An illustrated line-drawn map of the NYC water supply system including the watersheds, tunnels, and NYC.

This is a story that explores the complex history of New York City’s drinking watershed. The story will be told incrementally, beginning in geologic time, and ending where we are today.

This living document will grow over the course of a year—A Year of Public Water—from June 2020 to June 2021. Check back weekly for new content or follow #YearOfPublicWater on Instagram and Twitter.

Timeline / Table of Contents

Key  Underlined text: available content   Regular text: future content scheduled for release


550 Million Years Ago

The landscape takes form

The Manhattan Prong

In Geologic Time

Shallow Seas

The Pleistocene


9000 BC

Native Americans inhabit the land


Water system construction begins

Toxic Water, Part II

The Old Croton Dam

From Westchester to a Manhattan Potter’s Field


Becoming Boroughs



From the Housatonic to the Hudson – Two Plans Subsequently Scrapped

The New Croton Reservoir

Water Expansion by Eminent Domain, Part I

Water Expansion by Eminent Domain, Part II

Flooding the Catskills

Building The Ashokan Reservoir

Water Labor


Waste in the Watercourse

Under the Hudson

Removing Gilboa

From the Supreme Court to the Delaware

Tapping the Delaware River




The New York City Water Board

The Reagan Years


Contamination and Bottled Water

Alan Hevesi

DEP Watershed Regulations

1997 New York City Watershed Memorandum of Agreement

International Water Infrastructure Privatization, Part II


International Water Infrastructure Privatization, Part III

Mismanaged Water Infrastructure Privatization

The Water System Updates

Power Sharing and Participation, Part I

Power Sharing and Participation, Part II

Filtration, Part I

Filtration, Part II


The Present, Part I

The Present Part II

The Future

A Story About the NYC Drinking Watershed


June 29, 2020

The US is experiencing not only a substantial economic and public health crisis related to Covid-19 but an underlying public water crisis. Millions of people face obstacles to access safe, clean running water daily. Agricultural runoff, byproducts of disinfection agents, as well as aging infrastructure like lead pipes have contaminated drinking water, especially in minority and low-income communities. In 2014, the city of Detroit began disconnecting residents’ water as part of a debt-collection program, and has since disconnected over 141,000 households in an act that the United Nations deemed a human rights violation. Infrastructure repairs, environmental clean-ups, and water privatization have all led to higher costs for individuals. While the cost for water has been rising around the US, the billion-dollar bottled water industry continues to use public water sources at unimaginably low costs for their products. (The Guardian, June 23, 2020)

Last month, additional EPA regulations were rolled back, this time Section 401 of the Clean Water Act. Section 401 gives states and First Nations veto power over industry projects that would impact local populations. These rollbacks make it easier for industries to frack, mine, and build pipelines in sensitive areas. This will affect land, air, and water, creating additional environmental sacrificial zones (mining and fracking have been found to heighten drinking water contamination risk from toxins like benzene, diesel, heavy metal pollution, cyanide and sulphuric acid to name some).

New York and surrounding states have used Section 401 to protect residential drinking water numerous times, including by creating high profile projects like the Constitution Pipeline and the Northeast Supply Enhancement Pipeline. Addressing environmental, health, and economic conditions in and around New York City’s watershed is a vital precondition for the creation of a more just present and future for urban and rural New Yorkers.

The Manhattan Prong 

The Manhattan Prong was formed approximately 550 million years ago and extended all the way to southwest Connecticut (from the Algonquian Quinnitukqut meaning “at the long tidal river”). Its formation consisted of rolling hills and valleys, controlled by the underlying bedrock. Much of the bedrock was covered by Atlantic Coastal Plain deposits. Metamorphic rocks resistant to erosion comprised the hills, including the Fordham and Yonkers Gneiss, the Lowerre Quartzite, and the Manhattan Schist. The Hudson, Harlem, and East Rivers and the major north-south valleys in (what is now often referred to colonially as) northern Westchester County are all underlain by easily-erodible Inwood Marble formed from the metamorphosing of shallow water marine carbonate and clastic sediment. The formation of Inwood marble extended to the Inwood section of northern Manhattan. The rocks of the Manhattan Prong were tightly folded and metamorphosed primarily during the Taconian Orogeny, about 450 million years ago.

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In Geologic Time 

Much of New York State’s bedrock and the Adirondack Mountains were formed by ancient Precambrian crystalline basement rock forms. About 450 million years ago the biotite-rich bedrock (made of gray quartz and white orthoclase) known as the Manhattan Schist transformed from shale to metamorphic rock, and constituted part of Manhattan (from the Munsi language of the Lenni Lenape/Delaware “island of many hills”) during continental collision between the floor of the present-day Atlantic Ocean, and what would later be known as the East Coast of North America. In the area often referred to as midtown Manhattan, the bedrock lies within a few feet of the ground’s surface, and within 40 feet of the surface in lower Manhattan making skyscrapers possible, whereas accessing the bedrock was (and still is) cost-prohibitive at a depth of 4-5 times deeper in other parts of so-called New York City.

