Trouble in the Gulf Part 2: A Vanishing Paradise

This is Part Two in a three-part series on the loss of
Louisiana’s coastal wetlands and the effect of this loss on
waterfowl and other species that migrate to or through the region
from the Upper Midwest. Until the recent Deepwater Horizon oil
disaster, most of us who live in the North have taken the Louisiana
coast for granted, if we have thought of it at all. We may be
vaguely aware of the fact that most of the waterfowl produced in
the northern states of the Mississippi Flyway winter here, but we
probably don’t know that it is disappearing at an alarming
rate.

The first thing a visitor from the Great Lakes region notices is
just how vast this region is. Louisiana’s Gulf Coast winds for
hundreds of miles from Sabine Pass, Texas to Chandeleur Sound,
halfway across the southern border of Mississippi. The Mississippi
River Delta stretches like a giant three-toed turkey foot into the
Gulf of Mexico.

Everything down here happens on a grand scale.

This vastness – from the sheer expanse of the Gulf, to the
myriad islands, bays and bayous and the richest abundance of
natural resources found anywhere in North America – is both a
blessing and a curse. A human lifetime ago, Louisiana’s coastal
marshes covered some three million acres. Today, a third of those
acres are gone, swallowed up by the Gulf.

Over the course of the last century, a great tug-of war has
played out over this region and its resources. On the one hand,
far-sighted conservationists set aside much of the Gulf Coast in
national wildlife refuges, eight of them in Southeast Louisiana
alone. On the other hand, a growing nation developed this region as
fast as it could. We took advantage of its connection to the oceans
and turned New Orleans into a seaport that dispatches America’s
bounty to the rest of the world.

In the 1930s, we discovered gas and oil in the coastal zone. To
reach this mineral resource and extract it, the oil industry
dredged some 20,000 miles of canals in the heart of the coastal
marsh. Then, oil was discovered out in the Gulf, and in a couple
decades the world’s largest concentration of offshore oil rigs –
4,000 in all – grew like a steel forest. Until the Deepwater
Horizon disaster in April, how many Americans knew these rigs stand
in a mile of water and drill another five miles to reach the oil
and gas?

The Deepwater Horizon made us all aware of the size and scope of
the oil and gas operations here in the Gulf, but it also brought to
light an issue that had somehow escaped the nation’s attention
until now – the ongoing loss of wetland habitat that is rapidly
eating away Louisiana’s coastal marshes.

“This may well be the silver lining to the oil disaster,” says
Dale Humburg, chief biologist for Ducks Unlimited, here to meet
with media and staff from the National Wildlife Federation and tour
the coastal wetlands.

The scope of the loss is hard to fathom, even for local
inhabitants who have seen it happen before their eyes.

“We have lost 2,000 square miles in the last 70 years,” says
Pulitzer Prize-winning journalist Bob Marshall, a New Orleans
native who writes for the Times Picayune. “And we continue to lose
about 25 square miles per year, a football field every 40 minutes.
A delta that took nature 6,000 years to build is being erased in a
single human lifetime.”

How did this happen and what are the consequences?

To answer those questions, we need to look at the hydrology of
the Mississippi River Basin, which encompasses roughly the middle
third of the continent. Each spring, the Mississippi and its
tributaries carry sediment from mountain, plain and prairie to the
Gulf of Mexico. Historically, this sediment was dispersed through a
capillary-like network of bayous that spread out from the river’s
mouth. As the water slowed down, sediment settled out and literally
built the delta and its marshes.

People have lived along the river and in the delta for
centuries, rebuilding their homes and cities after each flood or
hurricane. In the 19th century, Americans began to build levees to
protect those cities. Then in the 1930s the U.S. Army Corps of
Engineers built a series of dams to control the flow of the
Mississippi and Missouri rivers and facilitate shipping. Those dams
and levees have two detrimental side effects their creators did not
anticipate – the dams hold back much of the marsh-building sediment
that once washed into the delta, and the levees channel the flow of
the Mississippi River out into the Gulf, bypassing the network of
shallow bayous that distributed that sediment.

Now, instead of continually rebuilding coastal marsh, that
sediment is flushed into deep water off the Continental Shelf,
where it has helped create an hypoxic or “dead” zone of about
10,000 square miles.

