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Riverkeeper Releases First Comprehensive Study of Sewage Contamination in Hudson Estuary


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Contact Tina Posterli, [email protected], 914-478-4501 x239

Water quality varies widely: 21% of samples failed guidelines for safe swimming

Ossining, NY, August 9, 2011– Riverkeeper released a report on sewage contamination in the Hudson River today that reveals sewage contamination from New York Harbor to above the Troy dam.

“Our findings show that while water quality in the Hudson has greatly improved in recent years we still have a significant problem with sewage contamination,” said John Lipscomb, Riverkeeper Boat Captain. “The recent 200+ million gallon sewage spill in New York City is only a minor part of widespread contamination that regularly occurs in the Hudson.”


  • While average water quality in the Hudson Estuary passed the U.S. EPA guideline for safe swimming the majority of the times Riverkeeper sampled, it failed the equivalent of 1½ days a week on average (21% of samples).
  • By comparison, water quality samples collected at beaches nationwide failed the EPA guideline for safe swimming 7% of the times sampled over the same time period, 2006–2010 (including ocean, bay and Great Lake beaches).
  • Of the ten counties on the estuary, only four test for sewage contamination along their shorelines, and that testing is limited in scope and frequency. No counties report their findings to the public.
  • NYC DEP does test water quality in New York Harbor and publishes findings a year or two later.
  • DEP data is averaged seasonally which means that episodes of extreme contamination caused by rain events are not reported to the public.
  • Despite this lack of critical data, the Department of Environmental Conservation (DEC) has classified Hudson River waters from north of the Bronx Borough line all the way to the northern end of Columbia County as acceptable for swimming.
  • During and after rainfall sewage contamination increases in all the regions and at all the types of sites where we sample, but not at every individual location.
  • Overall the percent of samples that were unacceptable increased from 9% in dry weather to 32% in wet weather–a threefold increase. It is not known how long sewage contamination persists after a wet weather release¬–how many sunny days it will take to restore water quality.
  • Contamination is highest near the shoreline and at tributaries, which show unacceptable samples 24% and 34% of the time respectively.
  • Mid-channel sites had the lowest contamination level at 16% unacceptable.
  • In many cases contamination is local and community specific¬–a scale that lends itself to local solutions.

“The Hudson River has undergone a renaissance as a destination for recreation, tourism and water sports,” said Paul Gallay, President and Hudson Riverkeeper. “It is an essential contributor to our area’s economy. In order to protect this resource, and the millions of people who enjoy it, we need to test for sewage contamination, alert the public when we find it and work to eliminate its sources.”

To improve Hudson River water quality and protect the health of New Yorkers who enjoy contact with the Hudson and its tributaries, Riverkeeper is calling for the following actions:

  • Hudson River counties need to conduct weekly water quality testing at all user areas and develop predictive modeling to forecast water quality to protect public health.
  • New York State must adopt a “single sample” standard for evaluating water quality in order to better reflect the spikes in contamination found in the estuary.
  • New York State must pass a Sewage Right to Know Law that requires timely public notification of sewage contamination in our waterways, both accidental and chronic.
  • Local and state governments must locate contamination sources and prevent sewage from entering the river and its tributaries by investing in wastewater infrastructure.
  • Citizens and communities need to identify and solve their local contamination problems by supporting infrastructure upgrades, green infrastructure projects, improved septic field regulations and maintenance, and water conservation.

The report is based on the first estuary-wide, multi-year study of sewage contamination in the Hudson that posts water quality data to the public. Since the summer of 2006, Riverkeeper and science partners Columbia University, Lamont-Doherty Earth Observatory and Queens College, CUNY, have taken over 2000 samples at 75 fixed locations. All 75 locations in the study showed signs of sewage contamination at some time during the study period.

In the summer, the Hudson River Estuary serves as a 155-mile long beach for countless New Yorkers. Water quality has improved dramatically since the passage of the Clean Water Act in 1972, however many communities still suffer episodes of high, often very localized, contamination.

The report compares findings from four distinct Hudson Valley regions and explains the many different sources of sewage contamination–from huge combined sewer systems in New York City and Albany, to infrastructure failures in Westchester and Rockland Counties, to contaminated water flowing from several major tributaries into the mid Hudson region.

You can view the full report online and see Riverkeeper’s online Water Quality Database and Monthly Water Quality Reports for more information.

Riverkeeper is a member-supported, watchdog organization dedicated to defending the Hudson River and its tributaries and protecting the drinking water supply of nine million New York City and Hudson Valley residents. For more information, please visit

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