Earlier this month, the first phase of Hudson Yards, a $25 billion neighborhood suspended atop an active rail depot on the western fringes of Midtown Manhattan, opened to the public. It was met with withering criticism for its perceived lack of street-level spontaneity, its failure to be a welcoming place for all New Yorkers and for the "shawarma-shaped stairway to nowhere" in the middle of it all.

All of the castigatory hubbub around Hudson Yards has meant that another proposed Manhattan megaproject with an estimated $10 billion price tag that also could forever alter the landscape of New York City has been somewhat overlooked.

And this is a shame given that this particular project, unveiled by New York City Mayor Bill de Blasio the day before Hudson Yards' opening, doesn't involve multi-million dollar luxury apartments, contentious climbable sculptures or high-end shopping malls. And, God willing, it never will.

Focused on resiliency, it's an equally as massive an undertaking than Hudson Yards, if not more. Its main function is to fortify swaths of Lower Manhattan against rising seas by extending the island's southeastern shoreline by as much as 500 feet — roughly equivalent to two short city blocks — into the East River.

Manhattan's Financial District as viewed from South Street Seapot Room to grow? Expanding the Financial District further into the East River via land reclamation may be the only way to save it from fast-rising seas. (Photo: Spencer Platt/Getty Images)

Protecting Lower Manhattan by building out

In the years immediately following Hurricane Sandy, ambitious plans to shield Lower Manhattan from climate change-fueled coastal inundation were hatched, starting in earnest in 2014 with The BIG U. The winning proposal of the U.S. Department of Housing and Urban Development's Rebuild by Design competition, The BIG U was conceived by an interdisciplinary team headed by Bjarke Ingels Group to act as 10-mile-long "protective ribbon" that would wrap around Manhattan's most flood-prone neighborhoods like a snug, waterproof glove.

Featuring plant-topped berms, public parkland, artist-decorated flood walls and other elements to help stave off catastrophic flooding, the proposal was designed to "not only shield the city against floods and stormwater" but to "provide social and environmental benefits to the community, and an improved public realm."

The BIG U has since been broken down into individual, neighborhood-based projects, some of which have taken different forms, scaled back or scrapped altogether. One major part, the East Side Resiliency project, is being funded partly by a $338 million federal grant awarded during the Obama administration. Although not a measure originally outlined in The BIG U, the land-extending proposal announced earlier this month is just one portion of the larger effort to insulate the most vulnerable parts of Lower Manhattan with climate-resilient infrastructure.

According to scientists with the New York Department of Environmental Conservation, sea levels are projected to rise as much as six feet around New York City's coastline by 2100. (Due to warming ocean water, they've already risen a full foot since 1900.) By the 2050s, roughly 37 percent of property in Lower Manhattan will be vulnerable to storm surge with that number increasing to 50 percent by 2100 per a press statement released by the Mayor's Office.

Writes de Blasio in an op-ed for New York magazine:

We don't debate global warming in New York City. Not anymore. The only question is where to build the barriers to protect us from rising seas and the inevitable next storm, and how fast we can build them.

It [the proposed plan] will be one of the most complex environmental and engineering challenges our city has ever undertaken and it will, literally, alter the shape of the island of Manhattan.

As part of the proposal, dubbed the Lower Manhattan Coastal Resiliency project, many of the protective measures outlined in The BIG U — snazzy elevated parks and removable flood barriers included — will be realized over the next few years to the tune of $500 million dollars. But as de Blasio details, these projects just aren't feasible in certain parts of Lower Manhattan where there's no room to introduce flood-blocking infrastructure.

And so, in a mile-long area on the eastern tip of the island just south of the Brooklyn Bridge that includes the South Street Seaport and Financial District neighborhoods, the city plans to build outwards.

Lower Manhattan Coastal Resiliency Map Under a new proposal, the area of Lower Manhattan shaded in blue, which includes the historic South Street Southport and the Financial District, would extend further into the East River. (Image: New York City Mayor's Office)

As de Blasio describes, this ultra-dense part of the city also sits at a perilously low elevation just 8 feet above the waterline and is "so crowded with utilities, sewers and subway lines" that building barriers on existing land is essentially impossible. Justin Davidson, architecture critic for New York magazine, calls the area "an unpatchable hole in the city's coastal defenses."

"The new land will be higher than the current coast, protecting the neighborhoods from future storms and the higher tides that will threaten its survival in the decades to come," says de Blasio. "When we complete the coastal extension, which could cost $10 billion, Lower Manhattan will be secure from rising seas through 2100. We're going to build it, because we have no choice."

More room for private development? That all depends

No doubt pushing the southeastern shoreline of Lower Manhattan closer to Brooklyn will yield a decent amount of available, highly covetable real estate that didn't exist before. And this certainly isn't the first time new land has been tacked on to the island.

Just around the bend on the southwestern tip of Manhattan where the Hudson River meets the Upper New York Bay, there's an entire 92-acre planned residential community, Battery Park City, that was built atop soil and rock reclaimed from the excavation of major construction projects in the 1970s and 80s including the World Trade Center as well as sand dredged from the harbor.

