Answer: No. As of 2018, there is an increase in beach closure and advisory days. While beach closures are linked to pathogen presence and abundance, the increasing number of days that beaches are closed or issued advisories (due to contaminants or rainfall) may be due to higher heavy precipitation events. A closed beach may not be a direct result of water quality impairments. Many beach managers in Connecticut and New York close beaches preemptively when high rainfall generates stormwater runoff that may contain animal waste, untreated sewage discharge or other contaminants.
Health departments sample coastal bathing waters to determine whether the water exceeds an acceptable level of 104 CFU (Colony Forming Units)/100mL for the indicator bacteria, Enterococcus.
Enterococcus may indicate the presence of pathogens that can lead to gastrointestinal illnesses (GI) among swimmers. Pathogens are disease-causing organisms, including bacteria and viruses.  More often, beach managers in Connecticut and New York close beaches preemptively when high rainfall generates stormwater runoff that may contain animal waste, untreated sewage discharge or other contaminants. As of 2025, there were 92 monitored beaches along Long Island Sound’s shoreline in New York and 41 monitored beaches in Connecticut. Yearly variations in closures are a product of rainfall patterns and incidents such as sewer-line ruptures.Â
This data is collected and reported by EPA’s BEACON 2.0 – Beach Advisory and Closing On-line Notification.
Beach closures and advisories serve as an indicator for pathogen presence and abundance. Each county along the coastal Sound is required to measure bacteria levels, especially following a rain event as runoff from impervious surfaces and stormwater play a major role in bacteria levels. For example, dry years (2015, 2016, 2020, and 2022) resulted in a lower beach closures and advisories whereas in wet years (2019, 2023, and 2024), higher rainfall can drive the number of closures and/or advisories (see Heavy Precipitation for more details). However, this past year (2025) was also a dry year but resulted in one of highest closures and advisories on record. Most of these closures and advisories are located in western Long Island Sound where there is less flushing from the Atlantic Ocean compared to the eastern Long Island Sound embayments. Therefore, the water and its contaminants have a higher residence time and take a longer time to be removed from the system.
Beaches are closed to protect swimmers from potential harm or illness caused by pathogens or other contamination. Closed beaches can also have an economic impact because they prevent people from being able to fully enjoy the Long Island Sound shoreline. In a recent study conducted by Yale (Ramsden et al. 2023), preemptive beach closures are important for towns and municipalities to consider implementing to better protect public health. Most counties in the Long Island Sound implement these preemptive beach closures and advisories to protect residents and visitors.Â
While beach closures and advisories serve as an important indicator for pathogen presence and abundance; recent years’ data tell us that with heavier rainfall events, this indicator may be more linked to changes in climate rather than changes in water quality conditions. The Long Island Sound Partnership believes it is important to track and report this data since it is highly relevant to not only environmental health, but public health.Â
Sign up to receive our newsletters and updates. Choose the topics that interest you most!
"*" indicates required fields