An Unnatural Metropolis: Wresting New Orleans from Nature (review)

Before Hurricane Katrina devastated New Orleans in the summer of 2005, most of us knew a lot less about the Crescent City than we do today. This timely book, which appeared just eight months before storm waves overwhelmed the city's levees, is one of the key works that have enabled us to learn so much so fast. Craig Colten tracks the environmental challenges that the residents of New Orleans have wrestled with for close to three centuries as they have tried to control the water threatening them from the north, south, occasionally the west, and even from the sky above and the ground below. Colten recognizes that such a story is not only about nature but people as well, and he does much to further the ongoing integration of environmental and social history. A geographer with a keen eye for issues of race and class, Colten demonstrates that the natural environment has been one of the most important factors shaping the social and physical development of New Orleans.

The alluvial floodplain that became New Orleans was a terrible site for a city. Colten explains that the Mississippi regularly overflowed its banks there, and the elevated water table encouraged a wetland environment that rested on highly compressible subsoils. As a result, river floods and standing water have perennially plagued the city. Residents responded from an early date by building levees to hold back the river and digging canals to drain water into Lake Pontchartrain. In the twentieth century, they began using pumps to dry out wetlands and remove the approximately sixty inches of rain that fell every year. But despite these efforts to control the area's challenging environment, the best that the builders of New Orleans could produce was a city inside a shallow earthen bowl that is difficult to bale out and slowly sinking into the ground.

The city's unique site complicated a host of environmental problems that often hit poor whites and African Americans hardest. In the nineteenth century, New Orleans endured many of the same afflictions suffered by contemporary cities: tainted water, poorly drained sewage, standing garbage, and offensive industries ranging from slaughterhouses to tanneries. But some of these problems posed greater challenges for New Orleans than other urban sites. The extremely low elevation made it impossible to drain the city without expensive pumps, and the only practical source of drinking water—the Mississippi—also served as a sink for up-river industries. To make matters worse, surging water from the river and lake frequently flooded the city, and standing water provided a breeding ground for mosquitoes that spread the deadly yellow fever virus. New Orleans' poor whites and blacks often lived in the lowest areas and bore a disproportionate amount of the suffering. Colten explains that, unlike in the arid American West where water has always flowed toward money, in New Orleans it has always flowed toward poverty.

Colten also reveals the long history of failure that has dogged the levees intended to protect New Orleans. Early levees were never entirely up to the job, and twentieth-century urban sprawl magnified the problem considerably. Beginning in the nineteen twenties, the city and its suburbs opened vast new areas to development by draining wetlands between the city and lake and ringing them with levees. Homes soon covered the former marshes and swamps, but storm-driven waves bested the new levees over and over again throughout the century. Development continued nonetheless, and a familiar pattern in New Orleans repeated itself in the city's suburbs, where minority populations still endure worse flooding than their white neighbors.

One of Colten's most important contributions is his effort to counter the long-standing scholarly assumption that cities are nature's antithesis. He insists instead that cities are always embedded in natural environments and rely on them for their very survival. This point cannot be overemphasized: Cities are not divorced from nature, even though they sometimes seem as...