City Soakers: 6 Projects That Will Be Like Sponges for NYC Stormwater

Every year, nearly 30 billion gallons of raw sewage and polluted stormwater flow directly into New York City waterways—the Hudson, East, and the Bronx River, among others—thanks to the city’s outdated, overtaxed wastewater system. The Gowanus Canal alone has 13 Combined Sewer Overflow sites.

Among the actions the New York City Department of Environmental Protection is taking to reduce sewage in our waterways is the Green Infrastructure Grant program. Part of the NYC Green Infrastructure Plan, the grants fund projects that capture rain from impervious surfaces on private property, ultimately keeping it from entering the sewer system.

Last month, six projects were granted more than $3 million in funding through this program. Once completed, these projects should capture more than 6 million gallons of stormwater each year.

“By soaking up rain water these projects will help to reduce pollution in our local waterways, including the East River, Gowanus Canal and Jamaica Bay,” DEP Commissioner Emily Lloyd said in a written statement announcing the grants.

A new round of grant funding will be made available in 2015 for private property owners throughout the city.  More information can be found on DEP’s website here.

The 2014 Green Infrastructure Grant Winners:

Gowanus Arts Rooftop Farm – Park Slope/Gowanus, Brooklyn

Proposed plans for the Gowanus Arts Rooftop Farm and Garden.

The Gowanus Arts Building is a three-story former soap factory with a 6,000-square-foot that will soon house a green roof with vegetable gardens and riverstone blue roof to retain and slow the flow of stormwater from the roof. The vegetable gardens will be used and enjoyed by the building tenants, most notably Spoke the Hub, which has a children’s nutrition, healthy eating and cooking program. The project will manage more than 9,300 gallons of stormwater during each storm.

Madani Halal Rooftop Farm – Ozone Park, Queens

NYER031215_2Madani Halal is an industrial abattoir and meat processing facility located in Ozone Park, Queens. The proposed project will involve the installation of intensive green roof vegetable gardens on two of the property’s roofs. The green roofs will absorb nearly 9,000 gallons of stormwater.  It is located within the Jamaica Bay watershed.

Montefiore Moses Campus – Norwood, Bronx

NYER031215_3Montefiore’s green roof project will be constructed atop a parking garage that is located adjacent to a 28-story residential building that houses Montefiore’s Residents/House Staff. The design includes both extensive green roof systems that will be accessible to residents. The project is located within the East River watershed and will manage more than 15,000 gallons of stormwater.

Paradise on Earth Community Garden – Morrisania/Melrose, Bronx

NYER031215_4The New York Restoration Project’s Paradise on Earth Community Garden is located within the East River watershed and is comprised of three lots totaling approximately 10,807 square feet. The garden renovation will include retrofitting existing features into permeable paving and rain gardens/vegetated swales. NYRP’s goals for the garden renovation include facilitating environmental education, supporting urban agriculture, providing a green oasis for the community, and hosting local artist and cultural events.  The project will manage approximately 15,000 gallons of stormwater.

Salmar Building Roof Meadow – Sunset Park, Brooklyn

NYER031215_5The Salmar Building is mixed commercial/industrial building located in Sunset Park, Brooklyn. The project will involve a 61,050-square-foot green roof seeded with meadow plant mix. The featured plant on the roof will be native blue lupine, which is known to attract the endangered Karner Blue Butterfly.  The project will manage 105,000 gallons of stormwater.

BAM South – Ft. Greene/Downtown, Brooklyn

NYER031215_6BAM South is a new construction project, developed by DUMBO-based Two Trees Management, that will incorporate a green roof on the 3rd floor roof. This space will not be directly accessible to residents or visitors but will be visible from a public lobby and the residential units above. Due to the inaccessible nature of the space, the project will be cultivated as a habitat node for pollinators.  The project will manage more than 9,500 gallons of stormwater within the East River watershed.

Calling All Lovers of the Bronx River!

The Bronx River needs your help. Your feedback is wanted at a meeting with the City this Thursday night about how to make the Bronx River cleaner and healthier.

The City says it is investing $26 million in order to reduce the volume of untreated sewage and stormwater released into the river from over 1 billion gallons per year to 592 million gallons annually.

“River of High Bluffs”

Have you had a chance to visit the Bronx River? The Bronx River Alliance provides the following interesting description of the river and its history…

To walk along the Bronx River today is to enter a world slightly apart from the city, where the cry of the redwing blackbird is louder than the hum of cars not twenty feet away.

One of the little-known marvels of the New York City landscape, the 23-mile Bronx River winds down through southern Westchester and the Bronx to define a peaceful corridor of greenery for fishing, strolling, biking, boating and nature study amid the noise and bustle of urban life. It is the only major watercourse within the city limits that is not entirely tidal.

