For 40 years, the Mississippi River Gulf Outlet (MRGO) has been reviled in New Orleans as a "hurricane highway." The U.S. Army Corps of Engineers dug it as a shortcut to the Port of New Orleans for deep-draft vessels, but it never attracted much traffic, and it destroyed more than 20,000 acres of nearby wetlands. But despite complaints from St. Bernard Parish, the Corps refused to close it and continued to spend $13 million a year dredging it.

Then Hurricane Katrina blasted up the Gulf Coast, buckling Corps levees and inundating St. Bernard Parish. One hydrodynamic model has concluded that the outlet helped amplify the height of Katrina's surge by three feet and doubled the velocity of the surge. Corps officials have declined to comment on the causes of their levee failures, saying they are waiting for the results of four investigations.

Now comes the New Orleans litigation firm of Maples & Kirwan, veterans of the asbestos and tobacco wars, with a class-action lawsuit filed this month against the United States in the U.S. Court of Federal Claims. The named plaintiffs are Rocco and Thomas Tommaseo, owners of a popular Italian restaurant in St. Bernard Parish, and Steven and Cynthia Bordelon, owners of a mobile home and RV repair shop, but attorney Stuart Kirwan said the firm has signed up hundreds of additional parish residents.

As a federal agency, the Corps enjoys "sovereign immunity" that should protect it against potential lawsuits over the design or construction of its levees. But Kirwan says the immunity should not extend to a navigation canal built for purely commercial purposes.

The suit argues that the creation of the outlet amounted to a public "taking" of private property, so flooded residents should be granted compensation under the Fifth Amendment.

-- Michael Grunwald

Here are some excerpts:

5. Construction of the MRGO started in 1958 and was completed in 1965. The construction of the MRGO was originally authorized to a depth of 36 feet, a surface width of 650 feet, and a bottom width of 500 feet. The 76-mile channel bisected the marshes of lower St. Bernard Parish and the shallow waters of Chandeleur Sound and cut through then existing marsh land which had acted as a natural barrier against hurricane winds and storm surge.

6. The creation of the MRGO allowed salt water from the Gulf of Mexico to flow further inland into the marshes of St. Bernard Parish, thereby killing plants and vegetation which had served to hold land and soil in place. Without the aforesaid plants and vegetation, the land and soil eroded, leading to a widening of the MRGO beyond the dimensions originally authorized.

9. The wetland loss and deterioration from the MRGO have allowed for expanded tidal amplitude and duration, increasing the flooding risk to interior portions of St. Bernard Parish and providing a direct line of access for hurricane-related storm surge to reach St. Bernard Parish. This presented a known threat of flooding in the event of a severe hurricane such as Hurricanes Katrina and Rita, as described herein below.

10. In the fall of 1998, the St. Bernard Parish Council unanimously adopted a resolution calling for the closure of the MRGO because of the flooding threat to St. Bernard Parish.

11. In 1958, the United States, through the Department of the Interior, published a report warning that "excavation of the (MRGO) could result in major ecological change with widespread and severe ecological consequences."

13. On or about August 29, 2005, Hurricane Katrina struck the Louisiana and Mississippi Gulf Coast, pushing a storm surge through the MRGO. The storm surge overwhelmed the levee system between the MRGO and plaintiffs' property in St. Bernard Parish resulting in massive flooding and the destruction of plaintiffs' property. This flooding was a natural and direct consequence of the creation of the MRGO and the continued operation, maintenance and dredging thereof by the United States.

27. WHEREFORE, the premises considered, plaintiffs pray

(a) that this matter be maintained and certified as a class action on behalf of all those persons residing, owning property and/or engaging in commercial enterprises in St. Bernard Parish, Louisiana, which property was taken by the United States for a public purpose through the construction and continued operation, maintenance and dredging of the Mississippi River Gulf Outlet.

(b) for judgment in their favor individually and on behalf of all persons similarly situated and against the United States of America finding that plaintiffs' property as well as the property of all persons similarly situated has been taken for a public purpose entitling plaintiffs, and all persons similarly situated, to just compensation in accordance with Amendment V of the U.S. Constitution in the amount of $5,000,000,000.

The Mississippi River Gulf Outlet was dug by the U.S. Army Corps of Engineers as a shortcut to the Port of New Orleans. Residents say the project led to flooding.