Over the last two weeks we have seen a gradual diminishing of blooms around the lake. However, we did have three reports of potential blooms yesterday with the 87 degree weather. We also went out on Sunday September 22nd after the bloom conditions of the previous two days and sampled for toxins and blue green algae concentrations in several different locations and depths to better understand the ambient (general levels) of both BGA and the associated toxin. The good news is that the toxin levels at each of the locations were below the 4 ug/L level that would cause the DOH to close a public swimming beach. The other good news was that the BGA levels were low: 1-2 ug/L. However, the concerning part was that we had detectable levels of toxin in the water even though the BGA levels were low. There were dots in the water in each location that we sampled. We are seeing a little more algae diversity in the water with harmless green algae and diatoms starting to show quantifiable levels.
Based on this information - please continue to use your visual indicators before entering the water. Please do the same for your pets. We are finally starting to see some of the results from the DEC sponsored toxin testing that occurred earlier this season and it is confirming that when we have bloom level concentrations we are seeing high toxin levels in those samples.
Our public water supplies continue to show nondetectable levels of the toxin in the finished water indicating that they are adequately treating the water for human consumption. Users of private water systems (those not on municipal water, who are using their own surface water intake or nearshore well) need to continue to use caution and make sure their treatment system can adequately treat for the toxin. If you are seeing blooms in the water, it is recommended that you do not use your private water system. We did sample for toxins at an approximate 12 ft water depth because private water supplies intake lines are typically at that depth. Each sample came back showing toxin levels in the 1-3 ug/L range. Work with your private water treatment system provider to make sure the system is functioning adequately.
Questions? Send to HABS@canandaigualakeassoc.org.
Kevin Olvany Lindsay McMillan
Watershed Program Manager Association Director
Canandaigua Lake Watershed Council Canandaigua Lake Watershed Council