Long Island Water Quality

What Is Nitrogen Pollution?

Water Questions What is nitrogen pollution?

Growing Awry

Nitrogen makes plants grow. But too much of a good thing is a bad thing. When too much nitrogen flows to our bays, fast-growing plants out-compete and kill slower-growing beneficial plants. Decaying plants use up oxygen, which kills fish and other marine life. Algae blooms such as brown tide, rust tide, and the macro-algae called Ulva, (AKA Sea lettuce) are examples we now see around Long Island.

Poisonous for People and Wildlife

The red tide algae Alexandrium produces a powerful neurotoxin that accumulates in filter feeding shellfish that can poison the people or wildlife that eat them. Toxic algae are increasingly occurring in Long Island's bays and harbors.

More costly water quality sampling and enforcement by government to open and close shellfishing areas is becoming the norm. But wildlife can't read the no-shellfishing signs and the results can be devastating.

In Long Island, nitrogen pollution from outdated septic systems has resulted in algae blooms and rust tides.
Nitrogen Pollution In Long Island, nitrogen pollution from outdated septic systems has resulted in algae blooms and rust tides. © USCG

Unsafe for Contact

Long Island's ponds and lakes also suffer from nitrogen pollution. In addition to fueling infestations of invasive plants, such as cabomba, high nitrogen levels are also increasing the growth and toxicity of killer blue-green algae. Blue-green algae are toxic to fish, wildlife, livestock, pets, and people. In 2015 Suffolk County issued 'no contact' advisories for 14 lakes and ponds due to this threat.

Explore Local Stories About Water Quality

We're Oyster Farmers
Montauk
An oyster farm with 1 million oysters can filter 50 million gallons of water per day, making them a critical piece in protecting Long Island's water quality from nitrogen pollution
Southwest Nassau County
Jim's Solution
A Freeport junkman Jim Ruocco has witnessed what happens when 50 million gallons per day of minimally treated sewage effluent are discharged into a poorly flushed estuary.
Answers & Solutions
Huntington
As a fishermen and scientist, Carl LoBue ponders what our successors will think about the decisions we make today, and how those decisions will impact the island’s fishing future.
Generations
Shelter Island
See how Long Island’s smallest township is a microcosm of the region-wide water quality problem.
On Display
Bellport
When the new Great South Bay inlet created by superstorm Sandy opened up, it formed an 8-mile undeveloped stretch of Fire Island called the Otis Pike High Dunes Wilderness Area.
It's Imperative
Mastic Beach
Mayor Maura Sperry talks about how water quality affects one of Long Island’s most flood-prone communities.
Something Lost
Oakdale
George Remmer, commercial fisherman, restaurant owner, and college professor, laments the changes he has seen around Great River, Grand Canal and Great South Bay.
Collapse of a Legacy
North Sea
Howard Pickerel has hand-built 600 boats in his backyard. Pickerel boats were at one time the backbone of Long Island’s shellfishing industry.
A New Perspective
Springs
Evelyn O'Doherty is a year-round stand-up paddleboard racer, paddler, surfer and yoga teacher who lives in East Hampton.
On Georgica Pond
Wainscott
Even Long Island’s most bucolic communities are not immune to the effects of nitrogen pollution.
A Chef's Connection
Greenport
Forty years ago Bruce Bollman had a vision that Long Island’s North Fork would become a destination calling for gourmet artisanal eateries.