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A line drawing map of the supercontinent Rodinia
Shallow Seas 

During the Paleozoic Era, parts of the region were uplifted to form the Allegheny Plateau (a physiographic section of the larger Appalachian Plateau province). Other areas nearby were flooded by shallow seas depositing sedimentary rock sequences. Stream erosion crossed the plain and carved away all of the rock except the harder stone of the higher peaks of the Catskill Mountains, which all have about the same elevation today.  Much of the rocks in the Catskill Mountains were deposited by rivers near sea level, and are com­posed of Devonian-aged sed­i­men­tary bedrock (sand­stones, shales and con­glom­er­ate formed in ancient river val­leys). The green and red­ striated clays visible on the edges of stream ­banks are ancient glacial lake deposits eroded from siltstones and shales that contain fossil remains of plants, clams, and insects from the Devonian Period.

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A map of New York State with geologic areas color coded, eg. Atlantic Coastal Plain, Adirondack Mountains, Manhattan Prong.
The Pleistocene

Fast forward to 2.6 million years ago and in the Pleistocene Epoch glaciers carried along vast amounts of sands, soils, gravel, and boulders leaving deposits up to 300 meters thick in some valleys. This left the Catskill region low and flat, and hollowed existing trenches as mammoth ice sheets repeatedly advanced across New York State. The towering ice widened and expanded former river valleys to make the Finger Lake troughs. Some of the finger lakes were pushed down so deeply by these glaciers that their earlier bedrock floors lie below sea level.

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A satellite photo of the Finger Lakes region of NY with regions covered in snow

While it took 3.8 billion years to sequester minerals that surround what is still commonly referred to as New York City and build a baptismal freshwater flow, it took less than 100 years of industrial experimentation to corrupt it, and more than 150 years to build a public water system that’s been continually in process…

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A photo of outcrops of rounded Stromatolite forms in a shallow pool of seawater
Stromatolites at Lake Thetis, Western Australia. Image Credit: Ruth Ellison / Creative Commons.
Colonization and the Power of Language

At the time of European contact in the 16th and 17th centuries, the Wappingers and Canarsee inhabited Manhattan Island in semi-permanent settlements. They were Eastern Algonquian-speaking subgroups of the Algonquian peoples. The Lenni Lenape once occupied most of the northeast coast and Westchester, Putnam, and Dutchess Counties as well as the land between the Delaware and Hudson Rivers—this is known as Lenapehoking, meaning Land of the Lenape. As the myth goes, the Dutch “purchased” Manahatta island from the Canarsee Lenape in 1626. The Canarsee likely viewed the “sale” of Manhattan as a deal to share the land, but not to sell it. The transaction, enforced by the eventual building of a wall around what the Dutch had renamed as New Amsterdam, marked the very beginning of a forced mass migration of the Lenni Lenape from their homeland. The wall, which started showing up on maps in the 1660s, was built to keep the Native Americans and the British out. It eventually was renamed Wall Street, and Manahatta was renamed Manhattan (Smithsonian). Lenni Lenape placenames including Gowanus, Hackensack, Manhattan, Passaic, Rockaway, and Weehawken make up the toponymy of metropolitan New York. 

The Lenni Lenape of the Eso­pus (including Catskill, Mamekoting, Waranawonkong, and Wawarsink) lived within the water­shed and began encoun­ter­ing Dutch set­tlers in the early 1600’s. Later, waves of immi­grants settled in the area. The new arrivals slowly pushed Native Americans from these ances­tral lands. Historians have traced the beginning of water privatization to around the same time as in Malvern, England. There, spring water was first bottled on a commercial scale at The Holy Well. During the second Anglo-Dutch War, New Amsterdam was renamed New York to honor the Duke of York. The Duke of York later became King James II of England and James VII of Scotland. In 1667, the first public well was dug in front of Bowling Green, New York.

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A map of lower manhattan in the 1600s.
A 1664 map of New Amsterdam, now lower Manhattan. The wide street is now Broadway, and Wall Street is the line with guard towers. Broadway formed from the trails of the Lenape trade route known as the Wickquasgeck trail, named after the Wickquasgeck people, a sub-tribe of the Wappingers who inhabited north Manhattan. The trail was named Brede weg, and later Broadway.
Toxic Water, Part I

While New York City’s water is now touted as some of the cleanest, unfiltered water, this was hardly the case in the 1600’s. The first well dug in 1667 pumped briny water, so most people drank from the Collect, which was the region’s main freshwater source. However, the Collect eventually became a site to dump chamber pots, dead animals, and tannery waste. It became so polluted the city paved over it, becoming Paradise Square, then Five Points, now Collect Pond Park. In the early 1700’s cleaner water was arduously transported from Brooklyn to Manhattan, which was tapped from wells in Brooklyn and western Long Island. While Brooklyn had an adequate supply of clean groundwater, it could not meet the needs of both Brooklyn and Manhattan residents. As the city’s population increased through the 19th century, more wells were dug without separate systems for sewage and garbage. Additionally, the wells that were dug to tap groundwater were stone-lined and became contaminated with salt water from the Hudson and East Rivers.

