check out the latest


Intro to New York Harbor Part 2: After the Clean Water Act

By Heather Flanagan
March 7, 2017

New York Harbor’s water is cleaner than it was 100 years ago and its biodiversity is on the rise thanks to laws like the Clean Water Act and the tireless work of water protectors- and you can be a part of it!



Signs from 1973 (top) and 2016 (bottom) showcase clean water projects designed to improve health of Jamaica Bay through improvements to the 26th Ward Water Pollution Control Plant, jointly supported by New York City, New York State, and the Environmental Protection Agency.

New York Harbor’s health suffered tremendously with the rise of the city’s economy and population during the Industrial Revolution and the first half of the 20th century.  But as we noted in Part 1 of this series, the 1972 Clean Water Act, with its goal that the navigable waters in the US become “swimmable and fishable” by 1985, gave the newly formed (1970) Environmental Protection Agency (EPA) the power to set and enforce pollution control standards, setting the stage for sweeping transformations of the country’s waterways in the years to come.  In Part 2, we’ll focus on New York Harbor’s comeback, continuing to draw from a presentation by John Waldman of Queens College, author of Heartbeats in the Muck: The History, Sea Life, and Environment of New York Harbor.  Waldman delivered his presentation at a Billion Oyster Project Curriculum and Community Enterprise for Restoration Science colloquium this February, speaking about the past, present, and possible future of the harbor to a group of NYC public school teachers participating in our BOP Schools program.  Waldman is a Biology professor who focuses on aquatic conservation biology who previously worked with the Hudson River Foundation for Science and Environmental Research.

While New York Harbor had endured centuries of pollution, Waldman explained that after the passage of the Clean Water Act, the unique properties of the Hudson River Estuary lead to immediate changes in life around the harbor, noting, “The flushing action [in New York Harbor] is so extreme that if you turn off the spigots of pollution” you get a fast response.  One of the most important ways the CWA accomplished this was to spur the improvement and construction of wastewater treatment plants (WWTP) to keep billions of gallons of raw sewage out of the water.  Several WWTP existed in New York City prior to the Clean Water Act, but the EPA pushed the city to build new plants and make significant improvements to the old ones, providing both funding and financing for this work.  (You can see evidence of this in the two signs from the top of the post.  Last year, for example, it provided $187 million to New York State for water infrastructure projects, including both drinking and sewage systems.)

Why is sewage so important?  There’s the obvious unpleasantness of contemplating everything New Yorkers flush down the toilet, but the significance of sewage has to do with several factors, including pathogens.  While gross, poop itself- and even the normal bacteria in poop- doesn’t necessarily make a person sick. (A New York Magazine post on the topic quoted an NYU microbiologist who wrote, “No matter who you are, I can culture your body and find fecal organisms, part of your natural skin flora…Even if you’re fastidious and clean, you cannot wash it away.”)  But when a person or warm-blooded mammal is sick, their fecal matter can contain potentially harmful microorganisms like salmonella that can endanger public health.  (In fact, a typhoid fever outbreak caused by fecal pollution of oyster beds in 1924 lead to the nation’s extremely stringent laws and monitoring programs on shellfish aquaculture under the National Shellfish Sanitation Program.  Under this program, New York Harbor is considered “closed” for shellfish harvest- it’s one reason why Billion Oyster Project’s oysters are for restoration, not for eating.)

By treating sewage for pathogens, New York Harbor experienced an exponential drop in fecal coliforms.  Fecal coliforms are a type of bacteria that indicate the presence of fecal pollution, and they’re measured as a count of bacterial cells per 100 milliliters of water.  The graph below from “New York Harbor Water Survey Program: Celebrating 100 Years” from the NYC Department of Environmental Protection (DEP) shows that from the time of the Clean Water Act to 2009, water quality surveys saw a decrease from over 1000 fecal coliforms per 100 mL to closer to 10 by 2009.

Screenshot 2017-03-06 14.43.28

Graph via the NYC DEP (page 5).

(If you’d like to learn more and try out some hands-on pathogen monitoring, sign up for our upcoming PD, “Environmental Microbiology,” or read our recap of last year’s event here.

If you’re interested in more context and ways to get involved, you might want to check out S.W.I.M. Coalition, a group dedicated to ensuring swimmable waters around New York City.  They put out a Clean Water Steward Workbook that teachers might find useful [though it’s always recommended to cross reference this and other advocacy guides with the latest information on government agencies’ websites].  It notes that values under 200 fecal coliform cells per 100 mL are considered safe for swimming, but that the EPA has recommended the adoption of a new test for Enterococcus, bacteria that “are more able to survive in saltwater” and as such are “a more scientifically accepted indicator of sewage pollution in coastal recreational waters.”  The NYC DEP monitors for both fecal coliforms and Enterococcus year round all over the harbor, while the New York City Department of Health and Mental Hygiene [NYC DOHM] tests only for Enterococcus weekly during the recreational season at the city’s bathing beaches.  You can see the DEP’s data here and the DOHM’s data here.  Currently, the EPA recommends that states adopt their 2012 recreational water quality criteria while the agency considers a new indicator of fecal contamination- coliphages, a subset of viruses that attack E. coli bacteria.  Stay tuned!)

