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County issues updated warnings due to cyanobacteria bloom on Clear Lake
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LAKE COUNTY, Calif. – Late Friday, Lake County Public Health issued an updated advisory with warnings about potential health risks due to a seasonal cyanobacteria, or blue-green algae, bloom on Clear Lake.
The bloom is taking place in all three arms – Lower, Oaks and Upper – of Clear Lake, the county reported.
Bloom conditions can change rapidly and wind and waves may move or concentrate the bloom into different regions of Clear Lake.
Officials said testing of sites in Clearlake Oaks and Richmond Park had been confirmed at “danger” levels.
At the same time, they urged boaters and recreational users of Clear Lake to use caution in coming in contact with the water at the Elem Indian Colony shoreline in Clearlake Oaks, at Redbud Park in Clearlake and Keeling Park in Nice.
Lakewide sampling on July 13 indicated that blooms were present in several locations on Clear Lake, officials reported.
The county said the lab results for the Clearlake Oaks site showed a level of 480 micrograms per liter, or ug/L, which is at the danger level. The Richmond Park site lab result showed a level of 25 ug/L, which is also at the danger level.
The Elem site showed a level of 4.9 ug/L, the Redbud Park site had a lab result of 4.1 ug/L and the Keeling Park site showed a lab result of 4 ug/L. The county said all of these results are at the caution level.
For information on all of the sites tested, visit http://www.bvrancheria.com/clearlakecyanotoxins.
The Clearlake Oaks location is close to a drinking water supply. Drinking water at that site was tested last on July 10 and was below the Environmental Protection Agency recommended guideline of 0.3 µg/L and was safe to drink. Sampling of drinking water at the the site will next occur on Monday, July 23.
Blue-green algae can pose health risks, particularly to children and pets. The county urges people to choose safe activities when visiting the Oaks arm and parts of the lower arm of Clear Lake and wherever blooms are visible.
It is strongly recommend that people and their pets avoid contact with water, and avoid swallowing lake water in an algae bloom area.
The algae bloom can appear as cut grass in the water or blue-green, white or brown foam, scum or mats that can float on the water’s surface and accumulate along the shoreline and boat ramp area.
Recreational exposure to toxic blue-green algae can cause eye irritation, allergic skin rash, mouth ulcers, vomiting, diarrhea, and cold and flu-like symptoms.
Pets can be especially susceptible because they tend to drink while in the water and lick their fur after.
Get medical treatment immediately if you think that you, your pet, or livestock might have been poisoned by blue-green algae toxins. Be sure to alert the medical professional to the possible contact with blue-green algae.