Conservation Commission members, expressing satisfaction on how work would proceed on the largest downtown development in decades, in Wednesday unanimously approved the application for the Bedford Square complex proposed for the site of the Westport Weston Family Y.

The Planning and Zoning Commission will be the next stop for the applicants, who have proposed a mixed-use development at the Y property at 59 Post Road East and the adjacent 35 Church Lane. The developers hope is to begin construction by fall of 2014, when the Y plans to move to its new home on the Mahackeno property.

"We thought it was a helpful, productive process," said Karen Johnson, vice president of development for Charter Realty & Development Corp., part of Bedford Square Associates, LLC. "Conservation Commission members are very dedicated to their charge, and we believe the result is a better plan for Bedford Square and for Westport."

The commission had conducted three previous hearings on the plan, which includes renovation of the downtown Family Y building and new construction into a 60,000-square-foot development that would house retail, residential, restaurant and office space, as well as a 100-space underground parking garage.

Along with the 14 standard conditions for approval of a development application, the commission added six other special conditions that must be followed for the Bedford Square project.

These stipulations include conformance to plans that were previously reviewed by the commission, a deed restriction "to acknowledge that the operation and maintenance of active floodproofing measures ... is the obligation of the owner," and that a site monitor should be on-site as needed to assure that "discharge water leaving the site is properly filtered and excess sediment does not discharge from the site to adjacent waterways."

The other special conditions include that the fnal approved plans be submitted through the town's Engineering Department for both construction and stormwater maintenance, as well as any changes in design or engineering "that affect the footprint or basement elevation and floodproofing ... require additional review and approval."

These stipulations were arrived at through individual input from some commissioners, who submitted their comments and concerns to Alicia Mozian, conservation director.

"Ralph wanted to make sure that site monitoring was taking place during all the possibilities when de-watering may have to take place," Mozian said, referring to Commissioner Ralph Field. "That, we anticipate, will definitely be during excavation, but you never know if they may need it during construction."

Johnson said the application has not yet been submitted to the Planning and Zoning Commission, but it will likely be done within a month or so.