Water Quality

Rivers, Lakes, and Estuaries               Water of Long Island Sound               Warming and Rising Waters                Clamming and Oystering              Drinking Water


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Climate Change Indicator



Coastal swimmers saw more beach actions* in 2023.

There were 220 beach action days for all 73 reporting coastal beaches in Connecticut in 2023. Of the 220 beach action days, which was approximately 21 percent greater than the previous ten-year average (181), 190 (86 percent) were closures and 30 (14 percent) were contamination advisories. Of the 220 beach action days, 54 percent were “preemptory actions” due to rainfall, while 46 percent were due to elevated levels of bacteria.42 Precipitation in the summer of 2023, which was approximately 50 percent greater than the previous 30-year average, and the resulting increase in combined sewer overflows, were likely the reasons for the increase in beach action days in 2023. The chart above displays both closings and advisories at Connecticut’s public coastal beaches since 2013, which from a water quality perspective are functional equivalents. The beach-specific advisories or closings are issued by the reporting state or local government entity.


Because the number of beaches varies by county, the Council utilizes a ratio of beach action days (closures and advisories) to the number of reporting beaches in each county to illustrate the relative impact that pollution has on coastal recreation waters. Typically, the western half of the coastline, which has more impervious surfaces, sees the most beach actions. 

Goal: The goal for keeping beaches open is to reduce the number of beach closings in half by 2035 from 2014, with the number for 2014 calculated using a five-year rolling average (2015).43


Technical Note: *A beach action can include beach-specific advisories or closings issued by the reporting state or local governments. A beach action is recorded for a beach even if only a portion of the beach is affected. During a beach closure, water conditions are deemed unsafe for swimmers and other users. “Preemptory actions” (advisory/closure) that some jurisdictions issue to inform the public of possible fecal contamination, issued based on past experience, prior to receiving from the laboratory a confirming water quality.


42 EPA, Beach Advisory and Closing On-line Notification, accessed January 30, 2024; watersgeo.epa.gov/beacon2/reports.html.

43 Long Island Sound Study Comprehensive Conservation and Management Plan, 2015; longislandsoundstudy.net/our-vision-and-plan/.