(CN) - The 5th Circuit upheld a lower court's dismissal of a class action seeking to hold 32 federal contractors liable for flood damage linked to the dredging of the Mississippi River-Gulf Outlet shipping canal before Hurricane Katrina.
The three-judge panel in New Orleans backed a federal judge's decision to dismiss the 2006 class action against the United States and 32 dredging companies.
The plaintiffs claimed that the dredging damaged wetlands, "created an environmental disaster," and "dramatically increased the region's vulnerability to hurricanes and tropical surges."
Specifically, they said the dredging amplified the storm surge during Hurricane Katrina.
However, the district court found that the contractors were protected by government-contractor immunity, and the 5th Circuit panel agreed.
"These allegations attack Congress' policy of creating and maintaining the MGRO, not any separate act of negligence by the Contractor Defendants," Judge Priscilla Owen wrote.
The plaintiffs' remaining claims - that the lower court should have let them amend their complaint or conduct discovery - as being "without merit" or "harmless error," the court concluded.
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