Credit: Bronx River Alliance

Called Aquehung or “River of High Bluffs” by the Mohegan Indians who first lived and fished along it, the river attracted European traders in the early 1600s for the sleek, fat beaver that proliferated there….The [river’s] water was considered so “pure and wholesome” that during the 1820s and 1830s the New York City Board of Aldermen debated ways to tap into it to supply the growing city with drinking water…

Raw Sewage Releases Threaten the City’s Waterways

While much progress has been made in restoring New York City’s rivers, creeks and bays, they are still threatened by various types of pollution. One ongoing source of contamination is the City’s release of untreated sewage and stormwater into waterways like the Bronx River.

Approximately 70 percent of New York’s sewers are combined. This means that household and industrial wastewater, rainwater, and street runoff -1.3 billion gallons daily- are all collected in the same sewers and conveyed together to the City’s 14 treatment plants.

During heavy rains or snow, combined sewers can fill to capacity and are then unable to carry household and storm sewage to treatment plants. The mix of excess storm water and untreated sewage must be released directly into the city’s waterways.

There are over 400 combined sewer overflow release points throughout the five boroughs. Four of them are in the Bronx River.

In total, almost 30 billion gallons of raw sewage and polluted stormwater are discharged annually into New York City’s waterways. The releases cause environmental damage, and put boaters, swimmers, fishing enthusiasts and other New Yorkers into potential contact with pathogenic bacteria and other toxic substances.

A Plan for the Bronx River

in the next three years, the City must produce plans for ten separate water bodies or “sewer sheds” – areas of the city where raw sewage is released into waterways.

The State of New York must sign off on each plan, as it is responsible for enforcing federal Clean Water regulations. The plan for the Bronx River is supposed to be completed and submitted to the State by June, 2015.

Some advocates say the City is not taking the long term CSO reduction plans for each sewer shed seriously enough. They maintain that the plans submitted thus far -for Alley Creek, the Hutchinson River, Westchester Creek and Flushing Creek- do not include significant pollution reduction targets.

Add Your Voice

Learn more about what is being done to address CSO releases and give your feedback on how to make the Bronx River cleaner and healthier.

Residents will be meeting this Thursday, February 12th with the City’s Department of Environmental Protection to discuss DEP’s long term CSO control plan for the Bronx River.

The meeting will take place at Casita Maria Center for Arts and Education,

928 Simpson Street, 6th Floor, the Bronx, from 6pm to 8pm.

To RSVP please email or call 718-595-4148.

Read more about DEP’s Combined Sewer Overflow program for the city’s waterways.

Issues to Watch in 2015: Raw Sewage Releases into NYC Waterways

Throughout January, we will be featuring critical local environmental issues that are likely to see significant action this year.


In bright sunshine, a group of New Yorkers in flowing garb wades into the waters of Coney Island Creek. They run their arms through the glistening water, and then raise their hands in prayer.

This beautiful scene appears in a short film about Coney Island Creek by Charles Denson which shows the love that local residents have for the Creek, and the multitude of ways they use it.

Coney Island Creek, like all of the City’s waterways, has endured decades of pollution and a host of environmental stresses. One major source of pollution into the Creek has been the periodic release of untreated sewage and stormwater from a sewer outflow point.

The City says it has invested $166 million in order to drastically reduce the releases to a level of 37 million gallons entering the Creek per year.

Thirty Billion Gallons

In total, almost 30 billion gallons of raw sewage and polluted stormwater are discharged annually into New York City’s waterways. The releases cause environmental damage, and put kayakers, swimmers, fishing enthusiasts and other New Yorkers into potential contact with pathogenic bacteria and other toxic substances.

Environmental groups and the State of New York say the City is not doing enough to ensure that local waterways like Coney Island Creek and Jamaica Bay are safe for public use all year round.

A fundamental dispute between the City and the State is how far the City should be expected to go to meet the goals of the federal Clean Water Act- that all public waterways be fishable and swimmable.

Advocates also say that the City’s efforts to address the problem do not incorporate public input in a meaningful or transparent way.

“The [City’s] current LTCP [Long Term Sewage Overflow Control Plan] development process is deeply flawed, both in process and in substance,” said a coalition of watchdog and environmental groups in a recent letter to the City.

The City argues that it has made significant progress, more than doubling the amount of raw sewage captured prior to storm-related releases. Almost $2 billion has been spent to control raw sewage discharges, and there are plans to spend $2 billion more, they add.

Last month, the State announced plans to update its water quality regulations. This pushes the issue forward, and may compel the City to adopt more stringent sewage control goals than are currently in place. The public can ask questions and offer their opinions about the updated standards at a hearing with state officials on January 27th.

Raw Sewage Releases: A Systemic Issue

Approximately 70 percent of New York’s sewers are combined. This means that household and industrial wastewater, rainwater, and street runoff -1.3 billion gallons daily- are all collected in the same sewers and conveyed together to the City’s 14 treatment plants.

During heavy rains or snow, combined sewers can fill to capacity and are then unable to carry household and storm sewage to treatment plants. The mix of excess storm water and untreated sewage must be released directly into the city’s waterways.

