As you hit the sand this summer, consider this: You may be swimming in a giant cesspool of bacteria. Yeah, talk about that Dirty Water.

A new report from local non-profit Save the Harbor/Save the Bay has ranked 18 beaches in the greater Boston area according to their cleanliness. Using data from the Massachusetts Water Resources Authority, Department of Conservation and Recreation, U.S. Environment Protection Agency, the rankings were determined based on the percentage of time it was safe to swim at that given location, as well as the accuracy of the system that decides if the water is clean enough for to swim in, according to the Associated Press.

Nantasket Beach in Hull ranks at the top of the report for cleanest beach in the area, followed by South Boston beaches like M street and City Point, which are clean 94 percent of the time. The Southie beaches were also found to have a 94 percent accuracy rate in determining swimming safety.

On the other end of the spectrum, King’s Beach in Lynn fell at the very bottom of the list, with a cleanliness rate of 73 percent. Tenean Beach in Dorchester comes in next at 79.5 percent, followed  by Short Beach in Revere at about 83 percent and Winthrop Beach at about 85 percent.

Bruce Berman, director of communications strategy and programs for Save the Harbor/Save the Bay, tells the AP:

“I think King’s beach is a place where if we don’t address the problem, then I could imagine a time in the future when people are going to say we shouldn’t have people swimming here and that would be a shame.”

That would be more than a shame, sir. Just thinking about the bacteria I’ve possibly shared a Saturday afternoon swimming session with makes my skin crawl. Talk about a way to ruin summer. Clean it up, Bay State!

The remainder of the list will be presented at a meeting tonight in Boston with scientists, agency and government officials. Hopefully, the list will be a motivating factor to make our beaches the safest they can be for public swimming.