- COCODRIE, La. - In this southern Louisiana hamlet you can tell the age
of someone's house by how high up in the air it is.
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- New trailer homes hang 16 feet off the
ground on wooden pilings, their wheels whistling in the breeze coming
off the Gulf of Mexico. Older homes sit on 10- or 12-foot pilings, while
the oldest - the ones that survived 1992's Hurricane Andrew - stand on
short stilts just a few feet off the ground. Ground that's only 3 feet
above sea level, and "sinking" fast.
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- The marshes that make up virtually all
of southern Louisiana are vanishing at a staggering rate of 25 to 35 square
miles a year. Since 1930, the state has lost more than a million acres
- an area larger than the state of Rhode Island - as marsh and swamp turn
into open ocean and lakes.
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- If the loss continues, Cocodrie and 18
other town sites will be underwater by 2050, along with most of the southern
part of the state. The city of New Orleans will sit on an island abutting
the hurricane-prone waters of the Gulf of Mexico, a nightmare for evacuation
planners.
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- Those estimates don't take into account
sea-level rise predictions due to global warming. Scientists estimate
the world's seas will rise by 1 to 3 feet over the next century due to
global warming. Southern Louisiana is the part of the United States that
is most vulnerable to sea-level rise: a low-lying region already experiencing
rapid land-loss due to human engineering and industrial projects.
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- "We're the poster child for climate
change in the U.S.," says Len Bahr, executive assistant to Gov. Mike
Foster Jr. "Southern Louisiana is sinking at an incredible rate.
Any raising of global sea levels is going to jeopardize our efforts to
save and protect the coast."
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- Southern Louisiana's dramatic land loss
is due to a combination of manmade changes to marshes, swamps, and water
circulation patterns across Louisiana and the 31 other states that share
the Mississippi River watershed.
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- Much of Southern Louisiana is a vast,
low alluvial plain created by the Mississippi River. This land was deposited
here bit by bit in the form of river sediments carried from as far away
as the Rockies and the upper Midwest. The Mississippi continually created
more land at its mouth in a lobe-shape delta.
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- Every thousand years or so the river
would change course, finding a more direct path to the Gulf of Mexico
and would begin creating a new lobe-shape delta at its new mouth. The old
river channel would become a sluggish bayou and some of the new lands
would sink or erode away until the river changed course again. The coast
would constantly change shape, but taken as a whole it was continually
growing.
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- Until recently, that is.
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- Over the past 150 years, people have
attempted to control the Mississippi in an effort to prevent flooding,
improve navigation and protect settlements, farms, and industry along the
river and throughout the delta. Ever-larger levees have been constructed
to keep the Mississippi confined to its main channel. Many branches and
bayous were cut off from the main river by the enormous earthen levees,
which now stand several stories high on both sides of the river.
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- "The delta has been sealed off from
the river that created and sustained it," says Mark Davis, director
of the Coalition to Restore Coastal Louisiana, a Baton Rouge-based nongovernment
organization. "The landscape has to be re-engineered to reunite the
river and its floodplain."
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- Cut off from the river and spring floods,
marsh plants no longer received the sediments, freshwater, and other conditions
necessary to remain healthy. For the past century, they have been dying
at a rapid rate, and the marshes have turned into lakes or sunk into the
Gulf of Mexico.
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- In recent decades, scientists say the
problem has been made much worse by the oil and gas industry, which cut
vast networks of canals through the marshes to gain access to fossil-fuel
deposits found throughout the delta. Marshes adjacent to the canals then
collapsed because of seawater intrusion or died after being sealed off
by the raised, artificial banks of the crisscrossing canals.
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- "If we're to reverse land loss,
people need to look at wetlands as ecological systems," says Louisiana
State University coastal scientist Gene Turner, who thinks canals - not
Mississippi levees - are the biggest cause of wetland loss. "If water
levels can't rise and fall naturally, these plants die and the land sinks
away."
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- As wetlands vanish at a rate of more
than 40 acres a day, the homes and livelihoods of tens of thousands of
bayou residents are put into jeopardy. The enormous Gulf shrimp industry
is threatened because shrimp - and most other commercially important fish
stocks - rely on the marshes for critical phases of their life cycles.
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- Although surrounded by enormous levees,
the city of New Orleans is becoming increasingly vulnerable to hurricanes
as it loses the wetlands that shield it from Gulf storms. The city is
home to 1.2 million people, but almost half of its metropolitan core is
below sea level. Evacuation is difficult because only a handful of highways
span the levees and planners rely on the Superdome and downtown office
buildings to serve as "vertical evacuation" sites in the event
of a severe hurricane.
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- "Given the loss of wetlands and
the recent tendency toward more intense storms, there are serious questions
about whether (hurricane defenses) provide the level of protection that
people think they do," says Randy Hanchey, former director of engineering
for the Mississippi Valley Division of the Army Corps of Engineers in
Vicksburg, Miss.
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- There are also questions about how to
respond to the land-loss crisis.
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- State and federal authorities are in
the midst of an ongoing effort to fund and construct new levee structures
that would divert some of the Mississippi's flow into adjacent basins
and marshes. They hope this will slow or reverse land loss by rejuvenating
marshes with sediments and freshwater.
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- Under the 1990 Coastal Wetlands Protection
and Wetlands Act - sponsored by Louisiana Sens. John Breaux and J. Bennett
Johnston - some $240 million in federal and state funds have been invested
in 81 projects to protect the coast, including diversions, shoreline
stabilization, and sand-dune construction. But complicated inter-agency
relationships and a shortage of state matching funds have hampered progress.
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- These projects - together with two much
larger federal diversion projects costing another $130 million - will only
prevent an estimated 22 percent of the expected land loss over the next
50 years.
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- "It's not that nothing's being done,
it's just that it's an order of magnitude less than what is needed,"
Bahr says. "We need to think on a much larger scale."
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- A joint federal-state task-force study
proposes a vast array of projects to re-engineer the movement of water
and sediment across the entire southern half of the state. Gates, locks,
pumps, dams, diversion structures, and artificial reefs would be constructed;
shorelines, river banks, and entire Gulf shore islands would be stabilized
- all with the intention of restoring more natural drainage patterns to
the region.
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- The price tag is an estimated $14 billion,
much of which would have to come from federal coffers. Getting that kind
of money would be tricky for any state. Louisiana is further handicapped
by its "colorful" politics - a euphemism for its legacy of corruption
and graft.
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- Nor does it help that the state continues
to issue new permits for canal dredging to the oil and gas industries
- one of the largest causes of land loss in the state.
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- Oliver Houck, director of the environmental
law program at Tulane University in New Orleans, says a great deal could
be accomplished relatively cheaply, if state lawmakers required companies
to backfill canals and other marsh facilities at the end of their productive
life - a difficult task since the oil and gas industries have considerable
political influence in the state.
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- "Louisiana argues that the country
must help pay for wetland restoration, but refuses to take measures to
protect marshes from further losses," Houck says. To have credibility
when seeking billions in federal funds, skeptics argue, the state needs
to show leadership in wetlands protection.
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- "We may have to wait for a major
disaster before people will really want to do anything about this problem,"
says Davis, whose organization has played a leading role in rallying support
for the issue. "We want to put everything we can in place so that
when that day comes, we can tell people exactly what needs to be done."
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