There are over 400 combined sewer overflow (CSO) release points throughout the five boroughs. As little as one-tenth of an inch of rain can trigger a CSO release. This happens about 75 times per year, say environmental groups.

And the issue is becoming more pressing as local rainfall becomes more frequent and intense due to climate change.

A State-Mandated Plan for Pollution Control

CSO releases are technically a violation of the federal Clean Water Act. To remedy this, the City is in the midst of executing a three-part strategy to reduce the releases as required by a 2012 “Consent Order” it has entered into with the State.

First, the City has committed to spending $1.6 billion more on grey infrastructure, which would ultimately reduce CSO discharges by an estimated 8.4 billion gallons per year. Recent grey infrastructure projects completed by the City include upgrades to wastewater treatment facilities, storm sewer expansions and the construction of CSO retention tanks.

Second, the City has committed to installing green infrastructure, like green roofs, porous pavement and “bioswales” (large curbside plantings), that will absorb one inch of rainwater across 8,000 acres of the city. The 8,000 acres represents 10 percent of impervious surfaces, like streets and sidewalks, in all areas of the city with combined sewers.

The idea is to capture stormwater run-off before it reaches and overwhelms sewers, reducing CSO releases by another 1.5 billion gallons per year.

Finally, in the next three years, the City must produce plans for ten separate water bodies or “sewer sheds” – areas of the city where raw sewage is released into waterways.

Addressing the City’s “Sewer Sheds”

According to the City, the goal of each plan “is to identify appropriate CSO controls necessary to achieve waterbody-specific…standards, consistent with the Federal CSO Policy and the water quality goals of the Clean Water Act.”

Each sewer shed plan will contain some combination of green and grey infrastructure solutions. The State must sign off on each plan, as it is responsible for enforcing federal Clean Water regulations.

The City’s schedule for completion and submittal of its long-term CSO control plans runs through 2017:

  • Alley Creek- June, 2013
  • Westchester Creek- June, 2014
  • Hutchinson River- September, 2014
  • Flushing Creek- December, 2014
  • Bronx River- June, 2015
  • Gowanus Canal- June, 2015
  • Coney Island Creek- June, 2016
  • Jamaica Bay and Tributaries- June, 2016
  • Flushing Bay- June, 2017
  • Newtown Creek- June, 2017

The ten area plans will form the basis of a citywide CSO reduction plan to be completed by the end of 2017.

Advocates say that the goal is to find cost-effective ways to achieve the “highest attainable use” for each of the city’s water bodies. But the City does not appear to be in agreement with the State and environmental groups about what is actually attainable.

Struggling to Reach Agreement on Water Quality Standards

All sides agree that the City is making real progress on a number of fronts, including its construction of hundreds of green infrastructure projects throughout the five boroughs.

Nonetheless, the State Department of Environmental Conservation has rejected the first long-term plan submitted by the City, which covers Alley Creek in Queens. At issue is to what extent the City actually plans to clean up Alley Creek. The City aimed lower than what the State says is required by federal law.

The State and the City are now in litigation.

Alley Creek flows through Alley Pond Park, the 2nd largest park in Queens. Photo by Maxmaria.

The long-term goal should be that all of New York City’s waterways are “fishable and swimmable,” argues the State. The new water quality standards released by the State this past December are a “big deal,” Larry Levine, a senior attorney with the Natural Resources Defense Council’s water program, told NYER.

The NRDC is reviewing the draft standards now, as is the City. A recent article by Levine for the NRDC staff blog argues that New York City leads the U.S. in the category of “most untreated sewage discharged to waterways.”

The City is not taking the long term CSO reduction plans for each sewer shed seriously enough, says Levine. He maintains that the plans submitted thus far -for Alley Creek, Hutchinson River, Bronx River and Flushing Creek- do not include significant pollution reduction targets.

This jeopardizes the overall effort to support truly healthy local water bodies, say advocates.

“The first two parts of the [2012] agreement [between the City and the State],” observed Levine, “are projected to reduce annual sewage overflows by about 12 billion gallons per year. That still leaves 18 billion gallons…that’s why the third part of the deal is so critical. The Long Term Control Plans are meant to close the gap.”

The City declined to comment on Mr. Levine’s article.

“The Issue Is Cost”

The City responds to its critics by arguing that it is doing everything it can with the financial resources at hand. Projects to improve harbor water quality are not funded by City tax dollars. Rather, the city’s water rate payers –building owners and ultimately their tenants- pick up the tab for new infrastructure.

The Department of Environmental Protection is responsible for developing and implementing the City’s CSO reduction plan. The agency oversees New York City’s water supply, sewage treatment and stormwater management systems. The DEP is also responsible for making sure that local waterways are in compliance with state and federal Clean Water regulations.

At a public meeting in December, DEP Commissioner Emily Lloyd stated that the agency was retiring about a half billion dollars in debt every year, and adding a “couple billion more” annually.

Current efforts to control sewage and stormwater releases –per the 2012 agreement with the State- will only add more debt, Lloyd said.

