Every New Yorker has heard the phrase: “there is something in the water.” This mystical quality, the theory goes, is the secret ingredient behind the city’s legendary pizza crusts and chewy bagels. New York’s water provides the flavor, texture, and soul of its sought-after bread. Behind the seamlessness of the city’s treasured water flowing straight from the tap lies a variety of standards and regulations that assure this drinking water is tested and free from contaminants—ultimately safe for your consumption.
How New York City Secured Its World-Famous Drinking Water Supply
In the late 1800s, as New York City (NYC’s) population grew, safe drinking water became scarcer. Consequently, concerns about a long-term water crisis were brewing. To combat these concerns to a potential water crisis, city officials decided to create reservoirs in the Catskill Mountains—where there was abundant clean water. What followed was one of the most ambitious water engineering projects in U.S. history.
Today, the NYC water supply system reliably delivers more than 1.1 billion gallons of safe drinking water daily to 9 million people—representing nearly half the population of all New York State. Celebrated for its taste, purity, and consistency, New York City’s tap water is not just a local asset—it’s a global benchmark for urban water supply systems.
Why Is NYC’s Tap Water Considered Excellent?
New York City tap water is often considered among the best in the U.S.—and sometimes even the best in the world—for several key reasons:
Pristine Source: The Catskill/Delaware Watersheds
90% of NYC’s water comes from the Catskill and Delaware watersheds, located up to 125 miles north of the city. These watersheds are protected, forested areas with minimal development, meaning cleaner, naturally filtered water right from the source.
Unfiltered But Ultra-Regulated
NYC is one of the few major U.S. cities with a filtration waiver from the Environmental Protection Agency (EPA). This means the water is so clean at the source that it does not need a full filtration system. Instead, it is treated with:
- Chlorine (to kill bacteria)
- UV light (to kill protozoa like Giardia)
- Orthophosphate (to prevent lead from pipes leaching into the water)
- Sodium hydroxide (to control acidity and corrosion)
Extensive Testing
NYC conducts over 1,000 daily tests for water and monitors more than 250 variables. Water is tested at every stage: source, distribution, and point-of-use. The Department of Environment Protection (DEP) performs more than 500,000 tests each year to monitor water quality.
Gravity-Powered Distribution
Water flows from the upstate watersheds—the Delaware, the Catskill, and Croton—to the city by gravity through aqueducts, making it energy-efficient and reducing the risk of contamination from mechanical pumping.
Taste and Softness: NYC’s Water Is Soft
NYC’s water is soft, meaning it has low levels of calcium and magnesium, making the water better for dough making. This not only tastes smoother, but it is also prized by bagel and pizza makers (it affects dough texture) as well as beer and coffee shops (soft water brews better). Even in the kitchens of the city’s bustling ramen joints, there are even hushed suggestions that the water is just as vital to the broth as the prized pork bones themselves.
Who Regulates NYC Drinking Water?
NYC drinking water is regulated by a combination of city, state, and federal agencies. Here is a breakdown of who oversees it:
- New York State Department of Health (NYSDOH) sets the maximum contaminant levels (MCLs) for various contaminants, including PFAS, in New York’s drinking water systems.
- The U.S. Environmental Protection Agency (EPA) prescribes federal regulations and sets national maximum contaminant levels (MCLs).
- NYC Department of Environmental Protection (DEP) is responsible for monitoring and ensuring the safety of the city’s tap water.
How NSF/ANSI Standards Help Protect NYC Drinking Water from Harmful Contaminants
NSF/ANSI drinking water standards assure that chemical contaminants and impurities imparted from products, components, and materials do not leach harmful chemicals into the water. These American National Standards relate to NYC drinking water as a health-effects benchmark for water system components and products. For example, NYC requires that storage tanks coming into contact with its drinking water supply meet NSF/ANSI and other applicable national standards developed by ANSI-accredited organizations.
While NYC mandates the use of materials compliant with NSF/ANSI standards for its infrastructure, the standards themselves are voluntary guidelines developed by a third party, not enforceable regulations. The city’s drinking water is ultimately regulated and monitored by other agencies.
Examples of NSF/ANSI Standards that Protect Your Drinking Water
NSF/ANSI 61 sets health effects criteria for water system components, which are materials and products (like pipes, coatings, and gaskets) that come into contact with drinking water, ensuring they do not leach contaminants into the water supply.
- You can learn more about NSF/ANSI 61 in our blog post: NSF/ANSI 61-2024: Drinking Water System Components – Health Effects.
NSF/ANSI 600 defines how to assess the toxicity of substances that may contaminate drinking water. It aims to establish the human health risk, if any, of the substances imparted to drinking water under the anticipated use conditions of the product.
- You can more about the NSF/ANSI/CAN 600 in our blog post: NSF/ANSI/CAN 600-2024: Chemicals in Drinking Water.
NSF/ANSI 60 establishes minimum health effects requirements for chemicals, chemical contaminants, and impurities added directly to drinking water from treatment chemicals. It covers coagulation and flocculation, softening, precipitation, sequestering, pH adjustment, corrosion/scale, and disinfection and oxidation chemicals, as well as miscellaneous treatment and water supply chemicals.
- You can learn more about NSF/ANSI 60 in our blog post NSF/ANSI 60-2024: Drinking Water Chemicals Health Effects.
NSF/ANSI 42 establishes minimum requirements for materials, design and construction, and performance of drinking water systems dealing with aesthetic (nonhealth) effects contaminants in water supplies.
- You can learn more about NSF/ANSI 42 in our blog post: NSF/ANSI 42-2023: Drinking Water Treatment Units, Aesthetic Effects.
NSF/ANSI 58 specifies requirements for materials, design and construction, and performance of RO drinking water treatment systems.
- You can learn more about NSF/ANSI 58 in our blog post: NSF/ANSI 58-2022: Reverse Osmosis for Drinking Water.