(CNN) -- Missouri's attorney general turned to a federal court Tuesday to stop a federal plan to blow a levee to ease pressure on the flood-engorged Mississippi River.
The U.S. Army Corps of Engineers plan would flood more than 130,000 evacuated acres in southeastern Missouri, much of it in Mississippi County, said Attorney General Chris Koster.
"The flooding would leave a layer of silt on the farmland that could take as much as a generation to clear, causing significant injury to the quality of the farmland for many years," Koster said in a statement about the lawsuit.
James Pogue, chief spokesman in the Corps' Memphis office, said the Birds Point-New Madrid Floodway is a "safety valve" in the current crisis.
"This allows us to do what nature will do anyway, (but) in a controlled system," he said.
Birds Point is about 140 miles south of St. Louis. The floodway is about 35 miles from north to south and is four to 12 miles wide.
Maj. Gen. Michael Walsh ordered barges to be moved north on the river to prepare for the levee breach, Pogue said. "The decision was to move forward with the plan."
The Corps, which has authority over flood control, will make a final decision before the barges and teams get to work at Birds Point, he said. Reports indicate another meeting may occur Wednesday.
The river could crest in that area by Friday or over the weekend.
Koster argues the Corps is trying to protect Cairo, Illinois, downstream. Pogue said several communities along the river are in peril if nothing is done.
Koster also said a law requiring such action is unclear on whether the Corps has the authority to make a decision to detonate the levee.
About 100 families live in the floodway, which has not seen such use since 1937. Federal officials say the families have known of easements and legal rights the government has for flood control.
Not all the acreage will necessarily be covered by water, Pogue said, adding the farmland could be flooded anyway because of related rain and a backup of the Mississippi River.
Missouri Gov. Jay Nixon and U.S. Sen. Claire McCaskill have expressed their concern.
The latter, in a statement, said the intentional breach "could jeopardize the livelihood of countless Missouri families."
Mississippi County deputies are patrolling the levee to keep unauthorized persons away, state officials said.