The Boston-area beaches with the best (and worst) water quality, according to a new report

Local News

Two South Boston beaches were deemed the safest, while historic rainfall negatively impacted other swimming spots last year.

Where are the safest beaches in the Boston area? A new report has the answers.�

Local nonprofit Save the Harbor / Save the Bay released its annual “Beach Season Water Quality Report Card” Monday, which assigns various beaches water quality safety ratings between zero and 100% based on data from the previous year. The scores are based on data from the Department of Conservation and Recreation.

Pleasure Bay and City Point beaches, both located in South Boston, continued to receive the highest marks. The nonprofit called South Boston’s beaches the “cleanest urban beaches in the country.” Both Pleasure Bay and City Point received scores of 100% for the 2023 season, continuing a trend of perfect ratings that stretches back five years.�

At the other end of the spectrum is King’s Beach in Lynn, which garnered a rating of 55% for the 2023 season. It is the lowest score that any of the 15 beaches included in the report received.�

“King’s Beach is an outlier in the Boston area,” Save the Harbor Executive Director Chris Mancini said in a statement. “It’s a difficult and complex infrastructure challenge that has required dozens of meetings between stakeholders at every level of community and government. We’re very lucky to have such a committed, collaborative group from Lynn, Swampscott, the state and the federal government focused on trying to turn this beach around.”�

Tenean Beach in Dorchester received the second-lowest score, 73%. The largest decreases in beach safety between 2022 and 2023 occurred at King’s Beach and Dorchester’s Malibu Beach. Both scores fell by 19%.�

Officials cited last summer’s record rainfall as a major factor in the 2023 scores. Lots of rain can lead to sewer overflows and runoff from streets entering the water at beaches. This causes an increase in bacteria levels, making beaches unsafe. Harmful algae blooms also force a number of beaches to close throughout the summer.�

State officials regularly test water quality at beaches around Massachusetts, temporarily closing the ones that pose an outsize risk to residents. Ten beaches were closed across the state as of Tuesday morning. The Department of Public Health maintains an interactive dashboard of all beach closures that is updated twice a day.�

Officials delineate water samples between those collected at freshwater beaches and those collected at marine beaches. About 8% and 5.6% of samples collected from marine and freshwater beaches, respectively, exceeded bacterial water quality standards in 2023, according to a MDPH report.�

“While exceedances were above average in 2023, the overall low historical exceedance rates indicate that Massachusetts beaches generally have high water quality,” the authors of that report wrote.�

Still, 2023 was the rainiest summer in the Boston area since 1955, according to the Save the Harbor report. This resulted in an overall water quality safety rating of 85% for Boston Harbor area beaches in 2023, down from the previous 93% score.