Nitrogen Reduction Project Improves the Health of the East River and Long Island Sound

As any NYLCV member who has been following our work on the Community Preservation Fund in Long Island knows, nitrogen overload is at the top of the list of environmental crises plaguing our waterways. Nitrogen is a naturally occurring element that is found in food and other organic materials and is present in wastewater when it enters the treatment plants. Because nitrogen poses no threat to human health, wastewater treatment plants were not originally designed to remove it from the treated water before discharging into a receiving waterbody.

Recent scientific research — led by Christopher Gobler at Stony Brook — has made a connection between excessive algae growth and high levels of nitrogen. Algae blooms reduce levels of dissolved oxygen in the water, especially in warmer months, in turn contributing to the disturbing spate of massive fish die-offs and other negative consequences for the ecological health of our waterways.

Last week, the New York City Department of Environmental Protection announced that, following a $1 billion investment in upgrades at four wastewater treatment plants, the amount of nitrogen being discharged into the Upper East River has been reduced by more than 60 percent. These significant upgrades will improve the health of the marine ecosystems in the East River, Long Island Sound and New York Harbor.

In total, New York City produces, and DEP collects and treats, an average of 1.3 billion gallons of wastewater each day. The wastewater travels through the City’s 7,500 mile sewer system until it reaches one of 14 wastewater treatment plants, where it is treated to federal and New York State water quality standards in accordance with the Clean Water Act before it is discharged into local waterways.

As part of an agreement with the New York State Department of Environmental Conservation (DEC) and then New York State Attorney General Eliot Spitzer in 2006, DEP committed to reducing the combined nitrogen discharges from its wastewater treatment plants located along the East River by 58.5 percent by January 2017. This announcement is the culmination of that agreement as by September of last year, nitrogen discharges from New York City wastewater treatment plants to the East River had been reduced by approximately 61 percent, surpassing the target reduction.

The largest capital investments within the $1 billion are:
$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
$161 million at the Bowery Bay Wastewater Treatment Plant

The nitrogen removal technology, which converts the organic nitrogen present in wastewater into inert nitrogen gas that is released harmlessly into the atmosphere, required significant upgrades to much of the plants’ supporting infrastructure, explaining the price tag. In addition to reducing the amount of nitrogen discharged from the plant, this investment will ensure that the facilities remain in a state of good repair for decades to come.