Questions About Public Participation

As part of its planning process, the DEP holds a public meeting each time it completes a CSO reduction plan and is preparing to submit it to the State. For instance, a public meeting to discuss the City’s CSO reduction plan for the Bronx River is scheduled for February.

Contrary to the step by step environmental review process that typically exists for development projects, legislative updates, etc., there is no formalized public oversight as the City develops its long-term CSO control plans. The DEP acknowledged at a public meeting in December that it does not share the plans with the public before they are submitted to the State for review.

Instead, a PowerPoint summary is presented at the meeting for each sewer shed. The public can ask questions at the meeting and submit comments in writing. Advocates say it is unclear what happens to these comments.

A November 17th letter to DEP Commissioner Emily Lloyd from the SWIM [Stormwater Infrastructure Matters] Coalition stated that, “we cannot emphasize strongly enough that it is impossible at this time for us or any member of the public to evaluate DEP’s proposal or its underlying analysis, as the public is merely provided a PowerPoint presentation.”

SWIM’s steering committee includes representatives from Riverkeeper, the Natural Resources Defense Council and the Bronx River Alliance.

The letter, which was submitted in response to the Flushing Creek plan, said the City’s PowerPoint “was missing essential information” such as “CSO volume reductions and water quality improvements” that would result from the different options -grey and green- available to the City.

Why had the City gone with a disinfection strategy for addressing raw sewage releases, SWIM asked. “As presented, the DEP gave the public absolutely no information as to their green infrastructure plans for this watershed,” they added.

Before submittal to the State, the City “should publish -for public comment- the actual plans,” SWIM argued.

SWIM also maintained that in its presentations to the public, the City has not been clear about what the State mandated for each long term control plan. The City’s roles and responsibilities as required by the 2012 consent order should be transparent, said the Coalition.

The DEP declined to comment on the November 17th letter from SWIM.

Swimming event in New York Harbor. Photo by Jay Fine.

Every year, more New Yorkers are returning to the waterways that surround our city. From kayaking in Jamaica Bay to swimming in the Hudson River, we are re-connecting with our coastal habitat of islands, rivers, creeks and bays.

This year, the City and State will continue to debate (or litigate) the fundamental implications of the Clean Water Act for New York City’s waterways. Environmental groups will be watching to see whether the City’s sewer shed plans will reflect any progress made in this conversation.


More information about the City’s efforts to control CSO releases and its Long Term Control Plan can be found here.

Written comments regarding the State’s updated water quality standards may be submitted on or before Monday, February 2nd.


Green for Green: NYC DEP Makes Funding Available for Projects that Curb Stormwater

The New York City Department of Environmental Protection announced that it will make $5 million available to community groups, property owners, and nonprofit organizations for green projects that “improve the health of local waterways and enhance community life.”

The Green Infrastructure Program, which is entering its fourth year, focuses primarily on projects that address storm water issues and help absorb rainwater that would otherwise contribute to combined sewer overflows into local waterways. This includes the design and construction of green and blue roofs, rain gardens, rain water harvesting or reuse systems, and permeable or porous surface installation.

This funding announcement comes at a time of renewed focus on the impacts of climate change on New York City infrastructure. As NYER has reported previously, climate change will likely cause New York to become a wetter city, subject to more frequent and intense rainfall—and thus, more overloaded sewers and water-related health risks.

“Investing in green infrastructure is a cost-effective way to improve the health of our local waterways, clean the air, green the landscape, increase shade and cool temperatures during the summer while also engaging all New Yorkers in the important work of protecting the environment,” said DEP Commissioner Emily Lloyd.

Grant Details

While all private property owners served by combined sewers in NYC are eligible for the Green Infrastructure Program, preference will be given to projects that are located in priority watersheds, are cost-effective, provide matching funds or other contributions, and “include ancillary environmental and community benefits such as increased shade, decreased energy use for cooling buildings, increased awareness about stormwater management, and green jobs development.”

The DEP will host three workshops to explain the eligibility requirements and guide users through the online application, which must be completed by November 13.  A fourth technical workshop will be held at DEP headquarters to provide support in computing stormwater calculations and to review conceptual ideas with DEP engineers prior to submitting an application.

October 16, 6:00-7:30PM
Bronx Courthouse – 265 East 161st Street

October 21, 6:00-7:30PM
High School for the Arts – Auditorium
345 Dean Street

October 22, 6:00-7:30PM
The Horticultural Society of New York
148 West 37th Street – 13th Floor

Queens (Technical Workshop)
October 28, 2:00-5:00PM
DEP Headquarters
59-17 Junction Boulevard – 3rd Floor Cafeteria

Notable Projects

Over the last three years, the DEP says it has committed more than $11 million to fund 29 different green infrastructure projects through this grant program, resulting in the retention of 13 million gallons of stormwater.

