ITHACA, N.Y.—The Tompkins County Health Department stated Tuesday that harmful algal blooms (HABs) have potentially returned to Cayuga Lake, as reports of “multiple suspicious blue-green algae blooms” have been submitted over the last two weeks.

Monitoring of the blooms is ongoing. There does not appear to be closures in relation to the blooms currently, but the health department is encouraging people to stay away from them where they are visible.

“These blooms may be small in size and confined to specific areas of the shoreline and bays,” according to the health department. “Areas where blooms are not observed can continue to be used for recreational use.”

The blooms can be toxic, producing substances that are harmful to people and animals, and the water should be avoided if it “appears discolored or has an unpleasant odor.”

From the TC health department:

If contact occurs with suspicious blue-green algae,

  • Rinse thoroughly with clean water to remove algae. Rinse dogs that may have gone in the water so they do not lick their coats.
  • Stop using water and seek medical attention immediately if symptoms such as vomiting, nausea, diarrhea, skin, eye or throat irritation, allergic reactions or breathing difficulties occur after drinking or having contact with blooms or untreated surface water.

The Cayuga Lake Watershed Network, Discover Cayuga Lake, and the Community Science Institute (CSI) have a volunteer program to conduct HAB monitoring of Cayuga Lake. The information is updated weekly and results are available on the CSI website:

Matt Butler is the Editor in Chief of The Ithaca Voice. He can be reached by email at