The city originally asked for $20 million for the 810-space garage, but the highest bidder - Chicago-based InterPark LLC - eclipsed that figure, offering $29.6 million.
Clarke and Nutter looked triumphant announcing their agreement during a news conference in front of Robert Indiana's iconic "LOVE" sculpture yesterday afternoon.
"The refurbishment of this park is long overdue," Clarke said.
"This was not an adversarial relationship, although it may have appeared to be that way in some of the press accounts, but the reality is that we have been working together over the last several months. I'm excited about the prospects of having a well-balanced approach to redoing this park."
Last month, Clarke entertained a proposal for seven restaurants on the park apron - the revenues of which he envisioned would pay for the renovations. But backlash from community groups may have struck a chord.
"This is good news, but it remains to be seen what the details are," said Lauren Bornfriend, executive director of the Philadelphia Parks Alliance, who represents one of the more vocal objectors to the restaurants proposal.
"Our assumption is that, with the public process, the plan they arrive at will look very different. We'll continue to be vigilant to ensure city and state laws that protect parkland are adhered to."
Nutter said he wants to see food or restaurant concessions balanced with enhanced green space for the park. He said the city would apply for $3 million from the commonwealth's Redevelopment Assistance Capital Program.
"Remaining costs would be funded either through proceeds from the sale of the garage beneath the plaza, through the city's capital investment program or both," said Nutter, who invited private corporations and foundations to share input.
"We welcome institutions to step forward immediately if they are interested in this project," he said.
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