Some of the notable projects funded in past years include:

Brooklyn Navy Yard

Brooklyn Grange Photo credit: NYC DEP

Amount: $592,730
Location: 63 Flushing Avenue, Building No. 3, Brooklyn Navy Yard
Description: In partnership with Brooklyn Grange, the Brooklyn Navy Yard constructed a 40,000-square-foot commercial rooftop farm.  The rooftop farm manages over one million gallons of stormwater per year and reduces CSOs to the East River. The production of fresh local produce creates opportunities for urban agriculture jobs training and volunteerism, education and advocacy.

Osborne Association

Photo credit: NYC DEP

Amount: $288,000
Location: 809 Westchester Avenue, Longwood, Bronx
Description: Osborne Association’s project features an alternating blue roof and green roof system on its building in the Bronx. Green roofs are vegetated roof installations that can absorb rain water in the soil and plants. Blue roofs detain stormwater in trays to create temporary storage and gradual release of the stormwater. This project manages over 240,000 gallons of stormwater per year and reduces CSOs to the East River.

Lenox Hill Neighborhood House

Photo credit: Honest Buildings

Amount: $40,000
Location: 331 East 70th Street, Lenox Hill, Manhattan
Description: The Lenox Hill Neighborhood House built two rooftop gardens that manage up to 63,000 gallons of stormwater per year and provide its clients with fresh vegetables. The rooftop gardens capture rain water and reduce CSOs to the East River.

Fecal Map NYC: The Worst Places to Swim in the City

Today’s post comes to us via I Quant NY, a fantastic blog that uses NYC Open Data to tell stories about our city. I Quant NY is authored by Ben Wellington who is a Visiting Assistant Professor in The City & Regional Planning Program at The Pratt Institute in Brooklyn, where he focuses on the cross section of Open Data and City Planning.

Thank you for letting us re-publish your post, Ben!

If you have ever tried to visit a NYC beach shortly after it rains heavily, you may be disappointed to find that beach closed.

The reason is one of every NYC environmentalist’s worst nightmares: Combined Sewer Outflows (CSOs). Put simply, New York City’s sewage goes to the same place as its street drainage. That works fine until we get so much rain that the sewage treatment plants can’t handle both the storm water and the sewage flowing through our sewers. As a result, this combination of stormwater and sewage overflows and that resulting backup is released into our very own New York City waterways. For the curious, check out this great page by the DEP which include descriptions of CSOs and maps of the outflows.

So back to the beach— what causes it to close exactly? Well, the city monitors its waterways for Fecal Coliform, something that is as gross as it sounds. Specifically, its a bacteria that grows in the intestines of warm blooded animals. High level of fecal coliform indicates a high probability of raw sewage in the water. If levels go above 1,000 coliform per 100ml of water, beaches are closed in accordance with state regulations.

To find the dirtiest water in New York City (or at least the most sewage-full water, since there are many different ways to measure water quality), I turned to Harbor Water Sampling Data released as Open Data by the DEP. The dataset includes samples from dozens of sites back to 2008.

I explored the mean, minimum, median and max levels of fecal coliform at each site, but to decide which area was the dirtiest, I calculated the percent of days sampled at the site that registered as too dirty to swim in (i.e. above the safe level of 1000 coliform / 100ml).

The Top 10 dirtiest water sample locations by that measure are below:


The dirtiest water? Coney Island Creek, which sits between Coney Island and the rest of Brooklyn. Not far behind it is Bergen Basin, near JFK. These two are at the top of the list by the mean measurement as well. The Bronx River is number 3, Alley Creek is 4 and Bergen Basin comes back for number 5. At all five of these spots, samples came in as having too much fecal coliform to swim in more than half the time! So I mapped out these five “fecal hot spots” below:


Spots 6 – 10 go to two sites in the Gowanus Canal, Flushing Creek and another site in both The Bronx River and Coney Island Creek.

To expand beyond the top 10 spots, I created the interactive map below, which includes all of the harbor locations that were measured in the DEP data. Just like the analysis above, I mapped the percentage of time that water levels were unsafe for swimming. Larger circles indicate a higher percentage of unsafe days, and thus dirtier water. Clicking on a circle gives you fuller details for that site.

Note that the larger circles appear more inland. The conclusion? If you are going to swim in NYC, I guess the rule of thumb is to stay away from anything with the word “creek” in its name (and of course “canal”) and head toward the rivers. The one exception seems to be the Bronx River. I suppose its sort of intuitive… interior waterways have much less water to dilute waste matter and they generally move slower than their large river counterparts. (Of course this is more of a theoretical swim. If you are ACTUALLY going to swim, hit up the beaches!) The best part of all of this? I may have just discovered the origin of the old saying “Up sh*t creek without a paddle.”

-Analysis done in Excel (pivot tables)
-Map formed in QGIS and then exported to CartoDB
-All Data used can be found here.

For the latest I Quant NY data analysis of this great city, sign up for the mailing list (about one post a week), like I Quant NY on Facebook or follow I Quant NY on Twitter. I tell stories with data.


