The Simple Genius of NYC’s Water Supply System

Summary

This script explores New York City's complex water supply system, highlighting its challenges due to geographical constraints and the city's rapid growth. It details the city's reliance on distant reservoirs in the Catskill Mountains, the remarkable engineering feats of the unfiltered water delivery system, and the ongoing efforts to maintain water quality and infrastructure. The narrative underscores the simplicity yet costliness of the system, which is crucial for the city's sustenance and success.

Takeaways

• 🏙️ New York City, despite being surrounded by water, faces water scarcity due to the lack of accessible fresh water sources in its immediate landscape.
• 🌊 The East River and Hudson River, while significant, are tidal estuaries and not reliable sources of fresh water for the city's consumption.
• 🏞️ Manhattan's early freshwater source, Collect Pond, was eventually rendered unusable due to pollution from industrial activities.
• 🚰 The city's water supply became insufficient for its growing population, necessitating the development of infrastructure to import water from further away.
• 🛣️ The Ashokan Reservoir and the Catskill mountain landscape serve as critical water sources for NYC, with a vast storage capacity and a significant watershed.
• 💧 The Delaware/Catskill water system is the largest unfiltered water supply in the US, relying on natural processes for water purification.
• 👮‍♂️ The New York City Department of Environmental Protection (DEP) enforces strict regulations on land use and water quality in the watershed to ensure water safety.
• 🔬 The DEP employs a large workforce of scientists and engineers to monitor water quality and collaborate with local communities to prevent pollution.
• 🌡️ Robotic buoys and labs perform continuous water quality tests, including turbidity and the presence of waterborne pathogens.
• 🚰 The city's water transportation system includes two of the world's largest aqueducts, capable of delivering vast quantities of water to NYC.
• 🛠️ The Delaware Aqueduct, the world's longest tunnel, operates like an inverted siphon, utilizing physics to transport water to NYC without external forces.
• 🏗️ The city's aging water infrastructure, including tunnels and water mainlines, requires significant maintenance and faces challenges such as leaks and breaks.
• 🔄 The DEP adds various chemicals to the water for purification and health benefits, such as chlorine, fluoride, and orthophosphate, adjusting treatments based on real-time water quality issues.

Q & A

Why is New York City considered water-scarce despite being surrounded by waterways?

New York City is water-scarce because the waterways surrounding it, such as the East River and the Hudson River, are tidal estuaries with undrinkable salt water, and the city's landscape lacks a significant supply of fresh water.

What is the significance of the Collect Pond in the history of New York City's water supply?

Collect Pond was the major freshwater source for early settlements in the area, but it became unusable due to pollution from tanneries, breweries, and other industries, highlighting the city's struggle with water supply even in its early days.

How does the Ashokan Reservoir contribute to New York City's water supply?

The Ashokan Reservoir is part of New York City's infrastructure that stores a large volume of water, receiving rainfall and drainage from a vast area of the Catskill Mountains, and is closely monitored for water quality.

What is unique about the water supply system of the Delaware/Catskill system?

The Delaware/Catskill system is the largest unfiltered water supply in the US, relying on the natural filtration provided by the landscape and strict protection of the watershed to maintain water quality.

How does New York City ensure the protection of its water supply from contamination?

New York City uses the New York City Department of Environmental Protection to monitor and protect the water supply, employing scientists, engineers, and a police force to patrol the watershed and enforce regulations.

What is the role of the Catskill Aqueduct in transporting water to New York City?

The Catskill Aqueduct is a series of dams, tunnels, and siphons that can move half a billion gallons of water daily over a distance of 92 miles to the south, playing a crucial role in the city's water supply.

Why is the Delaware Aqueduct considered an engineering marvel?

The Delaware Aqueduct is an engineering marvel because it is the world's longest tunnel at 85 miles and operates like a giant inverted siphon, transporting water to New York City without the need for external forces.

What challenges does New York City face with its aging water infrastructure?

New York City faces challenges such as leaks, breaks, and the need for repairs in its aging water infrastructure, which includes tunnels and water mainlines that are decades old and require significant maintenance.

How does the DEP add chemicals to the water supply to ensure its safety?

The DEP adds chemicals such as chlorine to kill microorganisms, fluoride to combat cavities, orthophosphate to limit lead leakage, and sodium hydroxide to balance pH levels, with some additives adjusted based on real-time water quality issues.

