Crain’s New York Business: What is the Sunnyside Yard deck plan — and why has it not yet been built?

If the duo can actually pull off the project, it would represent far more than just the continuation of one of the most unlikely political partnerships in recent history. It would also mean they were able to see through a vision for a site the city has long viewed as a prime candidate for housing but has never been able to complete.

A plan already in place

The city will not be starting from scratch if it does move forward on the Sunnyside Yard plan.

In 2014, Amtrak wanted to reorganize some of its operations at the yard. The corporation consulted with the city to avoid making any changes that could preclude a future overbuild. This was on Amtrak officials’ minds because housing developments at the site had been pitched time and again since the 1960s. Many city planners had floated the idea of decking the yard to build new housing, and there was even a pitch at one point to build a domed stadium for the New York Jets atop the site.

Those 2014 conversations between Amtrak and city officials ultimately led to a study on the feasibility of decking the yard. In 2017, the Economic Development Corp. published the report, which concluded it to be “technically feasible, but complicated, to deck over Sunnyside Yard.”

Among the study’s key findings was that it would be too difficult to deck over the main line, which covers about 15% to 20% of the site, because of near-constant rail activity that could not reasonably be suspended for extended periods, making construction difficult. Any future planning for the site would have to account for that limitation.

Still, the Economic Development Corp. under former Mayor Bill de Blasio showed it would be possible to build a deck over the majority of the tracks for a sprawling mixed-use project.

The city issued a request for proposals for the site and in 2018 selected a team led by famed architect Vishaan Chakrabarti’s firm, PAU, to develop a master plan. That became the proposal pitched in March 2020.

The $14.4 billion vision called for building 12,000 affordable homes atop the rail yard over several decades in what the city and Amtrak described as the largest planned affordable housing community for the five boroughs since Co-op City in the mid-20th century. The residences would have been split between 6,000 rentals and 6,000 homeownership opportunities. The plan also included 60 acres of open space, multiple new schools and a new rail station for the neighborhood.

The document’s language stressed that it did not represent any final decisions for Sunnyside Yard, and the project never came to fruition, in part because the pandemic effectively froze it in its tracks. When Eric Adams took office about two years later, he showed little appetite for taking on the ambitious project.

Development at Sunnyside Yard did not return to front-page headlines until six years later, when Mamdani printed his own.