Changing Climate Makes City Stormwater Management Harder, Health Risks Higher

On August 13th, New York State witnessed the greatest 24-hour rainfall, 13.27 inches, in its recorded history. The state record – last set in 2011 – was broken in West Islip, Long Island, fewer than 30 miles from the Queens border.

A flash flood watch went in effect throughout New York City, and beaches in Brooklyn and Staten Island were closed to swimmers the following day. The heavy rain had overloaded sewer mains, necessitating the release of untreated sewage directly into local waterways.

If the City’s climate scientists are right, New York will steadily become a wetter city, subject to more frequent and intense rainfall – and thus, more overloaded sewers and water-related health risks.

And at the very same time that New York’s climate is shifting, the City is engaged in what will be a decades-long effort to address a long-standing problem: the need to capture stormwater before it overwhelms sewers and treatment plants, triggering the release of untreated sewage into Jamaica Bay, the Bronx River, and other waterways.

Average annual precipitation currently ranges between 43 and 50 inches in New York City, depending on location. The New York City Panel on Climate Change notes that, between 1900 and 2011, precipitation in Central Park increased about .7 inches every decade.

Almost 30 billion gallons of raw sewage and polluted stormwater are discharged annually into New York City’s waterways.

And perhaps more importantly, in its Climate Risk Information 2013 report, the Panel adds that “larger percentage increases are expected in the frequency, intensity and duration of extreme precipitation.” The Panel defines an extreme precipitation event as one with more than 1 inch of rain.

Today, as little as a quarter-inch of rain can overwhelm municipal sewers. The end result of extreme – and not so extreme – weather is ongoing contamination of our local environment. Almost 30 billion gallons of raw sewage and polluted stormwater are discharged annually from over four-hundred combined sewage overflows (CSOs) into New York City’s waterways.

The scale of the problem that the City is trying to solve is “huge,” said Larry Levine, a senior attorney with the Natural Resources Defense Council’s water program.

An Over-Taxed Wastewater System

Climate change adds a further layer of complication to what has already been a pressing problem for New York City: stormwater management.

The de Blasio administration is working to address two parallel issues. First, large sections of the city rely on what is now considered an outmoded sewer system.

[A second, entirely separate issue is the fact that areas of the city like Staten Island’s east shore and sections of eastern Queens do not even have proper storm drains. These communities were developed on an “ad-hoc basis”, often in low-lying, marshy areas. Neighborhoods like New Dorp Beach and South Beach on Staten Island, which were devastated by Superstorm Sandy, are now racing against time to put stormwater infrastructure into place.]

Much of the city, however, relies on what is known as a combined sewer system. Household and industrial wastewater, rainwater, and street runoff are all collected in the same sewers and then conveyed together to the City’s treatment plants. Approximately 70 percent of New York’s sewers are combined says the City.

New York City’s 14 wastewater treatment plants together treat 1.3 billion gallons of wastewater daily. The City says it is able to remove about 85% to 95% of pollutants from wastewater before it is disinfected with chlorine and then discharged back into local waterways.

But during heavy rains or snow, combined sewers can fill to capacity and are then unable to carry household and storm sewage to treatment plants. The mix of excess storm water and untreated sewage must be released directly into the city’s waterways.

Find the CSO release site closest to you.

Major Improvement but Water Quality “Failures” Persist

There are two equally valid stories to be told about the quality of New York City’s waterways, which is heavily impacted by stormwater management.

On the one hand, water quality has improved significantly; to the point where swimmers, kayakers, and other recreators are seen with greater frequency in more and more sections along the city’s coastline. Wildlife has also responded to improvements in local water quality.

Indeed, New York City residents might be surprised to see the results of a recent six-year study which looked at 15 Hudson River estuary sites in the five boroughs. The majority of samples collected from sites like the Dyckman Street Beach in the Bronx, the Pier 96 Kayak Launch, and the Battery found that the water was safe for swimming.

The study, carried out by Hudson Riverkeeper, in conjunction with CUNY Queens College and Columbia University’s Lamont Doherty Earth Observatory, actually collected data from 74 estuary locations between New York Harbor and Waterford, Saratoga County.

Nonetheless, the other story is that one-quarter of the water samples collected from the 15 New York City estuary sites failed U.S. Environmental Protection Agency “safe swim guidelines” for fecal contamination.

Last year, New York ranked 20th in beach water quality out of thirty states.

Perhaps more telling, the percentage of failing New York City samples jumped from ten percent in dry weather to thirty-five percent after wet weather. Wet weather was defined as at least one-quarter inch of cumulative rainfall in the preceding three days.

The entire state is facing similar issues. Last year, New York ranked 20th in beach water quality out of thirty states, the Natural Resources Defense Council found. Thirteen percent of samples collected at local beaches throughout the state exceeded EPA “safe swim” bacterial levels.

Combined sewage overflow (CSO) releases are seen as a primary culprit in local waterway fecal contamination.

Toxic Releases and Their Impact

Untreated human waste, and the pathogenic bacteria and viruses that come with it, is the most well known component of CSO discharges. The most common illness associated with swimming in sewage-polluted water is gastroenteritis, says the EPA.

