Toxic blue-green algae is spreading from Dunton Park to Holland State Park. Health officials said it's been known to develop before, but rarely to this extent.
Harriet Vanheest owns property near Lake Macatawa and said the water looks like pea soup.
"It would be nice to figure out what it is and how we can get rid of it," she said.
Health officials said because of the summer's heat, blue-green algae is lasting for months instead of days. They said it can develop in just 12 hours.
Many people along Lake Macatawa and Holland State Park were unaware of the warning on Tuesday. Several children were even playing in the water.
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