The sunny, hot weather that is forecasted for the next week or so could likely increase concentrations of harmful algae.

A blue-green algae bloom reported Friday on Canandaigua Lake has closed two swim beaches on the lake.

The New York State Department of Health closed Onanda Park Beach in Canandaigua for the entire weekend due to concerns relating to blue green algae. The park portion will remain open as normal; however, the beach portion will remain closed for the entire weekend, according to the announcement.

The swim beach at Deep Run on the lake’s east side in Gorham is also closed due to algae.

The beach at the town of Canandaigua's Butler Road School house remains open for swimmers. Kershaw Park in the city of Canandaigua also remains open.

Canandaigua Lake Watershed Association confirmed Friday afternoon certain shoreline areas of the lake show concentrations of algae containing the presence of cyanobacteria, the toxin of Harmful Algal Blooms.

“Overall, water clarity has been good in the lake,” stated Canandaigua Lake Watershed Manager Kevin Olvany. “However, we are starting to get some more reports today along the east side that they are seeing concentrations of algae. There is a gentle breeze that can skim and concentrate the algae on the windward side.”

“The sunny, hot weather that is forecasted for the next week or so could likely increase concentrations. Watershed staff and the growing volunteer network will be out looking at conditions and collecting samples where appropriate,” stated Olvany. “If the public sees concentrations of algae, streaks of algae or lots of dots in the water, we highly encourage people to avoid those areas.

Results from samples collected by trained volunteers on Canandaigua Lake confirmed the presence of cyanobacteria HABs in certain areas. The bloom status is compared to the DEC Confirmed Bloom threshold of 25 µg/L Bluegreen Chlorophyll. For more detailed information and a map of zone locations on Canandaigua Lake go to: http://www.canandaigualakeassoc.org/science-education/blue-green-algae-2/

Olvany urges people to email pictures and locations to: habs@canandaigualakeassoc.org.

Earlier this week, HABs was also reported on Seneca Lake. A water sample taken from the Perry Point area on the west side Seneca Lake showed toxic algae.

The Seneca Lake Pure Waters Association reported the bloom that is also being reported by the DEC.

Exposure to any cyanobacteria HABs can cause health effects in people and animals when water with blooms is touched, swallowed, or when airborne droplets are inhaled. This is true regardless of toxin levels; some blue-green algae produce toxins, while others do not. Exposure to blooms and toxins can cause symptoms such as diarrhea, nausea or vomiting; skin, eye or throat irritation and allergic reactions or breathing difficulties. People and pets should avoid contact with blooms, and should rinse off with clean water if contact occurs. For more information go to www.health.ny.gov/harmfulalgae