As summer unofficially begins, Boston-area beaches are getting good grades for water quality from a clean harbor advocacy group.
In its second-annual Beaches Report Card, Save the Harbor/Save the Bay said more than half the public beaches along Boston Harbor earned A or A plus scores in 2012, with many showing significant improvement over 2011.
Bruce Berman of Save the Harbor/Save the Bay said dry weather helped keep the beaches clean.
"Bacterial pollution is often caused by storm water discharges that accompany summer showers, squalls and storms, so less rain means cleaner water," Berman said in a statement about the report.
The grades were based on thousands of water samples collected last year by the state Department of Recreation and Conservation and the Massachusetts Water Resources Authority.
Revere Beach, Winthrop Beach, and Short Beach in Revere all received A plus grades.
Tenean Beach in Dorchester and King's Beach, on the South Shore, had the lowest scores, but both had better conditions than in 2011.
"Just 25 years ago, these beaches were awash with human waste," Berman told the Associated Press. "We should be proud of what we've done and be prepared to finish the job."
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