Harmful algal bloom activity increased significantly on Seneca Lake this week, with 13 blooms confirmed since September 11, according to Seneca Lake Pure Waters Association.
Eleven of those 13 confirmed blooms were reported Thursday, when calmer conditions followed several windy days that may have helped suppress bloom activity earlier in the week. Most of the reports came from the northern end of the lake, though Pure Waters cautioned that the concentration could partly reflect where more volunteers and residents were actively watching for blooms.
The increase comes as water temperatures remain relatively warm heading into the second half of September. Surface water measured 69.6 degrees Friday morning at a depth of 3.3 feet, according to data included in Pure Waters’ weekly water quality update.
Dissolved oxygen was measured at 105% in the upper 33 feet of the lake Thursday evening.
Pure Waters said conditions can change quickly and urged people using the lake to watch for discolored water, surface streaks, scum and other signs of a possible harmful algal bloom.
HABs can resemble pea soup or spilled paint and may appear as bright green or blue-green water, green streaks or swirling mats. Blooms can also accumulate along shorelines and in protected coves.
People and pets should stay out of water where a suspected bloom is present. Pure Waters recommends photographing suspected blooms, noting their location and reporting them to the state Department of Environmental Conservation.
Meanwhile, recent rainfall has helped stabilize Seneca Lake’s water level after a steady decline through much of the summer. The lake stood at 445.12 feet BCD Friday morning, slightly above its level at the same point last year, according to Pure Waters.
The association’s weekly update draws on data from the Finger Lakes Institute’s real-time monitoring buoy, Pure Waters volunteers and NOAA.
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