The combined effect of the canals and levees has allowed
saltwater from the Gulf to invade the freshwater marshes, killing
delicate freshwater vegetation – everything from submergent aquatic
plants like hydrilla and milfoil, to giant cypress trees. This
vegetation is what holds the sediment in place. When it dies, its
roots lose their grip on the soil, allowing rising tides and storms
to erode it away. This erosion occurs gradually, a little with
every tidal ebb and flow, and it occurs suddenly, with a hurricane
or other major weather event.

Historically, the coastal marshes sustained themselves,
rebuilding slowly and gradually extending the toe of land into the
Gulf. Aerial images from the 1930s compared with those from today
show how much has been lost and how rapidly that loss has
happened.

The tiny hamlet of Buras lies about halfway down the turkey’s
leg from New Orleans to Venice. This village has seen its share of
natural disasters. Thanks to Hurricanes Katrina and Rita, Ryan
Lambert’s Cajun Outfitters Lodge has been under 20 feet of water
twice since he built it in 2000. Like many natives here, Lambert
rebuilt his lodge and kept his business going. He and a team of 14
guides take anglers out after redfish and trout most of the year,
and ducks in the fall and winter. Each year, however, there is less
of his beloved marsh than the year before, fewer places where ducks
come to winter and redfish come to feed on shrimp.

As he idles his bay boat out of Buras Marina, Ryan Lambert tries
to show a group of visitors how much has been lost.

“It’s 6.8 miles from here to the Gulf,” Lambert says. “When I
started guiding here 30 years ago, it was solid marsh every bit as
good as what’s behind us. Now, except for those two little islands
there isn’t a blade of grass from here to the Gulf. Not only is the
marsh all gone, the water is four feet deep.”

Over the next three hours, Lambert motors across expanses of
open water. As if reading a list of fallen soldiers, he calls out
the names of the bays and bayous that still exist on older maps,
but are now lost forever to the saltwater: Grand Liard Bayou, Bay
Jacques, Scofield Bay, English Bayou. He points out some of the
damage to a bayou that a visitor can’t see.

“When that hole opened up, you could hardly get a boat through
it,” Lambert says. ” Now the whole corner is gone. Then the water
gets deeper and the saltwater intrudes.”

Further along, Lambert shows us an earthen levee and a concrete
wall that now cuts off a bayou from the marsh, stopping the natural
rebuilding and allowing erosion to accelerate.

“All the water that collects behind the levee from the rain, we
pump out right here through these big pipes,” he says. “But this is
a natural bayou that went right to the river. Indians used these
oak ridges for their villages. It would be so easy to open up these
natural waterways right to the river and let the natural waterways
disperse the sediments. Instead of using siphons, put the sediments
through the natural waterways that already exist. Open them all up
– that’s the only way we’re going to save it – let Mother Nature
save it.”

Lambert motors along a pipeline canal, pointing out shrimp boats
anchored in the marsh, temporarily abandoned by their owners who
will return and put them to work when and if the shrimp-fishing
season resumes. Tides and storm surges have rocked these boats back
and forth, crushing marsh vegetation and opening another hole for
saltwater to eat into the marsh.

To the untrained eye, one stretch of green marsh looks pretty
much like another, but Lambert points out the differences. There is
freshwater marsh, protected from the invading saltwater by a bayou
that brings freshwater from the river. This is a grocery store to
the millions of puddle ducks that will funnel down the Mississippi
Flyway to winter here, providing duck weed, wild peas and other
vegetation that will sustain them.

There is also brackish marsh – intermediate between fresh and
salt – that serves as a nursery for the young of many saltwater
species: redfish, speckled trout, even the offshore species like
tuna.

On the outside, there is salt marsh, the last toehold of land
between the coast and the Gulf. Here, three species of Roseau cane
– two non-native and one indigenous – are the only vegetation that
can thrive. The roseau’s long stems and deep roots keep the sod in
place, but they are no match for a hurricane’s winds and waves. In
some areas, there are hundreds of acres of Roseau. In others, there
are merely small clumps that the next storm will wash into the
Gulf.

The Louisiana coastal marsh is a dynamic system that for
centuries has survived and thrived. Now, thanks to a century of
intense development, a lack of understanding of how the system
works, and a national and regional political climate that turned a
blind eye to environmental concerns, all tempered no doubt by the
indifference fostered by an apparently unending abundance, this
region has reached a point where something must be done to reverse
the process before the marsh is all gone.

Next week in Part Three: Regaining Paradise – a look at what’s
at risk and efforts to restore the coastal wetlands.

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