Observations: We checked on Honeoye Lake yesterday and today (8/13 & 8/14). We found a significant increase in Gloeotrichia in the water column. Also, a couple of isolated near shore Gloeotrichia blooms like this one:
We collected an open water and near shore algae sample yesterday. We then examined these samples with a microscope. We only saw Gloeotrichia in our algae samples. However, we have reached the time of the year when we usually have Anabaena and Microycstis blooms. Anabaena looks like pea-soup and Microcystis looks like green paint on the lake's surface. Be extra watchful for new blue-green algae bloom for the rest of the summer. Please report any suspicious blooms to us at watershedtaskforce@gmail.com .
August 10, 2020 Honeoye Lake Update (Click Here)
Surface Water Temperature: 79.3 F
Water Clarity: 7.5 Feet
Lake Level: 803.2 Feet above sea level
Lake Level Relative to Weir: -0.3 Feet
Observations: Monday (8/10/20), lake is in excellent condition for mid-August. There was light to medium Gloeotrichia (blue-green algae) visible in the water column. We did not see any surface algae scum in near shore areas.
Gloeotrichia is a species of blue-green algae that gets its nutrients directly from the bottom sediments. https://www.honeoyelakewatershed.org/habs
Water clarity has decreased by 0.7 feet to 7.5 feet since last week due to an increase in algae in the water column. This is very normal water clarity for mid-August (Water Clarity Ave. ~8 Feet). Surface water temperature declined slightly to 79.3 F.
The lake is now very “weakly” stratified and the water near the bottom below the thermocline has very low dissolved oxygen (anoxic). This means that the phosphorous/iron bond in the bottom sediments will weaken releasing phosphorus into the water near the bottom. The next time we get a North or South wind of 15-20 MPH we may have a lake mixing event that will mix this phosphorus into the whole water column top to bottom providing fuel for a blue-green algae bloom.
Our lake Temperature and Dissolved Oxygen graphs on the left show how the lake has gone from being strongly startified to weakly stratified over the last month.
On July 9th there was 7 degrees C difference between surface and bottom water temperature. On August 10th there was only 2.6 degrees C difference between surface and bottom temperature. The larger the temperature differential the higher the lake’s resistance to mixing.
1 meter (m) = 3.3 Feet and 1 Degree Centigrade ( C ) = 1.8 Fahrenheit (F)
Always use your own visual assessment before making contact with the lake water at this time of year as the blue-green algae situation can change daily if not hourly. Please regularly check the DEC HABs alert map for more detailed updates on Honeoye Lake HABs alerts: