Why did the levees fail in New Orleans?
Engineer Robert Bea talks about his investigation.
The National Science Foundation awarded Robert Bea, along with a team of other scientists, a grant to investigate why the levees of New Orleans failed. Bea is a professor at the University of California, Berkeley, in the Department of Civil and Environmental Engineering. He’s co–director of the Marine Technology and Management Group at the Center for Risk Mitigation. Bea has over 48 years of experience in engineering and management of design, construction, maintenance, operation, and decommissioning marine systems including offshore platforms, pipelines, and floating facilities.
Dr. Bea spoke with Earth & Sky’s Jorge Salazar in December 2005.
Salazar: Dr. Bea, since the catastrophic flooding caused in the aftermath of Hurricane Katrina, what is the progress in rebuilding the system of protective levees in New Orleans?
Bea: Thanks to the Army Corps of Engineers, some remarkable progress has been made. First, in de–watering the city. That was what had to be done immediately following Katrina. And then they’ve been able to stabilize most of the breach sites, so that water intrusion is now very minimal. And, they are affecting repairs to the breached site so that they can essentially bring the system back to the pre–Katrina conditions. They’re even adding additional protection to keep the components from potentially failing when loaded again. So, they’ve made some really great progress.
Salazar: Would you relate for us, please, your involvement in investigating the levee failure, and what’s being done to address the upcoming hurricane season in June?
Bea: As to my background, it goes back to 1954, a long time ago. At that time I was a young engineer in training for the U.S. Army Corps of Engineers. I was working in southern Florida, on the South Florida Flood Control and Activities, building levees, and helping dig canals and install pump stations. And then I left the Corps in 1959. And you can fast forward to 1965. At that time I was located in New Orleans, serving as Shell Oil Company’s chief offshore civil engineer. And I got to experience Hurricane Betsy.
We lost our home, we lost all of our belongings due to levee overtopping and levee breaching. Those two sets of experiences have given me some interesting insights that were then resumed when I first got notice about Hurricane Katrina approaching the Gulf coast. That was on August 24. And then on August 29, I got a notice from one of my friends in New Orleans that the levees had breached. It was late September by the time that I arrived on–sight as a member of a team of engineers sponsored by the National Science Foundation. And, since that time, I’ve been back in the area repeatedly, doing surveys from the land, from the air, from the water, in an attempt, for one, to find out why the system didn’t perform as we wanted it to.
A good reason for doing that is to learn how those kinds of things happen so that as you begin to move forward, you don’t repeat the old mistakes. We’re about at the stage now where I think that we have a reasonably coherent understanding of how the failures happen, and a reasonably coherent understanding of the progress that’s been made to restabilize the system. We’ve also made reached reasonable understanding about the alternatives that need to be explored in order to provide secure, long–term protection for the people of New Orleans.
With a personal background of having survived a flood and lost everything in it, including our home, my sensitivity is particularly sharpened for the issue concerning adequate protection for people. At the present stage, we’ve essentially gotten through what I call the “battle field triage stage.” We’ve stabilized the wounded victim. We’re now trying to understand how to transport that victim to a place that’s secure so that we can do long–term repairs. And that’s essentially trying to get ready for the forthcoming hurricane system.
We know the current system has been injured and damaged, just like someone injured and damaged on the battlefield. And we’re doing the best that we can to stabilize that victim. At the same time we know that, at all costs, we have to avoid doing harm during the process of rescue and stabilization. Thanks again to the efforts of the U.S. Army Corps of Engineers and the contractors and people who are really working hard to make the system okay, we’re getting back to a reasonable condition for June 1 (NOTE: June 1 is the official beginning of hurricane season).
Now one of the things that concerns me is that in this rush to get things back by June 1. The first thing one has to recognize is that June 2 works too. The big, intense hurricanes generally come in August and September. So, it tells me to look out for slogans and goals that don’t really mean a lot to the long–term things and short term things that need to be done, but can exert unreasonable pressures to meet those unreasonable goals.
