The first week of fall is upon us. We are starting to see docks coming out for the season, boats getting winterized, and a renewed focus on yard chores.
Here at CLWA, we are still going strong with a dedicated group of volunteers continuing to submit their weekly secchi disk reports and send in shoreline HABs surveys. We thank them for their ongoing efforts to provide us with lake condition reports. Last week (week ending 9/20), 9 volunteers submitted clarity readings with a weekly average of 5.47 meters, which was an increase in water clarity from the previous week’s average of 5 meters (week ending 9/13). Remember that clarity is a measure of algal abundance and suspended sediments in the water column. Volunteers also reported a drop in the average surface water temperature this past week. Clarity is increasing, and surface water temperatures are starting to decrease, which should result in fewer HAB reports as we move through October.
We have, however, had several blooms reported so far this week, including three bloom reports coming in just this afternoon. Today's calm winds and sunny weather are the perfect conditions for HABs. Therefore, it is still wise to scan the shoreline before entering the water or letting pets swim.
Volunteers collected 4 samples earlier this week from very obvious bloom areas and results from the Finger Lakes Institute indicate elevated levels of CyanoChlorophyll (blue green algae). This week we had our highest blue-green cyano level of the 2020 season, from a sample taken just north of Vine Valley (see photo). Below are the results from samples collected this week.
How to interpret these results:
The values in this table are reported in ug/L, which is micrograms per liter.
DEC threshold for a bloom is 25 ug/L of CyanoChlorophyll (blue green algae).
These results are telling us that these isolated blooms must be avoided. These particular blooms were not tested for toxins; however, based on previous data collected we know that Canandaigua Lake blooms with high levels of blue green algae may also have high levels of the microcystin toxin. Exposure to blooms and toxins can cause symptoms such as diarrhea, nausea or vomiting; skin, eye or throat irritation and allergic reactions or breathing difficulties.
The six Canandaigua Lake water purveyors (the City of Canandaigua, the Village of Newark, the Village of Palmyra, the Village of Rushville, the Town of Gorham, and Bristol Harbour) continue with their routine testing of the public drinking water for the presence of toxins associated with harmful algal blooms. So far there have been no detectable levels of toxin in the finished drinking water. Results from routine sampling can be viewed here: https://www.canandaigualakeassoc.org/drinking-water-test-results/.
We thank you all for your continued support and ongoing efforts to help us monitor and protect the lake. We hope you will check out the tips below for ways you can help keep nutrients out of the lake when doing that fall cleanup around your property in the coming weeks. Remember, excess nutrients may fuel algae blooms and aquatic plant growth! Homeowners are all stakeholders in our watershed health, so let’s do our part to reduce our collective impact. Our watershed will thank us.
Thanks,
CLWA & CLWC
Cooler daily temps and chilly nights certainly have us feeling like the end of summer is near! The cooler temps have also resulted in fewer reported blooms. However, we know they can still pop up when the conditions are just right. In fact, this week volunteers reported 3 potential blooms out of the 27 shoreline surveys that were performed.
On Thursday, we received results from the microcystin toxin analysis that was performed on samples collected from both intense bloom areas and open water non-bloom areas the day after Labor Day (Tuesday, September 8th). While these results are 10 days old and not indicative of current lake conditions, they are of interest because 9/8/2020 was our most significant day of blooms this summer, with many areas of the lake experiencing streaking and/or green colored water. It further confirms that blooms need to be taken seriously.
How to interpret these results:
The values in this table are reported in ug/L, which is micrograms per liter.
DEC threshold for a bloom is 25 ug/L of CyanoChlorophyll (blue green algae).
Microcystin is the toxin that may be produced during a bloom. Microcystin advisory thresholds for shoreline and open water can be found in the graphic below.
Microcystin results came from a NY State certified lab.
When reviewing these results, you will note that the four samples from open water areas (samples collected from a boat) were all well under the DEC threshold for a bloom. Shoreline areas on the other hand, all had extremely high CyanoChlorophyll levels, well over bloom threshold.
The story is the same for toxin results. Open water samples had less than 1 ug/L of microcystin. All the shoreline samples that were sent on for toxin analysis came back well above the 20 ug/L NYS threshold for a “High Toxin” bloom.
These results are showing us that shoreline – as well as open water areas – in active bloom situations must be avoided, as they have potential to have extremely high toxins that can be harmful to humans and pets. The shoreline areas with shallower, warmer waters have the highest likelihood of a potentially harmful bloom, and it is often where water recreation occurs.
