Any hope developer Don Chiofaro may have had of building a larger project on the city's waterfront appeared to end Wednesday when Boston officials said they would not budge from size limits they imposed on his Harbor Garage site last summer.
Rich McGuinness, a waterfront planner for the Boston Redevelopment Authority, said the city will not allow Chiofaro to build more than 900,000 square feet of space — or buildings taller than 600 feet.
While that would still allow for one of the largest developments in Boston's current building boom, it is far short of what Chiofaro had sought. The two sides had been negotiating in recent months since the city first proposed the size limits for the property, including a meeting between Mayor Martin J. Walsh and executives from Prudential Real Estate Investors, Chiofaro's financial backers and majority owner of the property on Atlantic Avenue.
The developer has indicated he needs the more sizable project to cover the complex undertaking of building near the waterfront, including closing a profitable parking operation and replacing its 1,400 spaces underground. He's previously floated a proposal for a two-tower complex of office space, housing and retail at 1.3 million square feet.
Chiofaro has said little publicly about the impasse with the city. But in a statement released after a public meeting over new zoning rules for the downtown waterfront, the often-blunt developer sounded a conciliatory note.
"We haven't made any decisions as to what's next," Chiofaro said. "We will continue participating in the process, see it through to conclusion and review our options moving forward."
In the meantime, Chiofaro added, "we have a healthy, high-performing asset in the existing garage, which allows us the opportunity to be patient."
In their meeting with Walsh, Prudential executives had apparently offered a compromise of sorts, McGuinness said, indicating that a project of 1.1 million square feet would be economically feasible.
However, McGuinness said Massachusetts environmental officials, who must approve any zoning plans involving the waterfront, had already ruled out a larger project for that area.
The state "made it clear to us they would not consider any recommendations beyond what we'd outlined in June," McGuinness said. "Not above 900,000 square feet, and certainly not above 600 feet tall."
The city continues to come under criticism from neighbors, including the New England Aquarium, who say that a 900,000-square-foot complex is still much too large for such a congested spot on the waterfront.
"I don't really understand why we're stuck with 900,000," said Diane Rubin, a resident of neighboring Harbor Towers, where many residents have argued against such a big project. "There are a lot of concerns that have been raised about that level of density and I don't think it has been justified."
Meanwhile, McGuinness said the BRA will push ahead with a broader harbor zoning plan that has been stalled for months while the city negotiated with Chiofaro, with an eye to finishing it by summer.
Nigella Hillgarth, chief executive of the New England Aquarium, said the city needs a more thoughtful analysis of the entire downtown waterfront, rather a planning process that was driven by a single project.
"A lot more thought needs to go in to what the whole harborfront needs," she said.
That's partly why McGuinness says it's time to push the process forward. Chiofaro's garage is but one property in a stretch of the waterfront from Long Wharf to the Northern Avenue Bridge that the city is considering rezoning. At least two other large, though less contentious, developments are being proposed in that strip.
Discussion at the study's citizens advisory committee will now shift to what sort of public benefits would be required of any developments that add density or create wind or shade problems for the area. McGuinness said he hopes to wrap up a plan by summer and send it to the state for approval.
Even that notion, though, quickly drew concerns from neighbors wary of Chiofaro.
At Wednesday's meeting, McGuinness said the BRA would hire veteran development consultant Pamela McKinney to help craft those public-benefit requirements. Not long after it was over, opponents noted that, several years ago, McKinney worked for Chiofaro as an adviser on the garage project.
"That's a little unusual," said Aquarium spokesman Tony LaCasse. "We definitely noticed."
Less than two hours later — after receiving questions from the Globe on McKinney's role — the BRA said it would hire someone else for the work.