[StBernard] Wetlands restoration urged in wake of MR-GO damage

[Westley Annis]

Wetlands restoration urged in wake of MR-GO damage
By Mark Schleifstein, The Times-Picayune 
April 26, 2010, 9:00AM

The Army Corps of Engineers should recommend the construction of a series of
wetlands restoration projects be fast-tracked to mitigate the 50 years of
damage caused by the Mississippi River-Gulf Outlet to the environment and
New Orleans area communities, say representatives of 17 environmental and
civic groups that make up the MRGO Must Go Coalition.

Though the shipping short-cut between the Gulf of Mexico and the Industrial
Canal -- blamed by many for exacerbating flooding after Hurricane Katrina --
has been blocked by a massive rock dam, debate continues over how to remedy
the erosion, salt-water intrusion and habitat loss caused by the channel.

The coalition is publishing its recommendations Tuesday in a new report
titled, "Mister Go Isn't Gone Yet: Creating Community and Environmental
Resiliency in the Wake of a Man-Made Catastrophe."

Corps and state officials must quickly come to agreement on who will pay for
the restoration efforts, which could cost more than $1 billion, said Juanita
Constible, a spokeswoman for the National Wildlife Foundation's Louisiana
operations. The coalition supports state efforts to require the restoration
to be financed with 100 percent federal money, rather than the traditional
65 percent federal and 35 percent state split.

State officials contend that provisions in agreements between the state and
federal government on building freshwater diversion projects to reverse
MR-GO damage, and in legislation requiring the corps to develop a
restoration plan when Congress deauthorized the channel, require the corps
to pay for all restoration costs.

The coalition report is aimed at reinforcing recommendations the group has
made as the corps completes work on its own MRGO Ecosystem Restoration
Study, due to be released at the end of May.

One of the top priorities, according to the coalition report, is
construction of a "Violet" diversion, a diversion of freshwater from the
Mississippi River either through the existing Violet diversion or through
another location running into Lake Borgne. 


The corps has proposed diverting an average 1,000 cubic feet of water per
second most of the year, with a four-week period in the spring when as much
as 7,000 feet per second would be pumped.

The coalition warns that might not be enough water, as the corps design
assumes that two other diversions would be built upriver at Blind River and
the Hope Canal to add water to Lake Maurepas, which would then flow through
Lake Pontchartrain into Lake Borgne. Only when the water from those
diversions were added to the Violet project would the targets for salt in
waters on the eastern side of the Mississippi and in Lake Borgne be met, and
there's no guarantee they'd be finished for years, the report said.

Keeping salinity levels low is important to allow vegetation to take root
and thrive, holding soils in place and reducing erosion.

Thus, the Violet diversion should be built to allow a maximum flow of 7,500
to 15,000 cubic feet per second, and even higher flows in drought years, a
target that is likely to draw the ire of oyster leaseholders and shrimpers
that rely on existing salt levels in the area's waters.

The group also proposes speeding plans to rebuild wetlands and cypress
forest in the Central Wetlands, an area within the levee system bounded by
the Gulf Intracoastal Waterway, the MR-GO, and the populated communities of
the Lower 9th Ward, Arabi and Chalmette. 

Restoration of a healthy cypress forest and wetlands in the area, even
though within the main hurricane levee system, would provide additional
protection from winds and surge to those neighborhoods, and provide fishing
and recreational opportunities to residents.

"Perhaps most importantly, the Central Wetlands could serve as an
easily-accessible demonstration of what restoration can accomplish, engaging
both citizens and decision makers from around the country in the future of
coastal Louisiana," the report said. 


The report also recommends that the eroded, straight-line path of the MR-GO
be re-engineered to constrict the size of the channel and to restore its
banklines. Narrowing the channel would reduce the chance that hurricane
winds could cause surge and waves to rise higher in the existing,
still-widening water body.

National Audubon Society coastal scientist Paul Kemp, who served on the Team
Louisiana forensic investigation group that studied the reasons why levees
failed during Hurricane Katrina for the state Department of Transportation
and Development, said recent modeling has shown that the MR-GO channel
caused surge and waves to be higher along St. Bernard levees during Katrina
because of such a regeneration process.

The report also recommends sustaining three important "land bridges" -- wide
sections of land and wetlands along the shorelines of Lake Borgne, in
eastern New Orleans stretching towards St. Tammany Parish across the bottom
of Lake Pontchartrain, and the Biloxi Marshes in easternmost St. Bernard
Parish.

The report recommends re-establishment of oyster barrier reefs along each of
the land bridges, rather than a reliance on rock or concrete to reduce the
effects of waves. 


Rebuilding several miles of the Bayou la Loutre ridge, basically an
extension of the new dam that closes the MR-GO at its southern end, is
another goal of the report.

The final recommendation is to rebuild the Gosier Barrier Island chain,
which is the southernmost segments of the Chandeleur Island chain, and were
almost washed away by Katrina. 

The MR-GO's channel cut through the southern end of the Gosier islands and
disrupted the movement of sand from those two islands to Breton Island to
the south. 

The report says that while most of the Chandeleurs are too far away to blame
the MR-GO on their rapid disappearance, the closer islands should be
restored to provide additional storm and hurricane surge protection to
interior wetlands. 

The full report is available on the Web at http://www.mrgomustgo.org/.