E. coli or enterococci, which indicate fecal matter contaminating water, were detected at swim spots in New York state, Massachusetts, Michigan and elsewhere, authorities said.

A seaside escape is always a popular summer activity, particularly for Fourth of July festivities, but with potentially harmful bacteria in various bodies of water, some beaches could be closed this holiday.

Over 20 beaches in Massachusetts are closed on July 4 across the state, according to the Massachusetts Department of Public Health’s Interactive Beach Water Quality Dashboard. A total of 22 beaches are closed in towns such as Ashby, Beverly, Dartmouth and Salem.