The Old Main Post Office straddling Congress Parkway has sat vacant since 1996. The city moved Tuesday to seize the hulking property via eminent domain. View Full Caption DNAinfo/David Matthews

CITY HALL — A city panel moved Tuesday to seize control of the Old Main Post Office spanning Congress Parkway and offer it to new developers, even as the current owner threatened "potential litigation" over the action.

Calling it "one of the city's most prominent riverfront redevelopment sites," Mary Bonome, deputy commissioner in the Department of Planning and Development, said "little or no action" had been undertaken at the building since a plan was approved in mid-2013, and "no significant work has been created to date."

When one member of the Community Development Commission asked why they were taking the action to seize it by eminent domain Tuesday, Bonome said it was "because of the lack of serious progress by the owner" and that "they have not displayed that they're serious about the redevelopment of this site."

Charles Hubbard, spokesman for the owner of the Old Main Post Office, said he was "surprised and very upset by the eminent-domain threat." View Full Caption DNAinfo/Ted Cox

She also said the owner, International Property Developers North America, had "struggled to maintain the current building in a safe condition."

Yet John George, an attorney for the owner, begged to differ, saying it was typical to set a six-year sunset on a development project. "We have done an enormous sum of work," he said. He called the seizure "unfair," adding, "I think we should be entitled to continue with our efforts."

Charles Hubbard, spokesman for lead owner Bill Davies, said he was "surprised and very upset by the eminent-domain threat" and that it was complicated arranging financing for such a massive project, especially in the wake of the Great Recession in the late 2000s.

"We can assure you we have been working non-stop on this project," Hubbard said. "The action you're taking has the potential to kill two and a half years' work."

Ald. Danny Solis (25th) defended the seizure.

"It is a building that is badly in need of rehabilitation," he said. "I believe the city needs to act on this immediately."

Ward Miller, executive director of Preservation Chicago, likewise supported the city taking control of what was once the world's largest post office.

"This is an amazing structure," he said, pointing out it was designed by the same architecture firm behind similarly massive structures like the Field Museum, the Adler Planetarium and the Merchandise Mart.

The commission basically took the two-part action to seize control of the site and put out a request for proposals (RFPs) on redeveloping it, with responses due June 10 and a new developer to be picked in July. Yet the city will not technically seize ownership, instead calling for an "eminent-domain fair market value" price to be paid as part of the RFP.

"It's interesting how the city can issue RFPs on property it does not own," George said.

His legal colleague Joseph Bisceglia threatened "potential litigation."

"This thing could be protracted," warned Commissioner Robert Buford, who cast the lone vote against the seizure. He was joined by Commissioners Leslie Davis and Cornelius Griggs in voting against the request for proposals, but that too passed.

Mayor Rahm Emanuel cheered the action, which he first proposed last month.

"Today the city of Chicago took a major step towards redeveloping the deteriorating Old Main Post Office and turning it into an economic engine that will bring thousands of jobs to the Near West Side and all of Chicago," Emanuel said in a statement. "This historic gateway to the city has sat vacant for two decades, and we cannot waste any time in moving forward with its development."

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