Through some of the hottest weeks of the year, dozens of Massachusetts beaches have been closed over high levels of bacteria. This week, the state public health department received a new grant to support testing the commonwealth’s waters and getting the word out about where it’s safe — or unsafe — to swim.

A $275,000 grant from the U.S. Environmental Protection Agency will help the Massachusetts Department of Public Health with its water quality monitoring and public notification programs, part of nearly $11 million that’s being distributed to coastal and Great Lakes communities.

"What we really are worried about at the Department of Public Health are those that are most vulnerable," Dr. Robbie Goldstein, the commissioner of Massachusetts’ Department of Public Health, said at a press conference Friday. "Children who oftentimes are swimming in these waters, the elderly and certainly those who are immunocompromised ... may be exposed to these types of bacteria and end up with very significant illness."

Fifty-five beaches are currently closed, which Goldstein attributed — in part — to heavy rain and sewage overflows.

Susan Hamilton, acting deputy commissioner of operations at the state’s Department of Conservation and Recreation, said the hotter, wetter summers can overwhelm that state's storm and sewer systems. This summer has been much wetter than last summer.

Hamilton said more signage would be posted to alert beach visitors of high bacteria levels in the water. She also urged locals to clean up after their dogs, ensure young children wear swim diapers and not feed the geese to keep water clean.

Beaches’ water quality are currently tested once a week. Those that fail their tests — or have a poor record — get more frequent testing.

While the state’s beaches are much cleaner than they were 50 years ago, U.S. EPA Regional Administrator David Cash said that more has to be done.

“We particularly have to do better in communities who are disadvantaged, Black and brown communities, where we do find a disproportionate number of these kinds of assets not available,” Cash said.

The Department of Public Health keeps a list of beach closures online at its Beach Water Quality Dashboard, updated twice a day with the latest information.