Green Infrastructure could reduce New York’s sewer overflow


Image by Robert Jones from Pixabay

Kayaks on New York’s Hudson River

For the 8.5 million people living in the city of New York, access to safe and accessible waterways, particularly in the city’s hot summers, is a pipe-dream.

Every year, more than 25 billion gallons of combined sewer overflow pour into the harbour, polluting the waters so they aren’t safe to fish or swim in after intense rain.

The City has introduced its final and largest Long Term Control Plan (LTCP) to address the problem – but critics say it does not go far enough.

Those 25 billion gallons are expected to rise as more frequent and intensified downpours in a changing New York climate put even more strain on the city’s treatment facilities.

Environmental conservation organization Save the Sound condemned the Citywide/Open Waters LTCP in a March press release.

The group argues that the plan developed by the Department of Environmental Protection (DEP) does not comply with updated water quality guidelines and fails to protect the environment and public health.

Why it happens

Combined sewage and stormwater overflows occur every time the city’s sewage treatment facilities reach maximum capacity.

To prevent toilets from becoming gruesome fountains of sewage — as in the experience of 100 homes in Queens, the excess wastewater is diverted into waterways all over the five boroughs making them unsafe to even touch.

“Just about every time it rains as little as a quarter, even sometimes a tenth of an inch, you’re having these overflows. So that means on half of the days, somewhere in New York City, there is some sewage outfall overflowing with raw sewage,” said Mike Dulong, Senior Attorney for the water advocacy non-profit Riverkeeper.

The New York Harbour has seen an astounding 80 per cent reduction in combined sewer outfall, despite growing population pressures, and its water quality has significantly improved in the last century.

However, smaller inlets of water that are open to the public continue to be unsafe for recreational swimming and fail to meet the standards of the Clean Water Act.

Planning for the future

In 2012, New York State agreed to roll out a series of long-term plans that would help in the reduction of sewer overflow events and intensity.

Ten of the plans are waterbody-specific and the last one is meant to encompass several of the city’s major bodies of water including the Hudson River, Harlem River, East River, Upper and Lower New York Bay, and part of the Long Island Sound.

But despite the fanfare, the Citywide/Open Waters LTCP will merely reduce two to four per cent of the annual CSO pollution – which contains 11 billion gallons of raw sewage. It won’t improve any of the outfall locations in the Bronx.

According to Save the Sound, the plan offers little investment in the East River and the western portion of the Long Island Sound — home to a large number of beaches.

“This plan really is a drop in the bucket, minuscule for all those waters which are the majority of the waters in New York City – and they receive the majority of the sewage,” said Dulong regarding the proposed LTCP.

“Some of them will reduce the amount of sewage going into waterways significantly. None of them, not a single one, is going to make those waters fishable and swimmable.”

“I’ve actually had two regatta races cancelled due to how filthy the water was,” said Bronx resident Aleeyah Marrero, who’s rowed for ten years with Row New York. “There have been multiple instances of when the water became a health concern of mine. Specifically, at times while rowing the water would tend to splash on either me or my teammates and whenever the water would splash on me, my skin would sometimes have an allergic reaction to it.”

Widespread waterways

There are 800 outfalls across the state of New York, 460 of which dot the coast of the five boroughs, posing a threat to public health. The state’s Department of Environmental Conservation (DEC) advises the public to avoid recreational boating, swimming, and fishing near combined sewer outfall sites in the event of rain due to possible pollutants and illness-causing bacteria in the water following the discharge of untreated sewage.

Urban waters are the most polluted but have the greatest opportunity for improvement and the impact goes a long way, said Dulong.

“When you do clean up a waterway, that starts to mean that you can use that waterway as a park, you can go and kayak on it, it’s a calm peaceful place to get out on the water and it’s a clean place to get on the water.”

The City’s plan also does not consider the 4 to 11% predicted increase in annual rainfall by 2050.

Several environmental organizations have argued the plan doesn’t include enough green infrastructure – even though this would be a cost-effective approach. Green infrastructure would help make use of the city’s empty rooftops and lots by introducing vegetated roofs, more rain gardens, and porous pavement lined with street trees that would help trap stormwater before it enters the drains.

Greening the city

In the fight to make surrounding water bodies New Yorkers’ backyard, finding space for green infrastructure has been one of the biggest challenges in addition to the concrete jungle already lagging behind in green space per person.

“It’s hard to create or build on land, a big enough green area or big enough porous or permeable area to capture all the stormwater because so much of urban land has been built already or dedicated to some other use or activity,” said Carter Craft, urban planner and Senior Economic Officer at the Dutch Consulate in New York City, on the city’s neglect of green infrastructure.

To achieve a healthier urban environment, Craft suggested empowering homeowners and property owners across the city to make small yet significant investments in green infrastructure such as rain gardens and rain barrels on their own property.

Craft’s own apartment building located on the other side of the Hudson has invested in two rain barrels which he estimates retain 110 gallons of rainwater from entering the sewer system every rainstorm.

The city’s separate green infrastructure program is currently behind on meeting its 2030 goal to capture an annual 1.67 billion gallons of combined sewer overflow. According to Dulong, it’s not incorporating it into the citywide LTCP, but it should be. “It should be evaluating all of the opportunity for green infrastructure in every single waterway.”

Many communities will see no improvements in the quality of nearby waterways based on the citywide plan whose approval has been postponed to May 30, 2020 due to the coronavirus.

Groups like Riverkeeper and Save the Sound are hoping to see pressure put on city officials to adopt more effective plans.

“We need to find ways to stop treating rainwater like wastewater and capture it and use it and be a steward of it to help spur other things and support other activities like urban agriculture,” said Craft.

Investing in additional green infrastructure to clean up the harbour means creating secure green jobs, addressing issues such as food security, and the urban heat island effect, he concludes.