In a city where the length of public meetings often bears no relationship to the small size of the population, Mandeville’s marathon gatherings to discuss a proposed lakefront development are setting new records.

The owners of Port Marigny, a planned 78-acre mixed commercial and residential development just east of the Lake Pontchartrain Causeway, presented their conceptual plan to the city during the summer.

City officials, knowing that Mandeville’s fiercely engaged residents would want to pore over the plans carefully, scheduled four special two-hour public meetings of the Planning and Zoning Commission, which will make a recommendation on the plans to the City Council.

At this point, eight meetings have been held, with at least one more planned for December, and some officials are saying it’s time for the process to move forward. But the same issues that were raised at the beginning have yet to be resolved: the density of the proposed development and the impact of the new traffic it would generate.

No one says the site shouldn’t be developed. The 78 acres on which Port Marigny would be built form the long-dormant site of the old Pre-Stressed Concrete Products plant, a brown blot on Mandeville’s picturesque lakefront.

The owners, Michael and Marcus Pittman, announced last year they were planning to develop the site, and they held a series of informal meetings in the spring to discuss possibilities.

Almost immediately, residents raised concerns about the impact of a big new development on the surrounding neighborhoods, specifically asking how many residential units were planned and how many cars would be dumped onto surrounding streets.

Those concerns were not allayed in the summer, when the Pittmans presented their plans for the site, which included a hotel, restaurants, a marina, commercial areas and 429 residential units.

From the start of the Planning and Zoning Commission meetings, residents and members of the City Council questioned whether the area could handle what some estimated would be nearly 1,000 additional cars.

The Pittmans produced a traffic study; the city hired a consultant to critique it.

Eight two-hour meetings later, those issues remain unresolved.

“We need to bring that density down,” said Councilwoman Carla Buchholz, whose district includes Port Marigny. “Those concerns have not gone away.”

Buchholz’s wariness is shared by some of her colleagues on the council who must approve the conceptual plan before the project can go forward.

“This is scary,” Councilman Ernest Burguières wrote in an email to constituents last week. Burguières, whose district is just east of the site, has been aggressive in demanding more information about potential impacts on surrounding streets.

“The more I got into it, the more I learned about the traffic, it raised more questions,” he said.

Specifically, Burguières criticized the “internal capture rate,” or percentage of cars that would seldom leave the development, used by the Port Marigny owners.

“They are saying that because it’s a ‘new urbanist’ project, that will encourage people not to leave,” he said. New urbanist developments frequently combine residential and commercial areas in a compact, walkable environment. Port Marigny’s traffic engineer pegged the percentage of cars that would remain in the district most of the time at 30 percent, but Burguières and others have questioned whether that’s too high and suggested it should be as low as 5 percent.

Other questions remain. For instance, if the City Council approves the conceptual plan, does it effectively approve 429 residential units for the project? Or could that number be reduced during further negotiations with the city during the permitting process?

“That’s the controversy,” Buchholz said.

City Planning Director Louisette Scott said that approving the conceptual plan would set 429 units as the maximum, but that number could move downward during the development and permitting process.

Richard Muller, who represents the Pittmans in their dealings with the city, said Port Marigny’s plans are well within city zoning regulations.

“No waiver or variances are being requested” for density, he said.

Muller said the Pittmans are frustrated by the slow pace of the review of their plans, but that they remain willing to work with the city.

On that, at least, there is some agreement. Buchholz said she appreciated that the meetings have allowed for transparency and accountability, but it is time to move forward. In other words, the Planning and Zoning Commission needs to make a recommendation soon and let the City Council have a crack at it.

But when that will happen is still up in the air. The next commission meeting is tentatively scheduled for Dec. 17, after the City Council’s lone December meeting. That means the council could not get the commission’s recommendation until January. And with a city election set for March 5, Port Marigny could become a political issue, perhaps delaying action even further.

The series of meetings “has been long and arduous and not very user-friendly,” Buchholz said.

Muller agreed.

The Pittmans “would like to see something done and get it built,” he said.

Follow Faimon A. Roberts III on Twitter, @faimon.