From suburban road widenings to urban interchanges to new MARTA lines, $6.1 billion worth of metro Atlanta transportation projects survived final challenges Tuesday, and stand ready to be approved this week as the 10-county region’s proposed project list.

If approved by regional officials in a vote scheduled for Thursday, the list will go before voters next year in a referendum, along with a regional 1 percent sales tax over 10 years to fund it.

“I’m relieved,” said B.J. Mathis, chairwoman of the Henry County Commission.

Mathis is among the 21 mayors and county commissioners from across the region who are on the “roundtable” forming the project list. Many were not certain that representatives of such disparate areas as the urban, suburban and rural parts of the region would be able to agree on splitting up so much money in a time when transportation funds are so rare and sought after.

Mathis raised one of the final challenges to the list, a concern that Georgia Regional Transportation Authority Xpress commuter buses needed more funding. Outer counties including hers argued that the money should come from inner counties’ projects, such as funding for MARTA repairs.

The final struggle was a remarkable change from years past, in that the outer counties were fighting not for a road project, but for a transit system -- just their own preferred transit system.

The Xpress bus issue was proposed for discussion last week but raised tensions so high that members put it off and scheduled a special meeting Tuesday to deal with it and other remaining loose ends.

“The parties are trying to work out an amendment that risks tearing apart this entire process,” Atlanta Mayor Kasim Reed said last week, advocating to give them time.

After last week's meeting, staff and elected officials from several counties met and worked out a solution. Of the $180 million that GRTA staff say they need to keep running at full tilt for 10 years, some work will be taken over by other referendum projects that include commuter bus service.

It's a silver lining for the limits of the mass transit plan in the list.

Advocates originally proposed rail lines for mass transit projects in the corridors of eastern I-20, I-75 in Cobb County, and I-85 in Gwinnett County, but there wasn't enough money or support to do them all.  However, each of those transit corridors received partial funding, which will deliver studies and possibly form the foundation for future rail line construction. In the meantime, there will be commuter bus service there, which takes the edge off the shortfall for Xpress commuter buses.

That still leaves GRTA short $33 million, but the roundtable passed a resolution pledging to work to fund the gap from existing transportation revenue.

Mathis had fought for the bus service.

"We cannot afford to lose service in Henry County," Mathis said last week, saying the roads were bad enough without pouring all those bus commuters back into their individual cars. "Every lane in Henry County will be failing at that point."

Nothing is certain about the list until the roundtable takes its final vote Thursday. The draft list that the officials have been working with since Aug. 15 was drawn up by only a handful of them, not the full group. But there has been little grandstanding, and each of the proposed changes to the list has passed the 21-member group by a solid margin or unanimously.