NYC Sewage Treatment Plant Update #3

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Riverkeeper and our science partners from Lamont Doherty and Queens College sampled the affected area from the Tappan Zee Bridge to the Battery again on Monday, 7/25. We used the same grid sampling pattern that was used previously to determine the sewage impacts on the Manhattan shoreline as well as mid-channel and on the New Jersey side of the River.

See our prior spill reports posted on: 7/21/11 and 7/25/11

On Monday, 7/25, Enterococcus counts had diminished from previously high levels as the North River Sewage Treatment Plant had come back on-line, although there were still several unacceptable locations along the Manhattan shoreline. Entero counts were only moderately above acceptable EPA guidelines for swimming. Based on our sampling, it appeared that the plant was discharging water that was not contaminated with fecal indicator bacteria. Thank you to everyone that worked hard to get the plant back on-line.

Download data for our three day survey from the TZ Bridge to the Battery (PDF)

It’s interesting to note that when we sampled at the North River Plant, the water in the immediate vicinity looked visibly contaminated, yet there was a very low count (10). Meanwhile, the water at Dyckman Street Beach and at the 125th Street Pier looked fairly normal, yet their Entero counts were unacceptable (110 and 173). This goes to show that one cannot tell microbial water quality by simply looking at it. You have to do water quality testing to truly understand the safety of the water. There is no substitute for data collection and responsible action based on the data.

Still, this accident should be viewed in the appropriate context. It is important to note that Entero counts at the mouth of the Saw Mill River in Yonkers, were about as high on the July 25th as many of our samples taken in Manhattan immediately after the North River Plant shutdown. This was most likely due to sewage overflows caused by the significant rainfall that took place the afternoon and night before our sampling on the 25th. Our prior data from this site finds this location to be frequently exposed to high levels of sewage contamination. Despite this known fact, there are no warnings given to the people of Yonkers and lower Westchester about this chronic and significant contamination along the shoreline.

Download data for our May 2011 patrol from the TZ Bridge to the Battery (PDF)

Chronic wet weather sewage discharges are a huge problem throughout the entire 155 mile Hudson River Estuary. This point is echoed when our data from the spill is compared to that of our May 2011 sampling patrol. Throughout May there was significant rainfall, causing many of our sampling locations to be contaminated. Sewage contamination does not only result from accidents at sewage treatment plants. It happens on a regular basis each time there is significant rainfall. This contamination from wet weather discharges can cause large portions of the river to have unacceptable conditions like those we encountered west of Manhattan last week.

It is imperative that each time there is sewage contamination in the River, whether from infrastructure failure (e.g. a burst pipe or fire in a treatment plant) or the more frequent wet weather discharges, the proper authorities must alert the public of potential risk. It is inexcusable for individuals to be swimming in sewage, yet it happens frequently due to the lack of proper monitoring, notification, and enforcement. There were large differences in monitoring data collected by Riverkeeper and the NYC-DEP in response to the recent spill. The NYC-DEP data, collected only in mid-channel portions of the river, showed a maximum Entero count of 400 cells/100ml, whereas the Riverkeeper data including near shore sites had a maximum of 104,620 cells/100ml. This makes it clear that monitoring activities must include near shore sites, where the public is most likely to come into contact with the water.

Video: Riverkeeper’s Rob Friedman tell the story of his experiences following the massive sewage spill.