ATLANTA — After an expected nod from the Senate, Gov. Sonny Perdue will be officially authorized to begin border dispute negotiations with Tennessee Gov. Phil Bredesen — and told to file suit if talks fail.

In a move meant to capture part of the Tennessee River and help slake Atlanta’s thirst, the Georgia House passed Sen. David Shafer’s amended legislation claiming the Tennessee-Georgia border is 1.1 miles too far south.

The Duluth Republican’s bill, which has gotten more attention than most legislation this session, was amended to drop its call for border commissions from both states to negotiate after Tennessee lawmakers refused to participate.

“It reasserts our rightful claim to the border with Tennessee and to the water of our shared Tennessee River,” Sen. Shafer said about his resolution, which seeks to “correctly mark” the state’s northern border at the 35th parallel.

Survey crews using primitive tools in 1818 plotted the state line more than a mile north of the 35th, which was the state line approved by Congress when Tennessee was established as a state.

Georgia has occasionally raised objections to the mismarked boundary over the nearly 190 years since the line came into question.

The objections took on new vigor this session, with parched Georgia eyeing the ample Tennessee River.

The House passed the amended resolution 132-24 Friday, and the Senate was expected to give its procedural vote of agreement.

Some lawmakers resisted the water-grab tactic.

Rep. Brian Thomas, D-Lilburn, said fellow legislators were “looking at the Tennessee River as a canteen for the metro Atlanta area” instead of acting on bills to set conservation measures, update plumbing or repair water lines.

Many of those bills were never even heard in committee.

“We seem unwilling to respond in constructive ways,” Rep. Thomas said. “With this, we find ourselves grasping at straws from which we hope to suck water from the Tennessee River.”

Northwest Georgia legislators voted in favor, though, including Rep. Ron Forster, R-Ringgold, who was among 26 earlier “no” votes.

He said he now thinks Tennessee should be open to water-sharing talks, but is wary of the border shift.

“I don’t agree with putting all the people that are in this area in such a situation over a water dispute,” Rep. Forster said.

Gov. Perdue’s office said he will accept the negotiating duty.

While Gov. Bredesen’s office reiterated this week the governor has no interest in giving up land or water, Sen. Shafer will not give up.

“I remain hopeful that our good friends in Tennessee will work with us in a neighborly fashion,” he said.