“This protective buffer took 6,000 years to form,” the state board that oversees flood-protection efforts for much of the New Orleans area argued in court filings, adding that “it has been brought to the brink of destruction over the course of a single human lifetime.”

The suit, filed in civil district court in New Orleans by the board of the Southeast Louisiana Flood Protection Authority-East, argues that the energy companies, including BP and Exxon Mobil, should be held responsible for fixing damage done by cutting thousands of miles of oil and gas access and pipeline canals through the wetlands. It alleges that the network functioned “as a mercilessly efficient, continuously expanding system of ecological destruction,” killing vegetation, eroding soil and allowing salt water into freshwater areas.

“What remains of these coastal lands is so seriously diseased that if nothing is done, it will slip into the Gulf of Mexico by the end of this century, if not sooner,” the filing stated.

A spokeswoman for BP said the company would have no comment. A spokesman for Exxon Mobil said the company had no comment at this time.

Gladstone N. Jones III, a lawyer for the flood protection authority board, said the plaintiffs were seeking damages equal to “many billions of dollars. Many, many billions of dollars.”

Mr. Jones acknowledged that the government, which has strong protection against lawsuits, might bear some responsibility for the loss of wetlands. But he noted that Washington had spent billions on repairing and strengthening hurricane defenses since the system built by the Army Corps of Engineers failed after Hurricane Katrina in 2005. By taking the companies to court, he said, “we want them to come and pay their fair share.”

The role of the industry is well documented in scientific studies and official reports. In calling for remediation efforts, a 2012 report by the state’s Coastal Protection and Restoration Authority stated, “Dredging canals for oil and gas exploration and pipelines provided our nation with critical energy supplies, but these activities also took a toll on the landscape, weakening marshes and allowing salt water to spread higher into coastal basins.”

The suit argues that the environmental buffer serves as an essential protection against storms by softening the blow of any incoming hurricane before it gets to the line of levees, flood walls, and gates and pumps maintained and operated by the board. Losing the “natural first line of defense against flooding” means that the levee system is “left bare and ill-suited to safeguard south Louisiana,” the lawsuit says.

The “unnatural threat” caused by exploration, it states, “imperils the region’s ecology and its people’s way of life — in short, its very existence.”

John M. Barry, an author and a member of the flood protection authority board, noted that there were other causes of coastal wetlands loss, including decisions by the Corps of Engineers over the decades to design navigation and flood control systems for the Mississippi River that kept its waters from delivering the sediment that once nourished the wetlands. Still, he said, “we just want them to fix what they broke.”

The lawsuit relies on well-established legal theories of negligence and nuisance, as well as elements of law more particular to the Louisiana Civil Code, including “servitude of drain,” which relates to changing patterns of water flow and drainage across the Bayou State. Even though the industry has been producing oil and gas for 100 years, because the damage is continuing to occur, the board argues, the statute of limitations should not apply.

Walter Olson, a Cato Institute expert on litigation who often expresses skepticism about civil litigation, said that he could not comment extensively without seeing the filing, but that “it sounds like the sort of thing you couldn’t dismiss out of hand.” He said some environmental lawsuits, like one against power companies over the effects of climate change on sea-level rise and its effect on the Alaskan town of Kivalina, incorporate creative legal arguments that may not stand up in court. “It’s not Kivalina,” he said, if the plaintiffs can point to specific people or entities causing specific damage. He added that proving causation in court, however, “can be a big headache.”

The state official overseeing coastal management sounded a skeptical note. The official, Garret Graves, chairman of Louisiana’s Coastal Protection and Restoration Authority, issued a statement saying that while he and his colleagues had not yet read the lawsuit and could not comment on its merits, “the best way to direct oil and gas company revenues into our coast is through revenue sharing from offshore energy production” through laws like the Gulf of Mexico Energy Security Act of 2006. That law directs a portion of federal income from offshore oil and gas exploration and production into coastal restoration and other environmental projects.

“We are encouraged by recent efforts in Congress” to increase those funds, Mr. Graves said, adding, “More needs to be done.”

No other state agencies have joined the lawsuit, and Mr. Barry said that during preparation of the suit, his board had not discussed the case with other levee boards. The politically powerful oil and gas industries might bring pressure to bear on others who might be inclined to join, Mr. Jones said, but now that the case has been filed, “it really raises the question that’s going to be asked at a whole lot of boards across southern Louisiana: Can we really afford not to do this?”

This article has been revised to reflect the following correction:

Correction: July 24, 2013

An earlier version of this article misspelled the given name of the chairman of Louisiana’s Coastal Protection and Restoration Authority. He is Garret Graves, not Garrett.

Article source: http://www.nytimes.com/2013/07/25/us/louisiana-agency-to-sue-energy-companies-for-wetland-damage.html?partner=rss&emc=rss