The Tompkins County Health Department says harmful blue-green algae has been found in Cayuga Lake. In a press release, the Department says the Harmful Algal Blooms (HABs) have been “visually identified” on each side of the Southern end of the lake, and that the New York State Department of Environmental Conservation has confirmed the HABs.

Ingesting water infected by blue-green algae can make humans and pets ill. The Department is urging residents to look out for strongly colored water, a paint-like surface and floating mats or scum. You can see sample images here of both HABs and non-toxic green algal blooms.



Boiling, chlorinating, or otherwise treating your water will not make it safe to use during a bloom. The Department has this instruction: “During a bloom, do not drink, prepare food, cook, or make ice with water from the lake or from beach wells.”



Pets should also be kept from drinking untreated surface water. People in contact with blue-green algae should rinse thoroughly afterward. The state Health Department has more instructions here.



Residents are still encouraged to use the lake for summer recreation, but to take extra precautions. Tompkins County Health Department is updating this page with more information.