We’ve seen some signs of that pressure to satisfy goals. One can say, “Well, Bob, that’s criticism.” And I think that it’s not so much criticism as a plea for sensibility, as we understand the risks and rewards of the things that we’re attempting to do, and also to understand the responsibilities of the things that we’re doing.
When we tell people that it’s okay to come back and start rebuilding your homes and your lives, there is a responsibility for what I call “the consequences of unintended things.” I’m talking about breaches and flooding and those kinds of things. My caution is to proceed very carefully so that we don’t build up unrealizable expectations on the part of the people who are struggling to rebuild their lives in that community.
Salazar: One the one hand, government engineers have been reported saying that the levees will be ready by the start of this year’s Hurricane season, and on the other hand, Paul Kemp, of the Hurricane Center at L.S.U. related to me that at present, the levees rebuilt are little more than mounds of dirt, with little chance of actual hurricane protection. Where does reality fit in between these two descriptions?
Bea: Jorge, that’s a beautiful question to ask, and a difficult question to answer. Mixed up in it is what I was attempting to say before: look out for the slogans. You know, “finish by June first.” “Reestablish the system to the pre–Katrina condition.” Those slogans can drive people to do things that we would not do ordinarily.
This is an attempt to meet the goals, meet the standards, but we have to make sure that the goals and the standards are the right ones. So, the objective is not to “reestablish the system to the pre–Katrina condition.” I think we’ve already got empirical experience that the level of protection provided pre–Katrina was not acceptable. The city, with this level and kinds of protection, has suffered two very, very significant flooding events. So, we know that in that 40–year period from Betsy to the current time, that we failed to get into place adequate protection. And so to say that we’ll reestablish it back to that level, should tell people that we are still exposed to a degree, or level that’s not acceptable to the general public or to the United States.
The next step says, “Okay, well we’re rushing. We’re trying to fill those holes, we’re doing the best we can to stabilize the system.” And I say,“Okay, we are in fact doing the best that we collectively can.” But as as soon as we get the patient to the operating room, that’s the point where we’ve reached the first of June, then the first thing that we should do is sit down and start thinking, start thinking about the long–term securing of this very unique and wonderful part of the world, so that we don’t fall back into the trap that we did in 1965.
In 1965, we resolved that we would never have an event like Hurricane Betsy again. And yet, almost 40 years to the day, I go back to the site of my previous home in New Orleans and see a new home there, and the owners are dragging wet mattresses out of the front door. It tells me that with all of that struggle, and with all of that resolution, in 40 years we’ve failed to get it done. And, to think that we can “get it done” by the first of June in 2006, I think is potentially seriously misleading people into this false sense of confidence regarding the level of protection that they’ve actually got.
My personal opinion is that the level of protection is not adequate, even as established to the pre–Katrina condition, to confront the kinds of severe storms that can turn this area back into a soup bowl filled with water and people’s lives. So, okay, we’re back to the first of June, my long–term focus is to say, “Let’s now think about how to put an adequate level of protection into place so that this will not happen again.
The Corps has some right into what they’re saying. Paul Kemp and the Louisiana State University team certainly have some right in their views. We have some right in the view that have developed from the National Science Foundation team, and recently the American Society of Civil Engineers team that’s working with the U.S. Army Corps of Engineers investigation group, which has come out with very, very strong statements regarding the inadequacy of the system that we have, inadequacy of the organizational structure that we have. Those findings duplicate things that we found and have documented since last year.
So, I think that we’re starting to get a coherent view about what needs to go forward and be done to provide an adequate level of protection. The question is, will we do it?
Salazar: What does the recovery process look like for the “patient,” the system of protections that include levees surrounding New Orleans?
Bea: Very good question, I think that recovery for this “patient” says that, well we kind of know that the level of protection that an area like this needs would require substantial improvements to the flood defense facilities.