Damage after Hurricane Sandy, Lower Manhattan Lower Manhattan was one of the areas of New York City hit hardest by Hurricane Sandy's storm surge. (Photo: Stan Honda/AFP/Getty Images)

But as mentioned, the sizable swath of new land that could someday jut into the East River is not being touted as the future home to a privately developed, Hudson Yards-style enclave of glittering glass high-rises. Any additions will be dedicated to parkland and the same type of protective infrastructure projects that would have been built along the existing shoreline, had there been room to accommodate them. But that could change.

As an unnamed source told Gothamist of the plan in the days leading up to its official release, it's not entirely clear if all development will be forbidden at the freshly annexed sections of the Seaport and Financial District considering the astronomical cost involved with increasing the physical footprint of Lower Manhattan. "It's safe to say that this is going to have to be a public-private partnership," explains the source, adding: "This is going to be a resiliency measure first and foremost."

As Amy Plitt reports for Curbed, de Blasio himself has said that some public-benefitting development, including parks and schools, is "possible" as will be the creation of new streets. Large-scale private development will only enter the picture if the city is not able to finance the massive undertaking exclusively with state and federal funding, as it hopes to do.

"If there's federal money in play it probably looks one way," de Blasio explains. "If there's not federal money in play, we have to get some private money into it and there has to be some development."

De Blasio, however, has been quick to dismiss comparisons of his administration's proposal to then-Mayor Michael Bloomberg's highly controversial Seaport City scheme from 2013. Modeled heavily after Battery Park City, Bloomberg's plan encompassed a larger geographic area than what's been floated by de Blasio and focused more on glitzy private development a la Hudson Yards than integrated flood protection. But as Davidson notes for New York, this retooled version of Seaport City does "raise the specter of an offshore Hudson Yards."

"The prospect of creating new acreage within shouting distance of Wall Street could quickly turn an environmental tool into a real estate boondoggle," he writes.

South Street Seaport, post-Sandy Manhattan's tourist-snaring Sea Street Seaport district was among the precariously low-lying areas of Manhattan badly battered by Hurricane Sandy in 2012. (Photo: Spencer Platt/Getty Images)

The clock is ticking

The New York City Economic Development Corporation (NYCEDC) along with the Mayor's Office of Resiliency and Recovery (ORR) will spend the next two years ironing out a Financial District and Seaport Climate Resilience Master Plan, which, as the mayor's office points out, "will include a comprehensive design for the shoreline extension and establish a new public-benefit corporation to finance, construct, and manage it."

In the meantime, smaller, localized climate resiliency projects will move forward, including the reconstruction of Battery Park City's esplanade and installation of deployable "flip-up" flood barriers in the Two Bridges neighborhood.

"Protecting New York City from the threat of climate change requires big ideas," says Manhattan Borough President Gale A. Brewer. "The plan for land expansion in Lower Manhattan is a big idea, and kicking off a robust community engagement plan is critical to the success of this or any other idea that moves forward. I look forward to working with the administration along with the community to fully explore how this plan will both protect and be an asset for New Yorkers every day."

While numerous city leaders such as Brewer have praised the de Blasio administration's bold $10 billion proposal, some have questioned if it is simply too complex — and too expensive — to realistically come to fruition when considering the urgency at hand and the current political climate.

Relatedly, there are understandable worries about the potential for private real estate development to enter the picture. As Davidson notes, a scenario without private development — the one idealized but not guaranteed by the de Blasio administration — all "depends on whether the federal government comes back around to seeing climate protection as a national security issue."

New Yorkers might already be underwater by the time they stop holding their collective breaths waiting for that to happen.

South Street Seaport looking towards Brooklyn Heights One day, you may not have to strain your eyes quite as hard when taking in views of Brooklyn Heights from Manhattan's South Street Seaport. (Photo: Drew Angerer/Getty Images)

"With this plan to provide protection for the entire coastline of Lower Manhattan, we now have a roadmap to a more resilient and sustainable future," says Margaret Chin, a city council member representing New York City's District 1, in a statement. "However, this more resilient future cannot be paid for by private real estate development that would destroy the waterfront neighborhoods that we are trying to protect."

Others lament the fact that vulnerable waterfront communities in the Big Apple outside of Lower Manhattan aren't receiving the same amount of attention from the mayor's office. There are also concerns about the impact of pushing an entirely new land mass into an already narrow section of the East River, technically a 16-mile-long tidal estuary, will have on marine life.

Whatever the case, de Blasio does acknowledge that an uphill battle is ahead when it comes to securing federal funding from a fossil fuels-friendly presidential administration that's wildly antagonistic when it comes to battling climate change.

"Time is not on our side. This country has wasted too many years pretending it had the luxury of debating climate change," de Blasio concludes. "The national emergency is already here. We have to meet it head-on. And we need Washington behind us."

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

How making lower Manhattan larger will protect it from future flooding
Mayor Bill de Blasio's $10B climate resiliency plan would extend the Manhattan shoreline by as much as 500 feet into the East River.