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The city is seeking a master developer to kick off the planned conversion of the former St. Elizabeths mental hospital near Congress Heights into a mixed-use community with housing, offices, shops, and a tech center.

The mayor’s office released a request for proposals today for a developer to spearhead the first phase of the redevelopment project. That phase will include about 200 housing units, 600,000 square feet of office space, and a 175,000-square-foot technology “innovation hub,” as well as management of the site’s interim spaces.

Today’s request is the biggest solicitation in the long, stuttering process to find developers for the St. Elizabeths East Campus. In November 2012, the city issued a request for developers to rebuild four parcels at the campus’s southern edge, then rescinded that request in favor of starting with a search for an academic anchor—-a search that has yet to conclude.

The St. Elizabeths development has the potential to transform Congress Heights, one of the city’s poorest neighborhoods. Across the street, the Coast Guard has moved into the federally owned St. Elizabeths West Campus, and the Department of Homeland Security is expected to join it, although it’s unclear to what extent these federal employees will actually interact with the neighborhood. Mayor Vince Gray reshaped the development of the East Campus last week with the announcement that the city will pursue the construction of a new hospital there.

The first phase consists of five parcels (see map above). Closest to the Congress Heights Metro is the “Congress Heights Center,” expected to be an office complex. Some of the existing buildings there will be demolished; others could be demolished or retained. Just to the west will be the “CT Village,” named after the former continuing treatment section of the hospital. The residential development there will make use of seven two-story historic buildings with enclosed porches and red tile roofs. Units will range from 450 to 1,450 square feet. The rooms will feature high ceilings; the distance between the first and second floors is nearly 12 feet. A portion of the units will need to be set aside for low-income residents under the city’s inclusionary zoning law.

Finally, the two northwest parcels, farthest from the Metro, will become the innovation hub. This portion consists of two existing buildings and the opportunity to construct a new one that the solicitation states would be “ideal for office, classroom, research, and production assembly.” Microsoft is thought to be the leading contender to anchor the tech hub.

The developer would also be required to take over the interim spaces on the site, including the Gateway Pavilion that hosts food sellers and other retail functions.

The city is seeking bids from interested developers to buy the land or enter into a ground lease. Developers must submit their responses by June 27. The city hopes to select a master developer in November.

Map from the RFP