Aldermen last night moved forward in what will be a long process toward a potential mixed-use development at the Austin Street municipal parking lot.

In a meeting of the Real Property & Reuse Subcommittee, aldermen voted 5-1 in favor of declaring the Austin Street lot as surplus for sale or lease.

Within the vote, Aldermen clarified that the city retain no less than 85 parking spaces in the lot. Currently, the lot fits 159 spaces.

"This is where the real work begins," said Candace Havens, director of the Planning & Development Department.

Both Public Works Commissioner Thomas Daly and Havens had to recommend the property as surplus prior to the subcommittee's vote.

Once the committee voted the property as surplus, it then unanimously decided to form a joint advisory planning group, which will study the area and potential projects, eventually making a recommendation to the subcommittee.

As several aldermen noted during both the subcommittee meeting and subsequent full board meeting, a project at the Austin Street lot has been in the works since 2005 and has involved several community meetings as well as a study done by interns at the Watertown-based planning and design firm, Sasaki Associates.

"This is an extremely complicated project that the Planning Department and citizens have been involved with for a long time," said Alderman Deborah Crossley.

As outlined by Havens and the Planning Department, the process that would result in a project at the lot involves many steps, including studies, public hearings, subcommittee and full board approval of any possible recommendations.

The city will also have to re-zone the area to a Business 4 district.

The 1.7-acre site has close proximity to both MBTA buses and a Commuter Rail station, making it a convenient location for a mixed-used project, which would include both residential and commercial property.

However, Alderman Leonard Gentile showed reservations with the potential loss of parking spaces if a project were to develop on the site. Gentile, a member of the Real Property & Reuse Committee, was the sole opposition to last night's subcommittee vote.

Real Property & Reuse Chairman Vicki Danberg reported the subcommittee's vote and discussion to the full Board of Aldermen, which met immediately afterward.

"I'm not really comfortable with the potential loss of 74 parking spaces," Gentile said to the full Board of Aldermen last night.  "That seems like an awful lot to me."

The 85 spaces the city says it wants to retain, Havens explained, is based on an estimate of what the city believes is the average demand for the lot.

There is a chance that parking could be added back into a project, Havens noted, and that the 85 spots is a "baseline minumum."

Alderman Allan Ciccone also expressed concern to the full board about lack of parking in an area of the city that has recently tried to revitalize its village center and business district.

Gentile felt the lot's abutting residents do not likely know there is talk of a project developing on the lot, which, if over 20,000 square feet, will need a special permit, Gentile said.

Alderman Stephen Linsky tried to reassure Gentile, though, explaining that this will "totally be a public process" complete with a public hearing on whatever recommendation the advisory group forms.

Moving forward that joint advisory planning group, "is an important step," Gentile said.

"I'm not trying to stop progress," Gentile added. "I just wish I had more information."

During the a full board discussion, Crossley reiterated her support for the steps the city has taken to control a potential project on the site.

"I'm very enthusiastic about the process," Crossley said. "I think it's the first time in a long time that Newton is taking the reins of a development and telling the developer what it wants in advance."

Among the potential for economic development and housing, Alderman Marcia Johnson said a possible project on the Austin lot could bring Newtonville a real "sense of place."

"We're trying to create a new vision for Newtonville," Johnson said.