Hunts Point — The New York City Department of Environmental Protection (DEP) has expanded its efforts to clean up the East River and Long Island Sound by reducing their nitrogen levels. Nitrogen buildup promotes excessive algae growth, which endangers fish and other organisms close to the base of the food chain, converting once thriving waterways into dead zones. DEP has been working to interrupt this cycle by reducing the amount of nitrogen discharged from three waste-water treatment plants in the Upper East River. Last week, the agency announced that it has begun taking similar steps at a fourth wastewater treatment plant, the Hunts Point Wastewater Treatment Plant in the Bronx. The agency estimates that their efforts at the four plants will reduce the nitrogen discharged from them by more than 52 percent.

Environmental activists across the city said the city’s wastewater treatment infrastructure – which is now more than 100 years old – will still require plenty more upgrades, but praised the agency for taking these steps. Some of the environmental advocacy groups applauded Mayor Bloomberg and the commissioner of the DEP, Cas Holloway, for crafting PlaNYC, which addresses waterway cleanup, and following through on promises to implement it.

But representatives of the Metropolitan Waterfront Alliance and Riverkeeper also said the agency's efforts are long overdue.

“The Clean Water Act was supposed to be enacted by 1985, so we’re 25 years late but we encourage progress whenever we see it,” said Roland Lewis, president and CEO of the Metropolitan Waterfront Alliance.

“These are requirements that their permits should have had a long time ago,” said Phillip Musegaas, Hudson River Program Director at Riverkeeper.

In a press release, Commissioner Holloway said DEP has been working to upgrade treatment plants for years. “Years of steady and committed work to improve our treatment plants have already had measurable effects," he said. Today, our harbor water quality is the best it has been in 100 years and New York City is now meeting monthly secondary treatment standards for the first time ever."

In a follow-up email, DEP Press Secretary Michael Saucier added: "Since 2002, DEP has invested over $17 billion in water quality projects. And those investments are paying off. This year, for the first time ever, New York City’s wastewater treatment plants are meeting monthly Clean Water Act standards for pollutant removal."

The city's efforts to reduce nitrogen in the East River and Long Island Sound are part of a $1 billion effort to do the same in multiple city waterways. DEP's goal is to reduce nitrogen discharges to all New York City waterways by more than 60,000 pounds per day. A project that aims to reduce nitrogen discharges into Jamaica Bay by 50 percent over the next 10 years began in June.

Most of the nitrogen in the East River and Long Island Sound come from the numerous wastewater treatment plants operated along those waterways by more than 12 municipalities. DEP is reducing the discharge from the Hunts Point plant by using chemical and biological systems to modify and upgrade wastewater treatment processes.

City waterways are cleaner now than in the 1980s, in part, because sewer and stormwater overflow into them much less frequently and when the overflows do occur now, they are 250 percent cleaner, Saucier said. But environmental advocates said they believe the overflows remain the biggest challenge facing New York City waterways. A 2008 study conducted by Riverkeeper called Sustainable Raindrops pins the amount of untreated sewage and stormwater draining into city waterways at 27 billion gallons per year.

“It’s a major pollution issue and it’s an ongoing problem, particularly for areas like the Harlem River, the East River and some of the side waterways like Newtown Creek and the Gowanus Canal,” Musegaas said. “The CSO (combined sewer overflow) pollution is particularly bad because those waterways don’t have the high flow that the Hudson has. The water’s more stagnant there so the pollution there really tends to build up, so those waterways can’t really support any life.”

Riverkeeper, the Metropolitan Waterfront Alliance and NRDC say the best and most cost-effective way to reduce overflows in the near future is to plant more trees, convert more asphalt to absorbent road surfacing materials, and install more rooftop gardens. These and other elements of "green infrastructure," would better absorb rain, thereby preventing its drainage into city sewer systems. Sustainable Raindrops, the 2008 Riverkeeper study, found that a $1,000 investment in ‘green infrastructure’ could decrease sewer overflows by 12,000 to 14,800 gallons.

DEP is trying to encourage the deployment of green infrastructure projects throughout the city and in July officials there awarded a total of $2.6 million to five projects they believe will work and be replicable city wide, Saucier said. The Metropolitan Waterfront Alliance, NRDC and Riverkeeper all said they would like to see the city adopt green infrastructure policies faster.

“My opinion is that they can be more aggressive with some of the pilot projects that they’ve undergone,” Lewis said.

“What needs to happen now is we need to implement these programs, you know, every time there’s a city transportation project, every time there’s a reconstruction project,” said Eric Goldstein, Senior Attorney at the Natural Resources Defense Council. “We need to find ways of encouraging [for example], parking lot owners to capture storm water runoff before it reaches the storm drains.”