NEW ORLEANS IS SINKING
BY JIM WILSON
*** Published on: September 11, 2001
The surge of a Category 5 storm could put New Orleans under 18 ft. of
water. They don't bury the dead in New Orleans. The highest point in the
city is only 6 ft. above sea level, which makes for watery graves.
Fearful that rotting corpses caused epidemics, the city limited ground
burials in 1830. Mausoleums built on soggy cemetery grounds became the
final resting place for generations. Beyond providing a macabre tourist
attraction, these "cities of the dead" serve as a reminder of the Big
Easy's vulnerability to flooding. The reason water rushes into graves is
because New Orleans sits atop a delta made of unconsolidated material
that has washed down the Mississippi River.
Think of the city as a chin jutting out, waiting for a one-two punch
from Mother Nature. The first blow comes from the sky. Hurricanes plying
the Gulf of Mexico push massive domes of water (storm surges) ahead of
their swirling winds. After the surges hit, the second blow strikes from
below. The same swampy delta ground that necessitates above-ground
burials leaves water from the storm surge with no place to go but up.
The fact that New Orleans has not already sunk is a matter of luck. If
slightly different paths had been followed by Hurricanes Camille, which
struck in August 1969, Andrew in August 1992 or George in September
1998, today we might need scuba gear to tour the French Quarter.
"In New Orleans, you never get above sea level, so you're always going
to be isolated during a strong hurricane," says Kay Wilkins of the
southeast Louisiana chapter of the American Red Cross. During a strong
hurricane, the city could be inundated with water blocking all streets
in and out for days, leaving people stranded without electricity and
access to clean drinking water. Many also could die because the city has
few buildings that could withstand the sustained 96- to 100-mph winds
and 6- to 8-ft. storm surges of a Category 2 hurricane. Moving to higher
elevations would be just as dangerous as staying on low ground. Had
Camille, a Category 5 storm, made landfall at New Orleans, instead of
losing her punch before arriving, her winds would have blown twice as
hard and her storm surge would have been three times as high.
Yet knowing all this, area residents have made their potential problem
worse. "Over the past 30 years, the coastal region impacted by Camille
has changed dramatically. Coastal erosion combined with soaring
commercial and residential development in Louisiana, Mississippi and
Alabama have all combined to significantly increase the vulnerability of
the area," says Sandy Ward Eslinger, of the National Oceanographic and
Atmospheric Administration's Coastal Services Center in Charleston, S.C.
Early Warning
Emergency planners believe that it is a foregone conclusion that the Big
Easy someday will be hit by a scouring storm surge. And, given the
tremendous amount of coastal-area development, this watery "big one"
will produce a staggering amount of damage.
Yet, this doesn't necessarily mean that there will be a massive loss of
lives. The key is a new emergency warning system developed by Gregory
Stone, a professor at Louisiana State University (LSU). It is called
WAVCIS, which stands for wave-current surge information system. Within
30 minutes to an hour after raw data is collected from monitoring
stations in the Gulf, an assessment of storm-surge damage would be
available to emergency planners. Disaster relief agencies then would be
able to mobilize resources--rescue personnel, the Red Cross, and so
forth. The $4.5 million WAVCIS project, which is now coming on line,
will fill a major void in the Louisiana storm warning system, which was
practically nonexistent compared to those of other Gulf Coast states.
A system of 20 "weather buoys" along the U.S. coastline serves as a
warning system for the Gulf of Mexico. However, the buoys are not
distributed evenly and Louisiana falls into one of the gaps. From the
mouth of the Mississippi River to the Louisiana-Texas border, there are
no buoys. Only one buoy serves Louisiana, and it is 62 miles east of the
Mississippi River and more than 300 miles to the south. So it's a bit
like predicting the weather in Boston when your thermometer is in
Philadelphia. The other buoys are near the coastlines of Texas,
Mississippi, Alabama and Florida, and several hundred miles out into the
Gulf.
Stable Platforms
One reason that WAVCIS will be more accurate is that its sensors are
attached to offshore oil platforms. The older, floating buoys ride up
and down with the waves and often can't give accurate pictures of wave
heights and storm surges. Stable platforms mean that the sensors can be
placed above and below the water, allowing more precise measurements.
Data from each of the 13 stations, five of which are now on line, is
transmitted to LSU, where it'll be interpreted and sent to emergency
planners centers, via the Internet. "With this new system [WAVCIS], we
get to see real information on storm surge and we can feed that into our
models and come up with real data," says Mike Brown, assistant director
of the New Orleans emergency management office.
Because large areas would have to be evacuated, false alarms could be
harmful to the economy. Stone sees it as a reasonable tradeoff. "It's
better to have that frustration than the loss of life. The potential
loss of life in Louisiana could be catastrophic because there is just
nowhere to go."
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