Sea of Atlantis
The Future City of New Orleans
A characteristic lesson from the fall of Atlantis is that humans can manipulate matter. Furthermore, humans can appear to bend Nature to their needs. However, neither the Atlantean culture nor our own can control the laws of Nature.
To demonstrate that human control of nature is an illusion, look no further than the perceived permanence of the Old River Control Structure, 135
miles upriver from New Orleans, Louisiana. Atlantean elite labels and
slogans are often so audacious, that their unrealistic goals sound
heroic or mythical. Imagine the audacity of using poles stuck in the mud
to control the largest river in North America. In anticipation that
their designated mounds of earth would stay where expected, the Army
Core of Engineers (COE) named it a “river control structure”. Prefacing
that moniker, should be the word “temporary”.
After the experiences of Hurricane Katrina and the
2010 flooding in Pakistan, it is reasonable to believe that New Orleans
might yet experience simultaneous floods of each type. The scenario goes
like this:
- When a Katrinaesque hurricane makes landfall at New Orleans, resultant storm surge and overflow from Lake Pontchartrain floods much of the city.
- As the storm travels north, it stalls and dumps unprecedented rainfall on the Middle and Upper Mississippi River Valleys.
- When the resulting flood crests at the Old River Control Structure, catastrophic failure ensues, sending one uncontrolled torrent down the Mississippi River Channel and another down the Atchafalaya River.
- As an unprecedented flow reaches New Orleans, the city floods yet again, only this time there are few if any levees still standing to protect it.
In the aftermath of a simultaneous Katrina-style storm surge and a Pakistan-style river flood, New Orleans could well be unsalvageable.
After such a super flood, the Mississippi River Channel through New
Orleans would become a silt-clogged riverbed, rather than the deep
channel of today. Unless stakeholders plan now for decreased reliance on
river and port traffic for economic vitality, New Orleans faces the
possibility of a flood-induced economic collapse.
Have we learned our Atlantean lessons? For the most part, the answer is, “No”. We prefer the nostalgia of the French Quarter; a streetcar named Desire
and a wonderful cultural history to prudent post-Atlantean and
post-Katrina planning. Mythical thinking will not end global warming,
higher sea levels or stronger storm surges. Regardless of who or what
caused global warming, reputable scientists agree that future weather
trends include higher average surface temperatures. From Venice, Italy to Bangladesh, to the Seychelles Islands,
the accelerated pace of coastal and island flooding worldwide shows no
signs of abating. If the Greenland ice shelf melts away, we may not be
discussing the prospects of saving any of those places, as they may
already be slipping beneath the waves.
Since Katrina in 2005, the federal government has spent an estimated $125 billion
in and around New Orleans. As a citizenry, we should now determine how
much we plan to spend on any flood prone region. More important, what we
wish to accomplish with those funds? As long as
the option for rebuilding a full-sized, old style New Orleans is on the
table, the cost may well be too high to bear. Currently, few of the
local, state or federal stakeholders are willing to downscale their
ambitions. Instead, they attempt to resolve the issue with public
proclamations, featuring new and soon to be inadequate levees. Dubbed
“The Great Wall”, one new storm surge barrier reminds me of the original
Great Wall of China. Astronauts report that the original Great Wall is
the only manmade structure easily visible from the International Space Station.
History showed that those massive bulwarks did little to prevent
nomadic groups from entering the Chinese Empire. Likewise, the new Great
Walls will not fully protect New Orleans from category-five hurricanes.
Extensive dredging and reworking of the watercourses
throughout the Mississippi River Delta have made defending New Orleans
more difficult. After it snakes through the city, the Mississippi River
deposits almost none of its silt in
shallow water. Instead, the river rushes past New Orleans on a fast
trip to the Gulf of Mexico. Bypassing any remaining wetlands, the silt plunges deep into the Gulf.
On its descent to the seafloor, the silt releases a toxic mixture of
fertilizer and chemicals. Suspended in the water column above the silt
beds is a vast hypoxic dead zone. Not even bacteria can survive in its oxygen-depleted environment.
In June 2010, the federal government dedicated over $14 billion to rehabilitation of Louisiana wetlands. At the same time, rumor
had it that President Obama supported a redirection of the Mississippi
River as a mechanism for providing silt to those wetlands. To accomplish
that goal, he might order the COE to flip-flop the water delivery
ratios at the Old River Control Structure. New Orleans would henceforth
receive huge amounts of silt, but far less water. Concurrently, the
Atchafalaya River would take its place as the terminal distributary of
the Mississippi River. Upon settling downstream from New Orleans, the
newly redirected silt would naturally rebuild fisheries, bayous and
marshes. In turn, the larger wetlands would form a natural storm surge
barrier for the city.
Only the Mississippi River can discharge the silt
volume required to rebuild the wetlands. If humans or Nature can slow
the velocity of the river, soils from more than a dozen states might
begin to precipitate out near New Orleans. Only then would the river
become a useful tool for rebuilding the wetlands of the Mississippi
River Delta. If ever there was a good argument for letting Nature take
her course, this may be it.
As a cultural landmark and a great historical city, I
love New Orleans. Sadly, it has now become a poster child for Atlantean
mythical thinking. As a society, we must be willing to create an
infrastructure and investment strategy for New Orleans that has finite
goals and limits. What budgetary amount we agree upon is less important
than being realistic about our attempts to control Nature.
Once realism returns to the process, scientists and engineers can
combine efforts and create appropriate defenses for core locations and
critical functions throughout the region.
Although almost no one wants to hear it, New Orleans
should utilize its lowest lying and most vulnerable areas as storm
surge basins. After relocating low-income residents to safer areas, the
city could afford to sacrifice low-lying areas to flooding, while
protecting and preserving a more defensible city core. Ultimately, it
will be less expensive to provide a Brad Pitt House in a new
neighborhood for each low-lying family than to leave entire
neighborhoods in peril. Once the lowest lying residents move out, those
areas could become parks or urban farms. With no fulltime residents in harm’s way, the cost of future flood protection and reconstruction would be far lower.
Any legitimate plan for New Orleans must recognize the near inevitability of storm surge
and river related flooding. Even with a pragmatic plan, rather than a
political one, there is no guarantee that a great flood will not
inundate New Orleans. The strategy that I suggest would allow a smaller
city to survive longer than the current “full city” strategy, while
saving both money and the environment in the process.
By James McGillis at 01:43 PM | Environment | Comments (0) | Link
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