WEST BLOOMFIELD (WWJ) – The Oakland County Health Division is continuing to test the waters at local beaches to make sure it’s safe to swim this summer.

As of Thursday afternoon, just one beach was closed — Scotch Lake Residence in West Bloomfield — after the water tested positive for high levels of E. Coli.

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What does that mean?

“It’s a naturally occurring bacteria in the guts of all warm-blooded animals; any mammal that likes to live and swim in the water,” explained OCHD spokesman Mark Hansell. “So, the results of these samples will come back to us from the laboratory and they’re measured against a state standard of E. Coli that could lead to a closure depending on the levels of the E. Coli.”

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Hansell said, ideally, they’d have no beach closures.

“But I think, due to the persistent rain events that we’ve had this spring, (E. coli) had shown up in our sample results a little bit, and we are doing what we can to continue to sample this one beach that, anyway, has had to remain closed,” Hansell said.

Hansell said when a beach is closed, they test the waters daily until its safe to reopen. The county tests the water at 100 public and semi-public beaches on 61 different lakes in the county on a weekly basis, mid-May through early September.

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Meantime, in neighboring Macomb County, St. Clair Shores Memorial Park Beach has been closed since July 9 due to E. Coli.