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8/16/2024
WT Staff
 August 16, 2024 1223 pm PDT
Clear Lake Cyanotoxin Surveillance
Sarah Ryan is Director of EPA for Big Valley Band of Pomo Indians, heading up the HAB surveillance program for Clear Lake in Lake County. WTCAL caught up with Ryan last night for an elucidation on one of our favorite subjects. Ryan pointed out the point and purpose of cyanobacteria monitoring is not only if there is a bloom observed in a water body, rather, what toxins are present at what concentration?
What is the point of tracking HABs if we have no toxilogical monitoring? Investment in routine sampling and lab testing over the last decade underscores the CDC guidance: cyanotoxins may be present where an algal mat is no longer visible. If that's not alarming enough, cyanotoxins can be inhaled. USGS study of major rivers in the USA have also found cyanotoxins present in dynamic water. Communication on this subject requires diligence, absolute transparency and much greater effort toward public awareness and education.
US EPA Guidelines for cyanotoxins in recreational water are based on the maximum level presumed to cause no health effects over ten days of exposure. World Health Organization guidance indicates symptoms of cyanotoxin poisoning may not be felt until the damage is serious. Any discrepancy in levels deemed safe is therefore concerning. WT recently wrote about the difference in US EPA guidance vs Canadian public health standards for exposure to cyanotoxins here. . For all our concern about difference of public health opinion between the US and Canada, the State of California takes this debate to another realm, an order of magnitude deviation lower than US EPA guidance.
According to Office of Environmental Health Hazard Assessment of the California Environmental Protection Agency assessment of six cyanotoxins (2012), the safe limit for exposure to any one of four microcystins is ten times lower than the US EPA guideline for recreational water .
The discrepancy between California EPA guidance and Canada Health guidance is wider yet. As we delve deeper into this critical public health matter, the safety and security of drinking water supplies rises to the forefront of our investigation. More to follow.
The weekly bluegreen update from California Water Quality Monitoring Boards anticipated last week Friday, August 9 has not been posted as of this report.
The latest HAB Recent Bloom report is dated August 2, seven water bodies are posted with DANGER level advisories, including Lago Los Osos, Lake Chabot, Lake Anza, Discovery Bay, Contra Loma Reservoir, Big Break Regional Shoreline and Copsey Creek. Three water bodies have been posted with HAB Warning level advisories, including Discovery Bay, Tahoe Keys and San Luis Reservoir's Dinosaur Point Boat Launch. Caution advisories have been activated for another 31 sites. See the California HAB tracker report with advisories by watershed region, HAB DANGER and WARNING advisories are pinned to the map with bluegreen tags, the full list is here.
WT HAB Tracker
from the satellite monitoring program of the NOAA National Centers for Coastal Ocean Science(NCCOS) and State sources where available
Louisiana: The latest upload from the NCCOS was captured August 15 at higher wind speed 7.9 mph. This image is mostly cloud obscured, a view of Lakes Verret and Palourde, as well as Avoca Island Cutoff, the concentration slightly lower in this recent image 700 thousand cells per 100 ml.
The prior image shows Lac des Allemands with high concentration hot spots in the west bay along shore up to 3 million cells. Lakes Pontchartrain and Maurepas are clear again, no HAB activity observed. Lake Fields is showing a high concentration HAB, 1 million in the north half and 2 million cells in the south half. Check out the latest satellite image from NCCOS here.
Lake Erie west basin
The latest image from NCCOS was captured August 15 at wind speed 7.7 mph, mostly cloud obscured with a view of the southwest water between clouds. This visible part of the HAB presents with concentration 1 million cells around the North Maumee Bay to 600 thousand cells per 100 ml north of Monroe. The Aug 14 image is clear and taken at a lower wind speed, revealing the full extent of the HAB with extreme high concentration hot spots up to 6 million cells per 100 ml, see the satellite image here.
New York
The latest image of Lake Champlain was captured August 15, a cloud obscured image at unknown wind speed. The previous image August 14 is a clear view of northeast Baie Missisquoi appears full of bluegreen algae at extreme high concentration 1 to 3 million cells per 100 ml on both sides of the international border. This bloom reaches south as far as the channel from North Hero Island to Isle la Motte, the south portion of the bloom at 900 thousand cells per 100 ml. St Albans Bay HAB is partially cloud obscured, we see the inner shoreline edge at 1 million cells per 100 ml. Lake Carmi appears clear with no HAB activity; Shelburne Pond is still rocking 2 million cells concentration in Vermont. See our latest report here.
One hundred and sixty-three active HABs are confirmed in New York Friday morning, down from 171 yesterday. First HABs of the season have been confirmed for Java Lake, Lake Clear and Gorton Lake. New bluegreen reports have come on for Honeoye, Hyde, Chautauqua and Red House Lake, all experiencing a new wave of HABs, some of these water bodies coming out of the 2024 archives after a period of no bluegreen activity. Reports made prior to Aug 1 have gone to the archives. See the impacted water bodies list here.
Georgia:
No new information has been found pertaining to bluegreen algae reports in Georgia since our last update. Georgia Environmental Protection Division does accept reports from the public of suspicious algal blooms. WTGA.us has requested an update from Georgia EPD, more to follow.
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