Georgia Port officials and a South Carolina agency agreed Wednesday to a proposed settlement seeking to end lawsuits between the states over a $652 million plan to deepen the shipping channel to the Port of Savannah, though other parties also must accept the compromise before it can take effect.

A settlement would potentially clear two big obstacles Georgia officials have faced in trying to deepen more than 30 miles of the Savannah River. They want to make room for supersized cargo ships to reach the nation’s fourth-busiest container port in Savannah after the Panama Canal finishes a major expansion in 2015.

A deal would settle disputes with state officials in South Carolina, which shares the river with Georgia and operates a major competing port in Charleston. It also would settle with conservation groups that sued in U.S. District Court, arguing that allowing the Army Corps of Engineers to deepen the Savannah harbor to 47 from 42 feet would cause unacceptable environmental harm.

“This settlement will bring to an end the immediate dispute between Georgia and South Carolina and allow the corps to proceed,” Jamie McCurry, government relations officer for the Georgia Ports Authority, told the agency’s board members Wednesday before they voted to approve the deal.

He noted that it also would settle the suits by three groups represented by the Southern Environmental Law Center.

The Savannah River Maritime Commission, a South Carolina state agency involved in the lawsuits, also met Wednesday and agreed to sign the settlement, said Dean Moss, chairman. Neither party would comment on details, pending the deal’s approval by the conservation groups and the Army Corps. The settlement would then go to a federal judge for final approval.

Copies of the proposed settlement were given to reporters. Most of the terms would require the Army Corps to perform additional environmental monitoring and mitigation. The Georgia Ports Authority would pay more than $25 million for extra conservation efforts and transfer ownership of 2,000 acres of salt marsh to state officials in South Carolina.

The settlement also would give South Carolina agencies and environmental groups a chance to back out of the entire deal and return to court if a test run of equipment designed to replenish oxygen in the water fails to work.

Chris DeScherer, an attorney for the Southern Environmental Law Center in Charleston, declined to comment Wednesday. Billy Birdwell, a spokesman for the Army Corps in Savannah, said in an email that the agency might have an announcement in “a few days.”

“What we can tell you is that all parties did their best to negotiate a reasonable settlement,” Birdwell said.