What would it take to dredge and construct an entirely new sixth borough in the middle of New York Harbor? It's an interesting question that preoccupies writer Jon Methven over at The Awl.

Methven recounts the history of land reclamation in the city—from the dredging of Battery Park City and Liberty Island, to the bizarre proposals to fill in both the East and Hudson Rivers.

Once such plan was "LoLo"—or, "Lower Lower Manhattan"—a 2011 proposal put forward by Columbia University's Center for Urban Real Estate to connect Governors Island to Lower Manhattan and Red Hook via dredged land bridge. The plan, argues researcher Scott Hayner, was economically and physically feasible, and would have been less expensive than building a tunnel between Brooklyn and Manhattan. The reclaimed land would also provide much needed housing and other infrastructure.

"Affordable housing, no matter who you talk to, is one of the things the city is lacking," Hayner tells The Awl. "You can provide developers the opportunity to build affordable housing, at a price that makes sense because you're able to dictate the amount of land and development rights to be used for office and residential use."

However, Ted Steinberg—a professor at Case Western University specializing in New York City's ecological history—argues that such drastic dredging plans do not take into account longterm flooding models, which could be devastating within 25 years. He also brings up other issues, citing the need for a "moral impetus" behind such a project.

"If you came to me and had this idea for a sixth borough that was going to solve our homeless problem, I might think of ways to proceed," he says. "But this is creating millions of square feet of space to make developers money. It's not solving the homeless problem, or any problems."

Methven spends much time discussing the nitty gritty details of building a sixth borough (an engineer who worked on the Liberty Island dredging project estimates a cost of around $300 million). He and his interview subjects admit that a feat that would so fundamentally change the coastal landscape of New York is unlikely to happen in our lifetime, but it's a fascinating and timely read nonetheless.

· Let's Build a Borough [The Awl]

· All LoLo coverage [Curbed]

· Thought Experiments archives [Curbed]