Lower Manhattan expansion
The expansion of the land area of Lower Manhattan in New York City by land reclamation has, over time, greatly altered Manhattan Island along the shorelines of the Hudson and East rivers; as well as those of the Upper New York Bay. The extension of island's landmass began with European colonialization and continued in the 20th century. Incremental encroachment as well as major infrastructure have added acreage to the island. Since the passage of the Rivers and Harbors Act of 1899 all projects which extend into navigable waterways follow federal regulation and are overseen the United  States Army Corps of Engineers. The original shoreline on the East Side generally ran along contemporary Pearl and Cherry streets and on the West Side was roughly today's Greenwich Street. Encroachment began in the 17th-century Dutch settlement of New Amsterdam. The real estate law mechanism of "water lots" encouraged commercial land growth through the Dongan Charter of 1686 and the Montgomerie Charter of 1731. By the 19th century of land had been created by landfill, the disposal of waste During this period, for example, the East River waterfront had shifted to Water Street (1730), Front Street (1780), and  finally, South Street (1800). By the early 20th century the expansion had obliterated the extensive oyster beds which once covered much of the estuary floor. It is estimated that by the 1970s, 1400 to 2225 acres of the entire Manhattan landmass, has been created by reclamation. Another estimate is that 3,000 acres, or 29% of the entire Manhattan landmass, had been created by reclamation. In the 21st century, largely in response to Hurricane Sandy and a lesser degree Hurricane Ida, projects along the shoreline have been proposed as part of climate change adaptation to mitigate the effects to Manhattan Island  by improved resilience. A 2014 plan known as the BIG U by Bjarke Ingels Group largely involved constructing a series of berms in Lower Manhattan inland from the shoreline. but has in part been deemed inadequate and too costly to maintain. More utopian proposals for a drastic expansion encompassing Governors Island have circulated since the early 20th century, forming a kind of sixth borough. The Battery. In 1683, the British built platforms of dirt off the island's southern tip for military defense, and again in 1735 as the "Copsey Battery". The remains of Fort George/Amsterdam was used for  expansion of the Battery in 1788. Castle Clinton was built on a small artificial island just off shore. Construction began in 1808 and the fort was completed in 1811, though modifications continued through the 1820s. The Battery was mostly created by landfill starting from 1855, using earth from street-widening projects in Lower Manhattan which united Castle Garden's island with the "mainland" of Manhattan. The original shoreline is roughly the modern-day park's eastern boundary at State Street. FDR Drive and East River Park. FDR Drive was built along the East River shore in the 1930s using embankments  and pilings. East River Park was built on landfill. In December 2019, the New York City Council voted to approve the controversial $1.45 billion East Side Coastal Resiliency (ESCR) project, involving the park's complete demolition and subsequent renovation. Battery Park City. In the 1960s–1970s, landfill was used in the creation of that comprise Battery Park City. The initial utilized cubic yards of material from excavations for the construction of the original World Trade Center Additional fill came from other construction projects such as New York City Water Tunnel and the dredging of the Kill Van Kull. South Street -East River proposals. In 2013, then-mayor Michael Bloomberg proposed a "Seaport City" similar to Battery Park City for the area around the South Street Seaport. In 2019, as part of part of plan to mitigate potential damage due to climate change to South Street Seaport and the Financial District, his successor Bill de Blasio proposed creating upwards of of land reclamation from South Street into the East River south the Brooklyn Bridge. In 2021, the City of New York introduced the Financial District-Seaport (FidiSeaport) Resilience Plan for a stretch of what is seen as the most complicated and  vulnerable reach of shoreline in Lower Manhattan. Construction would incorporate floodwalls, floodgates, pumps, and other water management techniques to handle tidal flow, flooding and stormwater and extend to into the river. Proposals including Governors Island. Canadian-American engineer T. Kennard Thomson first made an expansive proposal for "A Really Greater New York" in 1911, incorporating a lower Manhattan expansion into Governors Island (at that time undergoing land reclamation itself) as "New Manhattan", as well as other ambitious designs such as new Lower New York Bay islands, and filling in and creating new rivers. One of his goals was to halt  the historical march uptown, which was seen as detrimental to downtown businesses. Thomson made different versions of this idea through the years, forming a "Manhattan Extension" corporation in 1921 with support from prominent former judge and presidential candidate Alton B. Parker as well as the artist Walter Russell, and continuing advocacy for the rest of his life. A century after Thomson's initial idea, a 2011 proposal by Vishaan Chakrabarti, a professor at Columbia University's Center for Urban Real Estate, suggested using land fill to connect lower Manhattan and Governors Island, so creating a new neighborhood referred to as  LoLo (Lower Lower Manhattan). Chakrabarti and others pointed out challenges to the proposal, which include cost, the strict regulations surrounding building with landfill, and the potential environmental effects of the project. The proposal was revisited in 2015 by author Jon Methven of "The Awl", in which he referred to the proposed borough as "Frankenborough". A 2022 proposal along these lines by Jason Barr of Rutgers University called for a "New Mannahatta". This proposal was criticized by Willy Blackmore in "Curbed" on environmental grounds.