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Expensive, but worth it
Years of man-made mistakes must be fixed to save New Orleans
Monday, September 04, 2006
John M. Barry
Hurricane Katrina's devastation of New Orleans was not a natural
disaster. It was a man-made disaster. But it wasn't man-made only
because the levees built by the Army Corps of Engineers proved so
flawed that, as the corps itself said, they offered protection "in name
only." It was man-made in a much larger sense, for even if the levees
had kept New Orleans dry last year, eventually another hurricane would
have ripped the city apart.
That will still happen unless we do something. To understand why that
is, how the city can be protected against Category 5 storms, and why
the national interest requires action, one has to understand the
Mississippi River.
By depositing sediment into what had once been ocean, the river created
about 35,000 square miles of land from Cape Girardeau, Mo., to the
current mouth of the river. As recently as World War II, a land buffer
kept New Orleans reasonably safe from hurricanes.
Three factors changed the geological equation. All three benefited the
rest of the nation but increased New Orleans' vulnerability.
First, the Corps of Engineers prevented the river bank from Minneapolis
south from collapsing into the river by lining hundreds of miles of the
Mississippi River with either riprap or concrete mats. This keeps
shipping moving and provides flood protection but deprives the
Mississippi of millions of tons of soil that historically built land
farther south.
Second, because the river still carries enough sediment to block the
mouth of the river with sandbars, closing it to shipping, the federal
government maintains jetties extending more than 2 miles out into the
Gulf of Mexico. The jetties escort the soil into deep water, allowing
New Orleans to serve as the busiest port in the United States.
But all this deprives the coast -- from Texas to Mississippi -- of the
soil that created it. Coupled with development and levees preventing
replenishment of the land with new sediment, this caused much of the
city to fall below sea level.
Yet these forces have been at work for a century and alone did not put
New Orleans in desperate straits. Virtually all cities near mouths of
deltaic rivers are below sea level. Amsterdam's Schiphol Airport lies
14 feet below sea level, lower than New Orleans. Near Sacramento,
developers want to build on land 20 feet below sea level.
What has enormously increased New Orleans' vulnerability is a more
recent problem: offshore oil and gas wells. These wells account for
more than 30 percent of U.S. domestic energy production. To service
them, the oil industry dug 8,000 miles of pipelines and canals through
the coastal marsh; every inch of those canals and pipelines lets salt
water eat away at the land.
As a result, 2,000 square miles of Louisiana's coast -- some of it
barrier islands, some marsh and some once seemingly as solid as the
land just below Cape Girardeau -- has melted into the sea. The
overwhelming majority of the loss has come in the past 50 years.
All of that land once defended New Orleans against the full force of
hurricanes, soaking up many feet of storm surges. Barrier islands that
no longer exist once helped defend both the Louisiana and Mississippi
Gulf Coast.
So, protecting people hundreds of miles north of New Orleans from river
floods, making Pittsburgh, Minneapolis and Tulsa into ports with ocean
access and supplying oil and gas to America have all made New Orleans
vulnerable.
Yet New Orleans can be protected against great storms. Levees that
survive overtopping would be step one. Step two is building storm surge
barriers, as the Netherlands, Great Britain, Italy and even Providence,
have.
Step three -- the most important and most expensive -- is restoring the
coast. The river still carries enough sediment that, directed to the
right places, it can provide significant protection to the city, even
with the expected rise in sea level. Restoring the coast will cost an
estimated $14.1 billion -- spread over 25 to 30 years. By contrast,
Iraq costs $6 billion a month.
Giving Louisiana the same share of tax revenue from its offshore wells
that New Mexico, Wyoming and other states get from wells drilled on
federal land would cover 100 percent of the cost. Those states justify
getting their share because of the environmental and infrastructure
costs that drilling causes, yet their costs are insignificant compared
with Louisiana's.
More important, protecting New Orleans is the classic example of something we can't afford not to do.
Those who believe New Orleans can survive as a smaller city and still
serve the rest of the country as a port are mistaken. Louisiana
continues to erode: the equivalent of roughly a football field melts
into the sea every hour.
If nothing is done, the city will become a fragile walled island under
constant assault. Nor can the port move to Baton Rouge. The port runs
along almost 70 miles of river, much of which will be threatened.
Energy infrastructure will become even more vulnerable than the city,
and we'll suffer constant supply disruptions and Katrina-like price
spikes.
The Strategic Petroleum Reserve won't help; Katrina knocked out its
pumps and pipelines. Indeed, rebuilding Louisiana's coast might be the
only thing environmentalists and the energy industry agree on.
The most important step in rebuilding New Orleans is assuring residents
and investors that it will be safe. The most important part of that is
committing to build Category 5 hurricane protection. It isn't just New
Orleans that needs it; the national economy needs it.
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