Water quality grades are in for urban beaches in Greater Boston and, for the most part, the ocean is clear.
More than half of the 15 beaches where the nonprofit group Save the Harbor/Save the Bay conducted testing last year posted perfect water quality scores, meaning all samples examined for bacteria were deemed safe for swimming under state public health standards.
At the bottom of the rankings were King’s Beach on the Lynn-Swampscott line and Tenean Beach in Dorchester, where bacteria levels were considered unsafe during about a quarter of last year’s swimming season.
Bruce Berman, the group’s director of strategy and communications, said the high marks for many beaches are significant given the record 61 inches of rain that fell in Massachusetts last year. Without the proper infrastructure, stormwater unleashed during storms can pollute beach water, he said.
