Threats to NYC’s Tap Water

Because NYC’s water supply is unfiltered, an aggressive program of watershed protection is essential to protect it at its source. The continued quality of the city’s premier drinking water depends on ensuring that the watersheds remain unpolluted and that the water infrastructure is sound. The greatest threats to the NYC watershed are sprawl, aging infrastructure and the presence of pharmaceuticals in our waters.

• Sprawl-style Development

  Sprawl is haphazard development characterized by strip malls outside of existing downtown centers and McMansion subdivisions in formally rural areas. This low density development is dependent on cars and requires new infrastructure and services to be delivered to these dispersed locations. Sprawl creates a preponderance of impervious surfaces — roads, parking lots, building footprints — which devour open space and curtail the landscape’s ability to purify stormwater naturally. Rain collects on impervious surfaces, scours pollutants off roads, and runs off into the nearest surface waters, impacting our drinking water supply.
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• Industrial Gas Drilling

  The entire West-of-Hudson portion of the New York City Watershed (supplying 90% of drinking water to over half the state’s population) sits on top of part of the Marcellus Shale, a large mineral reserve deposit deep beneath the earth’s surface. Oil and gas companies have known about this shale reserve for decades, but the technology to extract natural gas from it has become available only recently. The Marcellus Shale spans across at least five states. To extract natural gas from the mineral reserve, oil companies plan to use a process called “hydraulic fracturing.”

  Fracturing involves injecting toxic chemicals, sand, and millions of gallons of water under high pressure directly into shale formations. This toxic brew, along with any natural gas, is then extracted, or leaked to the surface. Whether any toxic discharges will flow into New York City’s drinking water supply is uncertain.

  Riverkeeper has led the charge for industrial gas drilling using high-volume hydraulic fracturing to be banned within the NYC Watershed and all other sensitive water supply areas.
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• Aging Infrastructure

  The delivery of New York City’s first-rate water depends on a remarkable 6,000-mile network of pipes, shafts and subterranean aqueducts that carries an average 1.5 billion gallons of pristine water each day from 19 upstate reservoirs to over 9 million New Yorkers. The mostly gravity-fed city water delivery system is a remarkable engineering achievement and the single largest man-made financial asset in New York State. Four decades ago, the city’s water supply was regarded as one of America’s proudest engineering accomplishments. But the city’s water infrastructure is now in a state of disrepair that threatens its ability to continue to supply the city with water.

  The New Croton Aqueduct stretches 31 miles from the New Croton Reservoir in Westchester County to the Jerome Park Reservoir in the Bronx and the 135th Street Gatehouse in Manhattan. Over 100 years old, its tunnels and shafts are in serious need of rehabilitation.

  Constructed between 1937 and 1945, the Delaware Aqueduct draws from four reservoirs – the Cannonsville, Pepacton, Neversink and Rondout – to provide between 50 and 80 percent of the city’s daily water demand. The 85-mile long Delaware Aqueduct is the world’s longest tunnel. The Rondout-West Branch Tunnel of the aqueduct, located at Wawarsing and Roseton, has been leaking about 35 million gallons of water a day for almost 20 years.

  The level of federal funding for clean water infrastructure has dropped from 78 percent in 1978 to 3 percent in 2007. If New York City cannot continue to successfully protect the source of 90% of its water supply—the Catskill/Delaware system—it may be forced to build a water filtration plant estimated to cost $8-12 billion for construction with operating costs of $350 million a year.
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• NYC Must Invest Now to Save in the Long RunFunding Shortfalls

  In the interest of protecting human health and preserving freshwater ecosystems, filtration of public drinking water supplies should be considered as a last resort to be employed only when an unfiltered water supply poses an imminent threat to public health. Sound watershed protection programs not only safeguard human health and aquatic life but also are vastly more economical than filtration.

  If New York City fails to demonstrate that it can continue to successfully protect the source of 90% of its water supply, the Catskill/Delaware system, then EPA will likely order the City to build a filtration plant. And the price is steep: the cost of filtration for the Catskill/Delaware water supply is estimated at $8-12 billion for construction with operating costs around $350 million a year ($1 million a day!). The practical consequences of that decision will be that water rates will rise even higher, and badly needed funds will be drained from essential City services such as police, infrastructure, health care, education, and transportation. And, worst of all, if a filtration plant is ever built, the City’s watershed protection efforts will most likely fall by the wayside.

  As part of the Clean Drinking Water Coalition, Riverkeeper advocates for full funding of the watershed protection programs – such as the City Department of Environmental Protection (DEP) Police Force, and land acquisition – that are necessary to fully protect source waters throughout the NYC Watershed.

• Turbidity

  Turbidity refers to the cloudiness of water caused by suspended sediment and other solid particles. When stormwater runoff erodes clay soils and transports sediment to surface waters, attached to the sediment are nutrients such as phosphorus and other contaminants such as oil and grease. When these pollutants enter streams, lakes and conceal the presence of pathogens such as Giardia and Cryptosporidium, making detection difficult and increasing the risk of waterborne disease outbreaks.

  To reduce turbidity, operators of public drinking water supply systems must remove suspended sediment and other particles before the water reaches the distribution system. In the New York City water supply system, the Department of Environmental Protection (DEP) treats turbid water in the aqueducts with aluminum sulfate, commonly referred to as alum, which attaches to suspended particles and settles to the bottom of the aqueduct’s effluent chambers. The clear water then passes into a reservoir of the distribution system and the remaining sludge must be removed and disposed of.

  Although alum is effective in reducing turbidity, its use relies on ‘end-of-pipe’ solutions rather than upstream source controls. Sound watershed management, such as stream restoration and stormwater management practices, can reduce and control turbidity before it reaches the aqueducts. Reducing the need to apply alum also reduces the impacts of alum sludge on the ecology of receiving reservoirs and the impacts to aquatic life associated with dissolved aluminum, which is toxic to fish and other species.

• Pharmaceuticals

  In 2006, the New York State Department of Health reported that organic wastewater contaminants in U.S. streams included 11 sampling sites in the Croton watershed. All 11 sampled streams contained detectable levels of human pharmaceutical compounds. In March 2008, the Associated Press published a series of reports documenting the results of its investigation that detected the presence of pharmaceuticals in the drinking water supplies of 24 of 28 U.S. metropolitan areas – including the New York City supply. In response to the AP reports, the New York City Council held public hearings on this issue on April 3, 2008. Riverkeeper helped prepare testimony that was presented by NYPIRG on behalf of the Clean Drinking Water Coalition (CDWC).

  Pharmaceuticals and veterinary medicines are excreted or improperly discarded, and enter the waters mostly through residential sewage or farm runoff. Though waters are processed at wastewater treatment plants, pharmaceuticals can often pass through. While detectible levels of pharmaceuticals in the NYC drinking water are quite low, cumulative impacts of consumption over time are not well documented.

  The New York City Department of Environmental Protection, which oversees NYC’s water system, has not tested the drinking water for pharmaceuticals, despite these findings in its watershed.

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