Excess nitrogen is poisoning Long Island’s coastal vegetation, making the region more susceptible to the impacts of flooding and storms. A Suffolk county executive described the problem as “the most critical issue our community has faced in a generation,” and all levels of government are now working on a multi-pronged solution.

Nitrogen is a “natural part” of aquatic ecosystems, and it is also the “most abundant element in the air we breathe,” says the U.S. Environmental Protection Agency.

But excess nitrogen in air and water causes “nutrient pollution,” which the EPA describes as “one of America’s most widespread, costly and challenging environmental problems.

One visible sign of nitrogen’s local impact are the algae “blooms” seen with more frequency off the Long Island coast.

Yesterday, state regulators, some Long Island elected officials, and environmental and economic groups met to examine the impact of excess nitrogen in the first of three public meetings. The discussion-in Nassau County’s Legislative Chambers- focused in part on how to reduce high nitrogen levels in the back-bay area north of Long Beach Island.

Long Island’s Wastewater Challenge

The objective of the three meetings, said state Department of Environmental Conservation commissioner Joseph Martens in a press release, is “to build a plan that will address longstanding wastewater issues in Nassau and Suffolk counties.”

[pullquote]68 percent of the total nitrogen entering Long Island’s Great South Bay comes from wastewater, “including wastewater from septic systems and sewage effluent discharges.”[/pullquote]

The state says that 68 percent of the total nitrogen entering Long Island’s Great South Bay, for example, comes from wastewater, “including wastewater from septic systems and sewage effluent discharges.”

Because nitrogen is not a pathogen and does not pose a threat to human health, local treatment facilities were not typically designed to remove nitrogen as they processed wastewater. The nitrogen-heavy wastewater is then released into local waterways after treatment.

Another challenge is that some sections of Long Island rely heavily on individual septic systems, which also do not remove nitrogen. Approximately 70 percent of homes and businesses in Suffolk County, for example, are not served by sewers.

A More Vulnerable Coastline

Photo credit: National Park Service / Diane Abell
Photo credit: National Park Service / Diane Abell

Of particular concern to state and local officials is the impact of excess nitrogen on Long Island’s marshes, which are a “critical line of defense against severe storms and flooding.”

According to the state, “coastal marshes and their vegetation provide a natural infrastructure that calms storm surges and damaging waves along Long Island’s south shore bays.” Nitrogen pollution is “a threat to these marshes, causing the grasses to grow taller, but produce fewer and less dense roots, which destabilizes the marsh grasses”.

A white paper released by the DEC last week cites specific examples of significant marsh loss over the past several decades on Long Island, including marshes in the Great South Bay.

From 1974-2001, “there was an 18-36 percent loss in tidal wetlands in the Great South Bay as a result of factors including excess nitrogen entering the watershed,” the state found.

Reducing Nitrogen Levels Across the Region

A number of strategies are being examined to help reduce nitrogen levels. In Suffolk County, the state is considering financing options for septic system replacements and retrofits that it would offer in partnership with the county.

The state DEC and Suffolk County are also rolling out a $6 million plan for testing and implementation of nitrogen treatment pilot projects at individual homes and small subdivisions that are not easily reachable by sewer lines.

[pullquote]Protecting the Bay is critical as it is a “regionally important fish, wildlife and plant habitat complex.”[/pullquote]

Upgrading wastewater treatment plants is another solution.

New York City’s Department of Environmental Protection announced last week that it had completed a $230 million upgrade to a local wastewater treatment plant that “will reduce the amount of nitrogen discharged from the plant into the Upper East River and Long Island Sound by more than 3,500 pounds per day, or nearly 1.3 million pounds each year.”

The city says that the upgrade to the Tallman Island Wastewater Treatment Plant will allow it to convert the organic nitrogen present in wastewater into “inert nitrogen gas that can then be released harmlessly into the atmosphere before the treated water is released into the surrounding waterways.”

Loss of protective marshland and excess nitrogen levels are an issue for New York City too. The state says that Jamaica Bay has seen “dramatic losses in intertidal marshes.” Protecting the Bay is critical as it is a “regionally important fish, wildlife and plant habitat complex.”

In response, New York City has invested $460 million in nitrogen reduction upgrades at the Jamaica Bay and 26th Ward Treatment Plants, which discharge into Jamaica Bay.

The city says it has invested more than $1.5 billion to reduce nitrogen discharges from its wastewater treatment plants over the last decade.

How Can Long Islanders Participate in Clean Water Planning?

Crafting a strategy to reduce nitrogen levels is part of a broader review by the Cuomo administration of Long Island’s clean water infrastructure needs. Long Island’s sole source aquifer serves as the water supply for 2.5 million residents.

The Governor’s office states that they are committed to providing “additional protections for Long Island’s groundwater resources,” along with increasing resiliency against future storms, and improving water quality.

A second meeting on “coastal resiliency and clean water infrastructure” will be held on May 19 at SUNY Stony Brook and will feature presentations from researchers. The third meeting will be held May 28 in Suffolk County. The public will have the opportunity to make oral comments during the evening portion of the May 28 meeting.

The public can submit written comments at all three meetings or by emailing liwaterquality@gw.dec.state.ny.us.

A final meeting in June will feature recommendations to Governor Cuomo on how to address wastewater and septic problems “to make Long Island more resilient.”