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Cyanobacteria Update

Significant Cyanobacteria/Algae Bloom; Concerning Cyanotoxin Levels Detected at Multiple Clear Lake Sites; Danger Level at Four Locations

Lake County, CA (July 3, 2020) – Clear Lake is a national treasure, and was recently named Best Bass Lake of the past decade by BASSMASTER Magazine, as previously reported by LakeCoNews.

It is also a large and biologically diverse natural body of water, and therefore dynamic in water quality.  Given the warm weather and the long hours of sunlight this time of year, we are seeing large cyanobacteria/blue-green algae blooms at various places around the lake.  In some locations, cyanotoxin has been detected at “DANGER” levels.

Water monitoring data is one factor that helps all of us make healthy water-based recreation choices, and lake water monitoring is regularly conducted by the Big Valley Band of Pomo Indians and Elem Indian Colony at approximately 30 Clear Lake sites.  This is a valuable service for all who use our lake.
 
During June 23, 2020 sampling, worrisome levels of Cyanotoxin were detected at 10 sites, with 4 sites reaching the “Danger” level (also see specific indicators on the map, below):
• Austin Park (AP01, Lower Arm)-- Danger
• Buckingham (BP, Lower Arm)-- Danger
• Jago Bay (JB, Lower Arm)-- Danger
• Sulphur Bank Mercury Mine shoreline (SBMMEL01, Oaks Arm)-- Danger
• Lily Cove (LC01, Lower Arm)-- Warning
• CL-4 (Oaks arm, center of arm)-- Caution
• CLV7—Caution
• Elem Indian Colony shoreline (ELEM01, Oaks Arm)-- Caution
• Keeling Park (KP01, Upper Arm)-- Caution
• Lucerne (LUC01, Upper Arm)—Caution

 

SITE ID

LAB RESULTS IN µg/L

COMMENTS

Level of Concern

JB

76.8

Bloom present

DANGER

BP

45.0

Bloom present

 

DANGER

AP01

44.7

Thick Bloom present

DANGER

SBMMEL01

23.2

Heavy Bloom present

 

DANGER

LC01

9.79

Heavy Bloom present

 

WARNING

ELEM01

4.86

Thick Bloom present

 

CAUTION

KP01

0.41

Bloom present

 

CAUTION

CLV7

0.26

Heavy Bloom present

 

CAUTION

CL-4

Bloom present, high levels of toxin-producing genes

CAUTION

LUC01

 

Bloom present, high levels of toxin-producing genes

 

CAUTION


While much of the aquatic plant growth visible in the lake right now is harmless, cyanobacteria, when present in sufficient abundance, can produce cyanotoxins, which pose health hazards to humans, livestock, and pets.  Varying levels of the toxin can be detected at different locations, so there is no need to be overly concerned about activities in areas of the lake where algae blooms are not present.
 
At the “DANGER” and “WARNING” levels, toxins from algae in the water can harm people and kill animals.  Everyone should stay out of the water in those areas and not touch scum in the water or on the shore.  Pets should stay out of the water, not drink the water, and avoid the scum.  Fish and shellfish should not be eaten from those areas.  Symptoms of exposure include skin rashes, eye irritation, diarrhea, and vomiting.  Pets who contact the toxin can experience seizures and death.
 
Contact a medical provider or veterinarian if symptoms due to exposure are suspected.

For current cyanotoxin lab results, please visit the Clear Lake Water Quality Facebook page  and Big Valley Band of Pomo Indians’ cyanotoxin monitoring website.  Images, graphics and other resources regarding this data are available:
https://www.bvrancheria.com/clearlakecyanotoxins
https://www.facebook.com/ClearLakeWaterQuality/
 
Further resources are available at the following webpages:
http://www.lakecountyca.gov/cyanobacteria/
http://www.lakecountyca.gov/cyanohealth/
 
CDC guidance regarding harmful algal blooms can be found here:
https://www.cdc.gov/habs/materials/factsheet-cyanobacterial-habs.html
 
The BASSMASTER and LakeCoNews pieces referenced at the outset of this release can be found here:
https://www.bassmaster.com/best-bass-lakes/slideshow/best-bass-lakes-2010s
http://www.lakeconews.com/index.php/news/65907-clear-lake-named-best-bass-fishery-of-the-past-decade
 
Gary Pace, MD, MPH

Cyano Map

Coronavirus
2nd COVID-19 Related Death

It is with great sadness I report a second Lake County resident has died with a COVID-19-related illness.

Death info