Amtrak and its partners in the proposed redevelopment of a massive swath around 30th Street Station in University City say the decades-long plan - including partially capping the adjacent rail yard - will involve $6.5 billion in infrastructure funding and private investment.

The financial projection is part of the planning team's final blueprint for the 175-acre site extending northeast from 30th Street Station, to be released Thursday morning.

Publication of the 30th Street Station District Plan ends a two-year, $5.25 million study led by Amtrak, Drexel University, Brandywine Realty Trust, SEPTA, and PennDot for the area between Walnut and Spring Garden Streets east of Drexel's campus and Powelton Village.

Concrete steps can now be taken to realize the plan, said Rina Cutler, Amtrak's senior director for major station planning.

"We all ultimately knew that we wanted to create a process where the object of planning was action," Cutler said in an interview ahead of the release.

The 35-year plan to build a dense urban neighborhood, largely over what are now 88 acres of rail yards, will require about $2 billion in infrastructure investment, according to a plan summary. That spending on roads, bridges, parks, and transit would enable about $4.5 billion in private investment by developers of office towers, residential buildings, hotels, and other projects.

Anticipated is about 18 million square feet of new development, the equivalent of nearly 15 new Comcast Towers, including enough housing to accommodate up to 10,000 residents. The commercial space includes about 1.2 million square feet planners hope will be occupied by a single corporate, commercial, or institutional tenant that will anchor the development, though none has yet been secured.

Brandywine Realty Trust expects to bid for this work alongside developers that have not been involved in the planning so far, said Jeffrey Weinstein, the company's vice president for construction.

The station district plan's earliest steps include a decision by SEPTA on the precise placement of an underground concourse linking its subways and trolleys with a 1930s station building, Cutler said.

Amtrak, meanwhile, will soon begin taking steps with PennDot to allow relocation of a Schuylkill Expressway ramp to accommodate an intercity bus terminal north of the station, she said. The rail corporation is preparing to start planning the landscaped, pedestrian-friendly plaza that will surround the station.

Another element of the station district plan slated for completion over the next decade involves improvements to the station's interior, with upgraded retail and a new passenger concourse.

"Where we are now is this great inflection point," said Keith Orris, Drexel's senior vice president for economic development.

Later parts of the plan involve the staged capping of the rail yards, where 10 million square feet of the new development is anticipated, as well as a skyscraper beside the planned bus station.

Another tower is planned on an Amtrak-owned parcel behind 30th Street Station, where Brandywine once discussed building an office project called Cira Two.

Brandywine's nearby projects include the Cira Centre office building north of the station and the 49-story FMC Tower being completed to the south. The Radnor-based developer also is a partner with Drexel on the $3.5 billion Schuylkill Yards redevelopment project on a cluster of mostly university-owned properties southwest of the planned station district.

The former Cira Two parcel now sits at the intersection of the two large redevelopment proposals, Cutler said.

"The market will ultimately dictate what goes there, but we think it's a very valuable development site," she said. "It really is the linchpin of the entire district."

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