Ruling in a nearly decade-old lawsuit, a judge in Washington said Friday that the federal government is responsible for some of the catastrophic flooding that followed Hurricane Katrina and other storms — flooding blamed on a now-closed navigation channel.

Judge Susan Braden, of the U.S. Court of Federal Claims in Washington, said the flooding was, in effect, a “taking” of property under the Fifth Amendment, for which the plaintiffs must be compensated.

How much the government will have to pay in damages is unclear. Braden set a conference for next Wednesday in New Orleans to determine whether an agreement can be reached to have damages assessed by a mediator.

Also unclear is how many people will benefit. There are a handful of plaintiffs, but attorneys were seeking class-action status that could mean many people in St. Bernard Parish and New Orleans’ Lower 9th Ward. The judge’s ruling did not address whether class-action status would be granted.

Friday’s ruling came in an October 2005 lawsuit filed by the government of St. Bernard Parish — adjacent to New Orleans — and several property owners. It focuses on the now-closed Mississippi River Gulf Outlet — a navigation canal built by the U.S. Army Corps of Engineers and blamed by many for flooding in St. Bernard and the Lower 9th after Katrina.

“It’s great news for St. Bernard Parish,” Parish Council member George Cavignac said. He declined to speculate on possible monetary damages.

“Now that this important decision regarding the government’s liability has been issued, we look forward to further proceedings to resolve this case and to ensure that property owners in St. Bernard Parish and the Lower 9th Ward obtain the relief to which they are entitled under our Constitution,” said Carlos Zelaya, a lead attorney in the case.

The suit says the construction, dredging and operation of the navigation canal, known in south Louisiana as “Mr. Go,” contributed to conditions that led to catastrophic flooding during Hurricane Katrina in August 2005, Hurricane Rita weeks later and other storms. In effect, the suit argued, the damage caused by the flooding was an illegal taking of private property by the federal government without adequate compensation.

Braden agreed, ruling that the Corps’ “construction, expansions, operation, and failure to maintain the MR-GO” led to storm surge and flooding that amounted to “a temporary taking under the Fifth Amendment to the United States Constitution.”

The canal was authorized by Congress in 1956 as a shortcut from the Mississippi River to the Gulf of Mexico and was completed years later. It was shut down in 2009.

Numerous other lawsuits filed against the federal government over Katrina-related flooding have failed.

A string of court rulings insulated the federal government from liability for billions of dollars in flood damage that many residents and business owners have blamed on the Corps’ design, construction and maintenance of levees and floodwalls, as well as the MRGO.

Representatives of the U.S. Department of Justice and the Corps did not immediately respond to requests for comment.

Braden said Wednesday’s meeting will determine whether the parties in the case can agree to have damages assessed “by a knowledgeable and accomplished mediator — and in short order.” The conference was scheduled earlier this week, and Justice Department lawyers had sought to delay it even before Friday’s ruling was posted.

Braden’s order appeared to advise the Corps and the Justice Department against an appeal. She referenced a Supreme Court decision in an unrelated but similar case involving flooding and said, “further litigation in this matter is not in the interest of the Army Corps and will not serve the interests of justice. It is time for this final chapter of the MR-GO story to come to an end.”