The State Water Resources Control Board and Central Valley Regional Water Quality Control Board, in conjunction with the Big Valley Band of Pomo Indians, have issued site-specific advisory levels.  Image courtesy of California Water Boards

CLEAR LAKE, CA (MPG) - Visitors to Clear Lake are urged to exercise caution after recent testing by the Big Valley Band of Pomo Indians at multiple locations of the lake found harmful algal blooms with high levels of toxins that could pose a health threat to humans and their pets.

 Image courtesy of California Water Boards

  Image courtesy of California Water Boards

  Image courtesy of California Water Boards

The State Water Resources Control Board and Central Valley Regional Water Quality Control Board, in conjunction with the Big Valley Band of Pomo Indians, have issued site-specific advisory levels. At this time, the Lower Arm (bounded by Highway 29 on the south) and Oaks Arm (bounded by Highway 20 on the north) have multiple sites with danger level recreational advisories, meaning visitors should avoid contact with the water until further notice. Those visiting the area are encouraged to follow the below guidance and check Big Valley Band of Pomo Indians’ Cyanotoxins Webpage or the California HAB Reports Web Map for updated advisory levels.

The bloom occurring in the lake appears suspended on the water’s surface. Bloom conditions can change rapidly, as the winds and waves move or concentrate the bloom into different regions of the lake. The color of the water may also appear discolored as bright or dark green and brown. Because of the large size of the lake, there are currently advisories ranging from none to danger. Recreators are encouraged to follow the below guidance until further notice.

Caution

You can swim in this water, but stay away from algae and scum in the water.
Do not let pets and other animals go into or drink the water, or eat scum on the shore.
Keep children away from algae in the water and on the shore.
Do not drink the water or use it for cooking.
For fish caught here, throw away guts and clean fillets with tap water or bottled water before cooking.
Do not eat shellfish from this water.

Warning

No swimming
Do not let pets and other animals go into or drink the water, or eat scum on the shore.
Stay away from scum, and cloudy or discolored water.
Do not eat shellfish from this water.
Do not use this water for drinking or cooking. Boiling or filtering will not make the water safe.
For fish caught here, throw away guts and clean fillets with tap water or bottled water before cooking.

Danger

Stay out of the water until further notice, including watercraft.
Do not let pets and other animals drink or go into the water, or go near the scum.
Stay away from scum, and cloudy or discolored water.
Do not eat fish or shellfish from this water.
Do not use this water for drinking or cooking. Boiling or filtering will not make the water safe.

Cyanobacteria, a group of organisms that form harmful algal blooms, can produce potent toxins that may cause itching skin and rashes, as well as gastrointestinal distress, headaches, agitation and weakness, or abnormal breathing if HAB material is swallowed while swimming. Dogs and children are most susceptible to exposure because of their smaller body size, increased potential to swallow water while swimming, and tendency to stay in the water longer. If you suspect exposure, wash your children and dog immediately.

The Water Boards recommend that people practice healthy water habits while enjoying the outdoors this summer at your local lake, river or stream: 

Heed all instructions on posted advisories if present 
Avoid algae and scum in the water and on the shore 
Keep an eye on children and pets 
If you think a harmful algal bloom or toxic algal mats are present, do not let pets and other animals go into or drink the water or eat scum/algal mats on the shore 
Don’t drink the water or use it for cooking 
Wash yourself, your family and your pets with clean water after water play 
If you catch fish, throw away guts and clean fillets with tap water or bottled water before cooking 
Avoid eating shellfish if you think a harmful algal bloom is present 

Get medical treatment immediately if you think that you, your pet, or livestock has gotten sick after going in the water. Be sure to alert the medical professional to the possible contact with cyanobacteria. Also, make sure to contact the local county public health department. 

Water quality monitoring for HABs in Clear Lake is conducted by Big Valley Band of Pomo Indians, which began a Cyanobacteria and Cyanotoxin Monitoring Program on Clear Lake in 2014 with another shoreline Tribe, Elem Indian Colony. The Tribes’ environmental departments have collaborated to share water monitoring data with the Water Boards and local agencies. Lake County posts advisory signs to notify visitors of blooms. The Water Boards will provide regular updates to advisory levels based on monitoring results to the California HAB Reports Web Map. 

To report a bloom, do one of the following:

Fill out the Bloom Report form on the HABs Portal: https://mywaterquality.ca.gov/habs/do/bloomreport.html
Email: [email protected]
Call the HABs hotline: 1-844-729-6466 (toll free)
Contact your County Public Health Office

 Photo courtesy of Jerry Bruns