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Natural and Unnatural Disasters

Reflections on a city made possible and made vulnerable by reliance on technology

Brian Hayes

A few years ago I made a pilgrimage to Pumping Station No. 6, which sits athwart the 17th Street canal in New Orleans. Approaching from the intake side, I found a brick building whose entire facade was hidden behind an immense "trash rack," a grille of steel bars that intercept floating debris. Inside, bulbous steel casings enclosed pumps 12 feet in diameter, driven by equally large electric motors. Much of this machinery was installed in 1915 and has a certain antique splendor about it, but the pumps are not museum pieces; they are still among the most powerful in the world. It is these pumps, along with a network of drainage canals and a ring of protective levees, that made it possible to build a sprawling city in the cypress swamps between the Mississippi River and Lake Pontchartrain, where half a million people have been living "below ground zero," as one fleeing resident recently described the place.

Pumping Station No. 6...Click to Enlarge Image

The pumps are just a small part of the engineered infrastructure that underpins the existence of New Orleans and its suburbs. The entire lower reach of the Mississippi River runs through an artificially stabilized channel. The banks are armored with stone and concrete and surmounted with levees and floodwalls. In some places the course of the river has been straightened; almost everywhere the channel has been dredged. A few miles upriver from New Orleans, the Bonnet Carré Spillway drains flood waters into Lake Pontchartrain. Farther upstream, even bigger spillways at Morganza and Old River divert seasonal overflows into the Atchafalaya River, which empties into the Gulf of Mexico at Morgan City, 50 miles west of New Orleans.

All of this hydraulic engineering has been remarkably successful, at least in the narrow sense that floods on the lower Mississippi have been contained and controlled. New Orleans has not had river water in its streets for more than a century. But the river is not the only threat to the city—and this was already well known even before Hurricane Katrina made it painfully clear at the end of August.



 

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