The question of what to do with Portland’s Congress Square is officially headed back to an advisory group that spent several years evaluating how to improve the public space.

Portland City Council members voted Monday night to request that the Congress Square Redesign Study Group evaluate two options for Congress Square Plaza: redesigning the plaza while maintaining its current footprint, or redesigning the plaza while developing two-thirds of the space with an event center featuring a rooftop park.

The group, which first met in 2010, was also directed to recommend ways to improve the Congress Square intersection, where High, Congress and Free streets converge. The committee will complete its work by Nov. 17, thereby allowing the current City Council to consider any recommendations before new councilors elected in November take their seats.

The council also added two new members to what had been a 15-person committee. The new members are City Councilor Jon Hinck and a representative from the group Friends of Congress Square Park, which fought the city’s attempts to sell part of the plaza to Rockbridge Capital for a multi-purpose event center adjacent to the renovated Westin Portland Harborview Hotel.

The decision to revive the Congress Square Redesign Study Group came nearly two months after voters approved a referendum – organized by Friends of Congress Square Park and Protect Portland Parks – that blocked the sale by raising the threshold for the city to sell 60 public parks and other city-owned lands. Last month, the City Council failed to reach consensus on how to proceed in the wake of the June referendum.

While leaders of Protect Portland Parks cheered the two new members, they criticized the Nov. 17 deadline as too short and suggested that city officials were still attempting to influence the outcome by requiring the group to evaluate the option of an event center with a rooftop park.

“The members of (the study group) are highly capable and don’t need designs being forced on them yet again,” Protect Portland Parks board member David LaCasse said in a statement. “That’s what prompted a divisive referendum in the first place. The Mayor (Michael Brennan) and the Westin lost that fight and the citizens don’t need to revisit this issue.”

A handful of local residents also urged the council Monday night to broaden the study group’s charge beyond the two options. But several councilors said they believe the group already has the ability to consider other design options and supported the Nov. 17 deadline.

“I think it is important that this council has the opportunity to take action on this matter,” said Councilor Nicholas Mavodones Jr. “If [the report] is not ready for prime time, then that is the way it has to be.”

The redesign study group is expected to meet Aug. 20.