Gastroenteritis occurs in a variety of forms that can have one or more of the following symptoms: nausea, vomiting, stomachache, diarrhea, headache or fever. Children, the elderly and people with weakened immune systems are most at risk.

Swimmers and others who cross paths with a CSO release can encounter debris flushed down toilets (syringes, tampon applicators, etc.) and trash washed off city streets. Any substance on city streets, or poured down storm drains, can end up in a CSO.

Riverkeeper’s website provides a disturbing list of compounds that have been found in CSOs: ammonia; pesticides; petroleum products (from gas stations and auto repair shops); toxic metals; and other hazardous substances like paints, oils, solvents and cleaners.

CSO discharges can also damage local ecosystems because their elevated nutrient content can combine with hot weather to create dangerous toxic algae blooms. These blooms are extremely hazardous to humans and animals, and can create “dead zones” in local waterways.

Similarly, CSO releases containing food waste, and dead plant and animal tissue, deplete oxygen needed by fish and plant life to survive.

Trouble in the Gowanus

Gowanus canal detritus. Photo credit: Anthony Fine/Creative Commons.

CSO releases into the Gowanus Canal in Brooklyn have been documented for years by local residents who say that the canal becomes “one huge toilet” after a major rainfall.

“Last night’s [July 2nd, 2014] heavy rain caused another Combined Sewer Overflow event,” wrote neighborhood resident and local blogger Katia Kelly.

“By 11 PM, much of the waterway was covered with raw sewage. The smell was unbelievable…It is unfathomable to think that the new residents of the 700 unit Lightstone Group Project at the shores of the canal will have to deal with this every time it rains heavily.”

In the aftermath of the July 2 storm, and following other major downpours, residents in the nearby Gowanus Houses public housing development have also reported that raw sewage backs up into their kitchen sinks.

One of those residents happens to work for local City Council Member Steve Levin. Levin said that he had spoken with the City’s Department of Environmental Protection and the Housing Authority about the back-ups. “It’s hard to say what’s going on,” he stated, but added that he believed the back-ups were caused by “some combination” of the CSO releases into the canal, and plumbing issues within the development itself.

Levin stressed that NYCHA had been very responsive in dealing with similar issues at other developments in the area. He also noted that long-term clean-up plans for the Gowanus Canal included “sewage holding tanks” that would help to control the releases.

“We would like to see as much of an effort as possible,” Levin said, “to determine what’s going on in the intervening years before all of the [sewage management] infrastructure is implemented.” He said it would be “helpful” if DEP could examine all of the existing infrastructure in the surrounding area and “make sure that everything is in good repair.”

Neither the DEP nor the state Department of Environmental Conservation would respond to questions for this story about CSO releases into the Gowanus Canal, or sewage back-ups at the Gowanus Houses.

The Public’s Right to Know

Residents in Gowanus and other neighborhoods cannot obtain real-time information on rain-related releases from individual CSOs, despite 2012 state legislation requiring “publicly owned treatment works to report discharges of untreated or partially treated sewage.”

According to state law, residents must be notified within four hours of a sewage overflow. The state DEC must report the estimated amount of the overflow, the location and duration, the reason, and a description of steps taken to control the release from happening again.

The lack of publicly-available data on rain-related CSO releases is technically a violation of state law, said Phillip Musegaas, an attorney with Riverkeeper and director of its Hudson River Program. But, he added, there is a straightforward reason for the lack of data: the City does not know exactly how much sewage is coming out of each of its 426 CSO release points during rain events.

The City estimates the size of releases using modeling based on the amount of rainfall and the impact of similar rain events in the past. City residents can check online to see if a water quality advisory has been issued for their area.

Some of these “areas” are very broad, encompassing multiple neighborhoods, and making it hard to know what is happening at the local level. Musegaas said that Riverkeeper has repeatedly raised the problematic nature of this method of tracking with the City to no avail.

“Why not install monitors on the biggest CSO’s? Pick twenty or thirty,” said Musegaas.

Musegaas added that climate change also made the use of modeling more questionable. “If you’re basing your modeling on one place [rainfall measured at LaGuardia Airport] and one year, that’s a problem.”

Why does the lack of data about releases of raw sewage into an already polluted waterway like the Gowanus matter? “The thing that’s going to make you actually physically ill is what comes from the CSOs – it’s raw sewage,” said Council Member Levin.

Neither the City nor the State responded to questions about how releases from CSOs across the city are tracked.

Some communities living close to CSO release points are taking the lack of real-time data into their own hands. The Newtown Creek Alliance is now attempting to track local CSO releases and alert area residents by text message when flushing their toilets will send waste directly into the creek.

It is important to note that, during the summer months, the City collects and then publishes weekly data about water quality in 70 locations across the five boroughs. The data is published on a monthly basis the rest of the year. The latest available data is from August 18th through August 21st.

