To get transit lines completed in the northern metro area, leaders will need to devise a clear vision and a convincing message.

Funding them is another large obstacle, and even with money, the process could take years from conception to opening, and along the way some crisis will likely arise.

Light rail experts from Phoenix and Charlotte provided metro area officials a sense of the uphill climb they face in getting transit, likely rail lines, in their counties.

Chamber, business and elected leaders from Gwinnett, Cobb and north Fulton convened at the Cobb Galleria on Wednesday to hear the advice, and to make the business case for high-capacity rail in the northern suburbs.

Light rail lines have been proposed in Cobb and Gwinnett counties to provide a regional transportation solution to alleviate traffic along some of the area’s most clogged corridors and provide economic development opportunities along the transit routes.

The transit lines -- if they make a final project list -- would be funded by a proposed regional transportation tax, which has the support of the chambers and community improvement districts, the self-taxing business groups that have invested heavily in transit studies along the corridors, as well as funding for voter education efforts with the transportation tax.

A wish list of $22.9 billion in regional transportation projects includes light rail lines -- from the Kennesaw area in Cobb to the Arts Center MARTA station, and from the Gwinnett Arena to the Doraville MARTA station -- as well as a project extending MARTA north to Roswell. The 10-county metro Atlanta region will vote next year on a pared-down transportation project list in a referendum, and on a 1 percent sales tax, which could collect $8 billion over 10 years.

“There are no easy answers for doing this and no one way to do this,” said Pat McCrory, former Charlotte mayor, who was instrumental in developing the city’s rail system. “It’s a process of many steps that has to be repeated several times during the process.”

That ongoing process includes everything from developing a succinct message -- which for McCrory and Charlotte’s system was, “I want to create the best of Mayberry and Metropolis" -- to communicating the plan to the community, securing funding, handling emergencies, and integrating the system into existing transportation plans.

“The greatest strength in this area is the regional approach, but is also your greatest challenge,” McCrory said, noting that all of the parties involved will have to give up some power and ego.

To help accomplish the goal, state lawmakers need to put money in transit, and the governor needs to develop a platform dealing with transit, said Norcross Mayor Bucky Johnson, who leads a roundtable executive committee that will initially pare the project list. "I think they should put their money where their mouth is."

Getting the projects’ support from a roomful of people with vested interests is much easier than convincing a divided public, including officials in other jurisdictions.

Political leaders in Fulton and DeKalb counties have been cold to a new transportation tax, while their jurisdictions — along with the city of Atlanta — are already paying a MARTA tax. Officials in other parts of the metro area have argued for some type of regional transportation governance body that takes MARTA under its umbrella with new leadership.

MARTA CEO Beverly Scott argued for a “level playing field” between any new projects and the existing MARTA system.

"Ultimately, the decision will come down to making the proposals relevant to taxpayers,” said Johns Creek Mayor Mike Bodker, who leads the Metro Atlanta Mayors Association.

“I’m not just thinking about [next year’s] July referendum, I’m thinking about the one that’s 10 years later, and the one that’s 10 years after that,” he said. “If you can tie this referendum in to solving [the usual, heavily clogged] congestion points, what’s the chance that people don’t say yes the second time and the third time?”

Staff writer Patrick Fox contributed to this article.