What is the significance of the Croton watershed in New York City's water supply?

The Croton watershed supplies about 10% of New York City's water and is unique because its water requires filtration, unlike the water from the Catskill/Delaware system.

How does the DEP ensure the continuous supply of water during the planned shutdown of the Delaware Aqueduct?

The DEP ensures continuous water supply by relying on the Catskill Aqueduct to operate at full capacity and by increasing the supply from minor sources like the Croton Aqueduct during the shutdown period.

Outlines

00:00

💧 Water Scarcity in New York City

New York City, despite its location in a rainy region and surrounded by waterways, faces water scarcity due to the lack of accessible freshwater. The East River and Hudson River are estuaries affected by seawater, rendering them unusable. The city's early water source, Collect Pond, became polluted due to industrialization. The small watershed of Manhattan could not sustain the growing population, necessitating reliance on external water sources. The Ashokan Reservoir, located in New York but far from the city, is a critical water storage facility, part of a vast, unfiltered water supply system that requires significant oversight and coordination to maintain water quality standards.

05:00

🚔 Protecting and Transporting NYC's Water

The New York City Department of Environmental Protection (DEP) employs a 200-officer police force to safeguard the water supply from contamination and security threats. The DEP also uses scientists and engineers to monitor water quality and work with local communities to minimize pollution. The city's water must travel significant distances through large aqueducts, such as the Catskill Aqueduct and the Delaware Aqueduct, which is the world's longest tunnel and operates like an inverted siphon, moving water to the city without the need for external energy. However, the aging infrastructure, including leaks in the Delaware Aqueduct, presents ongoing challenges that require extensive planning, construction, and financial investment.

10:01

🛠 Treatment and Delivery of NYC's Water Supply

At the Kensico Reservoir, the water is first treated with chlorine and other chemicals to ensure safety and quality. The DEP adds fluoride, orthophosphate, and sodium hydroxide to the water to improve health, prevent lead leakage, and balance pH levels. The Catskill-Delaware Ultraviolet Water Treatment Plant further treats water using UV light to eliminate pathogens. In contrast, water from the Croton watershed requires filtration due to its lower quality. The water is then transported through a vast network of tunnels and water mainlines to reach consumers, with the DEP continuously monitoring and testing water quality across the city. The aging infrastructure, including old tunnels and water mains, requires significant maintenance and presents challenges for the city's water supply system.

15:05

🏙️ The Complexity and Cost of NYC's Water System

New York City's water system, while simple in concept, is complex and expensive to maintain. The city's foresight in recognizing the importance of a reliable water supply has led to the creation of billion-dollar projects and record-setting structures. However, the simplicity of the system's design has resulted in high dependency on a limited number of critical infrastructures, such as the two main aqueducts. The cost of maintaining and upgrading this infrastructure is immense, with ongoing projects like Tunnel number 3, which has been under construction since 1970 and is expected to cost around $6 billion. Despite these challenges, New Yorkers take pride in their water, attributing its quality to the city's renowned pizza and bagels.

📚 Sponsor Spotlight: Learning Physics with Brilliant

The script concludes with a sponsor promotion for Brilliant, an educational platform focusing on interactive learning in STEM subjects. It emphasizes the effectiveness of learning by doing, as opposed to traditional text-based learning, and offers a discount for the first 200 subscribers who sign up through a provided link. The promotion highlights the platform's ability to help users understand complex subjects like the physics behind the Delaware Aqueduct, which is a significant part of New York City's water system.

Keywords

💡Water-scarce

The term 'water-scarce' refers to a situation where the availability of fresh water is insufficient to meet the demands of the population and environment. In the context of the video, New York City is described as water-scarce despite being surrounded by water bodies, because the water sources around it are either saltwater or polluted, highlighting the irony and complexity of the city's water supply challenges.

💡Tidal estuary

A 'tidal estuary' is a partially enclosed coastal body of water where freshwater from rivers and streams mixes with saltwater from the ocean. The script mentions the East River as a tidal estuary, emphasizing that it is not a river but a body of water connecting ocean portions and carrying undrinkable saltwater, which is crucial to understanding the limitations of New York City's natural water resources.

💡Freshwater

Freshwater is water with low concentrations of salts and other minerals, making it suitable for drinking and supporting freshwater ecosystems. The video discusses the Hudson River as a freshwater source but notes that its usability is limited due to tidal influences, which is a key point in understanding the city's water supply dynamics.

