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Natural and Unnatural Disasters

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

Brian Hayes

Esprit de Corps

After Hurricane Betsy in 1965, the Army Corps of Engineers drew up a plan to reduce the risk of flooding in New Orleans and other communities on Lake Pontchartrain. The key element of the plan was a system of movable gates to be erected in the narrow passages that connect the lake with the sea. Most of the time, the gates would be left open to allow the free ebb and flow of tides. When a major storm approached, the gates would be closed to seal off the lake from rising Gulf waters. The idea was inspired by the tide gates in the Netherlands designed in the aftermath of a 1953 flood. Another gate guards the Thames basin in Britain.

The Corps' proposal for a storm barrier in Lake Pontchartrain was approved by Congress in 1966, but a dec-ade later construction was just getting under way when a federal court halted the project because of concerns about its effects on the lake environment. By the mid-1980s the storm-barrier proposal had been shelved, and the Corps embarked on a more modest plan for extending and shoring up th network of levees and floodwalls. Even that project has been going slower than expected. A fact sheet issued by the Corps in May of 2005 states, "The major remaining construction is the parallel protection along the London Avenue and Orleans Avenue canals. Completion of this work is scheduled by 2010." (A Corps news release on September 7 said the failures in the 17th Street and London Avenue canals were in places where all scheduled upgrading work had already been completed.)

State and city officials have complained of delays and skimpy budgets for flood-control projects in the past five years. In fiscal year 2005 the Corps requested $22.5 million for the Lake Pontchartrain project, but the budget proposal submitted to Congress by the Bush administration allocated only $3.9 million; Congress increased the amount to $5.5 million. The Corps' fact sheet notes that "Seven contracts are being delayed due to lack [of] funds." For fiscal year 2006 the administration's proposed appropriation fell further to $3.0 million, and the overall budget of the New Orleans District of the Corps was cut by $71.2 million.

Meanwhile, other critics argue that the Corps has done too much rather than too little. Flood-control measures, they say, have hastened the loss of coastal wetlands that might have shielded the city from the  storm. At the southern margin of Louisiana, land  can remain above the waves only with continual replenishment from river-borne sediment. Dams on the upper Mississippi and its tributaries have reduced the river's load of silt, and much of what remains pours directly into the deep waters of the Gulf instead of spreading out over the flood plain. As a result, the land area of southern Louisiana is shrinking by 25 to 35 square miles per year.  The Corps has denied that the loss of wetlands "was a contributing factor in the situation." On the other hand, the Corps also stands ready to solve the problem of wetland loss, through a $14 billion restoration project called Coast 2050. But apart from small pilot studies, the plan has never been funded.

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