Over 200 Massachusetts beaches were deemed to be potentially unsafe due to fecal bacteria at some point last year, a new report revealed Tuesday.
Of the 583 beaches tested, 223 were deemed potentially unsafe on at least one day in 2018, according to the report by Environment Massachusetts.
A beach was considered unsafe if the amount of fecal bacteria in the water surpassed the threshold set by the U.S. Environmental Protection Agency. Fecal bacteria comes from sewage and can cause a variety of illnesses.
Three sections of Nahant Beach in Lynn were among the five spots where potentially unsafe conditions were most frequently found.
The section of Nahant Beach near Eastern Avenue had potentially unsafe conditions 42% of sampling days, the report said. At Pierce Road and Kimball Road, the beach was found to be potentially unsafe on 25% and 23% of sampling days, respectively.
Tenean Beach in Boston's Dorchester neighborhood had unsafe levels on 28% of sampling days; while the Quincy Shore at Channing Street had unsafe levels on 19% of sampling days, according to the report.
The Massachusetts Department of Health, meanwhile, found fewer cases of beaches being unsafe. Of the 583 locations where samples were collected in 2018, 157 had "at least one exceedance of a water quality standard," Ann Scales, the director of media relations, told NBC10 Boston.
In-depth news coverage of the Greater Boston Area.
The report listed several possible reasons for fecal contamination in oceans and lakes, including urban runoff, sewage overflows, failing septic systems and areas with concentrated livestock manure. Additionally, the flooding that comes with extreme weather events can spread fecal pollution, the report said.
Environment Massachusetts said government officials should undertake efforts to prevent runoff pollution. It recommended that urban green spaces, rooftop gardens and permeable pavement be created to prevent sewage overflows.
The group supports a bill making its way through the Massachusetts legislature requiring sewage operators to announce all sewage discharges.
The report was first released on July 23, but was revised at the beginning of August to correct methodological errors. The mistakes led to the report falsely saying certain beaches were unsafe, according to USA Today.
Environment Massachusetts used data from the National Water Quality Monitoring Council to compile the report.