Coastal restoration project is ill-advised, St. Bernard residents say
By Mark Schleifstein, The Times-Picayune
April 20, 2010, 9:55PM
The Mississippi River-Gulf Outlet and Intracoastal Waterway, looking west toward New Orleans, were photographed in August 2009.Plans by the Army Corps of Engineers to build a freshwater diversion across an open stretch of land in St. Bernard Parish to restore wetlands and cypress forest areas in New Orleans, along the closed Mississippi River-Gulf Outlet and Lake Borgne ran into criticism from St. Bernard residents at a public hearing Tuesday night.
"This is not going to build any land, and a freshwater diversion is not going to re-create the Biloxi marsh," said Robert Campo of Campo's Shell Beach Marina. "The first line of defense, people, is rebuilding the damn barrier islands.
"This is going to screw up recreational fishing, going to screw up our marina," he said.
The new diversion would be part of the Mississippi River-Gulf Outlet Ecosystem Restoration Project, authorized by Congress to restore wetlands damaged during the operation of the MR-GO until it was closed last year.
Corps project manager Greg Miller explained to an audience of about 75 at the Holy Angels Convent in New Orleans that the diversion would be designed to reduce salinity throughout the 6,000-mile area stretching from Lake Maurepas to Gulfport, Miss., to the mouth of the Mississippi River.
However, the diversion will be of a fairly small amount of water -- only 1,000 cubic feet per second for 11 months of the year and a pulse of 7,000 cubic feet per second during May.
Salinity levels would be restored to pre-MR-GO levels of about 15 parts per thousand at the outer edge of the Biloxi marshes and about 5 parts per thousand in northwestern Lake Borgne, according to computer modeling conducted by the corps, Miller said.
Since the MR-GO was built, much saltier water had reached as far west as Lake Borgne, exacerbating wetlands loss and resulting in more saltwater species being caught in what were once freshwater areas.
If successful, the diversion canal would move water from the Mississippi River just south of Meraux toward Lake Borgne, with some of the water funneled into the Central Wetlands Unit, sandwiched between the levee along the Gulf Intracoastal Waterway and the MR-GO and the populated areas of the Lower 9th Ward, Arabi and Chalmette.
That area was a mix of freshwater wetland and cypress swamp before the MR-GO was built. Construction of the shipping shortcut from the Gulf of Mexico to the Industrial Canal in New Orleans killed much of the cypress, The corps plan would include moving sediment dredged from the Mississippi or the GIWW into the Central Wetlands Unit to provide a platform for three sections of restored cypress and a large border of freshwater wetland grasses.
The plan calls for creating about 9,500 acres of cypress swamp in that area.
Sediment also would be dredged from the center of Lake Borgne, for use in rebuilding wetlands along the lake's shoreline, including the Golden Triangle at the junction of the MR-GO and the GIWW.
During construction, the project would require temporary bypasses to be built for St. Bernard Highway and Judge Perez Highway and a railroad track, with construction expected to take between 2 ½ and 3 years.
The corps hopes to release a draft of the study and a draft environmental impact statement by the end of May, Miller said.
More information about the project is available on the Web atwww.mrgo.gov.
Mark Schleifstein can be reached at mschleifstein@timespicayune.com or 504.826.3327.
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