The Walden Pond oasis has been shut down to swimming because of elevated bacteria levels after the recent deluge of rain.

Walden Pond is the latest Massachusetts waterbody that has a “No Swimming” red flag warning as a result of all the torrential rain this summer.

“Due to elevated bacterial levels in recent sample, a No Swimming warning has been issued at Walden Pond Main Beach,” Walden Pond State Reservation tweeted on Thursday.

“The warning will remain in effect until subsequent sample results return to safe recreational water standards,” the state Department of Conservation and Recreation park tweeted.

This “No Swimming” warning at Walden comes after several inches of rain fell on Tuesday across the region.

With all the rainfall this summer, many DCR swimming areas have been testing positive for elevated bacterial levels. DCR posts a red flag at the beach if the water is unsafe for swimming.

“Rainfall washes everything that’s on the land into bodies of water, including bacteria from many different sources,” said Vanessa Curran, of the DCR Office of Water Resources.

DCR conducts weekly water quality testing, required by the state Department of Public Health, at all agency-managed waterfronts starting the week before Memorial Day through Labor Day.

When bacterial levels are high, “No Swimming” warnings are posted at the site immediately after receiving the test results. A follow-up test is typically conducted within the next 24 to 48 hours. If results show a reduction in bacteria to acceptable levels, warnings are removed from the waterfront.

Swimming in unsafe waters may lead to: gastrointestinal symptoms; respiratory symptoms; skin rash and itching; eye and ear irritation; and flu-like symptoms.

Other than Walden Pond, here are the bodies of water in Massachusetts that have “No Swimming” warnings as of Thursday: