Rock County Health Department officials in a release to the media on Tuesday note that conditions are right for cyanobacteria, also known as blue-green algae, to appear in local waters.

Within the their release, county health department officials say they have recently observed blue-green algae in the Rock River and Lake Koshkonong.

“Because it is hard to determine exact levels of blue-green algae toxin concentrations, anyone considering recreation on or in the water should use caution and common sense,” the release stated.

Additionally, the department encourages resident to take the following precautions:

• Avoid swimming in areas of high algae concentration. Stay away from water with a floating scum layer that looks like green, blue, or white paint or pea-soup.

• Do not swallow pond, lake, or river water. This is especially important for small children and pets.

• Rinse off after coming in contact with pond, lake, or river water. If you think you have become ill from exposure to blue-green algae, contact your healthcare provider immediately.

According to the release, blue-green algae are naturally present in Wisconsin ponds, rivers, and lakes. When conditions are favorable, the algae can grow rapidly and form blooms of bright green, blue-green, or white. They can form thick scum layers on the surface of the water and may look bubbly or frothy. The blooms may have a foul odor, particularly in warm summer months. Some of the algae can produce a toxin that may lead to harmful health effects if ingested.

Some symptoms of exposure include:

• Skin or eye irritation 

• Vomiting

• Diarrhea

• Cold or flu-like symptoms

Pets and children are particularly vulnerable to these conditions because of their size and because they don’t have a natural tendency to avoid these water conditions. Dogs also have an increased risk of illness from the toxins as they are likely to ingest the water, the release stated.

For more information about blue-green algae, county official suggest visiting the state’s website or the Rock County Public Health Department: 608-757-5440.