What’s the Goal? The City and State Face Off on Water Quality Standards

CSO discharges operate in a grey area relative to federal and state clean water regulations. They are essentially pollution releases that are managed by government.

“The City is supposed to reduce [these releases],” said Larry Levine of the NRDC. “What would be illegal is if they don’t follow through on specific plans [to reduce volume].”

And the City is actively working on a long-term plan to reduce CSO releases based on a series of “Consent Orders” it has entered into with the State. In the next three years, the City must produce plans for ten separate water bodies or “sewer sheds” – areas of the city where raw sewage is released into waterways.

According to the City, the goal of each plan “is to identify appropriate CSO controls necessary to achieve waterbody-specific…standards, consistent with the Federal CSO Policy and the water quality goals of the Clean Water Act.”

The areas targeted for CSO reduction are: Alley Creek, the Hutchinson River, the Bronx River, Coney Island Creek, Flushing Bay, Flushing Creek, the Gowanus Canal, Jamaica Bay and its tributaries, Newtown Creek, and Westchester Creek.

The ten area plans will eventually form the basis of a citywide CSO reduction plan.

However, the state DEC has rejected the first long-term plan submitted by the City, which covers Alley Creek in Queens. At issue is to what extent the City actually plans to clean-up Alley Creek. The City aimed lower than what the State says is required by federal law.

“The City’s proposed long-term CSO control plan unlawfully failed to identify CSO controls that would either clean up Alley Creek enough to allow full fishable/swimmable use or, if that were not attainable, clean up Alley Creek enough to allow…[that] use on a seasonal basis,” Attorney General Eric Schneiderman wrote in a document filed with the New York State Supreme Court this June.

The City “misses the mark,” said Schneiderman, by attempting to only adhere to state water quality standards that are not as stringent as federal standards. “Under the federal Clean Water Act, DEC’s regulation of pollutant discharges to such water bodies as Alley Creek, can be no less stringent than the requirements set by federal law.”

The water quality standards that are ultimately established for Alley Creek could set the tone for the nine other waterbody plans to come, said Levine. The State and the City are now in litigation.

‘Green Infrastructure’ Will be Key

The State and the City have reached agreement, however, on the use of green infrastructure to “improve the overall water quality in New York Harbor waters.”

The idea is to capture and make use of rainwater at the source, before it enters the city’s combined sewer system. By changing its fundamental approach to stormwater management, the City is not only reducing pollution levels in local waterways, it is also preparing for climate change.

A State order requires that by 2030 the City be able to divert the first inch of rain from 10 percent of New York’s impervious surfaces using a green infrastructure “adaptive management approach.”

Examples of green infrastructure projects include: blue roofs and green roofs, which use mechanical devices or vegetation to slow roof water from draining too quickly; porous pavement for parking lots so water can be absorbed into the ground; tree pits and streetside swales for roadways so water can pool in underground holding areas and dissipate in the ground or through plants; wetlands and swales in parks; and rain barrels in some residential areas.

The State’s order requires five-year incremental milestones to meet the 10 percent target, and annual reporting on progress. The City has committed $187 million toward meeting the first five-year target in 2017.

And the City says it will utilize an estimated $2.4 billion of public and private funding over the next 18 years to install more green infrastructure technologies. Through the order, the City maintains flexibility to prioritize green investments in neighborhoods that it says “will benefit most from reductions in combined sewer overflows.”

How much of a difference can green infrastructure make?

The City estimates that its use could lead to the annual removal of approximately 1.5 billion gallons of CSO releases by 2030. Roughly 8.4 billion gallons could be removed by 2045, using green and “targeted” gray infrastructure.

That’s almost one-third of the estimated 30 billion gallons released by CSOs each year.

“Green infrastructure is the right solution,” said Larry Levine. “The City is making some serious progress.” But, Levine cautioned that solutions to the city’s wastewater problem are going to be “long-term.”

And, Levine added, the City “should improve its stormwater management standards for new development projects.” Standards for new buildings should require on-site management – through green infrastructure, not discharge into sewers – “of at least the first one-inch of rainfall in any storm,” Levine said.

A similar approach is already mandated in other parts of New York State.

Instead, the City requires new development sites “to temporarily hold on to runoff and then release it slowly into sewers,” says Levine. “That approach helps to reduce overflows but, by the City’s own calculations, it’s much less effective than keeping that runoff out of the sewers entirely,” he concluded.

The pressure to address stormwater management is unrelenting. At the time this article was being finalized for publication, a flash flood warning was issued for New York City. “Rain rates up to 2 inches per hour are expected,” said the National Weather Service.

And climate change makes the goal of a truly sustainable city – one which no longer pollutes the environment around it – both more challenging and more urgent at the same time.

Is it reasonable to expect that all of the city’s waterways should eventually meet the federal requirement that they be swimmable and fishable?

“Absolutely,” responded Phillip Musegaas. “That’s what the Clean Water Act calls for…to make sure that these public resources are healthy…It’s a good goal to have.”