The Flushing River is one of several waterways in the city polluted by combined sewage overflows.


The Flushing River is one of several waterways in the city polluted by combined sewage overflows.

The recent collaborative series between City Limits and WNYC about our city’s water system and the challenges in making our waterways swimmable was very informative.

Especially striking, and a core element of the work of the Stormwater Infrastructure Matters (S.W.I.M.) Coalition’s members, is the predicament the city faces when our combined sewer system is overwhelmed by rain storms or melting snow, which together make up stormwater runoff. Over the course of any given year, billions of gallons of untreated sewage mixed with stormwater runoff are discharged directly into our waterways.

Aside from the city-wide solutions advocates like the SWIM Coalition are calling for (i.e. green infrastructure on public, commercial, and private property; green infrastructure incentive programs for private property owners, and water rate restructuring), the solution to stormwater pollution starts with you. Stewardship of the waterways, which belong to all of us, needs to be a joint effort.

What can you do to address this problem?

One of the first things that can be done is to reduce indoor water consumption when it’s raining and when snow is melting. One recent WNYC/City Limits analysis put it even more simply: Don’t flush the toilet during heavy rains. [Editor’s Note: That radio story further noted that it was also best to avoid doing laundry or taking showers during heavy rains. And City Limits published this broader list of ways to reduce water consumption.]

While not flushing during a rain storm or snow melt is an important action to take,and everyone should try to remember to do it, the concern is that this action would only be effective in the combined sewer areas (“CSOs”) of the city, and only if enough people participate—a feat both unrealistic and impossible to enforce. Approximately 60 percent of the city is in the combined sewer area, the other 40 percent is either on a separate sewer system or not on any sewer system (see a map of the city’s sewer drainage areas here).

Here is a short list of other at-home solutions for reducing the amount of pollutants that enter our waterways:

• Don’t take long showers, don’t run the dishwasher, and don’t laundry during a heavy rain or snowmelt (here is a link to explanations about why this is helpful);
• Don’t pour harmful detergents, chemicals or oils down your sink or storm drains (here is a link to household drop-off sites around NYC);
• Pick up any trash that you might see lying around on streets or sidewalks (keeping it from clogging stormwater systems);
• Sweep, don’t hose down, driveways, sidewalks, gutters, and patios;
• Pick up after your pet (pet waste is raw sewage and can be a leading pollutant in separate sewer areas); and
• Report a potential pollution violation when you see it (Riverkeeper has a great reporting site).

Generally, here is a link to information about ways to get involved and why it’s important to clean up urban waterways, and here is a list of more simple ways you can minimize your water impact.

Why is it important to help keep our waterways clean?

The beaches and waterways of New York City are used recreationally (for boating, swimming, and fishing) as well as for education and for food. Clean waters, therefore, protect the economy by protecting public health. By making water uses safer, fewer surfers, kayakers, fishermen and school children (on trips to the water’s edge) will get ill from contact with the water, and fewer families will be endangered by eating fish and crabs out of our polluted waterways.


Given the very real public health dangers that come with the environmental risks of sewage pollution, it is imperative to clean – and keep clean – the city’s waterways. Revitalized waterways would not only mitigate these health risks and promote the recreational water-use economy, they enhance citizens’ connections to open spaces and spur local waterfront economic growth.

Where can you start?

In short, it’s a big problem, bigger than not flushing when it’s raining. In order to achieve these bigger fixes, a broader array of comprehensive solutions should be implemented.

In many cities, private property owners can implement sustainable stormwater management solutions on their properties such as green roofs, rain gardens, rain water catchment devices, collectively referred to as green infrastructure, and receive money from the city to cover the costs.

NYC has a Green Infrastructure Grant program for private properties. More information on how the program works can be found here. Simple alterations on a private property can have a significant impact on how much water runs off a property and into the city sewer system.

NYC also has a green-roof tax abatement incentive but it would certainly help to have other incentives and discounts for property owners to manage stormwater runoff on-site and implement water conservation measures. The grant and the tax abatement programs are both great first steps. Here is a link to a set of five incentive program examples that other cities are implementing.

What is the city doing?

In addition to the actions that private property owners can take,public works programs on a large scale, are also necessary. One of the larger-scale ways that the city is reducing sewer overflows is by installing thousands of small public right-of-way bioswales (street-side tree pits designed to capture and retain the stormwater that runs along the curb during rains). The city is currently installing bioswales in several of the neighborhoods with the highest level of combined sewer overflows (see a map of priority areas here).

