As various plans emerge for the recovery of New Orleans, these panelists offer some pointed lessons in flood prevention and reconstruction, from overseas, from our own history, and from other parts of the U.S.

Anne Whiston Spirn believes in the power of catastrophe to transform cities beneficially. In particular, she embraces “ideals of designing a city in concert with natural processes.” But it takes collective will to discard old planning schemes. In West Philadelphia, Spirn discovered that whole neighborhoods were sinking due to their construction on landfill over an old creek. Kids called where they lived “the bottom”—and they didn’t mean just on the floodplain, but socio-economically, explains Spirn. She documented her findings and offered city planners ways to turn these sinkholes into viable and attractive community assets. Officials ignored her, until affected residents got involved. While New Orleans is “dramatic and riveting, it’s but the tip of the iceberg,” as hundreds of communities across the U.S. face the same story of dangerous and unhealthy living conditions and official neglect.

As colossal as the Katrina flooding was, a 1927 Mississippi flood proved far more destructive. Michael M.J. Fischer describes how wet weather lodged over the nation’s midsection for half a year, leading to the flooding of 23 thousand square miles, from Virginia to Oklahoma, and displacement of more than 1 million people. Officials dynamited dykes that protected rural areas along the Mississippi, “forcing the rural poor to sacrifice for the city -- and used troops to suppress the threat of civil war,” recounts Fischer. Sharecroppers were “pressed at gunpoint” into repairing the levees, protecting the interests of large cotton and sugar firms. Fischer sees “echoes in the Bush administration lifting of rules on paying prevailing wages.” He notes that these coercive measures permanently changed race relations in that region, and led to an exodus of many African Americans from the Delta.

Even without Katrina, New Orleans has been inexorably sinking—due to coastal erosion, oil and gas drilling and global warming. But these problems afflict other global landmarks just as dramatically, says Chiang Mei. Look at poor Venice, which has been debating for 20 years now the construction of gates on its famous lagoons. The community, engineers, business and government simply can’t collaborate on an acceptable solution, says Mei, and this “jewel of the western world” hangs in the balance. The Netherlands is more than 50% below sea level, so “protection against flood has been a matter of survival” for centuries. A massive 1953 flood launched the nation’s most ambitious effort: a shift from dams to moveable gates. In an astonishingly swift timeframe, the Dutch engineered a means to protect their land from “10,000-year storms,” and to maintain their valuable estuary ecosystems, home to mussels and oysters. Will New Orleans reconstruction adopt “Band-Aids vs. long-term solutions,” wonders Mei, and how much of a role will environmental impact play?