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More confirmed algae blooms on Canandaigua, Seneca lakes

  • / Updated:
  • Staff Report 

Two major lakes in the region saw confirmed harmful algal blooms by local watch groups. The reports come as highs push into the mid- and upper-80s in the first week of October.


Canandaigua Lake’s outbreak was significant

Canandaigua Lake experienced a widespread outbreak of cyanobacterial harmful algal blooms (cyanoHABs) on October 2 and 3, affecting numerous shoreline areas.

Following a water quality alert on Monday, trained volunteers and local authorities provided 51 reports, with 74% confirming the presence of HABs.

Out of 19 samples collected, all but one exceeded the DEC’s 25 ug/L threshold for cyanoChlorophyll levels, marking significant bloom activity. Public access areas where blooms were detected were swiftly cordoned off by municipal partners to prevent exposure to residents and pets.

The Canandaigua Lake Watershed Council has been actively researching the movement of the cyanoHABs throughout the water column.

Lake conditions can shift rapidly due to various factors like wind patterns, water temperature, and nutrient inputs, making it challenging to predict the emergence and location of these blooms. Authorities have advised residents to be vigilant and avoid water with visible discoloration or surface streaking. On Wednesday, fewer reports were received, suggesting a potential decline in the bloom activity.

CyanoHABs, commonly referred to as blue-green algae, play a vital role in consuming atmospheric carbon dioxide and releasing oxygen. However, when they occur in high concentrations, they can produce toxic compounds harmful to humans and animals. Residents and visitors are urged to stay informed and exercise caution when encountering suspicious-looking water.

Seneca Lake sees surge of HABs amid warm weather

Between September 25 and October 1, eight confirmed harmful algal blooms (HABs) were reported on Seneca Lake, all of which appeared on October 1 in the lake’s Northwest portion.

In the following two days, another 12 blooms were verified. Weather conditions forecasted for the week could further promote bloom formation, prompting a warning to residents and visitors.

Anyone suspecting a bloom can report to the Seneca Lake Pure Waters Association by sending photos and location details to [email protected].

During the recent period, volunteers carried out 53 shoreline surveys.

While HABs have been a cause for concern, the association highlighted that Cladophora, a common green algae, is frequently misidentified as a HAB.

Unlike blue-green algae, Cladophora, which grows on submerged surfaces and is prevalent in Seneca Lake, does not produce toxins. It can detach and surface due to wind and wave actions. In contrast, genuine HABs are easily dispersed by these same factors.