"New Orleans is a disaster waiting to happen. The city lies below sea
level, in a bowl bordered by levees that fend off Lake Pontchartrain to
the north and the Mississippi River to the south and west. And because
of a damning confluence of factors, the city is sinking further,
putting it at increasing flood risk after even minor storms. The
low-lying Mississippi Delta, which buffers the city from the gulf, is
also rapidly disappearing. A year from now another 25 to 30 square
miles of delta marsh-an area the size of Manhattan-will have
vanished. An acre disappears every 24 minutes. Each loss gives a storm
surge a clearer path to wash over the delta and pour into the bowl,
trapping one million people inside and another million in surrounding
communities. Extensive evacuation would be impossible because the
surging water would cut off the few escape routes. Scientists at
Louisiana State University (L.S.U.), who have modeled hundreds of
possible storm tracks on advanced computers, predict that more than
100,000 people could die. The body bags wouldn't go very far."
-"Drowning New Orleans," Scientific American, October 2001

"New Orleans is sinking. And its main buffer from a hurricane, the
protective Mississippi River delta, is quickly eroding away, leaving
the historic city perilously close to disaster. So vulnerable, in fact,
that earlier this year the Federal Emergency Management Agency ranked
the potential damage to New Orleans as among the three likeliest, most
castastrophic disasters facing this country. The other two? A massive
earthquake in San Francisco, and, almost prophetically, a terrorist
attack on New York City. The New Orleans hurricane scenario may be the
deadliest of all. In the face of an approaching storm, scientists say,
the city's less-than-adequate evacuation routes would strand 250,000
people or more, and probably kill one of 10 left behind as the city
drowned under 20 feet of water. Thousands of refugees could land in
Houston. Economically, the toll would be shattering. Southern Louisiana
produces one-third of the country's seafood, one-fifth of its oil and
one-quarter of its natural gas. The city's tourism, lifeblood of the
French Quarter, would cease to exist. The Big Easy might never recover
.. . ."
-Eric Berger, "Keeping Its Head Above Water: New Orleans Faces
Doomsday Scenario," Houston Chronicle, December 1, 2001

"The Federal Emergency Management Agency lists a hurricane strike on
New Orleans as one of the most dire threats to the nation, up there
with a large earthquake in California or a terrorist attack on New York
City. Even the Red Cross no longer opens hurricane shelters in the
city, claiming the risk to its workers is too great.

'The killer for Louisiana is a Category Three storm at 72 hours before
landfall that becomes a Category Four at 48 hours and a Category Five
at 24 hours-coming from the worst direction,' says Joe Suhayda, a
retired coastal engineer at Louisiana State University who has spent 30
years studying the coast. Suhayda is sitting in a lakefront restaurant
on an actual August afternoon sipping lemonade and talking about the
chinks in the city's hurricane armor. 'I don't think people realize how
precarious we are,' Suhayda says, watching sailboats glide by. 'Our
technology is great when it works. But when it fails, it's going to
make things much worse.'

The chances of such a storm hitting New Orleans in any given year are
slight, but the danger is growing. Climatologists predict that powerful
storms may occur more frequently this century, while rising sea level
from global warming is putting low-lying coasts at greater risk. 'It's
not if it will happen,' says University of New Orleans geologist Shea
Penland. 'It's when.'

Yet just as the risks of a killer storm are rising, the city's natural
defenses are quietly melting away. From the Mississippi border to the
Texas state line, Louisiana is losing its protective fringe of marshes
and barrier islands faster than any place in the U.S. Since the 1930s
some 1,900 square miles (4,900 square kilometers) of coastal
wetlands-a swath nearly the size of Delaware or almost twice that of
Luxembourg-have vanished beneath the Gulf of Mexico. Despite nearly
half a billion dollars spent over the past decade to stem the tide, the
state continues to lose about 25 square miles (65 square kilometers) of
land each year, roughly one acre every 33 minutes.

A cocktail of natural and human factors is putting the coast under.
Delta soils naturally compact and sink over time, eventually giving way
to open water unless fresh layers of sediment offset the subsidence.
The Mississippi's spring floods once maintained that balance, but the
annual deluges were often disastrous. After a devastating flood in
1927, levees were raised along the river and lined with concrete,
effectively funneling the marsh-building sediments to the deep waters
of the Gulf. Since the 1950s engineers have also cut more than 8,000
miles (13,000 kilometers) of canals through the marsh for petroleum
exploration and ship traffic. These new ditches sliced the wetlands
into a giant jigsaw puzzle, increasing erosion and allowing lethal
doses of salt water to infiltrate brackish and freshwater marshes."
-"Gone With the Water," National Geographic, October 2004

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