Putnam, Fla. – The Florida Department of Health in Putnam County (DOH-Putnam) is cautioning the public of the presence of blue-green algae in Crescent Lake on July 10th, 2024. Water sample testing is underway. Blue-green algae have the potential to produce toxins. Since environmental conditions can change at any time, it is important to exercise caution, even if presence of toxins has not yet been confirmed.