Beaches closed in Crystal Lake, Lake in the Hills, Wonder Lake on Friday due to high bacteria levels

Beaches in Crystal Lake and Lake in the Hills were closed Friday until further notice because of elevated levels of bacteria in the water.

In Crystal Lake, Three Oaks Recreation Area’s beach and Crystal Lake Main Beach were closed. West Beach remains open, according to the Crystal Lake Park District.

In Lake in the Hills, Butch Hagele and Indian Trail beaches also closed.

According to the Illinois Department of Public Health, Wonder Lake’s Deep Springs Wood 2, Wonder Woods 1 and Lookout Point beaches also closed because of bacteria levels.

The IDPH reported that Dorothy Court Beach in Island Lake also was closed. Island Lake is conducting treatment for algae and duckweed for five days, according to a Facebook post from the village Thursday.

The McHenry County Department of Health regularly tests for E. coli in the water of public beaches to indicate bacterial quality, as it is considered to be a “measure of fecal contamination,” according to the county health department website.

Beaches are closed when both shallow and deep lake water samples exceed the E. coli closing standard of 235 colony-forming units per 100 milliliters of water, according to the county health department.

Beaches will reopen once new samples confirm that E. coli readings drop to acceptable levels. Factors such as natural die-off, wind, waves and ultraviolet rays from the sun all help reduce the level of bacteria. But how long it takes for the levels to reduce varies, according to the McHenry County Department of Health.

There are a variety of reasons for elevated levels of bacteria in the water, including storm runoff from rainfall, agricultural runoff, wild and domestic animal waste, bather defecation and wastewater.

Swimmers exposed to such high bacteria could develop gastroenteritis-type illness, with symptoms such as diarrhea, nausea, vomiting, abdominal pain, headache, a low-grade fever, skin rashes and earaches. The McHenry County Department of Health advises anyone who experiences these symptoms after swimming at a public beach to contact a physician and the beach manager.

As for the prospect of beaches reopening Saturday, that appears in most cases to be a day-to-day decision. You can check the status at the Illinois Department of Public Health’s BeachGuard site here: idph.illinois.gov/envhealth/ilbeaches/public.