'Swimming may cause illness.' Popular Cape Cod beach closed to swimming. What we know.

One of Cape Cod's signature beaches is temporarily closed to swimming.

According to a Tuesday evening Facebook post from the Cape Cod National Seashore, Marconi Beach in Wellfleet is temporarily closed to swimming due to bacteria levels that exceed standards. An alert is also posted on the Seashore's website.

A sign at the beach on Wednesday morning warned visitors that "Swimming may cause illness."

According to the Facebook post, samples collected by Seashore staff prompted the closing. Updates will be provided as more samples are collected, according to the Seashore.

Marconi Beach is on the Atlantic Ocean. It features a spectacular natural setting with miles of open beach stretching north and south from the parking area. The large parking lot has 530 spaces and rarely fills up, even on the busiest summer day.

Are entrance fees being collected at Marconi Beach?

A Cape Cod Times photographer on the scene Wednesday morning reported entrance fees were still being collected at Marconi Beach and lifeguards were present. The parking lot was nearly empty.

Have Cape Cod National Seashore beaches closed for bacteria before?

Beach closings for high levels of bacteria are not unprecedented at Seashore beaches. According to a Cape Cod Times story, in 2012, Race Point Beach in Provincetown was closed to swimming from July 17 through part of July 19. Marconi Beach in Wellfleet and Nauset Light Beach in Eastham were closed from July 31 until Aug. 3. Head of the Meadow Beach in Truro and Nauset Light Beach were closed Aug. 21 and reopened Aug. 23.

Folks can also keep track of beach closings across Massachusetts at the state Department of Public Health's Interactive Beach Water Quality Dashboard website.

Eric Williams, when not solving Curious Cape Cod mysteries, writes about a variety of ways to enjoy the Cape, the weather, wildlife and other subjects. Contact him at ewilliams@capecodonline.com. Follow him on X: @capecast.

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