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Groundwater System for 2005

Groundwater Distribution AreasHistorically, the Jamaica Water Supply Company (JWS), a privately owned water supply company, operated a group of wells that served the communities of southeast Queens and a part of Nassau County.  In 1996, New York City purchased the portion of the JWS contained within the borough of Queens and took responsibility for the delivery of drinking water to the community.  After acquiring the JWS wells DEP renamed the group of wells the Groundwater System.

Comprised of 69 wells, the Groundwater System provides drinking water to less than 100,000 people in New York City.  Residents within the system receive groundwater or a mix of ground and surface waters depending on the water demand and the available supply.  In 2005, the Groundwater System (PWSID NY7011735) supplied an average of 2.2 million gallons per day (mgd) of drinking water from 5 wells, less than 1% of the City’s total usage.

Located in southeastern Queens, the Groundwater System covers an area of approximately 5.5 square miles.  The neighborhoods serviced by the 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 2005

The table below lists the wells that were in operation in 2005:

Well # Town Aquifer Depth (ft.) Present Well Capacity (mgd)
5 Hollis Magothy or Cretaceous Formation 275 1.73
23A Cambria Heights Magothy or Cretaceous Formation 362 2.30
32 South Ozone Park Glacial or Post Jameco Formation 105 1.30
43A Richmond Hill Magothy or Cretaceous Formation 242 0.58
50A Fresh Meadows Magothy or Cretaceous Formation 254 1.44

For a more extensive listing encompassing all the wells within the Groundwater System, with location, aquifer, depth and operational information, see:

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Geology

An aquifer is a natural underground layer of porous, water-bearing materials (sand, gravel) usually capable of yielding a large amount or supply of water. Three aquifers run the length of geographic Long Island, which includes Brooklyn and Queens counties. The three are 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. 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 operate at several wells to remove volatile organic compounds (VOCs).

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Operational Information - 2005

In the Groundwater System, Wells 5, 23A, 32, 43A and 50A were online in 2005. Wells 5, 23A and 50A were all operated remotely via telemetering from Station 6, which is the headquarters for Groundwater Operations, located in Jamaica, Queens. These three wells were started and stopped on a daily basis depending upon distribution demands. In general, the wells were started everyday between 5AM and 6 AM (as people start to wake up) and shut down when the system demand was met. They were then restarted around 3 PM as system demand increased (kids coming home from school) and shutdown again later in the evening (after 10PM when dishwashing and bathing are over). The remaining two wells, Wells 32 and 43A, were operated on site and normally ran 24 hours a day.

Individual Well Information:

Well 5: Originally put into service in 1924, Well 5 was designed for a flow rate of 1200 gallons per minute (gpm). The water is pumped from the wellhead, or water source, through an air stripping plant in order to remove any volatile organic compounds (VOCs) from the water before it is discharged into the distribution system. Well 5 remained in service for the entire 2005 calendar year.

Well 23A: Originally put into service in 1933, Well 23A was designed for a flow rate of 1200 gpm. The water is pumped from the wellhead into a one million gallon storage tank before it is discharged into the distribution system. Well 23A was taken out of service in January 2005 for pump replacement and has not returned to service due to water quality concerns.

Well 32: Originally put into service in 1952, Well 32 was designed for a flow rate of 1194 gpm. The water is pumped from the wellhead directly into the distribution system. Well 32 was taken out of service in January 2005 due to water quality concerns, and remained out of service for the duration of 2005.

Well 43A: Originally put into service in 1960, Well 43A was designed for a flow rate of 1200 gpm. As with Well 32, the water is pumped from the wellhead directly into the distribution system. Well 43A was put into service in April 2005, but was taken out of service for pipe and treatment upgrades in September 2005. Well 43A remained out of service for the duration of 2005.

Well 50A: Originally put into service in 1962, Well 50A was designed for a flow rate of 1000 gpm. The water is pumped from the wellhead through an air stripping plant to remove the VOCs before being discharged into the distribution system. Well 50A was taken out of service in July 2005 due to a blower malfunction and remained out of service for the duration of 2005.

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Water Quality Data

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
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Definitions

GAC – granular activated carbon, a form of particulate carbon manufactured with increased surface area per unit mass to enhance the adsorption of soluble contaminants

gpm – Gallons per minute

mgd – Million gallons per day

MTBE - Methyl Tertiary-Butyl Ether, formerly an additive to gasoline

VOCs – volatile organic compounds, a class of organic compounds that includes volatile liquids

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Reservoir Levels

Current: 66.3%

Normal: 78.6%