NOVA Home Find out what's coming up on air Listing of previous NOVA Web sites NOVA's history Subscribe to the NOVA bulletin Lesson plans and more for teachers NOVA RSS feeds Tell us what you think Program transcripts Buy NOVA videos or DVDs Watch NOVA programs online Answers to frequently asked questions

The Man Who Knew

Storm That Drowned a City homepage

"A slow-moving Category 3 hurricane or larger will flood the city. There will be between 17 and 20 feet of standing water, and New Orleans as we now know it will no longer exist."
Ivor van Heerden, October 29, 2004

For years, Ivor van Heerden, a hurricane expert at Louisiana State University, has seen it coming. Since 2001, he and colleagues have been generating computer models of how a major storm could inundate the region in and around New Orleans. And he and his team sought tenaciously—at times desperately—to have their warnings heeded by government officials.

In an interview with NOVA ten months before Katrina, van Heerden expressed some of his worst fears as well as his understanding that the federal government, and the Federal Emergency Management Agency in particular, were finally grasping the need to prepare for a calamity. But in interviews conducted in Katrina's wake, van Heerden's anger at the federal government's response is clear.

Following are excerpts from van Heerden's interviews, both pre- (this page) and post-Katrina (next page).

Before the Flood

Interview conducted October 29, 2004

NOVA: If this region—New Orleans, the wetlands, and all—were a patient in the hospital, how would you describe them? At what stage are they?

VAN HEERDEN: Close to death.

NOVA: Really? Don't hold back.

VAN HEERDEN: (laughter) Thank you. Louisiana is a terminally ill patient requiring major surgery, a patient that if it was given a new heart and new lungs and a new liver would live. If it isn't, it's going to die. That's the equivalent.

An ominous scenario

NOVA: Walk me through the worst-case scenario—if a hurricane hits New Orleans.

VAN HEERDEN: If we look at the case of a slow-moving Category 3 passing west of the city, the floodwaters push into Lake Pontchartrain, and then they push through some highly industrialized areas. As they pass through these areas, they pick up a lot of chemicals. Remember, the flooding is occurring at the same time as a lot of wind damage, a lot of things breaking and coming apart. So these highly contaminated waters then flow into the city.

Within the city you have about 300,000 people who haven't left. There are about 57,000 families in New Orleans that don't own a motor vehicle. They can't get out. There are numerous homeless folk who can't get out. And then there's the disabled or bedridden. And those are the folk who have the least resources, the least ability to cope with what's going to happen.

While the flooding starts, these people are dealing with the winds pulling buildings apart, trees coming down, whatever. For the first five hours the water rises very slowly. But then it rises very, very rapidly. It rises higher than the average home's roof. So those 300,000 people, most of them, are going to have to leave their homes. They're going to end up hanging on to light poles, trees, trying to swim to high-rise buildings.

“We’re in essence going to have a refugee camp.”

There is the potential for extremely high casualties—people not only killed by flying debris, drowning in the soup, but also just imagine, how do we rescue the survivors? Unlike a river flood, it doesn't come up and go down. The water stays. And it stays for months and months and months. How do you rescue all of these people? If there's 200,000 survivors, you get 20,000 out a day, that's 10 days. So how are they going to hang on? You know, this is one of the big nightmares: how do you rescue those survivors? What are they going to need?

They're going to need to be detoxified. And this is Louisiana—it's 100 degrees Fahrenheit, 100 percent humidity. Putrefaction and fermentation go on very, very rapidly. So those folk are going to be surrounded by the proverbial witches' brew of toxins.

In addition to the folk that have to be rescued, we've got about 700,000 residents who can't come home. They're going to have to be housed in tent cities. When you start pulling groups of people like this into close confinement, the potential of very serious diseases goes up dramatically.

So just imagine, you've got this super, super crowding—highly, highly stressed folk. They don't have a home. They don't have a job. They don't see any future. They're living in tents. It's hot, humid Louisiana. And now you have the potential of disease.

These are some of the worst-case scenarios. We will have almost a million displaced persons that are going to be totally dependent on the state. We're in essence going to have a refugee camp. And it's going to require a massive operation to try and bring some normality into these people's lives.