The map below from a Bloomberg-era DEP report offers another visualization of the role wastewater treatment plants played in lowering New York Harbor’s fecal coliform levels, highlighting improvements from 1974 to 2002:

Screenshot 2017-03-06 15.19.09

The presence of fecal pathogens made huge portions of New York Harbor unswimmable before the Clean Water Act, but wastewater also made the harbor less fishable.  This problem stems from the fact that the bacterial decomposition of raw sewage uses up a tremendous amount of dissolved oxygen in water, and fish and other marine organisms need that oxygen to live.  (We recently posted a student friendly explainer on hypoxia [the condition of having low oxygen, commonly known as a “dead zone”] in waterways here.)  In Waldman’s presentation, he used the slide below to illustrate the progress that’s been made after two key dates- 1906, when the New York Metropolitan Sewerage Commission (MSC) was established, and 1972, when the CWA passed.  (Sign up for our Water Chemistry PD to explore this in more detail.  You can also look at recent and historical dissolved oxygen data from the NYC DEP here.)

Screenshot 2017-02-24 09.55.24

Slide courtesy of John Waldman.

New York City now treats 1.3 billion gallons of wastewater a day.  It’s a remarkable engineering achievement in a city with a 100 year-old sewer system.  But we can and should do better.  Riverkeeper notes:

More than 27 billion gallons of raw sewage and polluted stormwater discharge out of 460 combined sewage overflows (“CSOs”) into New York Harbor alone each year. Although water quality in New York Harbor and throughout the Hudson River Estuary has improved significantly over the last few decades, many parts of the waterfront and its beaches are still unsafe for recreation after it rains. As little as one-twentieth of an inch of rain can overload the system. The main culprit is outmoded sewer systems, which combines sewage from buildings with dirty stormwater from streets.

Image via Wikimedia Commons.

Combined sewer overflow diagram via Wikipedia.

Riverkeeper’s CSO page and S.W.I.M. Coalition’s Clean Water Steward Workbook have suggestions on how NYC can address these problems and how you can get involved.  You might also want to look at the NYS Department of Environmental Conservation’s “Sewage Pollution Right to Know” page, which includes lots of background information, a way to sign up for sewage pollution alerts, and links out to resources like their two page PDF “I Flushed.  Now What?

Although New York City’s sewage pollution is a lingering problem, industrial pollution has been dramatically curbed.  In an article reflecting on the legacy of the Clean Water Act, Riverkeeper’s boat captain John Lipscomb reflected, “We have in fact stopped a lot of the traditional sources of pollution.”  The article notes that he’s “referring to environmental battles to halt the toxic dumping by oil companies, cement manufacturers, beer distributers, even chicken processors along the Gowanus and other New York City waterways. (He recalled once spotting blood and feathers coming out of an outflow.)”  The EPA’s Superfund program, created in 1980, is helping to mitigate past industrial pollution of New York’s waterways.  This program forces the polluters responsible for damaging a site to pay for the clean up.  Currently, projects overseen by the EPA are underway at two Superfund sites- Newtown Creek and the Gowanus Canal.

And the garbage dumping issue we looked at in Part 1?  It took longer than it should have, but in 1992 New York City finally stopped dumping garbage in the ocean, after Congress banned the practice in 1988.  (This garbage was in the form of sewage sludge.  New York City was forced by a court order to stop dumping municipal solid waste in the ocean in 1934.)  Garbage still ends up in New York Harbor via CSOs, illegal dumping, and the wind, and additional plastics enter the Harbor as microbeads, although thanks to legislation signed by President Obama, the “Microbead-free Waters Act” is phasing out products with microbeads starting this year.

Today, as Waldman pointed out, “the system is not necessarily healthy but it’s come back in an enormous way.”  Biodiversity is returning to the waterways and some endangered animals like the Atlantic sturgeon are experiencing a comeback.  Fish like menhaden are returning to the harbor, and chasing after them are increasing numbers of whales.  One whale, nicknamed “Gotham,” became a local celebrity after he was spotted cruising up the Hudson in the west 60s and near the George Washington Bridge.  When asked on NPR if this was a good sign for the health of the river, Paul Sieswerda, president of Gotham Whale, said “Yes, absolutely. These fish are actually filter feeders, so they feed on very minute plankton and algae. So these fish are coming back in great abundance, and they are bringing the whales back to New York.”

new york whale

A humpback whale in New York Habor in 2014 via Gotham Whale, a New York City-based whale research and advocacy organization.

Looking forward, what can we expect?  If we’re successful at Billion Oyster Project, by 2030 we’ll have a billion oysters covering 100 acres of reefs, and they’ll be able to filter the standing volume of New York Harbor every three days.  We can expect more challenges from climate change as rainfall increases, some that oysters can help mitigate.  And as the New York Times notes, if “the EPA’s authority wanes,” thanks to 1960s litigation from Scenic Hudson, “private citizens have standing to sue over environmental issues.”

New York Harbor belongs to all of us, and we all have to take care of it!  Whether you’re a teacher, student, local food lover, citizen scientist, restaurant owner, or just a New Yorker who loves your waterfront, we’ve got lots of ways for you to help restore New York Harbor- click “Get Involved” at the top of the page to find out more!