💡Watershed

A 'watershed' is an area of land that drains all the streams and rainfall to a common outlet such as a river. The script refers to Manhattan's small watershed, which is insufficient for its growing population, indicating the importance of water catchment areas in supplying water to urban areas.

💡Collect Pond

Collect Pond was a historical freshwater body in what is now New York City's Chinatown. The script describes it as the area's sole major freshwater source before it became polluted due to industrial activities, illustrating the historical challenges of water management in urban environments.

💡Reservoir

A 'reservoir' is an artificial lake or natural basin used to store water. The Ashokan Reservoir mentioned in the script is part of New York City's water supply infrastructure, highlighting the city's reliance on large-scale engineering projects to manage its water scarcity.

💡Unfiltered water supply

An 'unfiltered water supply' refers to water that is not passed through a filtration system to remove impurities. The video takes pride in the Delaware/Catskill system being the largest unfiltered water supply in the US, which requires extensive monitoring and protection to ensure water quality, underscoring the unique challenges and measures taken by New York City.

💡Aqueduct

An 'aqueduct' is a conduit for conveying water from one place to another, often over long distances. The script details the Catskill Aqueduct and the Delaware Aqueduct, which are essential for transporting large volumes of water to New York City, showcasing the engineering marvels that address the city's water needs.

💡UV Water Treatment

UV Water Treatment involves using ultraviolet light to disinfect water by destroying microorganisms. The script mentions the Catskill-Delaware Ultraviolet Water Treatment Plant, which is the world's largest of its kind, emphasizing the advanced technology used to ensure water safety in New York City.

💡Water mainlines

Water 'mainlines' are the primary pipes that carry water from the source to distribution points. The video discusses the extensive network of nearly 7,000 miles of water mainlines in New York City, which are crucial for delivering water to millions of consumers, but also highlight the infrastructure challenges and costs associated with maintaining them.

💡Water quality

Water 'quality' refers to the purity and safety of water, which is a critical aspect of public health. The script describes how New York City adds various chemicals and minerals to the water to improve its quality and uses UV treatment, reflecting the city's commitment to providing clean and safe water to its residents.

Highlights

New York City is paradoxically water-scarce despite its location in a rainy region and being surrounded by waterways.

The East River and Hudson River are tidal estuaries, making them unusable for fresh water supply.

Manhattan's early water source, Collect Pond, was rendered unusable due to pollution from surrounding industries.

New York City's water supply relies heavily on the Catskill mountain landscape, with reservoirs having a 2 trillion-liter storage capacity.

The city's water system is the largest unfiltered water supply in the US, relying on natural processes for water purification.

New York City has regulatory power over land use in the watershed area to maintain water quality standards.

The New York City Department of Environmental Protection employs a 200-officer police force to patrol the watershed.

The DEP uses robotic buoys and labs for constant water quality monitoring in the reservoirs.

New York City consumes an Olympic-sized swimming pool worth of water every minute.

The Catskill Aqueduct is a massive engineering feat, capable of moving half a billion gallons of water daily.

The Delaware Aqueduct is the world's longest tunnel, operating like an inverted siphon to transport water to the city.

A leak in the Delaware Aqueduct resulted in tens of millions of gallons of water loss and contamination issues.

The Croton watershed supplies 10% of New York's water and requires filtration unlike the Catskill/Delaware system.

The Catskill-Delaware Ultraviolet Water Treatment Plant is the world's largest, treating over 2.3 billion gallons of water daily.

New York's water delivery system includes over 7,000 miles of water mainlines to connect to consumers.

The city's aging water infrastructure faces challenges with old and leaky tunnels and pipes.

Tunnel number 3, once completed, will be the city's single largest capital project, costing around $6 billion.

New York City's water system is an example of simplicity in design but requires significant foresight and investment.

Transcripts

New York is a water-scarce city.

Despite being surrounded on all sides by waterways and located in one of the rainier regions

of America, the landscape upon which it was built lacks a significant supply of fresh

water.

To Manhattan’s east, there’s the East River, but its name is a misnomer—it’s

not a river.

It’s a tidal estuary, connecting one portion of ocean to another, letting them push and

pull undrinkable, unusable salt water through.

The Hudson River, to the west, does use the term correctly—it is a legitimate freshwater

river—but by the time it arrives on the shores of Manhattan it doubles as another

ocean estuary.

