Drinking Water in NYC

Source of New York City’s Drinking Water
New York City’s water supply system services more than 1 billion gallons of fresh water daily to 9 million customers throughout the five boroughs and upstate. New York City consists of 19 reservoirs, 3 controlled lakes, and over than 6,000 miles of pipes, aqueducts, and tunnels. Due to the City’s ongoing efforts to maintain the appropriate volume and high quality of water in the distribution system, there is some rotation in the water sources used by DEP. In 2008, 98.3% of our water came from the Catskill/Delaware System, located in Delaware, Greene, Schoharie, Sullivan, and Ulster counties, west of the Hudson River. The Croton System, the City’s original upstate supply, provided, on average, 1.6% of the daily supply to the City from 12 reservoir basins in Putnam, Westchester, and Dutchess counties. New York City’s Groundwater System in southeastern Queens was off-line for the entire 2008 calendar year.

Another way to recycle water is through Desalination. Desalination refers to any of several processes that remove excess salt and other minerals from water. More generally, desalination may also refer to the removal of salts and minerals. In the context of New York City, it may provide a way New Yorkers to have access to fresh drinking water without relying on other sources. Daylighting buried streams may also increase access to fresh water.

Map of New York's Water Supply

Regulation of Drinking Water
As water travels over the surface of the land or through the ground, it dissolves naturally-occurring minerals and, sometimes, radioactive material and can pick up substances resulting from the presence of animals or from human activities. In order to ensure that tap water is safe to drink, the New York State Department of Health (NYSDOH) and EPA prescribe regulations that limit the amount of certain contaminants in water provided by public water systems. The State Health Department’s and the federal Food and Drug Administration’s (FDA) regulations establish limits for contaminants in bottled water which must provide the same protection for public health.

Ensuring Safe Water
The Safe Drinking Water Act (SDWA) Amendments of 1996 required states to develop and implement Source Water Assessment Programs (SWAP) to: identify the areas that supply public tap water; inventory contaminants, and assess water system susceptibility to contamination; and inform the public of the results.

Starting in 1993, and culminating in 1997 with the historic watershed agreement and Filtration Avoidance Determination (FAD), New York City began implementation of a series of programs to reduce the susceptibility of the surface water supply to contamination from a variety of sources. These programs, which are still ongoing, operate under the close scrutiny of both the NYSDOH and the EPA. Due to these efforts, further detailed below, the SWAP methodologies applied to the rest of the state were not applied to the New York City water supply by NYSDOH.

Drinking Water Monitoring
DEP monitors the water in the distribution system, the upstate reservoirs and feeder streams, and the wells that are the sources for the City’s supply. Certain water quality parameters are monitored continuously as the water enters the distribution system, and water quality is regularly tested at sampling points throughout the entire City. DEP conducts analyses for a broad spectrum of microbiological, chemical, and physical measures of quality. DEP conducts most of its distribution water quality monitoring at approximately 1,000 fixed sampling stations throughout the City.

DEP is required to monitor drinking water for various parameters on a regular basis. Results of regular monitoring are an indicator of whether or not drinking water meets health standards. DEP collects samples at a frequency prescribed by the State. In 2008, DEP met all State and federal sampling requirements.

Lead in Drinking Water
New York City water is virtually lead-free when it is delivered from the City’s upstate reservoir system, but water can absorb lead from solder, fixtures, and pipes found in the plumbing of some buildings or homes. Under the federal Lead and Copper Rule (LCR), mandated at-the-tap lead monitoring is conducted at selected households located throughout the City. Based on the results of this monitoring, in 2008, the 90th percentile did not exceed 15 µg/L, the established standard or Action Level (AL) for lead. DEP offers a Free Residential Lead Testing Program which allows all New York City residents to have their tap water tested at no cost. The Free Residential Testing Program is the largest of its kind in the Nation: Over 75,000 sample collection kits have been distributed since the start of the program in 1992.

Table of Contents:


o CSO in NYC
Combined Sewer System
Eliminating CSO

o Drinking Water in NYC
Buried Streams

o Holland

o Water Around the World

o PLANYC Initiatives

Leave a Reply