It's been more than five years since Hurricane Katrina punished New Orleans and the coast of Mississippi; still, to geologist Stephen A. Nelson there remains a passion, an anger, about what happened, how it could have been prevented, about opportunities lost.
To him, the storm wasn't merely a metaphor for the incomprehensibility of nature or the incompetence of government; it was personal.
It was home.
"I’ve lived in New Orleans since 1979,” says Nelson, associate professor/chair, department of earth and environmental sciences at Tulane University, “and as long as I have lived here there has always been a push to get a hurricane protection system that would protect us from a Category 5 hurricane."
The system is still not in place.
Perhaps to exorcize those demons – certainly to help explain them – Nelson will be leading a pre-meeting field trip at this year's AAPG annual convention called “Hurricane Katrina – What Happened? The Geology of the Katrina Disaster in New Orleans.”
And what happened, he'll tell you, was a perfect storm of not only nature's fury but of human short-sightedness.
"In New Orleans," he said, "the severe damage and deaths were caused because the hurricane protection levees and flood walls … were breached to flood the city."
And while admitting there were other factors and results, it was that breach that caused the most and significant damage.
"Yes, there was wind damage, but recovery from that would have been relatively quick,” he said. “The fact that 80 percent of the city was flooded as a result of the levee breaches and that the water could not be pumped back out for several weeks was what caused the most severe damage. The levees that failed were all levees built on human made navigation and drainage canals that provided a direct path for storm surge to get into the heart of the city."
These canals, he said, should never have been built.
"It is not a good idea to construct canals that give direct access of storm surge into the heart of a populated place like New Orleans,” he said. “But, since this has already been done, we need to build a first line of defense that keeps the water out of those canals rather than relying on a levee and flood wall system on the banks of the canals."
His field trip at this year's convention will allow participants to get a first-hand look at many decades of bad ideas.
It won't be pretty.
The tour will encompass and help to explain all the geological, engineering and historical factors responsible for the devastation – including the most heart-wrenching, those that occurred to the city's most vulnerable and impoverished area, its 9th Ward.
And while the finger-pointing continues even today, Nelson knows where to point first.
"What made this area vulnerable was the construction of the Inner Harbor Navigation Canal, Intracoastal Waterway and Mississippi Gulf Outlet, all of which funnel storm surge into the heart of the city."
Nelson explained that the first hurricane protection system was conceived after Hurricane Betsy in 1965. Authorized by Congress in the Flood Control Act of 1965, the $85 million project was expected to take 13 years to complete and protect New Orleans from a fast moving Category 3 storm.
This type of storm, Nelson commented, was expected to strike once every 200 to 300 years. The project, which was still unfinished a year before Katrina, had ballooned in price to $738 million and a completion date of 2015.
Nelson said the initial funding was never enough, it was never constant and, since 30 percent of the cost was to be collected locally, he thinks there was always pressure from local residents to reduce their share.
Additionally, there were lawsuits from environmentalists; fighting between the New Orleans Sewerage and Water Board, the agency responsible for removing rain water from the city, and the Corps of Engineers; and general incompetence.
"In my opinion, this likely led to decisions that were not in the best interest of safety … all of which resulted in sacrifices that ultimately led to a substandard hurricane protection system."
To Nelson, the problem was not one of just degree but of kind, for the system had to do a number of things:
"We realized that such a system must also involve measures to slow coastal erosion and restore coastal areas that had been eroded over the last 50 years."
It's impossible to put in dollar figures, fully, the cost of Hurricane Katrina, but Nelson says most believed a project to have bolstered those levees would have been about $35 billion – or about a fifth of what will eventually be spent on clean-up, rebuilding and relocation.
"If such a project had been carried out in a timely fashion," Nelson says, "then yes, in my opinion much of the devastation could have been prevented."
It's not just a prediction.
In September 2008, for instance, as Hurricane Gustav was approaching New Orleans, an evacuation order was issued. This time, according to Nelson, a substantial effort was made to provide a means of evacuation for those without the ability or economic means to leave.
"Although Gustav did not result in a disaster for New Orleans, lives certainly would have been saved had Gustav made a direct hit,” he said. “My biggest concern, however, is that the lessons learned will be forgotten over the next several years as memories fade and press coverage wanes.”
In thinking of the future storms and the welcome mat that is those channels and canals, Nelson is even more concerned.
"My hope is that complacency will not once again result in another catastrophe."
He’s not the first to warn of such things.
Four hundred years ago, in “The Tempest,” Shakespeare wrote of another storm, also one of enormous consequent and frenzied confusion:
Stephen Nelson, chair of the department of earth and environmental sciences at Tulane University, will lead the field trip “Hurricane Katrina – What Happened? The Geology of the Katrina Disaster in New Orleans,” on Saturday, April 10, the day before the AAPG Annual Convention and Exhibition opens.
This field trip will travel to the sites of the major levee breaches to explore the geological, historical and engineering factors responsible for the breaches and resulting flooding.
A preliminary field trip guide and other material can be found at http://www.tulane.edu/~sanelson/Katrina/index.html.