was the purvey of the Orleans Levee Board (OLB) who had authority over the land primarily, the Sewer and Water Board who had control over the use of the canal for drainage, and the Corps of Engineers who were charged to protect the city from storm surges. In the 1960's enter the Lake Pontchartrain's wetlands environmental groups who wanted to preserve wildlife, fishing, swimming and boating interests. The Corps was always under the the fiscal control of Congress, but this is mainly a problem of sales and consensus building for the Corps that they are used to and expert at. After hurricane Betsy, in the 1960's the Corps developed a "barrier plan" similar to the Dutch Zuider Zee. It would have controlled the storm surge in Lake Pontchartrain by means of a lock and dam installed in the Rigolettes ). This proposal was delayed and stymied by environmental and economic concerns and was abandoned in the late 1980's for the "high level plan" which involved raising the height of the levees and flood wall along the outfall canals. This decision put NOLA at great risk and transferred the responsibility of the canals to the OLD and SWB. Then the SWB in attempting to improve its ability to drain rainfall from the City requested permission from the Corps to dredge the 17th street canal to improve it drainage efficiency. In spite of warnings, the Corps granted the permit and dredging was completed in the late 1990's. Warnings were ignored that pointed to the exact spot where the levee later failed. All of this can be read in the Legal Brief on the class action suit against the Corps and the U.S.
The Judge dismissed the complaints because citizens can't sue the government but his words are damning to say the least:

This story–fifty years in the making–is heart-wrenching. Millions of dollars were squandered in building a levee system with respect to these outfall canals which was known to be inadequate by the Corps’ own calculations. The byzantine funding and appropriation
methods for this undertaking were in large part a cause of this failure. In addition, the failure of Congress to oversee the building of the LPV and the failure to recognize that it was flawed from practically the outset–using the wrong calculations for storm surge, failing to take into account subsidence, failing to take into account issues of the strength of canal walls at the 17th Street Canal while allowing the scouring out of the canal–rest with those who are charged with oversight. The cruel irony here is that the Corps cast a blind eye, either as a result of executive directives or bureaucratic parsimony, to flooding caused by drainage needs and until therwise directed by Congress, solely focused on flooding caused by storm surge. Nonetheless, damage caused by either type of flooding is ultimately borne by the same public . Such egregious myopia is a caricature of bureaucratic inefficiency. It is not within this Court’s power to address the wrongs committed. It is hopefully within the citizens of the United States’ power to address the failures of our laws and agencies. If not, it is certain that another tragedy such as this will occur again.

STANWOOD R. DUVAL, JR.
UNITED STATES DISTRICT COURT JUDGE

Katrina the Corps and Science

The story of the flooding of New Orleans is now full of Urban Myths mostly perpetrated by the Corps of Engineers. It was NOT A NATURAL DISASTER. It was an ENGINEERING FAILURE comparable to CHERNOBYL. The design of the levees was fatally flawed and the Corps is busily trying to hide that fact from the public. They have hired a public relations firm and lobbied to have a Geologist critic fired from LSU and have accused him of spreading miss information because he is not an engineer. The partial story is at NY Times If you want the full story, go to: http://levees.org/index. The short story is that Katrina, although a large and dangerous storm, was down graded to category three before landfall. The storm surge, although high, was not a record breaker and was LOWER THAN THE DESIGNED MAXIMUM storm surge height. The flaw in their design was a simple one in my theory. Civil Engineers are used to designing buildings and structures that sit vertically and are subject to gravitational forces. The Levees most of their life time just sit there and do the same. The exception came when the storm surge raised the level of water to a considerable height. The shape of the stress ellipsoid was changed suddenly as a significant horizontal force perpendicular to the Levee was introduced by the hydrostatic component from the filled canal. The design engineers had used the compressional strength of the soils and now suddenly the SHEAR STRENGTH of the soils became a critical factor. The result was classic slumping of the levee, i.e., the horizontal thrusting of the levee until it completely breached. The post mortem on the levee showed that the cement T-wall was not over topped and back eroded as the Corps now contends. Rather, the entire levee was thrust more than 45 feet to the side and then the wall fell over(See the Independent Engineering Report fig 2.3b) . This was a predictable response to the forces involved if one took the time to model the levee as it was subjected to the forces of the surge and if one used the appropriate physical constants. We in the Earth Sciences have encountered Engineers
who have a limited concept of stress and strain relationships in the presence of anisotropy (almost certainly a factor in the soils), abnormal fluid pressure (certainly a factor), and significant stresses that are not vertical. The storm surge raised the water level (hydrostatic head) by about 10 feet . This increased (abnormal) fluid pressure was transmitted via the porous canal bottoms into the soils that supported the levee. The increased pressure caused a decrease in the soil strength (both compressional and shearing). As a result, a predictable failure of the levee occurred. A structural Geologist would look at this from the standpoint of M. King Hubbert's classic paper, "THE ROLE OF FLUID PRESSURE IN MECHANICS OF OVER THRUST FAULTING ", and would draw similarities to the Thrust Faults of the Canadian and Montana Rockies. The Corps explanation was that the levees were over topped and eroded from behind and that this was a 500 year event. So now we are faced with a Corps that has ignored Geologic and Geophysical advice for decades and has hired a PR firm with Tax Payer money to fight the bad press. We are also faced with a professional society, the American Society of Civil Engineers (ACSE) that has taken $2MM from the Corps to study the failures and has come up with a rosy picture of the Corps and tried to make Katrina out to be a storm of all storms which will never happen again (see link conflict of interest) . A Geologist activist at LSU has been fired for speaking out and the Corps has continued to shed the blame(Geologist(s) Slandered). Some Corps members have resorted to childish name calling (reference). I call on the members of the Geo Science community to take heed and even join the fight if you will. Katrina was only one example of the Corps failures. Many years ago when I was a Grad Student, I took a Graduate level course in Ground Water Hydrology. Most of the course was a diatribe against the Corps and all of its screw-ups. The USGS has been ignored while the Corps has gotten the go ahead to screw-up again and again. Join the Fight!
This is an ongoing problem. The Corps has obviously had some revised modeling done and it must have caused some panic because they started a new testing program on the repaired flood walls (Reference). This is a point of critical importance to the City and its future because if the repaired flood wall cannot stand up to several feet of water, then the rainfall in the City cannot effectively and promptly be pumped out to the lake. This will mean that the City will flood every time it rains hard. We have already had newly rebuilt and refurbished homes in Lake View flooded by rain because the Corps hadn't gotten the pumps working right - but that's a different Corps screw-up with the pumps that didn't work. How long do the Citizens of NOLA have to endure this incompetence and the attempts to cover it up?