For most of human history, turning a handle and getting clean water has been a miracle that nobody notices. But in the early 19th century, New York City discovered what happens when that miracle fails. Surrounded by water on every side, the island of Manhattan was dying of thirst and disease. By 1832, the city had been poisoned by its own waste, and when cholera arrived that summer, it killed more than 3,500 people in a single season out of a population of roughly 250,000.
Cholera was a horrifyingly fast killer. A person could be healthy at breakfast and dead by nightfall. New Yorkers called it the “destroying angel,” but nobody knew what caused it. The best medical minds blamed bad air, a mysterious poison they called miasma.
It would be another two decades before anyone proved that the disease actually traveled through contaminated water. In the meantime, the poor kept drinking from the same polluted wells, and they died by the thousands. Around 100,000 residents, nearly a third of the city, fled to the countryside to escape the outbreak. The city’s water supply had been a disaster for decades.
The main source of drinking water was a pond near the southern tip of Manhattan called the Collect Pond, which had once been clean enough for fishing and ice skating. But tanneries, slaughterhouses, and breweries lined its banks and poured their waste directly into it. Within a generation, the pond went from the city’s water supply to its open sewer. In 1799, the state gave the job of supplying water to a private company led by Aaron Burr, the same man who would later shoot Alexander Hamilton in a duel.
Burr’s Manhattan Company skipped the expensive plan to bring clean water from outside the island and instead sank more wells near the polluted pond, piping the water through hollowed-out logs. A clause in the company’s charter allowed him to use leftover funds for other business, so he took the surplus and started a bank, which through mergers eventually became part of what is now JPMorgan Chase. The water remained filthy, but the bank did beautifully. It took a second disaster to finally force change.
On December 16, 1835, a fire broke out in a warehouse in lower Manhattan on one of the coldest nights anyone could remember, with temperatures around 17 degrees below zero. Every water source the firefighters reached was frozen solid. Even the East River had ice over it, and the water froze inside the hoses in the men’s hands. The Great Fire of 1835 destroyed around 674 buildings and leveled much of the commercial core, causing roughly $20 million in damage.
The lesson was impossible to ignore: a city without water could not save itself from disease or from fire. The engineers went looking for a river. They found the Croton River about 40 miles north in Westchester County. It ran clean and sat higher than the city, which meant that if a channel were built with a gentle enough slope, gravity would carry the water the entire distance with no pumps at all.
The man who made the plan real was John B. Jervis, a largely self-taught engineer who had started as an axeman clearing brush on the Erie Canal. He designed a closed masonry channel shaped like an egg standing on end, about 8. 5 feet tall and 7.
5 feet wide, with a slope of just 13 inches of drop for every mile. Over 41 miles, that gradient had to hold perfectly through hills and valleys. The aqueduct was built by roughly 4,000 workers, the great majority of them Irish immigrants who took the hardest manual labor because it was the work no one else would do. They lived in rough shanty camps, worked from before dawn until after dark, and were paid low wages.
There were strikes when pay was cut or held back, and they were put down hard. The engineer’s name is remembered on the plans, but the 41 miles of stone were put into the ground by thousands of Irish hands whose names were mostly never recorded. The work also fought the river itself. In early January 1841, with the dam holding back the Croton nearly finished, heavy rain on top of snow caused the earthen embankment to give way.
A wall of water and ice up to 50 feet high swept down the valley, destroying mills, bridges, buildings, and taking lives. The engineers did not walk away. They rebuilt the dam in masonry with a curved spillway designed to break the force of the water, so the river could never destroy their work again. To get to Manhattan, the water had to cross the Harlem River.
Jervis built the High Bridge, 15 massive stone arches stretching nearly 1,450 feet across the valley, carrying the water pipes high above the river so ships could pass underneath. It took nearly 10 years to finish and was not completed until 1848, six years after water first reached the city. The High Bridge is still standing today. It is the oldest bridge in New York City, older than the Brooklyn Bridge by decades, and people can still walk across it.
Once the water crossed the Harlem River, it flowed into a receiving reservoir on the west side of Manhattan, between what are now 79th and 86th Streets. That reservoir is long gone, and the ground it covered is now the great lawn and Turtle Pond in the middle of Central Park. From there, the water ran to a second reservoir on Fifth Avenue between 40th and 42nd Streets, built to look like an Egyptian temple with granite walls 50 feet high and 25 feet thick at the base. It held around 20 million gallons of water, and a public promenade along the top of the walls became one of the most fashionable places in the city.
When the reservoir was torn down at the end of the century, the main branch of the New York Public Library was built on its exact footprint. The two stone lions out front now sit where the water once was. On June 22, 1842, they let the water go. It traveled at a walking pace of under two miles an hour, falling only downhill the entire 41 miles, and took about 22 hours to reach the city.
They admitted the water into the reservoir at 42nd Street on July 4, and the city celebrated its independence and its water on the same day. The real celebration came on October 14, 1842, when New York threw a parade roughly seven miles long. Bands, fire companies, trade societies, and civic groups marched in the tens of thousands. Former Presidents John Quincy Adams and Martin Van Buren, sitting President John Tyler, and the governor of New York all attended.
At the center of it all, in the park by City Hall, a fountain shot a jet of clean Croton water 50 feet into the air. Many people wept at the sight of clean water thrown into the sky purely for joy. The aqueduct did not by itself end disease. Cholera returned in 1849 and killed thousands again, because nobody yet understood that the disease lived in the water.
It would be more than a decade before London doctor John Snow proved that cholera travels through the water supply. But the aqueduct laid the foundation for everything that followed. It gave the city more clean water than it could use, allowed the poisoned wells to be closed, and made sewers, indoor plumbing, public baths, and working fire hydrants possible. The old Croton Aqueduct carried water to the city until the early 1900s, when a second, even larger system was built beside it.
The High Bridge still stands, and the line of the old aqueduct is now a walking trail through Westchester. Underneath the path, the egg-shaped stone channel remains in the ground, laid by Irish hands in the 1840s. Modern New York still drinks water that flows by gravity from reservoirs up north, arriving the same way the Croton water did, downhill on its own, on the principle proven by a self-taught canal man over 41 miles of hand-laid stone in 1842.