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Caution for Blue-Green Algae in Clear Lake

Caution for Blue-Green Algae (Cyanobacteria) in Clear Lake
Current cyanotoxin results for lakewide sampling conducted August 15 and August 21, 2018:

Microcystin cyanotoxin detected at 12 of 21 sampled sites, 4 at CAUTION trigger levels: the center of the Oaks Arm (CL-4), Clearlake Oaks shoreline (CLOAKS01), Elem shoreline (ELEM01) and Cache Creek at Hwy53 (SHADY01). The remaining sites do not reach any trigger levels, were Non Detect for toxins, or were not sampled due to being inaccessible. The next monitoring event will be September 10, 2018. Please see the below map of locations sampled on August 15 and August 21, 2018, with results received on August 29, 2018. Please also refer to the press release from August 13, 2018 for the previous results:

 Algae Map August 2018

Algae Map Legend

This week's reading are lower than previously, but we need two consecutive improved readings before we can change the level of alert for cyanobacteria that went out on August 10, 2018.  Please be aware that you will see signs for a higher level (for example, danger instead of caution) until we have two readings at the lower level. Public Health also needs two consecutive Non Detect readings before we remove signs. Blue-green algae can pose health risks, particularly to children and pets. We urge 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 recommended that people and their pets avoid contact with water and avoid swallowing lake water in an algae bloom area.
Public Health recommends following the below from the Statewide Guidance on Cyanobacteria and Harmful Algal Blooms:
•    Take care that pets and livestock do not drink the water, swim through algae, scums or mats, or lick their fur after going in the water.  Rinse pets in clean water to remove algae from fur.
•    Avoid wading, swimming, jet or water skiing in water containing algae blooms, scums or mats.
•    Do not drink, cook or wash dishes with untreated surface water from these areas under any circumstances; common water purification techniques such as camping filters, tablets and boiling do not remove toxins.
•    People should not eat mussels or other bivalves collected from these areas.  Limit or avoid eating fish from these areas; if fish are consumed, remove the guts and liver, and rinse filets in clean drinking water.
•    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.  Also, make sure to contact the local county public health department at (707) 263 - 1090.


Water Faucet
Urgent Health Advisory

Effective immediately, people on private water systems whose tap water comes from their own private intake into the lake, in the Oaks Arm and Lower Arm of Clear Lake should not drink the water.

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