WATER QUALITY UPDATE For Friday, September 10, 2021
So far this week:
27 surveys performed
No Blooms Reported
Welcome to the 11th edition of your Friday Water Quality Update! These updates are drafted in partnership with CLWA and the Canandaigua Lake Watershed Council (intermunicipal watershed organization consisting of the fourteen watershed and water purveying municipalities). Current Lake Conditions We are happy to report that for the second week in a row, no blooms have been observed by volunteers or watershed staff. We did have two suspicious reports come in last weekend, but upon further investigation of the photos, it was determined that both reports were of watermeal / duckweed and were not harmful. Secchi disk volunteers are reporting water clarity readings in the 4.8 - 6.9 meter range so far this week, with an average of 5.86 meters of clarity. We have been holding in this 5-6 meter range for the last 2 weeks. Secchi disk readings are very important this time of year - if we begin to see a sharp drop in readings (down to the 3-4 meter range), that may indicate an increase in algal productivity and signify an upcoming bloom event. We thank the ongoing efforts of our secchi disk volunteers for providing these helpful reports! 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 their routine testing of both raw (untreated) and finished (treated) drinking water for microcystin (the toxin that may be produced by cyanobacteria / blue green algae). All results to date have come back as non detects. Results are uploaded weekly on the CLWA website. Overall, the water quality observations made this week are quite promising. However, it is important to remember that conditions can change quickly on the lake. Typically, we have seen our most significant bloom events in the early to mid-September timeframe. Please continue to use your visual indicators and look for signs of a HAB before swimming or letting pets into the lake. Blooms may appear as discolored water, surface streaking of blue green algae (cyanobacteria) or pea soup conditions. Volunteers and watershed staff will be continuing daily observations throughout September and we will communicate any significant changes in bloom activity through our weekly email updates, on our website, and on our facebook page. If you have a question on a suspected bloom, please feel free to send in a photograph to HABs@canandaigualakeassoc.org.
So far this week:
22 surveys performed
No Blooms reported
Welcome to your Friday Water Quality Update!
Current Lake Conditions
Through our monitoring network of Watershed Council and Association staff, Canandaigua Lake Watershed Association volunteers, and reports from the general public - we have had zero blue green algae (cyanobacteria) blooms this week. Overall, water clarity is holding in the 5.5- 6.0 meters as measured by a secchi disk, which is good for this time of year.
Since mid - August, we have also sampled open water levels of cyanobacteria ( blue green algae) on a weekly basis at nine locations in the northern third of the lake (historically the area with the highest open water concentrations). We have been trying to sample on days when we are getting reports of shoreline blooms and conditions are ripe for potential open water blooms. Results from our August 28th sampling showed blue green algae levels that ranged from 0.33-1.86 ug/L (micrograms per liter) with an average of 1.05 ug/L. The DEC threshold for a bloom is 25 ug/L. We also sampled at three of these locations for the microcystin toxin that can be produced by blue green algae. Two of the results were less than the 0.3 ug/L detection limit and one sample was 0.31 ug/L. The DOH threshold for re-opening a beach is less than 4.0 ug/L. We are very pleased with these results thus far. We will continue this sampling effort through early October.
Deep Run beach in the Town of Gorham, which is an Ontario County Park, was closed last weekend due to blue green algae. The NYS Department of Health tested the water quality of the beach on Monday, August 30th and the results indicated that the beach could be reopened. However, as with many of the other public beaches - lifeguard staffing issues may not allow Ontario County to re-open Deep Run. Please remember that if there is no lifeguard on duty, no swimming is allowed at public beaches.
Monitoring of Public Drinking Water Systems
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 New York State Department of Health to monitor the public drinking water for the presence of toxins associated with harmful algal blooms. Samples are collected of both raw (untreated) and finished (treated) water on a weekly basis for microcystin (the toxin that can be produced by blue green algae). All results to date have come back as undetectable. The water purveyors will continue to sample on a weekly basis through early October. Weekly results are posted on the CLWA website and can be found here.
For more infomation on drinking water and harmful algae blooms, the CLWA website has a list of Frequently Asked Questions which can be found here. This webpage also includes considerations for users of private water systems.
