Rock Co. public health officials warn of blue-green algae blooms in Rock River, Lake Koshkonong

Blue-green algae in the Rock River
Courtesy of the Rock County Public Health Department

JANESVILLE, Wis. — Rock County public health officials are asking the public to avoid some local waterways due to the presence of blue-green algae.

Cyanobacteria, also known as blue-green algae, has recently been spotted in the Rock River and on Lake Koshkonong. The algae blooms are typically characterized by a blue-green or white color that can also have a foul odor.

When ingested, the algae can cause vomiting, diarrhea, nausea and other similar symptoms. Coming in contact with it can also cause skin or eye irritation.

Health officials said it’s especially important for small children and pets to avoid the algae because it’s difficult to determine toxin concentrations.

Rock County health experts said people should avoid swimming in areas with a high algae concentration. Folks should also avoid ingesting effected water.

If you think you’ve gotten ill from exposure to the algae, experts said you should contact your health care provider immediately.