A possible blue-green algae bloom in Hemlock Lake, the primary source of Rochester drinking water, was identified Thursday afternoon.
Blue-green algae can release toxins that are harmful to human and animal health, and discovery of a bloom in a drinking-water source is always a matter of some concern.
City spokesman Justin Roj said the possible bloom has had no effect on the drinking water supply and was already beginning to break up by Friday.
The bloom at Hemlock was found in the lake’s open water. No other information about the occurrence was available. The event was posted late Friday on New York state’s harmful algal bloom alert page.