A development group wants to tear down a massive concrete barrier between City Hall and the West End and North End neighborhoods.
HYM Investment Group submitted a project notification form Wednesday to the Boston Redevelopment Authority concerning the 2,300-space Government Center Garage.
The garage, which spans over Congress Street and is located between New Chardon and New Sudbury streets, would be replaced by multiple buildings including two that would be 45 and 48 stories.
The total project consists of six buildings, the highest being 600 feet. More than 700 housing units, a mix of condos and apartments, 200 hotel rooms, office and retail space would be the make up of the buildings.
A portion of the current garage, which is located at the Haymarket MBTA station, would be torn down. About 1,100 spaces would remain. The Haymarket bus station would be reconfigured.
The project calls for a new plaza to reconnect the Rose Kennedy Greenway and the Bulfinch Triangle, the area around Portland and Canal streets. Plans include an 850-space bicycle parking and storage facility for residents and employees with showers and changing rooms and 32,000 square feet of green roof and roof garden/deck space.
Construction wouldn't begin until 2016 and will take many years because of the size of the project. The dates are flexible, the development group said.
"By replacing a massive unsightly barrier with two new vibrant mixed-used and appropriately scaled urban blocks, the project will substantially contribute to improving the vitality and the urban design and architectural character of the Government Center and Bulfinch Triangle areas," wrote Thomas O'Brien, HYM's managing director.
The project seems to have the backing of Mayor Thomas Menino.
"Depressing the Central Artery gave rise to the Greenway and strengthened the connection between downtown and the waterfront," Menino said in a statement. "I'm pleased that the redevelopment of the Government Center Garage looks to extend those connections – further linking our growing neighborhoods."
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