When “number two” is your order of business, nitrogen is one of the products you produce—and it’s a problem.
The element travels to your local sewage facility and out into the waterways to which that facility discharges treated water. There, nitrogen helps plants grow. Then those plants die. When they die and decompose, the process sucks oxygen out of the water. Fish that need that oxygen either swim away or, if the oxygen depletion happens too fast, die. This area of the water becomes known as a dead zone.
Twenty years ago, Long Island Sound, the body of water that defines this area of the Eastern Seaboard, had 200 square miles that were frequently hypoxic (meaning “lack of oxygen”) dead zones. Today, it has about 95 square miles that are often dead.
That’s a remarkable recovery, and it’s largely due to public policy decisions and government investments. Now advocates want New York City to aim for an even deeper recovery of the Sound.
Long Island Sound is a 110-mile-long body of water running from the East River to the northeastern tip of Long Island. Its watershed runs to the Canadian border, encompassing parts of Vermont, New Hampshire, Massachusetts, Rhode Island and Connecticut as well as the city. The nitrogen in its waters comes from several different sources, including the atmosphere, septic tanks and stormwater runoff. But sewage plants represent the largest source. And since New York City is the biggest population center on the Sound, most of the sewage issues and dead zones occur at the western end of the Sound.
In 2001, the city and Connecticut signed a deal with the Environmental Protection Agency to reduce nitrogen releases into the sound. The city committed to a 58.5 percent reduction in nitrogen by January 2017. Over 16 years, the city spent more than a billion dollars–$277 million at the Hunts Point Wastewater Treatment Plant, $388 million at the Wards Island Wastewater Treatment Plant, $209 million at the Tallman Island Wastewater Treatment Plant and $161 million at the Bowery Bay Wastewater Treatment Plant—in pursuit of that goal. In January, DEP reported that it had achieved 61 percent reduction.
“You can see the improvement. It’s getting better. This is proof positive that when we invest in wastewater treatment we get clean water as a dividend,” Tracy Brown, executive director of Save Our Sound, said at a City Hall press conference on Thursday. “We’re not done yet.”
Save Our Sound is pushing for the city to aim for a 70 percent reduction.
“Historically, hypoxia didn’t exist in Long Island Sound,” said Jamie Vaudrey, a professor with the Department of Marine Sciences at the University of Connecticut. In the 1920s, pockets of hypoxia were only detected in the East River, which is only 11 square miles. “We still have a long way to go to get back to the waters that we want as residents.”
There’s more than one rationale for the push. While federal law demands that waterways be cleaned up to be swimmable and fishable, there is also an economic stake: According to Michele Kumi Baer, from the New York Community Trust’s Thriving Communities program, $17 billion to $37 billion in annual economic activity is linked to the Sound. “We need clean water to sustain our lives, our cultures, our economy and our ecosystem,” she said.
What’s more, other environmental pressures are building. The city’s population is growing, meaning more nitrogen coming down the sewer pipes. Climate change is boosting the temperature and acidity of the water, exacerbating the damage done by nitrogen.
Nitrogen is not the city’s only worry. It has other water issues to deal with, too—like combined sewage overflows or CSOs and polluted stormwater runoff.
Alex Herzan from Guardians of Flushing Bay—a member of a dragon-boat racing team that practices there—noted the potential of the city’s waterways. The bay, she noted, “is kind of incredible in the middle of this industrial place by the airport.” Racers (in the case of Herzan’s team, all cancer survivors) see an array of birds and fish as they exercise on the blue surface.
But they also see reminders of the city’s habit of polluting the water. “We see dead rats, dead fish—all sorts of debris,” Herzan said. The city is hosting an annual public hearing on CSOs Wednesday night.
Getting to 70 percent reduction of nitrogen could mean more technological upgrades at the sewage plants, including two (Newtown Creek and Red Hook) that were not part of the 2001 nitrogen pledge but also drain into the East River.
It could also mean more expensive and elaborate fixes like piping the release water to the ocean to increase the likelihood that nitrogen will be diluted before it causes damage, according to Vaudrey. One barrier the city will face is the availability of land: tanks of nitrogen-eating algae and other forms of nitrogen-diverting technology take space that is a premium in the city.
Other cities also contribute nitrogen to the Sound, and while New York City has exceeded its commitment under the 2001 agreement, it’s not clear that their counterparts have kept up their end of the deal.
“New York City has invested more than $1 billion to meet nitrogen reduction targets and we look forward to working with our regional partners in Connecticut, Westchester and Long Island as they meet their reduction commitments to restore the health and ecology of Long Island Sound,” DEP said in a statement.