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Solutions for New York City’s Sewer Problem

   /   Jul 28th, 2011Environment, New York City, News

Leif Percifeld ventures into these city sewers to install his DontFlushMe sensors

Last week, Harlem residents held their noses as millions of gallons of untreated sewage water flowed straight into the Harlem and Hudson rivers because of a sewage plant fire. On the hottest day of the year, precious beaches and water areas were off limits, too toxic to swim in, as a repair team took shifts working in the heat to fix the plant.

But the crisis was more than just an isolated incident; it was symptomatic of a larger, structural problem in the way New York City – home to 8.5 million people – deals with its residents’ liquid waste.

Each year, 27 billion gallons of raw sewage are dumped into the New York City harbor, making sewage, or more specifically, the city’s inability to process waste water, the largest source of water pollution in the city. This dumping is caused by Combined Sewer Overflows that occur when the sewer system becomes overloaded by heavy rain on top of normal sewage flows. Overburdened city infrastructure is simply not capable of handing so much water.

The solution to this problem may lie in what is known as “green infrastructure.” Green infrastructure, according to  the Department of Environmental Protection and PlaNYC, the city’s sustainability initiative, includes “advanced tree pits, porous pavements and streets, green and blue roofs.” It is essentially anything that is built in to the city’s currently existing infrastructure that makes systems, like sewage collection and treatment, run more smoothly.

Large-scale, industrial solutions, such as 50-million underground sewage storage tanks are simply not affordable given New York City’s budget constraints, and the return on investment for these tanks is diminishing rather than growing according to PlaNYC. Therefore, other solutions must be taken seriously.

With green infrastructure, the city aims to reduce Combined Sewage Outflows by “manag[ing] runoff from 10% of the impervious surfaces in combined sewer watersheds through detention and infiltration source controls.” One tangible way to do this — the MillionTreesNYC campaign, which is planting trees throughout the city not only to provide shade, but also to create more treebeds that absorb rainwater.

But to many sustainability activists, the city’s green infrastructure plan is just a stop-gap measure: well-intentioned but too centralized and bureaucratic.

The Hudson River will not be fit for swimming, kayaking, wind surfing, etc. now through Sunday.
S.W.I.M. Coalition

The Stormwater Infrastructure Matters (S.W.I.M.) coalition’s approach differs from the city’s. The coalition views stormwater as a resource, rather than a waste. They want to improve water quality through “natural, sustainable stormwater management practices in our neighborhoods,” according to their website.  They have over seventy member organizations working on infrastructural water issues in New York City.

After the North River sewage plant crisis last week, S.W.I.M. released news that the level of pollution in the Hudson River was much higher than the Department of Environmental Protection (DEP) had announced.

Riverkeeper is one of our member organizations,” explained Kate Zidar, the coordinator of S.W.I.M. “They sampled in the middle of the river and near the shoreline; they did a comparative grid. It’s not totally clear to me how DEP tests; typically they test midstream.  Riverkeeper found the pollution because they looked for it.”

What does this say about the DEP’s efforts to fulfill their responsibilities? “Both the testing and the notification that is based on that testing is insufficient. It doesn’t meet their required duties,” said Zidar.

Zidar is critical of the DEP’s plans for stormwater management as well. “The DEP is kind of creating their own definition of green infrastructure, which is confusing for people who have been in this field longer than they have,” she said. “They are using the term ‘green infrastructure’ to refer to what’s really stormwater detention.”

Detention refers to a process by which stormwater is held and then later released, decreasing the volume of water in the system, but retention, by contrast, is when water is retained and utilized. Retention, not detention, is what green infrastructure is based on, according to Zidar and others in S.W.I.M.’s network.

“There are major flaws in the [city's] plan,” said Zidar. “We’re trying to make this better.”

In addition to the S.W.I.M. coalition, individual sustainability activists are taking matters into their own hands. One technology designer, Leif Percifeld, has invented a way for the NYC sewer system to “talk back” to New Yorkers, alerting them to storm events and system overflows.

Using Open Source coding and software, Percifeld made a sensor that can detect rising water levels and send text messages warning recipients not to use water at home. His next step is getting into the city’s sewers to install the sensors – no easy task, given that he’s doing it illegally and undercover. With the help of a canoe, a flashlight, and some mapping software, however, he is determined to make it happen. Anyone can sign up for the alerts through the Don’t Flush Me website.

Can citizen science solve the problem of Combined Sewage Outflows?

Percifeld is acting to solve this problem as a citizen scientist, tackling a citywide infrastructural problem through grassroots means: crowdfunding on a website to pay for materials, developing the technology on his own, and entering sewers without authorization.

Another citizen scientist team, Seeing Green, is embarking on a year-long research project to evaluate the potential of urban farms to become part of a city’s green infrastructure. Like Percifeld, Tyler Caruso and Erik Facteau are working at the grassroots level, collaborating with people in their social network and employing their own know-how and resources to tackle the problem of burdened water systems. Caruso and Facteau would like for their research to nudge city officials into providing further support for urban agriculture.

Cleaning up the city’s waterways is a dirty job. But solutions are evolving from all levels – official citywide plans and grassroots, collaborative efforts amongst concerned citizens. Moving forward, it will be vital that the lines of communication between all these actors are kept open so that affordable, sustainable solutions can go into effect as quickly as possible.

9 Responses

  1. Erin Barnes says:

    Leif is raising money for Don’t Flush Me on ioby. You can help him help us help our sewers by donating $5 here:

  2. [...] A dirty job, but solutions do exist: Green infrastructure's potential for New … The coalition views stormwater as a resource, rather than a waste. They want to improve water quality through “natural, sustainable stormwater management practices in our neighborhoods,” according to their website. They have over seventy member … Read more on Dowser [...]

  3. Great post. You can also view the Combined Sewer Outfall locations on the OASISnyc maps. Here’s a sample: you can zoom in on each one, click it to open a bird’s eye aerial view, and rotate the view north, south, east, west for the best angle. Here’s an image from the Bronx:

    Btw, last year the blog had a nice post about different online maps of the city’s CSOs:

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  5. [...] One of the attractions of moving to a smaller town was the chance to get my kids involved in Scouting. Which isn’t to say they don’t have Scouts in New York City. They do. But what kid deserves to learn how to canoe amid 27 billion gallons of raw sewage? [...]

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