As the tides rise, seawater pushes in against the flow.

The river only becomes usable freshwater somewhere between the Tappan Zee Bridge and Poughkeepsie,

depending on season and conditions.

That’s to say, the waterways that surround New York City, that make Manhattan and Staten

and Long the islands they are, are useless to quench the thirst of those living atop

them.

It’s a perpetual irony—this location, at the head of one of America’s greatest

navigable rivers, attracted more individuals and industry than any other in the country,

but that very location is the origin of its issues in supplying its populace with water. 

Strip away the skyscrapers of today, the brownstones of yesterday, and the streets of centuries

ago, and you have a lumpy, forested island with one major freshwater source.

Stretching across what are now four blocks in Chinatown and extending 60-feet or 18-meters

below the ground, it was called Collect Pond.

Some of the area’s earliest indigenous villages laid on its shores, and so did some of the

earliest European fortifications, but centuries on, after the Dutch left and the English moved

in, tanneries, breweries, and other water-hungry businesses took over these same lake-front

lots.

For the burgeoning city, this proved problematic as heavy use of the area’s sole major water

source made that same source unusable—the water was poisoned by the city around it,

and so were the people.

Wells were dug, but the situation was the same—the groundwater table beneath the grimy,

gritty streets was hardly fit for human consumption.

And beyond that, Manhattan was small, and so was its watershed—it was hardly sufficient

to supply the growing population, let alone the population of today.

New York City could no longer be self-sufficient.

It needed the help of the mainland. 

If one were to hop in a car near the old Collect Pond today, go north on FDR Drive, cross the

George Washington Bridge into New Jersey, bank north on Palisades Interstate Parkway,

north again on Interstate 87, and exit at Kingston, New York, they will have driven

for two to three hours, covered 100 miles, or 160 kilometers, and though far beyond city

limits, they’d find themself within the jurisdiction of a New York City police department—just

probably not the one you’ve heard of.

This is the Ashokan Reservoir, one of the most critical—and therefore, most closely-monitored—pieces

of New York City infrastructure.

Here, in an area that receives some forty inches of rainfall a year, is where the city

has stashed an impressive stockpile of water in a series of rather unimpressive looking

reservoirs. 

These six reservoirs have a staggering 460 billion gallon or 2 trillion liter storage

capacity and catch the drainage of some 1,600 square miles or 4,000 square kilometers of

Catskill mountain landscape.

And yet, while the size is extraordinary, and the adopted watershed’s nothing short

of essential to the city, it just doesn’t look like much.

In fact, what’s so spectacular about these reservoirs is how thoroughly mundane they

are.

There are no massive treatment facilities, no towering protective walls, nor any Hoover-dam-like

super structures—just a few large reservoirs surrounded mostly by forest, a few farms,

and some quiet upstate hamlets.

This is by design.

In fact, this simplicity is the system’s strength, and maintaining such simplicity

actually requires quite a lot of coordination. 

Of the billions of gallons that pass through this watershed, not one goes through a filter—making

the Delaware/Catskill system the largest unfiltered water supply in the US.

This distinction is a point of pride, but also the source of plenty of headaches.

In order to meet stringent national standards set by the EPA and the Clean Water Act, New

York City must monitor, protect, and prove over and over again the quality of this unfiltered

water.

Fortunately, the means for such heavy oversight were provided by the same 1905 state legislation

that green-lit the Catskill-Delaware project in the first place.

Along with the reservoirs, the New York legislature also established the New York City Department

of Environmental Protection to oversee city water, and gave the city the power to regulate

land use in the watershed so long as they provided local communities access to their

system.

Effectively, since 1905, New York City has had authority over what Catskill communities

did with their land and put in the water—hence the New York City police cars two hours away

from the city.

Today, to both ensure they meet quality standards and protect a logical terrorist target, the

DEP staffs a 200-officer police department that patrols the watershed by car, boat, and

even helicopter while maintaining a detective bureau and emergency service unit.

But it takes more than a few cops patrolling reservoir borders to ensure that the unfiltered

water is safe enough for millions.

For this, the DEP employs nearly 1,000 scientists, engineers, and additional staff in the watershed

to run daily tests in the reservoirs and their tributaries, and work with nearby farmers

and communities to limit dangerous pollutants making it into the runoff.

