STATEN ISLAND, N.Y. — The New York City Health Department advises residents to avoid swimming at three Staten Island Beaches as of Saturday morning.
South Beach, Midland Beach and Cedar Grove were all slapped with water quality advisories by the department. These warnings are issued when there is either heavy rainfall, when water tests show unsafe levels of bacteria, or when a survey finds pollution, such as garbage, medical waste, toxic chemicals, oil, sewage, or wastewater, according to the Health Department.
According to New York State Sanitary code and New York City health code, a single sample of saline water can’t have more than 104 enterococci bacteria per 100 milliliters of water. For freshwater, the limit is 61 enterococci per 100 milliliters. Also, if the water is tested five or more times over 30 days, the average must be 35 or fewer enterococci per 100 milliliters in saltwater, and 33 or fewer per 100 milliliters in freshwater.
The most recent water quality tests taken at all three beaches was on Tuesday, May 27.
At South Beach, the 30-day geometric mean was 37 MPN per 100 milliliters, exceeding Department of Health limit of 35 MPN. The single-day test on Tuesday measured 10 MPN per 100 milliliters. “MPN” means Most Probable Number; it is a way to estimate the concentration of bacteria in a water sample.
At Midland Beach, the 30-day geometric mean was the highest, at 156 MPN per 100 milliliters, while the single-day result reached 75 MPN per 100 milliliters.
For Cedar Grove, the 30-day geometric mean was 38 MPN per 100 milliliters, while the single-day result reached 74 MPN per 100 milliliters.
