New bacteria test results show it is safe to swim at 11 of the 33 beaches closed yesterday, according to the Department of Public Health.
Beaches in Beverly, Hingham, Marshfield, Duxbury, and New Bedford have reopened.
But three state beaches in or near Boston remain closed to swimming today: Carson Beach in South Boston, Tenean Beach in Dorchester, and Wollaston Beach in Quincy, according to the Department of Conservation and Recreation.
More test results are expected later today, which could reopen more beaches, including nine Quincy beaches that were closed to swimming yesterday.
Officials have warned against swimming at the beaches because of high levels of enterococcus, which can cause skin irritation, vomiting, or diarrhea.
The beaches that reopened today:
Beaches in Salem, Nahant, Wareham, Chatham, Somerset, Swansea, and Martha’s Vineyard remain closed pending new test results, according to the Department of Public Health website. Peggotty Beach in Scituate will remain closed through the weekend until a new test can be taken on Monday, according to the town website.
Officials said high counts of enteroccus can wash away quickly with tidal changes.
In an apparent example of Mother Nature’s cleansing power, bacteria at Kimball Beach in Hingham dropped drastically in two days. A Tuesday test showed 6,020 colony-forming units (CFU) of bacteria in 100 millileters. (Beaches are closed at 104 CFUs per 100 ml.) A test taken Thursday showed less than 10 CFUs in 100 milliliters.
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