The city’s Department of Environmental Protection (“DEP”) recently issued a report on how well these bioswales are performing, wherein the agency noted that pilot sites are capturing and storing more stormwater runoff than originally anticipated. If you’d like to get involved in caring for a bioswale in your neighborhood, click here.)

Even with advancement in bioswales, the city needs an “all-of-the-above” approach to reducing water pollution. Green infrastructure on commercial properties would help support the public bioswale and tree planting programs in the city. Recently, the Natural Resources Defense Council released a study on the benefits of green infrastructure on commercial properties.

In addition to green infrastructure programs, the city is also implementing large-scale sewer system upgrades, often referred to as grey infrastructure. Here is a link to information about the city’s grey infrastructure investments. Grey infrastructure tends to cost more but it can make a larger single-project reduction in pollution; green infrastructure is more cost effective, but often limited in how much water pollution each site can capture.

What about the costs?

Unlike New York City, hundreds of the largest cities across the nation have restructured their water rates to charge property owners according to the actual amount of stormwater runoff their properties generate. This approach gives cities the ability to pay for infrastructure upgrades and innovative storm water management programs with funds generated by those who impact the water systems the most. In New York, however, we’re burdened by an old-model system that charges the largest stormwater polluters only a fraction of what they would pay elsewhere.

Currently, NYC’s billing structure for municipal water and sewer cost is based on two charges:

1. A water charge for metered potable (water flowing into a property for showers, toilets, sinks, dishwashers, washing machines, hoses, sprinklers) water use.

2. A sewer charge for non-metered wastewater (water flowing out of a property and into the city’s sewer system) and stormwater (rain water and snow melt that flows off the rooftop, parking lot, and other non-porous areas of a property and into the city’s sewer system).

The formula used to calculate the sewer charge is 159 percent of the metered water charge across the board for all property types city-wide. At first glance, this system might appear to make sense – you pay for water coming in, and water going out (more for the water going out, because sewage needs to be treated).

While relating the wastewater portion of the charge to the metered potable water usage makes sense, the amount of stormwater generated from a property is totally unrelated to the amount of potable water used: rather, it is related to the amount of impervious surface (a surface that does not absorb water, i.e. roof, driveway, sidewalk, patio, or parking lot ) on the property.

The result? This method of calculating stormwater runoff leads to many households overpaying and other ratepayers (especially industrial and low-rise commercial properties) to underpay. This means that a big box store using about the same amount of water as a two-family home pays the same sewer charge as a two-family home, despite having a much, much larger stormwater footprint. This inequality has been addressed in other cities, but not yet here.

The Stormwater Infrastructure Matters (S.W.I.M.) Coalition is currently calling on the city to conduct an in-depth feasibility study (building off of an initial study from 2010) combined with the formation of a Citizens Advisory Committee composed of citywide stakeholders, to examine the potential impacts of a restructured water rate system. Members of the S.W.I.M. Coalition Steering Committee have met with city officials and City Council members and written letters to the Water Board requesting the feasibility study. We plan to continue our efforts and to join the efforts of other organizations in the city in order to see the that the study is implemented soon.

In the face of sea-level rise, flooding, and climate change-induced storm intensification, the greater New York region faces a significant stormwater management and water quality challenge in the years ahead. The capital improvements needed to address sewer overflows and stormwater pollution from city sewers will take many years—perhaps decades—to implement. Citizens and government agencies will need to work together in an innovative and transparent manner to solve this pressing challenge; at home, as a city, and as stewards of our local waterways.

The Stormwater Infrastructure Matters (S.W.I.M.) Coalition is a group of 70 member organizations dedicated to ensuring swimmable and fishable waters in New York City. For more information on the topic of green infrastructure programs, policies, upcoming city plans for addressing sewer overflows in specific waterways and the actions we are taking to ensure swimmable fishable water quality around the city, please visit the S.W.I.M. Coalition website: or contact us at

To get more information about local water quality after a heavy rain and whether it is safe to swim, boat, surf, or fish, you can sign up to receive alerts directly to your phone, email, or text via the NY-Alert system. Step by step instructions and guidance videos are available on the Sewage Pollution Right to Know webpage.