Conditions have changed greatly since the day these samples were collected, and remarkably, the day after these samples were collected the water appeared very clear in many areas.
As summer draws to a close next week, we hope to still get in a few more nice lake days! Please remain aware that conditions can change quickly and to keep an eye out for signs of a bloom before you or your pets enter the water - look for surface streaking, pea-soup like conditions, and green cloudy water. These areas should be avoided.
In coming weeks, we hope to share more info on projects and programs in action that are aimed at protecting Canandaigua Lake water quality. We know that a healthy, protected watershed is one of the keys to clean water. Please considering tuning into a webinar next Wednesday, September 23rd at 10:00 on the gypsy moth, which has been devastating out watershed forests this year. The program is hosted by Finger Lakes ReLeaf, and registration is required. We hope you’ll tune in to learn more!
Thanks,
CLWA & CLWC
This has been an interesting week for water quality. As we reported earlier this week, on Tuesday, September 8th (the Day after Labor Day) the lake was experiencing a significant bloom event along much of the 36 miles of shoreline. Conditions ranged from areas with light streaking and heavy suspended algae, to full on pea-soup conditions. 22 bloom reports were filed by volunteers on 9/8 (see a sampling of photos below). By Wednesday - also a calm, sunny day- many shoreline areas were clear, though we did receive a few reports of mid-lake streaking. 3 bloom reports were filed on Wednesday the 9th. Many additional shoreline and mid-lake surveys were performed by the Watershed Manager as well.
The cooler temps and slight north wind on Thursday and today seem to have kept blooms at bay. We are seeing some foam accumulation today.
Historically, September has been the month where we experience our most intense blooms in terms of CyanoChlorophyll values (blue green algae) and microcystin values (the toxin associated with blooms). In September 2018, several CyanoChlorophyll values skyrocketed into the 1,000s (ug/L), when the DEC threshold for a bloom is 25 ug/L. Many of these blooms also had high toxin values. In 2019, our highest values were also in the month of September. While we have not yet surpassed previous year’s levels, this is a good reminder that when blooms pop up, they need to be avoided because they have the ability to be potentially harmful to your health or the health of our pets.
Here is a table of the samples collected this week. Values are reported in ug/L, which is micrograms per liter. DEC threshold for a bloom is 25 ug/L.
.As you can see, many of the Blue Green Algae levels were very high along the shoreline areas. The four open water samples were well below bloom threshold and were collected to get a sense of levels away from the shoreline. We did have a few reports of blooms in the open water which is why we tell people to use their visual indicators before recreating in the lake. In fact, on Wednesday we had the reverse happen where the Yacht Club shoreline was clear of any visible algae and there were documented blooms of algae out in the mid-lake area.
Several other area lakes have also seen an uptick in blooms overs the last week, including Cayuga, Skaneateles, Owasco, Keuka and Hemlock.
Please remain aware that conditions can change quickly and to keep an eye out for signs of a bloom before you or your pets enter the water. Please continue to use your visual indicators to look for surface streaking, pea-soup like conditions, and green cloudy water. These areas should be avoided.
For more information throughout the week, you can check out the interactive Bloom Map from the volunteer efforts, which is updated in real-time on the CLWA website. Click on the dots to pull up more information on each bloom (date reported, images of blooms, description, etc).
Thanks,
CLWA & CLWC
Drinking Water
The six Canandaigua Lake water purveyors (the City of Canandaigua, the Village of Newark, the Village of Palmyra, the Village of Rushville, the Town of Gorham, and Bristol Harbour) are working alongside the Geneva District Office of the Health Department and the New York State Department of Health to monitor the public drinking water for the presence of toxins associated with harmful algae blooms. Samples of the public drinking water are routinely collected and sent to a State approved laboratory during the harmful algae bloom season to determine if toxins are present. Samples were collected the morning of September 8th and all treated finished water results were below the detection limit.
CLWA and the Watershed Council works with the water purveyors and the Geneva District Office of the Health Department to receive the results and make them available to the public. So far this year, all results from the finished drinking water have come back non detect. Results from routine sampling can be viewed here: https://www.canandaigualakeassoc.org/drinking-water-test-results/.
Private water system users that draw water from the lake (those who are using a home treatment system where water does not come from a public water treatment plant) may face challenges during active blooms due to the varying capabilities of household treatment units to remove cyanotoxins. We encourage those using a private system to use bottled water during active blooms and to work with a professional water service company to evaluate their treatment system.
