In particular, the shared waterway that has long been dominated by Georgia is drawing new attention from its neighbor -- especially on the coast, where Georgia's $600 million plan to deepen Savannah Harbor is creating friction with Palmetto State policymakers.
Observers say it is a long overdue sign of the times that will have repercussions for communities far upstream, including Augusta.
"The issues with the river are very complex, sciencewise, and there are significant challenges ahead politically, too," said Braye Boardman, who heads The Nature Conservancy's Georgia chapter and has served since 2005 on a committee created by former Gov. Sonny Perdue to work with South Carolina on issues involving the river.
The Savannah Harbor project, which includes dredging 26 miles of the river to increase its depth from 42 to 48 feet, is vital to accommodating a new generation of mammoth cargo ships that will begin using the East Coast when an expanded Panama Canal opens in 2014, according to Georgia officials.
In Atlanta, Gov. Nathan Deal was quick to point out the river's economic value soon after taking office.
"There is no more important public works project for the competitiveness of our entire region," he told lawmakers during his State of the State address.
In South Carolina, there is already a proposal to expand the competing port of Charleston -- a move new Gov. Nikki Haley has said is critical to keeping her state competitive.
"You now have a governor who does not like to lose," she said during a speech to a Charleston maritime group. "Georgia has had their way with us for way too long, and I don't have the patience to let it happen anymore."
Last week, South Carolina's Legislature passed a resolution opposing the Savannah Harbor project, asserting it will fight any plan "that does not provide mutual economic benefits" to South Carolina."
In addition to environmental concerns, state officials argue that Georgia's plan would prevent progress on a bi-state Jasper Ocean Terminal proposed for 1,600 acres on South Carolina's side of the river.
Has Georgia "had its way" with South Carolina? In many ways it has, especially where industry-laden Augusta is concerned.
"The next big thing to tackle is an allocation plan," Boardman said. "Georgia currently has more than 95 percent of the river's wasteload allocation and South Carolina has 5 percent."
That means industries that want to move to South Carolina might not be able to get permits for their wastewater -- in part because Georgia has already filled the river with as much waste as it can safely absorb. Similarly, larger metro areas such as Augusta and Savannah use bigger shares of drinking water.
"The river is supposed to be jointly owned and jointly managed," Boardman said. "We want to start sharing it before we end up fighting over it."
Georgia is also involved in a water war with Florida and Alabama, exacerbated in recent years by a federal court ruling that Atlanta might have to give up Lake Lanier as a major drinking water source.
Neither state wants to wage such battles over the Savannah.
"It is Georgia's hope that the Savannah Harbor project will have no impact on our relationship with South Carolina regarding shared water resources in the Savannah River," said Stephanie Mayfield, Deal's press secretary. "We have worked very well with South Carolina on other high-profile issues."
South Carolina residents, she added, account for 40 percent of the jobs at Savannah Harbor, so its expansion would benefit everyone.
"It is a partnership between the two states," she said. "There is no wall along the Savannah River that stops economic development from crossing over the two states."
Despite those assurances, environmental groups fear the divisions over the river's coastal region will gradually work their way upstream.
"The great concern right now is the relationship between South Carolina and Georgia in river management," said Tonya Bonitatibus, the executive director of the Savannah Riverkeeper environmental group. "The harbor is becoming the centerpiece of that argument, and the argument is growing."
The lower river already suffers from low oxygen levels, which has led Georgia's Environmental Protection Division to place wastewater permit renewals in the Augusta area on indefinite hold pending new water quality regulations. If water quality downstream continues to deteriorate, Augusta could face further restrictions, as could communities in South Carolina.
One of the Riverkeeper's main initiatives this year is to promote the concept that every stakeholder along the basin is entitled to an equal share of the flow.
"That means the lakes aren't being kept too full, and that Savannah isn't receiving an excess of water all the way downstream," Bonitatibus said, noting that the river and its resources -- and the demands on those resources -- vary widely along the Savannah's long border.
In the upper reaches, where the river is backed into dams and reservoirs, the focus is often on water levels, real estate values and the recreation industry.
The central river area near Augusta includes factories and cities that need drinking water and a place to dump treated wastewater. The lower river's vast swamps are home to vanishing cypress forests and other natural areas, and coastal estuaries are critical to shrimp and other species.
Bonitatibus said it is a challenge for stakeholders to share the river's flow. Lake-area advocates, for example, have opposed releasing more water downstream during droughts to prevent saltwater intrusion on the coast.
Conflicts between upstream and downstream users are inevitable, Bonitatibus said, but the bigger challenge is how the states will compete for a finite set of resources.
"Are those resources being shared equitably? I'm afraid the answer is no," she said. "Right now the only remedy is exactly what we are doing, trying to keep everyone talking and keeping temperatures from flaring. That way we don't end up in a Georgia-Florida-Alabama kind of fight."
PORTS OF CONTENTION
The Savannah Harbor project is a plan for the port of Savannah to deepen the river from 42 feet to 48 feet for 26 miles. Georgia contends that the project is needed for the new generation of cargo ships.
South Carolina Gov. Nikki Haley says her state's plan to expand the port of Charleston is a critical step to remain competitive.