A Case Study In Failure

BY MARGARET LOFTUS

When Katrina breached New Orleans’s levees in 2005, engineering schools gained a valuable lesson in design flaws and the tragedy that can result.

By the time it slammed into the Gulf Coast just east of New Orleans on the morning of Aug. 29, 2005, Hurricane Katrina had weakened from a Category 5 storm to a Category 3, but it still had enough power to deal a catastrophic blow to the Big Easy. A 12-foot storm surge breached many of the levees, flooding 80 percent of the city and triggering one of the worst disasters in modern American history. In the end, the storm claimed 1,500 lives and displaced hundreds of thousands of Gulf residents. Total damage has been estimated at some $80 billion.

Hindsight is Instructive

While the breakdown of levees may have been the linchpin of the catastrophe, the groundwork for multiple system failures — from the shrinking wetlands to bungled communication — had been laid long before the hurricane started to churn in the Atlantic. In fact, Katrina was the perfect storm of SNAFUs, making it a rich case study for the classroom. “It’s important that engineering students be exposed to Katrina and other landmark failures,” says Henry Petroski, a professor of civil engineering and history at Duke University and author of Success through Failure: The Paradox of Design. “We learn much more from failures than successes.” Today, Petroski and other engineering educators are using Katrina to teach students not only the technical aspects of flood control but how to consider the social, economic, and institutional impacts of their work.

In his freshman seminar on great projects, Petroski examines how the New Orleans levees failed and what we can learn from that. When engineers design a system, they are supposed to anticipate what can go wrong. But as seasoned engineers know all too well, hindsight is an invaluable teacher. A report released last year by the American Society of Civil Engineers found that the failures of the federally built levees were largely the result of design flaws. “When a large protective system fails, there’s a lot of information that can’t be tested in any other way,” argues Petroski. Maintenance, he adds, is an integral part of design; but in New Orleans, that was found to be inconsistent, at best.

Some levees had sunk as much as two feet in places, says Werner Loehlein, an adjunct civil engineering professor at the University of Pittsburgh who works for the Army Corps of Engineers. He says Katrina shows his students how water systems are at the mercy of several government entities that maintain them. “When you have a long levee that crosses multiple communities that were built at different times, some parts may not be as solid as others.”

Today, the Corps is working to shore up the city’s flood protection system to withstand a 100-year storm level, a project slated for completion by 2011. But the level of protection to which the levees should be built remains controversial, with local and national politicians pushing for a system that could withstand a Category 5 hurricane, a level that could be expected once every 170 years. Robert Houghtalen, the head of the department of civil engineering at Rose-Hulman Institute of Technology uses this case to introduce the concept of a cost-benefit ratio, as even engineering students have a hard time understanding why the levees weren’t designed for the worst-case scenario in the first place. “When you build a project like this, you don’t protect people at the highest level of storm,” Houghtalen explains. “Designs are based on the probability of failure.” Adds Loehlein, “You can’t build for Armageddon.”

The Big Picture

For Alex Mayer, the director of the Center for Water and Society at Michigan Technological University in Houghton, Mich., Katrina is a perfect example of the ways in which water impacts society and vice versa, from the formation of deltas to soil mechanics to climate change. His students are assigned John McPhee’s book, The Control of Nature, for background on how and why the Mississippi River has been manipulated, ultimately carving out a city below sea-level. Mayer also uses Google Earth to underscore New Orleans’s vulnerability to hurricanes and flooding, “When you move the cursor around, it really hits home that New Orleans is a bowl.” The enduring devastation is also apparent: Satellite images taken two years after the hurricane show houses off their foundations and at various angles to each other.

And geotechnological issues are only half of it, says Mayer. To prompt discussion of how institutional and social factors played roles in the disaster, he screens Spike Lee’s four-part HBO documentary When the Levees Broke. “The human side is very clearly shown,” he comments. For example, the film examines the underpinnings of a widely held suspicion among African-Americans in the city that the government purposely blew up flood walls surrounding low-income neighborhoods.

Damage Prevention

Some educators are encouraging their students to come up with their own plans to protect the Gulf Coast residents. In the summer of 2005, Jim Hanson, an assistant professor of civil engineering at Rose-Hulman, was trying to devise a way to teach his structural engineering students the impact of engineering on society when Katrina hit. He asked students to write an essay proposing a solution for reducing the scale of destruction from future hurricanes in New Orleans. Rather than being evaluated on the strength of their proposals — which ranged from raising the elevation of the city to relocating it altogether — students were graded on the number of angles they explored, including crime rates and economic feasibility.

Similarly, some teams in Amber Kemppainen’s engineering modeling and design class at Michigan Technological University are charged with formulating a sustainable solution to protect the city and developing a computer modeling program to show how it works. Plans are evaluated on how well they protect the environment, maintain the economy, and address social issues. Solutions have run the gamut from building flood gates to flooding the city, Venice-style. The advantage of Katrina is that students are already familiar with it, says Kemppainen, “Students aren’t in a bubble; they are socially aware, and keeping class interesting for them means bringing that social awareness into the classroom.”

Service Learning

Denise Wilson, an associate professor of electrical engineering at the University of Washington, takes that concept one step further by leading students to New Orleans itself for full-quarter and mini-quarter programs. Her students rebuild houses by day and review their impressions in a classroom setting in the evenings, discussing issues like the communication breakdowns that contributed to evacuation problems in 2005 and the arsenic and lead contamination that remains in the soil of the Ninth Ward.

Wilson says it wasn’t easy to shoehorn service learning into the rigid engineering curriculum, but she believes the effect it’s had on students has been well worth it. “There’s no substitute for putting engineering students on the scene. When they stay on campus, they start to think solutions should be ideal,” says Wilson. “In New Orleans, they start to chew problems in a way they don’t in the classroom. The impact on society is right there in front of them. The traditional engineering culture just goes away.” She hopes to impart to her students the importance of the technology they are engineering. “The big lesson of this course is that this wasn’t a natural disaster; it was a man-made disaster,” she says. “Katrina was a problem because of the choices we made. It empowers us to make better choices for the future and drives home that as engineers, we have a lot of influence over what goes on in the next century.”

“The big lesson of this course is that this wasn’t a natural disaster; it was a man-made disaster.”

—Denise Wilson, associate professor of electrical engineering at the University of Washington

Margaret Loftus is a freelance writer based in Charleston, S.C.