Geography Reference
In-Depth Information
MRGO, the river deviation at Violet (St Bernard Parish) must supply freshwater and
sedimentation through Bayou La Loutre to sustain the Biloxi marches wetlands on
the eastern side of Lake Borgne. Downstream, the channeling of river water at
Caernarvon in Plaquemines Parish feeds the wetlands located on the east side of the
Mississippi delta. Several other diversions will be opened downriver in Plaquemines
Parish to save the area's marshes. Other ambitious operations are planned, such as
the construction of a new levee alignment and a floodgate at the entrance of the
Intracoastal Waterway near Paris Road, and eventually another floodgate at Rigolets
Pass (part of the Lake Pontchartrain Barrier Plan). If these plans materialize, the
salt-water gain on New Orleans observed in the 20th century could be reversed, and
the Mississippi Delta saved. The protection of New Orleans against storm surges
would no longer be based solely on the structural protections of the HPS, but also on
restoration of the wetland buffer. This policy falls within the framework of a
comprehensive regional development project, released in May 2007 and named
Louisiana Speaks. The plan represents a significant breakthrough in terms of
territorial governance by addressing the inter-parish differences that paralyzed New
Orleans metropolitan governance. According to a 2006 survey, 93% of the
population residing in Louisiana approved the plan for the preservation and
restoration of coastal wetlands. Of the respondents, 88% accepted the idea that
reducing risks may take precedence over collective property rights, and 81% wanted
to change the model for land use and development. These findings enable the
authors of the regional project Louisiana Speaks to promote a prospective outline in
the spirit of New Urbanism, giving priority to the densification of existing urban
spaces while advocating a public transit orientation over new road investment. In the
context of the southern United States, it is a cultural revolution!
The question remains as to whether these plans go far enough to meet the
challenge of climate change. Models project a possible rise in sea levels by 0.6
meters over the course of the twenty-first century. Most of the Mississippi delta is
below this altitude and is affected by subsidence that significantly accelerates the
rising relative sea level. Southern Louisiana is in a position to become the new
Netherlands and state leadership has intensely studied the Dutch model to try to
preserve their territory. In Louisiana, mankind is now engaged in a competition with
the sea and New Orleans is more than ever sailing in dangerous waters. In a more
general sense, the question of rising sea levels threatens all of coastal America.
What should be protected and at what price? There are three possible solutions.
Structural protection should consist of building levees similar to the HPS. The
rise in sea level implies regular reassessments of risk and the regular reinforcement
of levees and pumping systems. The reinforcement of structural protections, such as
the HPS, by 2011 is essential for the protection of big cities such as New Orleans or
