Blue Green Algae Update
We conducted visual surveys of the shoreline today. The wind was a gentle breeze out of the northwest so we visited multiple sites along the east side of the lake. The water was clear and showed no signs of blooms or surface streaking. Some dots of Blue Green Algae could be seen in the water column in one area but not at significant concentrations. Overall conditions looked very good in the areas that we have been seen isolated concentrations of Blue Green Algae. There seemed to be enough wind to break up any concentrations on the east side. If anyone is seeing anything different please let us know.
Yesterday, Dr. Bruce Gilman and Watershed Technician Kim McGarry were on the lake for 3+ hours and completed field analysis and visual assessments in open water and shoreline areas. Some areas of the lake had a small amount of surface streaking and dots of algae were visible in the water column. However, we did not observe any dense concentrations like the samples taken on Monday. Our secchi disk reading in the open water was 7.4 meters (a 1.4 meter increase from Friday) which indicates that the overall water clarity is very good for this time of year and we do not have a significant density of Blue Green Algae throughout the water column. Dr. Gilman collected 2 shoreline and 2 mid-lake samples to get a sense of the overall levels of algae in the lake. Each of the samples had very low total chlorophyll-a. The range was 0.9 to 5.18ug/L. We could also easily see the bottom in the shoreline areas.
We have also received the results from the 3 samples collected on Monday. These samples were collected along the shoreline where the BGA was accumulating in isolated locations and are representative of the very worst case scenario areas that had the densest blue green algae. The blue green algae chlorophyll a in these areas ranged from 129.5 ug/L to 701.3 ug/L. These samples were well above the DEC threshold of 25ug/L for a bloom. We do not have any results from the toxin testing yet, but will provide them as they become available. However, it is important to note that the vast majority of the lake was not experiencing these types of conditions Instead, these types of blooms were isolated and were located along small sections of shoreline where the wind caused the algae to concentrate. We have not observed any concentrations to this level on Tuesday or Wednesday. If residents are seeing concentrations please email us pictures at Kevin.Olvany@canandaiguanewyork.gov or Kmcgarry@canandaiguanewyork.gov.
This warm, sunny and calm weather continues to provide potential excellent growing conditions for algae. Conditions can change quickly on the lake, so we cannot say where blue green algae will be present and whether it will reach bloom conditions. Before going into the water, look for signs of blue green algae. If you see anything suspicious, avoid it!
Clear waters observed today.
Some light surface streaking on the lake was observed in a few locations on the lake on Tuesday, but was not observed lake-wide.
Photo of Monday’s highest concentration sample.