Health officials warn of harmful algal blooms on Canandaigua and Finger Lakes

August 8, 2026 - 14:08

Local health departments are urging residents and visitors to exercise caution as harmful algal blooms, or HABs, have been detected in Canandaigua Lake and other parts of the Finger Lakes region. The blooms, which appear as green, blue-green, or even reddish scum on the water's surface, can produce toxins that are dangerous to both people and pets.

Officials say the blooms are most likely to form in warm, calm, and sunny conditions, which have been common in recent weeks. While not every bloom is toxic, testing has confirmed the presence of cyanobacteria in several samples. Exposure can cause skin irritation, stomach cramps, vomiting, and flu-like symptoms. In severe cases, ingesting the water can lead to liver or nervous system damage. Dogs are especially at risk because they may drink the water or lick their fur after swimming.

The advisory specifically covers areas near the shoreline where blooms tend to accumulate. Health officials recommend avoiding any water that looks discolored or has a floating scum layer. They also advise against fishing, swimming, or boating in affected zones. If you do come into contact with the water, rinse off with clean, fresh water as soon as possible.

Local authorities are monitoring the situation closely and will update the public if conditions change. For now, the safest approach is to stay out of any water that shows visible signs of a bloom. Farmers and residents who draw drinking water from the lake should also check for any unusual taste or odor and consider using an alternative source until the bloom clears.