Tennessee legislators re-pelled "Georgia's heinous assault" on their state's sovereignty this month when the House voted unanimously to oppose Georgia's attempt to adjust the border between the states.

Unfazed, Georgia officials vowed to take Tennessee to the U.S. Supreme Court if necessary to remedy the 190-year-old border dispute and, in the process, gain access to the bountiful Tennessee River to slake North Georgia's drought.

Hyosub Shin/AJC/ (ENLARGE)

n 1818, a mathematician at UGA helped establish the Georgia-Tennesee border. It's largely accepted that the boundary is a mile below where Congress originally intended it to be. The challenge to move the border a mile north so that Georgia touches the drought-busting Tennessee River.

• Photos: A shallow Lake Lanier can be hazardous DEALING WITH THE DROUGHT: • Can I water? Here are the rules • 10 tips to save water • Map: Heavy demands on our water RELATED: Georgia's hopes fading for reversing water ruling  Southeast must adapt for drought, report says  Lawn sprinklers can create icy roads: Turn them off  Lake Lanier to hold more water after feds decision  Drought saps lakes, tightens grip on north Georgia  • More on coping with the drought

Georgia, though, could launch another legal attack. Federal land — not controlled by Tennessee — lies between Georgia and the river. The Tennessee Valley Authority, a federal agency that manages the river, owns the half-mile slice of largely untrammeled property separating Dade County, Ga., from the river.

TVA policy allows adjacent landowners to cross its property to reach the Tennessee River. Georgia, conceivably, could bypass a spat with the state by dealing directly with the federal government.

"We have a strong argument to the entire disputed area, but we have a stronger argument — the strongest — for the areas that are federal land," said Atlanta attorney Brad Carver, who has been advising Georgia legislators on possible legal tactics. "The state is going to have a lot of different strategies to look at."

Precedents on each side

There's little dispute that the border is wrong. Congress created the state of Tennessee in 1796, establishing its border with Georgia at the 35th parallel.

In 1818, a mathematician marked the boundary. Eight years later, James Camak admitted his error. Today, 51 square miles — Chattanooga suburbs, a portion of Lookout Mountain, national forests, TVA land and a bend of the river — fall within the disputed territory.

The 35th parallel lies 1.1 miles north of the current border. Georgia legislators want Tennessee to accept the original border so North Georgia could readily access hundreds of millions of gallons of Tennessee River water daily.

"I am more concerned about securing riparian [water] rights to the Tennessee River than obtaining the entire disputed area," said Sen. David Shafer (R-Duluth), whose SR 822 was unanimously approved by the Georgia Senate last month.

The joint resolutions (HR 1206 in the House) call on Gov. Sonny Perdue to begin border talks with Tennessee Gov. Phil Bredesen and to establish a joint boundary commission to resurvey the border by January.

Tennessee dismisses plans for a boundary commission. North-of-the-border lawyers cite Supreme Court rulings on "adverse possession" — Georgia, essentially, abandoned any claim by not contesting ownership for 190 years.

Tennessee cites a 1990 case between Georgia and South Carolina over islands in the Savannah River. The Supreme Court ruled the land belonged to South Carolina, which had taxed and policed the islands for decades.

Shafer and Carver, though, cite other high court rulings that dismiss "adverse possession" as the final say in border disputes.

"There is no room ... for the application of the principle that long acquiescence may establish a boundary otherwise uncertain," Justice Benjamin Cardozo wrote in 1934 upon resolution of a dispute between New Jersey and Delaware.

If Tennessee refuses to join the boundary commission, then Georgia will beseech the Supreme Court, Shafer said. South Carolina, for example, asked the high court last year to determine whether North Carolina is illegally diverting Catawba River water. The court appointed a judge to collect evidence, hear testimony and report back to the justices. The Supreme Court will hear arguments and issue a final opinion.

Shafer says Georgia is willing to make Tennessee a deal: Keep the 51 square miles in return for access to the river.

"We have a very strong claim to the entire disputed area," he said. "Either through negotiation or litigation the two states should agree on a borderline. [But] I would not be interested in a resolution of the border issue that denies Georgia its right to the Tennessee River."

Fed process lengthy

Georgia won't put all legal options in one basket. Shafer and Carver say easier access to the river may legally run through the federal government.

The TVA acquired land between the river and Georgia to build Nickajack Reservoir, which opened in 1967. A half-mile-long strip of land is all that separates the river from Dade County. The TVA's "marginal strip" policy allows adjoining property owners to "construct private water-use facilities upon approval of plans by TVA."

Carver said Dade's water authority could, for example, build a water intake facility and extend pipes to Nickajack Reservoir.

TVA spokesman Gil Francis says docks account for "99 percent" of the "marginal strip" permits along the Tennessee River. But commercial marinas, barge terminals, bridges and water intake facilities may also cross marginal strips, according to TVA guidelines.

Francis said a permit would entail a lengthy application process. And, like any withdrawal from the river, the TVA would have to approve an interbasin transfer — another lengthy process.

Twenty-five municipalities, utility districts or water and sewer companies have received TVA permits to take water from, or deliver water or sewage to, the Tennessee River, which runs from Knoxville atop Alabama and over to Kentucky.

North Georgia water systems hold four interbasin transfer permits, none for metro Atlanta. Tennessee state Sen. Andy Berke (D-Chattanooga) says Atlanta won't get a fifth.

"It would be unlikely that the TVA is going to let Georgia have an IBT (permit) of this water down to Atlanta," said Berke, who is shepherding the anti-boundary commission legislation through the Tennessee Senate. "We are looking to make sure our people have their water needs met. Atlanta is not the only area with water issues in this region."

The Tennessee River, though, is flush with water, according to a 2004 TVA study. By 2030, the Tennessee could supply Atlanta with 264 million gallons a day — triple the average amount used daily by the city of Atlanta last December — without "substantially" affecting river levels.

Berke said he won't make any water-for-boundary deal with Georgia.

"We're not interested in bargaining," he said. "Atlanta may have the Georgia Aquarium, but it will never have the Tennessee River."

Undercutting defense

Tennessee, though, may have no say in any dealings between Georgia and the TVA. The right of "adverse possession" — Tennessee's stated defense to date — doesn't apply to property not controlled by the state.

Tennessee, for example, provides police and fire protection to much of the disputed region. But the state doesn't provide those services on federal lands.

A border dispute between Maryland and Virginia may serve as a precursor this case. In 1996, Fairfax County, Va., sought permits for the construction of a water intake facility along the Potomac River. Maryland refused; Virginia sued.

Maryland asserted that it held centuries-old sovereignty over the river and, therefore, Virginia wasn't entitled to the water. In 2003, the Supreme Court sided with Virginia, deciding that "federal common law governs interstate bodies of water, insuring that the water is equitably apportioned between the states."