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A view of Collect Pond and Its vicinity in 1793 (cropped from a 1846 broadside issued by John Hutchings). Note the water pump landmarked on the right side of the map, and the two tan yards located at the pond’s edge at Pearl Street and Anthony Streets.
Toxic Water, Part II

Further fueling the quest for clean water, the foul quality of Manhattan’s water supply caused epidemics of yellow fever (the first of six epidemics killed nearly six percent of the population) and cholera. (The cholera outbreak was caused by the bacterium Vibrio cholerae, often found in contaminated water.) On June 26th, 1832 the first cholera outbreak struck Manhattan. Wealthy New Yorkers fled to the country to avoid infection (about one third of the population), leaving mostly immigrants and low-income families. More than 3,500 people died, with the first of many deaths in the Five Points neighborhood (current day Foley Square and Chinatown), where many Irish-Catholic immigrants and African Americans lived. The need for a new supply of fresh water for residents was crucial.

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A stereoscopic black and white photograph of a street in Five Points. The view looks down the middle of a dirt covered street with horse-drawn carriages and stores.
Stereoscopic view of the Five Points area. Source: The Miriam and Ira D. Wallach Division of Art, Prints and Photographs: Picture Collection, The New York Public Library Digital Collections. Issued in 1870.

Around the same time, much of New York’s Catskill Mountain region and the Ashokan Watershed area had become central to resource extraction. Tanneries would be supplied by the area’s verdant hemlock trees, while charcoal kilns and quarries sprung up along rivers, creeks, lakes, streams and expanding trade routes.

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A photograph of a factory with tanning baths covering the floor of the space in a grid formation. In
Tan Yard. Endicott Johnson Plant, Endicott NY. 1917. Source: New York State Archives. Education Dept. Division of Visual Instruction. Instructional lantern slides, ca. 1856-1939. Series A3045-78, No. 9967.
Privatization, Part I: International Water Infrastructure

Internationally, a procession of water giants began to surface: Suez, Veolia, and Thames were among them. The dissolution of land-based commons (and with it, appropriation of many peoples sustenance) was perceived essential for the industrial revolution to provide the amount of “natural resources” to process raw material into industry. Commoditization of land, water, forests, fisheries, seeds, and knowledge had propelled a particular logic of privatization which would later become a crucial aspect of free trade ideology.

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A photograph of a man-made canal/river flanked by grassy green meadow. Homes can be seen in the distance. A footbridge crosses over the river and two white swans are swimming in the water about to go under the bridge.
The New River at Hertford, 2013. Thames Water, the UK’s largest water and wastewater services company, can trace its history back to the building of the New River, from 1609 to 1612, which channelled fresh water from Hertfordshire to the New River Head in Islington. Source: Image via Flickr, Jayembee69
Privatization, Part II: Hamilton, Burr, and the Manhattan Company

Manhattan’s drinking water went through several privatization schemes as early as the 18th century. These were led by two State Assemblymen, Alexander Hamilton and Aaron Burr. Burr convinced city officials that public funds would be inadequate to develop a suitable reservoir and aqueduct. He created the Manhattan Company (later to become Chase Bank) to serve the public as the sole supplier of water and took control of the city’s water system in 1799. However, hidden in the bill that granted a charter to the Manhattan Company was a clause that stated that the company could use any surplus capital for other purposes. The company was expected to tap into the Bronx River but instead drilled wells into the polluted Collect Pond, which was much cheaper. Additionally, the company only laid 23 miles of pipes and charged an expensive rate of 20 dollars a year, which made it inaccessible to many citizens. Two thirds of the population still relied on polluted wells or buying spring water from expensive private vendors. Because of these failures, in 1816 several Common Council committees were appointed to investigate whether the legislature could grant the city the right to build a public water supply; however, nothing immediate was done about the toxic water and poor service. The first changes began around 1828 after repeated fires destroyed blocks because water mains and fire hydrants had not been extended to all parts of the city.

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A watercolor illustration of a white 2-story sized building with greek-like columns. The building is flanked by two colonial style residential buildings. The street in front shows a few people and a horse and buggy.
Manhattan Company Reservoir on Chambers Street, watercolor, G.P. Hall & Sons, 1825. Source: waterworkshistory.us and Museum of the City of New York.
The Old Croton Dam

After exploring alternatives, in the late 1820’s, city officials made plans to extract water from the Croton River in Westchester County. The development of the city’s first successful public water supply system was a major engineering undertaking, constructed by almost 4,000 immigrants. The Old Croton Dam created a lake about 400 acres in size. The dam received considerable pushback from Westchester residents, who argued that it “disfigured their fields and divided property.” Water started flowing through the aqueduct on June 22, 1842, bringing water 41 miles from the Croton River to reservoirs in Manhattan. This changed domestic life in the city. Baths and running water were built in the private homes of wealthy New Yorkers, and public bathing facilities were constructed for everyone else. However, the decline in the number of residents drawing water from the city’s wells rose the water table and created floods. In an effort to further sanitation, city agencies also built sewers in many residential streets.

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A map of Westchester with counties in different colors. Includes property owners names.
Map of Westchester County, NY from actual surveys. Issued 1858.
Source: Library of Congress. Link.

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