Everyday, robotic buoys spread across the reservoirs take measurements on the water’s

turbidity, while labs run test after test to measure the presence of waterborne pathogens.

While a tour of New York City’s adopted watershed makes it seem a quaint, pastoral

landscape, these waters and the woods around them are closely monitored, heavily guarded,

and teeming with DEP employees.

But that pristine, clean water is of little use sitting two hours north in the Catskills.

It has to actually get to the city.

Now, transporting one gallon of water 120 miles or 200 kilometers is no challenge.

What is is transporting the sheer quantity that 9 million people demand.

Every minute, the city consumes roughly an Olympic-sized swimming pool’s worth of water—680,000

gallons or 2,500,000 liters.

If one were to transport that quantity by semi-truck, it would take 71 of them—just

for a minute of consumption.

Of course, that’s not the solution.

What is are two of the longest and largest aqueducts anywhere on earth.

The first is called the Catskill Aqueduct—a winding miscellany of dams, tunnels, and siphons

capable of moving some half billion gallons of water a day 92 miles or 148 kilometers

to the south.

At the time of its opening, this aqueduct was heralded as a feat of engineering bested

only by marvels like the Panama and Suez canals.

It was something that superpowers would boast of, built by a single city.

But New York didn’t stop there—two decades on, it became clear that the ever-expanding

metropolis needed yet more supply.

So, it built one, single, continuous 85 mile, 137 kilometer tunnel.

This was an inconceivable step forward—before it, the world’s longest tunnel stretched

just 29 miles or 47 kilometers.

This was over three times longer, and still today, the better part of a century on, maintains

the title of the world’s longest. 

It enters the earth here—beneath the dam that holds back the waters of Rondout Reservoir—and

immediately plunges some 1,000 feet or 300 meters down—puzzlingly, beneath the elevation

of New York City.

You see, while most think of aqueducts as a network of canals, bridges, and tunnels

slanting slightly downward, modern aqueducts rarely take this form.

There are myriad insurmountable obstacles sitting between the Catskills and New York

City, so building a consistently downhill path with only a couple hundred feet of elevation

differential between the reservoirs and city would be an unbelievably complex endeavor

at this scale.

Conveniently, however, they didn’t have to.

The Delaware Aqueduct essentially operates like one giant inverted siphon.

Now, the physics behind how siphons work is not fully understood, there are competing

theories, but what matters is that liquid, sent through a tube, will always return to

its source elevation, regardless of the path of that tube.

That’s to say, water will flow upward, against the force of gravity, as long as the output

of the tube sits below the input.

Therefore, it’s rather useful that the Delaware Aqueduct’s origin, the Rondout Reservoir,

sits some 545 feet or 166 meters higher than its destination, the Hillview Reservoir.

The tunnel constantly changes elevation, avoiding obstacles, reaching its deepest point as it

passes through the bedrock below the Hudson River.

It then rises again to connect with the West Branch Reservoir, sinks, rises, and sinks

again before reaching its final destination, but thanks to the principles that make siphons

work, no outside forces are needed for the Catskill water to come out the other end—it’s

an entirely physics-driven transportation system. 

This aqueduct is incredibly efficient and effective, but also concerningly crucial.

Nearly half a century ago, officials identified a leak in the stretch of tunnel spanning beneath

the Hudson.

Spilling tens of millions of gallons per day, the gush of water flooded nearby communities

and, counterintuitively, contaminated their drinking water supplies.

Authorities have been mitigating and managing the issue ever since, even paying residents

to relocate away from the impacted area, but eventually, the problem had to be fixed.

Doing so required two decades of planning, one decade of construction, and more than

a billion dollars in bills.

A 2.5 mile, 4 kilometer diversion tunnel was built around the leakiest section, and in

late 2023, the Aqueduct will shut down for the first time in 65 years to accommodate

the five-to-eight-month process of connecting the new section to the old.

The shutdown is planned for winter, when water use tends to be lowest, but still, considerable

work has gone into assuring the Catskill Aqueduct can operate at full capacity, and that typically

minor water sources, like the Croton Aqueduct, can ramp up to pick up the slack.

With essentially two big pipes supplying nearly all of the water, the risk of failure in New

York’s water supply is uncharacteristically high for a city perpetually cognizant of the

worst case scenario, but it’s what’s necessary to move such a quantity such a distance from

where it falls to here: the Kensico Reservoir.