And, indeed, we have another part in this world that has struggled with such an issue, and that’s the Netherlands. Thanks to a year’s assignment for Oil Dutch Shell, I was able to spend a lot of time learning about that system, and have continued to follow it as an engineer whose specialty is risk assessment and management. We know that there is a system that has been put in place, and came from a country’s resolve that they wouldn’t experience another flood like they did in 1953. And they’ve gone forward, and made some marvelous progress.
Yes, they have made some mistakes. And they’ve been learning and profiting from those mistakes. They have continually improved their system. That’s a way of saying that we can understand how to adequately defend this part of the world, but it’s going to take a different approach from what we did in the Netherlands. And this approach, I think, has started to get clear thanks to the efforts from a lot of different of different communities, many of which are outside of engineering. They say, “Okay, there’s a natural defense system that nature has provided for this part of the world.” And the first thing that we need to do is understand that system.
In our field trips and our surveys soon after Hurricanes Katrina and Rita, we certainly saw the effect of wetlands and barrier beaches and adequately protecting areas. We saw the benefits of building homes even outside of the protective systems, building them high into the air, on stilts. That’s been done in other parts of the world. So there’s a natural defense system, and we need to supplement that system with an unnatural one constructed by people.
And there’s where levees, and pump stations, and flood gates, and these sorts of things start to come into focus. At this point, you have a cooperation going on between conventional engineering technology and the natural technology of how an area like a delta conventionally refurbishes and defends itself.
So, we’re learning that this can be done, but it’s not going to be done quickly. It is going to cost a significant amount of money. That says that we have to have a resolve that will not waver. You can’t turn this on and off, like we did as we moved from Hurricane Betsy to Hurricane Katrina. The next thing you have to do is adequately provision that resolve. That means the right organization, the right people, the right kinds of technology that are developing this cooperation to provide a reasonable, long–term protection for this part of the world. And it can be done without breaking our bank.
Salazar: The American Society of Civil Engineers released a report this week criticizing the rebuilt levees for lacking the “armoring” needed to withstand flood water. What do you see as necessary medicine for the “patient” in the short term?
Bea: Excellent question. The first thing that I would say is that the American Society of Civil Engineers report is a heroic statement of some of the very critical things that need to be thought about in the short term.
We’ve similarly issued letters and reports that are cautioning. As we look at the short term stabilization of the area, we need to proceed very carefully and proceed very responsibly. And the Corps is saying that out on the levees that are adjacent, when we pile up that soil, we need to defend that soil. We know, certainly, that most of the soil, we wouldn’t use it unless we had to. So we say, “Okay, we have to. Let’s make sure we defend it.”
And at that point, I know that the Corps of Engineers knows that. We’ve had discussions with their people, and they say, “Okay, Bob, we can only do what we’re authorized to do.” That also means funded. So if they have adequate funding and adequate authorization, those good people, those good engineers, will get into place things that we can be proud of. However, if the authorization is not forthcoming, if the materials, equipment and people cannot be provided because we haven’t authorized it, then we have what I call dangerous concealment.
Here we have assured people that it’s okay to come back and start again. Certainly we have piled the soil back up to where it was, but unwittingly have dangerously concealed a hazard. And that’s not fair to people. And I think that the American Society of Civil Engineers is trying to say, “Let’s be careful. Let’s not leave things out exposed and not properly protect them.” And that includes people.
Salazar: Thank you for taking time out today, Dr. Bea. Is there anything else that you’d like to share with the public or the listeners of Earth & Sky?
Bea: Well, I think that the thing that I would like to share with the pubic and the wonderful program Earth & Sky is the fundamental problem that we face in providing long term protection for this part of the world is fundamentally not an engineering or technology problem.
After 53 years of practice, I’m convinced that we know how to do this. The real challenge is mobilizing the will of the United States to help provide adequate protection for this part of the world. At that point, we will put into place the necessary organizational, political people and resources to accomplish that goal. Once that will is mobilized, it can be done. The challenge is, will it?
