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Glossary


PhraseDescription
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BEACH ActThe Clean Water Act was madated for coastal states by the BEACH Act (The Beaches Environmental Assessment and Coastal Health Act) in 2000. The BEACH Act requires beach water quality testing and public notification. It also provides grants to participating states to implement their monitoring programs. States were to adopt the revised water quality standards for pathogens and pathogen indicators by April 2004.

New water quality standards required by the 2000 BEACH Act are currently being implemented at swimming beaches in NYC. These standards require the geometric mean standard of 35 Enterococcus bacteria per 100 ml of marine water (at least five samples are meant to be taken per month) and a single sample standard of 104 Enterococcus bacteria per 100 ml of water.

Beach AdvisoriesNew York City adopted this pre-emptive measure to advise against swimming in areas affected by elevated levels of bacteria due to CSO’s and stormwater runoff during and after periods of rainfall. The NYCDOHMH now tracks rainfall levels reported by NOAA. When rainfall exceeds pre-emptive standards, the department notifies the Parks Department (which operates the public beaches) and private beach operators.
Beach Closings in NYCFor a beach to be classified as open for bathing, the Enterococci geometric mean can not be above 35 Colony Forming Units (CFU) per 100 ml for five samples collected in a 30-day period, and sanitary and safety surveys, and the epidemiological history must be satisfactory.
BrackishHaving a somewhat salty taste, especially from containing a mixture of seawater and fresh water
Chlorophyll-aChlorophyll-a is a plant pigment whose concentration is used to estimate the amount of algae present in water in order to determine the biological productivity of a water body.
Clean Water ActPublic awareness and concern for controlling water pollution led to enactment of the Federal Water Pollution Control Act Amendments of 1972. As amended in 1977, this law became commonly known as the Clean Water Act. The Act established the basic structure for regulating discharges of pollutants into the waters of the United States.
Combined Sewer Overflows (CSOs)Combined sewer overflows (CSOs) are pipes designed to carry both stormwater runoff from streets after rainstorms, and raw sewage from residences, businesses and industries to sewage treatment plants. More than 70% (or 4800 miles) of New York City's 6000 miles of sewer system is combined with stormwater pipes.

This antiquiated system (starting from the 1600s) is prone to discharging a mixture of rainfall runoff and raw sewage into waterways during and immediately after rain. When it rains as little as one-tenth of an inch per hour, the volume of the combined wastewater becomes too great for the sewage treatment plants to handle (plants are designed to accommodate twice the dry weather flow). The flow is then diverted to outfall points that discharge the pollutants (raw sewage, garbage, and contaminated stormwater) into the nearest waterway. There over 700 discharge points in the New York Harbor: including about 450 in NYC; 250 in Jersey City and 26 in Yonkers. In a typical year NYC treatment plants capture only 70% of water discharge.

CSO retention tanks are being built around the city to capture CSO overflows for later treatment. One is operating in Jamaica Bay and others at Patagate Basin, Flushing and Alley Creek are being constructed.

CSOs are considered to be the largest source of microscopic disease causing organisms (pathogens) in the New York Harbor. Elevated bacterial levels associated with CSOs can lead to beach closures and contaminated shellfish. They are a major source of small floatables such as cigarette butts, syringes and tampon applicators. In addition, toxic substances from households and industry, such as paints, oils, solvents, cleaners, pesticides are flushed into the harbor in CSOs. Learn more.
CurrentGenerally, a horizontal movement of water. Currents may be classified as tidal and nontidal. Tidal currents are caused by gravitational interactions between the sun, moon, and earth, and are a part of the same general movement of the sea that is manifested in the vertical rise and fall, called tide. Nontidal currents include the permanent currents in the general circulatory systems of the sea as well as temporary currents arising from more pronounced meteorological variability.
DDTDDT or dichloro-diphenyl-trichloroethane is a pesticide developed in the 1940’s. It was banned for agricultural use in many countries in the 1970’s due to what many believe is a negative environmental impact.
DebrisDebris or “floatables” is street litter which ends up in the cities storm drains and sewers. Floatables are washed into waterways during rain. They contribute to beach closures, interfere with navigation, entangle wildlife and are ugly. 42% of the debris is plastics, 26% is paper and 26% is polystyrene.
DioxinDioxin is a general term that describes a group of hundreds of chemicals that are highly persistent in the environment. Dioxin is formed as an by-product of many industrial processes involving chlorine such as waste incineration, chemical and pesticide manufacturing and pulp and paper bleaching.
Dissolved MatterDissolved matter is a type of water pollutant and includes sewage, nutrients and pathogens derived from wastewater treatment plants and combined sewer overflows. Learn more
Dissolved OxygenDissolved oxygen in water is required by most aquatic species and its levels impact the health of aquatic organisms. New York State’s standards require that dissolved oxygen never drop below 3-5 parts per million (ppm) depending on the designated best use of the Harbor’s waters. Learn more
East RiverNot a river, but a narrow tidal strait which flows in both directions due to its reversing current. It 16 mi (26 km) long and 600-4,000 ft (183-1,219 m) wide, connecting Upper New York Bay and Long Island Sound, New York City, and separating the boroughs of Manhattan and the Bronx from Brooklyn and Queens. The East River is linked with the Hudson River at the northern end of Manhattan island by the Harlem River. Roosevelt (formerly known as Blackwell's Island, until 1921, and Welfare Island, until 1973), Wards, Randalls, Rikers, North Brother, and South Brother islands, all located in the East River, have city institutions, parks, and recreation areas. Roosevelt Island was developed as a residential area in the early 1970s. Hell Gate, at the junction of the Harlem and East rivers, was named for its treacherous currents and rocky reefs (now removed). Eight bridges, including the historic Brooklyn Bridge, span the river; subway, railroad, and vehicular tunnels pass beneath it.
EbbThe receding or outgoing tide; the period between high water and the succeeding low water.