While sampling up until this point gives DEP staff a good idea as to what’s in the water,

this is the first point where they act on that knowledge and add to it.

This process begins at the exit tunnels of the Kensico Reservoir.

Here, chlorine is first added to kill off any lingering microorganisms.

Because chlorine levels dissipate over distance traveled, though, chlorine is again mixed

into the water at nearby Hillview Reservoir then, for water headed all the way to Staten

Island, again at the Richmond Chlorination Facility.

Along with chlorine, the DEP also adds fluoride to combat cavities, orthophosphate to limit

lead leakage from pipes, and sodium hydroxide to balance the water’s PH level.

Some additives are introduced to the system at static rates, while others are added in

accordance to real time water quality issues.

In 2005, for example, when upper watershed rainstorms led to increased turbidity, the

DEP added the chemical compound alum to the tainted supply as an emergency treatment to

lower particle level.

Beyond additives, the DEP further fortifies its water supply here, at the Catskill-Delaware

Ultraviolet Water Treatment Plant.

Capable of treating nearly 2.3 billion gallons a day, over twice the city’s daily demand,

this facility is the biggest of its kind in the world, with its 56 UV pipelines adding

another layer of defense against waterborne illnesses. 

But not all of New York’s water goes through this plant, nor does all of it emanate from

the pristine, protected Catskills.

The other 10% of New York’s water is still pulled from the Croton watershed, and unlike

its supply sibling, Croton water requires filtration.

Buried here below a golf course, air is added to Croton water to float particles and solids

to the surface for skimming before the same chemicals and minerals are added and the same

UV process is employed to turn what entered as raw water into a consumable product.

Effectively, the plant functions as a $3.2 billion one-stop-shop that buttresses the

Catskill/Delaware system by producing, at maximum capacity, up to 290 million gallons

of potable water a day.  

New York’s water supply is defined by billion dollar projects and multiple structures deemed

the longest or largest of their kind in the world, and yet, the most intricate, expensive,

and fickle stage may well be in final delivery. 

Once beyond Hillview reservoir, treated water that began its voyage months earlier and 100

miles away won’t see the light of day until it reaches a New Yorker’s tap.

Conveyed by tunnel, and pushed along by system pressure, it’s finally headed to a consumer. 

Three tunnels supply some nine million people with treated water.

More accurately, these tunnels get close enough to every neighborhood in every borough for

nearly 7,000 miles or 11,000 kilometers of water mainlines to connect these tunnels with

its nine million customers; filling the city’s iconic wooden water towers and pressurizing

the taps in its pizzerias. 

While these very tunnels and the mains that branch off them are what allowed New York

to bloom into a true megacity across the twentieth century, today they are old, leaky, and breaking

down.

Tunnel number 1 was activated in 1917, number 2 went online in 1936, and today both are

in need of inspection and likely repair.

As for the lines connected to the tunnels, while the DEP reported in 2020 that its mains

only experienced five breaks per 100 miles, a rate far below the national average of 25

per hundred, it still reportedly costs around $400 million a year to repair all the city’s

busted pipes; a process made infinitely more difficult by New York’s notoriously dense

underground infrastructure—power cables to subway lines.

Additionally, because of the age and varying quality of the pipelines supplying each city

block, the DEP has spread 965 water testing stations around the city where staff pull

samples each day and run over 34,000 tests each month.

Delivery expenses don’t end there either.

While operational, tunnel number 3 is still years away from completion even though the

project broke ground in 1970.

Sitting 600 feet or 180 meters below ground, and running 60 miles or 100 kilometers long,

the tunnel’s been called one of the most complex public works ever attempted and will

be the city’s single largest capital project, costing around $6 billion and scheduled for

completion in 2026. 

New York is revered for its water: locals boast about it constantly, and even claim

it's the key factor behind the city’s purportedly exceptional pizza and bagels.

But the defining factor of the system behind it is simplicity.

It lets nature do the work of gathering and purifying, then uses just two tunnels and

physics to transport it to the city.

Counterintuitively, however, this level of simplicity is unbelievably expensive.

Smaller, cash-strapped cities have not historically had the funds to design elaborate programs

to protect their watersheds and build massive networks of record-setting aqueducts, leaving

them with more marginal sources that today require more complex systems to make potable.

But beyond the money, New York City had foresight—the ability to recognize that future stability,

growth, and success all revolved around the task, simultaneously simple and complex, of

getting good water.

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