Preparing for disaster

NOVA: Is this something that a state can handle? The State of Louisiana?

VAN HEERDEN: No, this is definitely something that requires the full resources of the U.S. government. We are fortunate that the federal government is starting to recognize that this is a serious problem. In July of this year [2004] we had an exercise called the Hurricane Pam exercise, where all the federal agencies got together with state agencies. We did a simulation of what would happen, and then these agencies got together and tried to decide how they would deal with a flooded New Orleans. So there is some recognition now, especially by the Federal Emergency Management Agency, that this is a catastrophe that's right on the horizon.

NOVA: How great is the risk of this happening?

VAN HEERDEN: If we look in the last eight years, we have had two near misses of New Orleans [Hurricane Georges in 1998 and Hurricane Ivan in 2004]. And as the wetlands fall apart, the potential of these hurricanes to do major destruction through storm surges rises and rises and rises. So every year that goes by, the probability of this killer storm occurring increases. Statistics right now would suggest maybe once every seven to eight years we're going to have a near miss.

NOVA: So if there's a chance of a big hurricane and this scenario playing out every seven or eight years, what's the solution? What could be done?

VAN HEERDEN: There are two very important mitigation activities that the federal government has to pursue today. Number one is our wetlands protect us from a surge. Our wetlands and barrier islands are our outer line of defense. We need to restore them. Now, that's in the longer term.

In the shorter term, we can start thinking about how can we reduce the amount of water that flows into Lake Pontchartrain and then floods the city? We need to be really innovative, think outside the box, and in addition we've got to change the way federal government does business. You can't give these sort of projects to the Corps of Engineers and have them mull over it for 20 years before it gets built. We need a group that's independent of the political system, that's well funded, has the right experts advising it, and then gets in and does it.

“Every year that goes by, the probability of this killer storm occurring increases.”

This is the United States of America. This is the most powerful country in the world. It has unbelievable resources. At, literally, the snap of the President's finger, we can spend $40 billion in Iraq. If we can start rebuilding their infrastructure immediately, we can do the same thing back home. At the snap of the President's finger, perhaps, we could spend the $16-20 billion that's needed to save New Orleans. All it takes is the will to do it.

NOVA: What do you think it takes to create that will? Does it take a catastrophe?

VAN HEERDEN: The unfortunate thing is, it does look like it's going to need a catastrophe in order to mobilize it.

Continue to the post-Katrina interview.

Back to top

van Heerden

Ivor van Heerden was haunted by the knowledge that a major hurricane would devastate New Orleans. He is deputy director of the Louisiana State University Hurricane Center, and since 2001, he has led a team studying the public health impacts of hurricanes on the city.

Enlarge this image


At the Hurricane Pam exercise in June of 2004, van Heerden showed FEMA officials and others a computer model of how a slow-moving Category 3 storm passing west of New Orleans would flood the city. In some areas, storm surge would cause more than 20 feet of standing water. Play the simulation.

Enlarge this image


New Orleans' Superdome served as a makeshift refugee camp. While van Heerden's nightmare scenario didn't play out in full, his vision of destitute survivors was all too prescient.

Enlarge this image

Storm That Drowned a City
The Man Who Knew

The Man Who Knew
Hurricane expert Ivor van Heerden saw Katrina coming for years.

A 300-Year Struggle

A 300-Year Struggle
Follow the Big Easy's ever-bigger battles with water.

Flood Proofing Cities

Flood Proofing Cities
What can New Orleans learn from other flood-prone places?

Anatomy of Katrina

Anatomy of Katrina
Track her from her birth off Africa to her clash with the Gulf Coast.

How New Orleans Flooded

How New Orleans Flooded
Annotated before-and-after satellite imagery shows where and how.

Map the Flood

Map the Flood
See how much of your area would have been submerged.

Send Feedback Image Credits
NOVA Home Find out what's coming up on air Listing of previous NOVA Web sites NOVA's history Subscribe to the NOVA bulletin Lesson plans and more for teachers NOVA RSS feeds Tell us what you think Program transcripts Buy NOVA videos or DVDs Watch NOVA programs online Answers to frequently asked questions