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Groundwater System for 2008

Between 1887 and 1996, the privately owned Jamaica Water Supply Company (JWS) operated a group of wells that served the communities of southeastern Queens and portions of Nassau County.  In 1996, New York City purchased the Queens portion of the JWS and took responsibility for the delivery of drinking water to those communities served by the groundwater wells.  After acquiring the JWS wells, the Department of Environmental Protection (DEP) renamed the group of wells “the Groundwater System.”

Comprised of 69 wells, the Groundwater System provides drinking water to fewer than 100,000 people in New York City.  Residents within the system receive groundwater or a mix of ground and surface waters depending on demand and supply availability.  However, in 2008, none of the wells in New York City’s Groundwater System (PWSID NY7011735) were operational.

Located in southeastern Queens, the Groundwater System covers an area of approximately 5.5 square miles.  The neighborhoods connected to the Groundwater System include: Cambria Heights, Hollis, Holliswood, Jamaica, Kew Gardens, Queens Village, Richmond Hill, St. Albans, South Jamaica, and South Ozone Park.

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Wells in Operation in 2008

There were no wells in operation in 2008:

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An aquifer is a natural underground layer of porous, water-bearing materials (sand, gravel) usually capable of yielding a large supply of water. Three aquifers run the length of Long Island, which includes Brooklyn and Queens Counties: the Upper Glacial, which is the shallowest; the Magothy, which is the middle layer; and the Lloyd, which is the deepest. Formed approximately 60 million years ago, the three aquifers are separated by layers of clay.

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Treatment Information

All groundwater entering New York City’s distribution system is treated with chlorine, fluoride, food grade phosphoric acid, and, in some cases, sodium hydroxide. New York City uses chlorine to meet the New York State Sanitary Code and federal Safe Drinking Water Act disinfection requirements. Fluoride, at a concentration of one part per million, is added to help prevent tooth decay and has been added since 1966 in accordance with the New York City Health Code. Phosphoric acid is added to create a protective film on pipes that reduces the release of metals such as lead and copper from household plumbing. Additionally, a sequestering phosphate is applied at several wells to prevent the precipitation of naturally occurring minerals, mostly iron and manganese, in the distribution mains and customers’ household piping. Air stripper facilities can be operated at several wells to remove volatile organic compounds (VOCs).

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Operational Information - 2008

The 69 wells which comprise the Groundwater System were not used for drinking water distribution in 2008. These wells are either mechanically inactive, for emergency use only, or have poor water quality. This information is available on the Service Status Table.

Individual Well Information:

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Water Quality Data

Index Numbers

DEP assigns index numbers to sampling locations throughout the distribution system. The nomenclature of the index for a well sample location signifies the status of the water at a specific tap. An index number followed by the letters E, F or T denotes sampling sites that are treated, or finished groundwater. Well index numbers that have no letter after the number, or are followed only by the letters A, B, C, D, I or S are considered untreated, or raw water. Examples of untreated water IDs are W5 and W23A.  Examples of treated water are W5E and W23AT. The following table illustrates this in greater detail:

Index Numbers  Description 
W##, W##A-D, I, S Groundwater wells sampling points prior to final treatment
W##E Effluent finished groundwater from wells with air-stripping
W##F Finished groundwater effluent from wells without any special treatment
W##T Treated finished groundwater effluent from sequestering/iron treatment wells

Data Tables and Graphs

There were no wells in operation in 2008; therefore there are no 2008 Groundwater Supplemental data available.  Previous years’ data are available at the links provided below.

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Previous Years

Reservoir Levels

Current: %

Normal: %