The $706 million deepening of Savannah's harbor and waterway is set to begin in September - about three months earlier than expected.

The U.S. Army Corps of Engineers and Gov. Nathan Deal's office said Friday that workers will begin to dredge the outer edge of the 38-mile channel on Sept. 7 instead of December, when the project

.

The agency also announced it has granted a nearly $100 million contract to a Florida company to pump oxygen into the Savannah River harbor, which already suffers from low oxygen levels. The work is part of an out-of-court settlement with conservationists and considered crucial to offset the project's environmental impact, which is expected to lead to a further drop in oxygen levels that could endanger marine life.

Other work to set the stage for the dredging is well underway. Deal's office said a key section of a weighty ironclad vessel called the CSS Georgia that defended the city during the Civil War is to be raised from the river's depths on Saturday. That work will bring up a bulky casemate, which housed the boat's artillery pieces, that remains nestled deep beneath the water's surface.

Deal said the developments are a sign that the project to deepen Savannah's harbor and waterway is shifting into high gear. The dredging project, which would deepen Savannah's harbor and waterway from 42 feet to 47 feet, has been in the works for more than a decade and united Georgia politicians of all stripes.

The port and its cousin in Brunswick support 100,000 metro Atlanta jobs and, according to a University of Georgia study, constitute a $39 billion economic boost for the state. State leaders argue that deepening the waterway would allow bigger ships coming through the expanded Panama Canal to dock in Savannah and keep the port competitive with rivals up and down the coast.