The battle between residents and a developer over plans for a big-box store in Grant Park intensified Thursday as backers of the project slapped Atlanta officials with lawsuits over a recent zoning change.

Fuqua Development and Lafarge Building Materials, which owns the 20-acre property that Fuqua is set to convert into a large retail center, claim the city’s Sept. 3 decision to rezone their parcel on Glenwood Avenue from industrial to residential has harmed the project.

While it doesn’t stop the developer from obtaining building permits, attorneys for both companies say the rezoning diminished land value, stalled their project and makes getting the necessary financing more difficult.

“We don’t have any choice but to fight, because we’re fighting over millions of dollars here,” said Doug Dillard, an attorney with Weissman, Nowack, Curry and Wilco, which represents Lafarge.

The Atlanta City Council granted District 1 Councilwoman Carla Smith’s request to rezone the land after months of lobbying by residents unhappy with the proposed project called Glenwood Place. The development calls for a 144,000-square-foot anchor tenant, rumored to be a Wal-Mart, to sit alongside a future stretch of the Atlanta Beltline.

Residents say the proposed strip mall is in conflict with the master plan and vision of the Beltline, a transit project they’ve long hoped would help revitalize their historic communities. The development will be located at Glenwood Avenue and Bill Kennedy Way off I-20 and will sit across from Maynard Holbrook Jackson High School and Glenwood Park.

Atlanta Mayor Kasim Reed’s office does not comment on pending litigation, and Smith, who represents the Grant Park area, declined comment on the lawsuits but had a simple explanation for proposing the rezoning: “The community asked me to do it.”

Here’s where it gets complicated: To a large degree, the city and Fuqua are in agreement that the developer can continue seeking necessary permits because the project was approved under the previous industrial zoning. In July, the city’s planning department granted Fuqua a “special administrative permit,” a key step in acquiring the final building permit.

However, attorneys for Fuqua and Lafarge say the rezoning has effectively clipped their wings for several reasons. They claim the city delayed the project and that the rezoning decision is “arbitrary and capricious.” They take issue with the Beltline overlay, a series of design requirements pertaining to streets, sidewalks and lighting, and say the required elements consume 25 percent of the site. That, they believe, amounts to an unconstitutional taking of their land.

Finally, they assert the rezoning impedes their ability to secure required financing. It’s common for properties in an area that is rezoned to be “grandfathered” in and given a nonconforming status. But, in this case, Fuqua’s development isn’t yet built.

“The problem is, who is going to lend money for something that will be nonconforming to its zoning before it’s even built?” said Sharon Gay, a McKenna Long & Aldridge attorney, who, with James Washburn, is representing Fuqua. “And who is going to insure it?”

The companies are seeking an injunction to reverse the zoning decision, Gay said.

Attorneys for Lafarge assert that the rezoning has diminished the property’s value by limiting the possibilities of development. Should a deal fall through with Fuqua, Lafarge would only be able to sell its land to someone who plans to build apartments on the lot, which has been home to a concrete plant and other industrial uses for years.

They say it’s unlikely they would find a buyer willing to pay the same as Fuqua. (Neither side has disclosed the amount of their deal.)

For residents of the area impacted by the proposal, the lawsuits are another chapter in a monthslong saga. The issue has united people from across the area, including Ormewood Park, Cabbagetown and East Atlanta, who stand behind a simple slogan: “Save our Beltline.”

“We’ve gotten so far, and it’s a nail biter every step of the way,” said Lauren Rocereta, president of the Grant Park Neighborhood Association.

They will be taking their fight back to City Hall Thursday. The Board of Zoning Adjustment is expected to consider their appeal of the city’s decision to grant Fuqua the special administrative permit on the grounds it’s not in line with the Beltline master plan regulations. City planners said last month that plan is merely a suggested vision — not the final word.

Rocereta said residents would prefer a mixed-use, multi-level project instead of a sprawling big-box store. And they dislike the site design, which features a spread of asphalt between stores.

“Welcome to Grant Park-ing lot,” Rocereta said.

Jeff Fuqua, who has built dozens of retail and residential projects across Atlanta over the past few decades, said this is the first time his company has sued the city.

“This is really weird,” he said of the circumstances leading to the lawsuit. “And we’ve done a lot of controversial things in people’s minds, too.”

Jonathan Hawkins, a partner with Krevolin Horst who specializes in property disputes but is not involved in this case, said he expects the lawsuits to take months or longer to resolve because of the complicated factors. But it is not surprising that the issue has found itself in court, he said.

“Sometimes the developer wins and sometimes they don’t,” he said. “(Fuqua) wins a lot of them.”