The above water quality observations and data are very promising this week. However, it is important to remember that conditions can change quickly on the lake. Typically, we have seen our most significant bloom events in the early to mid-September timeframe. Please use your visual indicators before entering the lake. Look for discolored water, surface streaking of blue green algae (cyanobacteria) or pea soup conditions.
If you have a question on a suspected bloom, please feel free to send in a photograph to HABs@canandaigualakeassoc.org. This email address is monitored by CLWA and Canandaigua Lake Watershed Council staff. We may be able to assist with identification though a clear photograph.
Volunteers and watershed staff will be continuing daily observations throughout September and early October, and we will communicate any significant changes in bloom activity through our weekly email updates, on our websites, and on the Association's facebook page.
Enjoy Labor Day weekend and consider using LED flares for the Ring of Fire!
So far this week:
• 38 surveys performed
• 7 Blooms reported
Welcome to your Friday Water Quality Update!
The good news is that the vast majority of our 10,500 acre lake and 36 miles of shoreline remains free of significant concentrations of blue green algae (cyanobacteria). As of 3:00 PM today (Friday) we have had zero bloom reports. Over the last two weeks, we have done two rounds of testing in 9 locations to look at average levels of blue green algae in the open water and all test results are showing low levels of cyanobacteria that are well below bloom levels. Secchi Disk measurements by staff and volunteers are also showing that our water clarity is holding at about 5.0-5.5 meters on average. The cloudy weather and slight north winds today have reduced any potential for blooms to form. Watershed staff looked at several locations on both the east and west sides of the lake and conditions at these locations looked clear as of 12:00 PM.
However, yesterday (Thursday) proved that conditions can change quickly. Yesterday, we had multiple reports of isolated blooms on the east side of the lake- especially in the Cottage City/Crystal Beach area. Deep Run Beach in Gorham (run by Ontario County) closed yesterday due to some visible concentrations of blue green algae. NYS Department of Health will test the water on Monday to determine if the beach can re-open.
Recent rains and duckweed
We were also reminded this week that the lake is connected to a larger ecosystem and watershed area. The rains of last week raised the level of the lake by about 9 inches. Although the lake surface received about 2 inches of rain on average- the 109,000 acre drainage area contributed the other seven inches of water in the lake. There is about 300 million gallons of water in an inch of lake depth- so approximately 2.1 billion gallons of water flowed into the lake from the surrounding watershed! The main outlet gates have been opened since the storms of last week and the lake level has been lowered by about 4.5 inches to 688.75 feet above sea level.
The southern half of the watershed, especially the Naples and Middlesex/Italy area had closer to 4 inches of rain. We had significant flooding in the Naples Creek watershed. The stream flow from Naples Creek and the West River ultimately flows through the High Tor wetland system. This wetland system supports a tremendous amount of duckweed and watermeal (harmless tiny aquatic plants) as part of this ecosystem. The major streamflows pushed much of this duckweed and watermeal into the lake. Within a week, we have seen these visually imposing floating mats make their way to the north end of the lake - 15 miles!
Duckweed and watermeal are harmless tiny floating aquatic plants that grow in the High Tor wetland system and are an important part of this ecosystem. However, many other items including debris and blue green algae can sometimes get caught up in these dense mats of duckweed, so please use caution if boating or swimming in them.
As we move into the weekend, if the hot weather combines with sunny/calm conditions, we can expect isolated blooms of blue green algae (cyanobacteria) to occur. If you notice discolored water, streaking, or surface scums - please avoid these areas. Conditions can change quickly so please use your visual indicators before going in the water. Look for signs of concentrations of algae. As recommended by the DEC, if you see it, avoid it.
If you have a question on a suspected bloom, please feel free to send in a photograph to HABs@canandaigualakeassoc.org. This email address is monitored by CLWA and Canandaigua Lake Watershed Council staff. We may be able to assist with identification though a clear photograph.
Volunteers and watershed staff will be continuing daily observations throughout August and September and we will communicate any significant changes in bloom activity through our weekly email updates, on our websites, and on the Association's facebook page.
Enjoy your weekend!
