Georgia state leaders are trying to push the project ahead and get federal backing. Gov. Nathan Deal will tour the Savannah Port with U.S. Secretary of Transportation Ray LaHood and Atlanta Mayor Kasim Reed.
The group is touring Gulfstream Aerospace Corp. and the Port of Savannah.
The visit comes after an environmental group said an approval by a South Carolina health agency to dredging the Savannah River is invalid.
South Carolina's Department of Health and Environment Control gave the thumbs up to a permit for deepening Savannah's harbor, but the Savannah River Maritime Commission says that approval is invalid.
South Carolina state Sen. Larry Grooms is on the commission and chairs the state transportation committee. He said the decision means the case is most likely headed to court.
Officials say if Savannah's harbor isn't deepened, larger cargo ships going into service over the next few years won't be able to navigate the shallow waters.