Where Does Tri-State Area Water Come From?
New York City operates one of the largest and most complex municipal water systems in the world. NYC's water comes primarily from two unfiltered surface water systems: the Catskill/Delaware System and the Croton System, supplying approximately 1.1 billion gallons per day to over 9 million people. New York State has granted filtration avoidance for the Catskill/Delaware system — meaning the water is treated only with UV disinfection and chlorination, not filtered through conventional physical media. This is notable because it preserves natural mineral content but also means biological and chemical contaminants are addressed primarily through chemical disinfection.
New Jersey's water comes from a more diverse mix of sources — surface water from reservoirs including the Wanaque, Boonton, Oradell, and Round Valley Reservoirs, as well as from the Delaware and Raritan Canal system, and groundwater from the Coastal Plain and Highlands aquifers. Many NJ municipalities rely on the Delaware River as a source, which receives agricultural, industrial, and urban runoff across its 13,500-square-mile watershed.
Key Contaminants in NY and NJ Water
Lead: While New York City's source water is very low in lead, the aging infrastructure in many buildings introduces lead at the tap. NYC has over 360,000 lead service lines and in-building lead pipes. The EPA Lead and Copper Rule requires testing at the tap, not the source — and tap testing in older buildings frequently reveals lead levels well above the EPA action level of 15 ppb. NJ has similarly aging infrastructure challenges, particularly in older cities like Newark, where lead pipe replacement is still ongoing following documented contamination incidents.
Disinfection Byproducts (DBPs): New York City uses chloramine (a combination of chlorine and ammonia) as its secondary disinfectant. Chloramination creates a different set of disinfection byproducts than plain chlorination, including NDMA (N-nitrosodimethylamine), a probable human carcinogen. NYC's annual water quality reports have detected NDMA and other nitroso compounds at low but measurable levels. New Jersey surface water systems report haloacetic acid (HAA) and trihalomethane (THM) levels that frequently approach or exceed regulatory limits.
PFAS (Per- and Polyfluoroalkyl Substances): The EWG's National Tap Water Database has identified PFAS compounds in multiple NJ water systems, particularly those serving areas near industrial sites in Gloucester, Camden, and Burlington counties. New Jersey was among the first states to set PFAS maximum contaminant levels — 14 ppt for PFOA and 13 ppt for PFOS — stricter than the current federal standard.
Chlorine and Taste: Many Tri-State residents on municipal water notice a strong chlorine taste and odor, particularly in late summer when warmer source water temperatures require higher disinfectant doses. While chlorine is safe at regulated levels, it is easily removed by carbon filtration and is the most common motivation for in-home water treatment.
The Special Challenge of Aging Infrastructure
The Tri-State area's water infrastructure was largely built in the mid-20th century and is due for extensive replacement. Lead service lines, aging cast iron distribution mains, and in-building galvanized steel and lead pipes remain common in pre-1987 construction. Even if source water is lead-free, water passing through lead or copper with lead solder can dissolve measurable concentrations of these metals before reaching the tap — a phenomenon dependent on water chemistry, pipe age, and standing time.
For households in buildings constructed before 1987 (when lead solder was banned), testing specifically for lead at the tap — not just relying on annual utility reports — is strongly advisable.
What Home Filtration Can Address
For Tri-State residents, the most relevant home treatment priorities are: lead removal (via NSF/ANSI 53-certified filters or RO), PFAS reduction (RO or high-contact-time activated carbon), chlorine/chloramine taste and odor (carbon filtration), and general TDS reduction for improved water palatability (RO). A free water test identifies which contaminants are actually present in your home's water at the tap and guides appropriate system selection.